Inclusion Criteria:

• Breast cancer patients with biopsy proven invasive cancer
• Clinically and radiographically node negative
• No indication of metastatic disease
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-1
• Synchronous bilateral invasive cancer allowed
• Negative serum pregnancy test within one month from the radiation therapy (RT) boost delivery
• Willingness to participate in the clinical trial and adhere to the study protocol
• Individuals of all races, genders and ethnic groups are eligible for this trial

Exclusion Criteria:

• Need for neoadjuvant chemotherapy
• Inflammatory breast cancer (cT4)
• Multicentric tumor
• Prior ipsilateral breast or thoracic RT
• Contraindication for baseline magnetic resonance imaging (MRI)
• Contraindication for surgery
• Distant metastatic disease
• Other synchronous cancer (besides bilateral breast)
• Contraindication to radiation therapy (presence of scleroderma or other collagen vascular disease)
• Any serious or uncontrolled medical disorder that, in the opinion of the investigator, may increase the risk associated with study participation or study drug administration, impair the ability of the subject to receive protocol therapy, or interfere with the interpretation of study results

Inclusion Criteria:

• Histologically confirmed adenocarcinoma of the prostate diagnosed within the last 9 months. Patients on active surveillance with evidence of disease progression are eligible to the protocol as long as they meet the eligibility criteria and have a recent prostate biopsy (within 9 months)
• Low-risk and intermediate-risk patients are eligible according to the following guidelines:
• Low and intermediate-risk disease defined as:
• Clinical stage T1-T2 and Gleason =< 7 and prostate specific antigen (PSA) < 15 ng/ml
• Lymph node evaluation by either computed tomography (CT) or magnetic resonance imaging (MRI) and bone scan are optional and are left at the discretion of the treating physician
• Prostate MRI is recommended by not mandatory
• No alpha reductase inhibitors use within 2 weeks of randomization. A washout period of 2 weeks is required prior to randomization
• Eastern Cooperative Oncology Group status 0-1
• Judged to be medically fit for brachytherapy by a radiation oncologist
• Concurrent, neoadjuvant and/or adjuvant androgen deprivation therapy (ADT) is not permitted
• Prostate volume by trans-rectal ultrasound (TRUS) =< 60 cc
• International Prognostic Scoring System (IPSS) =< 20 (alpha blockers allowed)
• Patients must sign a study specific informed consent form prior to study entry
• Patients must by accessible for treatment and follow-up. Patients registered on this trial must be treated and followed at the participating center. Investigators must assure themselves that patients enrolled in this trial will be available for complete documentation of the treatment, adverse events, and follow up
• Protocol treatment is to begin within 4 weeks of patient randomization

Exclusion Criteria:

• Patients with a history of other malignancies, except: adequately treated non-melanoma skin cancer, or other solid tumors curatively treated with no evidence of disease for >= 5 years
• Prior or current bleeding diathesis
• Radical surgery for carcinoma of the prostate, prior pelvic radiation, prior chemotherapy for prostate cancer, prior transurethral resection of the prostate (TURP), prior cryosurgery of the prostate
• Stage T3b and evidence of nodal or distant metastatic disease on diagnostic CT, MRI or bone scan
• Subjects who have plans to receive other concomitant or post treatment adjuvant antineoplastic therapy while on this protocol including surgery, cryotherapy, conventionally fractionated radiotherapy, hormonal therapy, or chemotherapy given as part of the treatment of prostate cancer
• Severe, active co-morbidity, defined as follows:
• Unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months
• Transmural myocardial infarction within the last 6 months
• Acute bacterial for fungal infection requiring intravenous antibiotics at the time of registration
• Chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy within 30 days before registration
• Hepatic insufficiency resulting in clinical jaundice and/or coagulations defects; note, however, that laboratory tests for liver function and coagulation parameters are not required for entry into this protocol
• Acquired immune deficiency syndrome (AIDS) based upon current Centers for Disease Control and Prevention (CDC) definition; note, however, that human immunodeficiency virus (HIV) testing is not required for entry into this protocol. The need to exclude patients with AIDS from this protocol is necessary because the treatments involved in this protocol may be significantly immunosuppressive. Protocol-specific requirements may also exclude immumo-compromised patients
• Patients with history of inflammatory colitis (including Crohn's disease and ulcerative colitis) or collagen vascular diseases including rheumatoid arthritis and lupus are not eligible
• Subjects who have a history of significant psychiatric illness
• Men of reproductive potential who do not agree that they or their partner will use an effective contraceptive method such as condom/diaphragm and spermicidal foam, intrauterine device (IUD), or prescription birth control pills

Inclusion Criteria

• Biopsy proven and metastatic colon cancer
• Candidate for Second-line or later line therapy with irinotecan-based chemotherapy regimen with starting dose of irinotecan at 180 mg/m2 q2w. Participants who have had prior irinotecan will be eligible if they are off irinotecan for at least three months and stools have returned to baseline consistency.
• Performance Status (PS) 0-1
• Lab values as acceptable for trials: Absolute Neutrophil Count( ANC) >1500/uL; Creatinine < 1.5 x Upper Limit of Normal (ULN); Transaminases < 5x ULN; Bilirubin < 1.5 x ULN; Albumin > 3.0 g/dL
• No known UGTA1A* genotype

Exclusion Criteria

• Grade two diarrhea or greater (4-6 movements per day over baseline)
• Inability to take oral supplements
• Current antibiotic therapy
• Baseline grade 3-4 diarrhea Participants with grade two diarrhea should undergo stool evaluation with stool test for bacteria (Salmonella, Shigella, Campylobacter, Yersinia Mycobacterium), bacterial toxin (Clostridium difficile), ova and parasites (Giardia, Entamoeba, Isospora, Cyclospora, Cryptosporidium, Microsporidium), or viruses (Cytomegalovirus), associated with an ongoing active infection and diarrhea. They will be eligible if this evaluation shows no infection.
• History of the following infections and/or disease which could lead to diarrhea:
• History of prior positive gastrointestinal biopsy, gastrointestinal culture, or stool test for bacteria (Salmonella, Shigella, Campylobacter, Yersinia, Mycobacterium), bacterial toxin (Clostridium difficile), ova and parasites (Giardia, Entamoeba, Isospora, Cyclospora, Cryptosporidium, Microsporidium), or viruses (Cytomegalovirus), associated with an ongoing active infection and diarrhea unless fully treated with at least three months normal stool.
• History of ulcerative colitis, Crohn's disease, celiac sprue (gluten-enteropathy), chronic pancreatitis, malabsorption, or any other gastrointestinal disease associated with diarrhea.

Inclusion Criteria:

• HER2-positive status will be based on pretreatment biopsy material and defined as an immunohistochemistry (IHC) score of 3+ and/or positive by in situ hybridization (ISH) according to current American Society of Clinical Oncology (ASCO) College of American Pathologists (CAP) guidelines. Central testing is not required * Known hormone receptor (HR) status as defined by ASCO/CAP guidelines (based on pretreatment biopsy material). Hormone receptor positive status can be determined by either known positive estrogen receptor (ER) or known positive progesterone receptor (PR) status; hormone receptor negative status must be determined by both known negative ER and known negative PR
• Patients with clinical stage T1-4, N0-3 disease at presentation and residual invasive disease postoperatively as defined above are eligible. (Note: Patients with T1a/bN0 tumors are not eligible at initial breast cancer diagnosis are not eligible)
• Patients with residual HR-negative, HER2 positive (+) disease in the breast and/or lymph nodes per the surgical pathology report are eligible; however, patients with HR+ HER2+ cancers must have node-positive residual disease per the surgical pathology report in order to qualify for the study. The presence of residual invasive disease in the breast is not mandatory for these patients
• Patients with weakly ER-positive (1-10%) breast cancer (based on the pretreatment core biopsy) are eligible even if they have node-negative disease per the surgical pathology report
• The residual disease tissue (breast and/or lymph nodes) is not required to be HER2-positive, as eligibility for NCI-2020-03770 (A011801) is based on a positive HER2 status at the time of the initial breast cancer diagnosis * Note: The presence of micrometastases in lymph nodes after preoperative therapy counts as residual disease, whereas the presence of isolated tumor cells does not
• Patients with synchronous bilateral invasive disease are eligible provided both lesions were confirmed to be HER2-positive, and at least one of the lesions meets the criteria outlined above. Multifocal disease is allowed, as long as the largest biopsied breast tumor was HER2-positive
• Patients must have received neoadjuvant chemotherapy with one of the following regimens: docetaxel/trastuzumab/pertuzumab (THP), paclitaxel/methotrexate/cisplatin (TMP), doxorubicin/cyclophosphamide/paclitaxel/trastuzumab/pertuzumab (AC-TH(P)); docetaxel/carboplatin/trastuzumab/pertuzumab (TCH(P)); fluorouracil/doxorubicin/cyclophosphamide-docetaxel/trastuzumab/pertuzumab (FAC-TH(P)), or fluorouracil/epirubicin/cyclophosphamide-docetaxel/trastuzumab/pertuzumab (FEC-TH(P)). Note: apart from TCHP, where T is docetaxel, treatment with docetaxel or paclitaxel is acceptable
• Prior receipt of T-DM1 in the neoadjuvant setting is not allowed.
• Prior treatment must have consisted of >= 6 cycles of chemotherapy and HER2-directed therapy, with a total duration of >= 12 weeks, including at least 9 weeks of preoperative taxane and trastuzumab with or without pertuzumab (or Food and Drug Administration [FDA]-approved biosimilars). Patients who have received at least 9 weeks of preoperative taxane, pertuzumab and margetuximab are also eligible if they received >= 6 cycles of systemic therapy prior to enrollment. Note: Patients who complete at least nine of a planned twelve doses of weekly paclitaxel, or three of a planned four doses of docetaxel, but discontinue prematurely due to toxicity are eligible. Patients receiving dose-dense chemotherapy regimens are also eligible. Prior use of nab-paclitaxel (Abraxane) instead of paclitaxel or docetaxel is permitted. Prior use of subcutaneous trastuzumab (Hylecta) and subcutaneous trastuzumab and pertuzumab (Phesgo) is also allowed.
• Patients who received neoadjuvant systemic therapy which included experimental HER2-targeted therapy/therapies are potentially eligible, as long as the investigational agent was not a HER2-targeted antibody-drug conjugate (e.g. T-DM1, DS-8201a [trastuzumab deruxtecan]) or a HER2 targeted tyrosine kinase inhibitor (TKI) (e.g. tucatinib, lapatinib, neratinib).
• Patients may have received =< 1 cycles of T-DM1 in the adjuvant setting. Note: These patients will be randomized to receive a further 14 cycles of T-DM1 and tucatinib/placebo as tolerated. The most recent cycle of T-DM1 should have been administered =< 5 weeks prior to registration * Note: Both of the following two criteria need to be met for the patient to be eligible for this study
• An interval of no more than 12 weeks between the completion date of the last definitive treatment (e.g. postoperative chemotherapy or radiation, or if neither given, breast surgical date) and the date of registration. Concurrent radiation therapy is permitted while receiving study treatment
• Patients must be registered on study within =< 180 days of the date of the most recent definitive breast cancer surgery (not including reconstructive surgery)
• All systemic chemotherapy should have been completed preoperatively unless participating in EA1181 (CompassHER2 pathologic complete response [pCR]) or the BIG DECRESCENDO Trial (which is very similar to CompassHER2 pCR in terms of study design, drugs, and eligibility). However, patients who received 4 cycles of neoadjuvant THP off study can receive a further 2-4 cycles of chemotherapy postoperatively to meet eligibility for A011801. Patients who participated in EA1181 or MA41 and proceeded to surgery immediately after the de-escalated trial regimen must receive postoperative chemotherapy to complete a total of >= 6 cycles of systemic treatment prior to enrollment on A011801, as outlined above (e.g. 4 cycles pre-operatively, and 2 cycles post-operatively). The postoperative chemotherapy regimen prescribed is at the discretion of the treating oncologist (i.e. 2-4 cycles AC or THP, other). Continuation of trastuzumab + pertuzumab (HP) pre- or post-operatively as maintenance therapy (while awaiting a surgical date or an official pathology report) is allowed for all study participants
• Toxicities related to prior systemic treatment should have resolved or be at baseline, apart from alopecia and peripheral neuropathy =< grade 1
• Adequate excision: surgical removal of all clinically evident disease in the breast and lymph nodes as follows:
• Breast surgery: total mastectomy with no gross residual disease at the margin of resection, or breast-conserving surgery with histologically negative margins of excision
• For patients who undergo breast-conserving surgery, the margins of the resected specimen must be histologically free of invasive tumor and ductal carcinoma in situ (DCIS) as determined by the local pathologist. If pathologic examination demonstrates tumor at the line of resection, additional operative procedures may be performed to obtain clear margins. If tumor is still present at the resected margin after re-excision(s), the patient must undergo total mastectomy to be eligible. Patients with margins positive for classic lobular carcinoma in situ (LCIS) are eligible without additional resection
• Lymph node surgery ** The axilla needs to be evaluated with either sentinel node biopsy or axillary lymph node dissection. If patients have a sentinel lymph node biopsy and sentinel nodes are negative, no further axillary treatment is necessary. If patients have isolated tumor cells (ITCs) in the setting of residual breast disease, at least one of the following is required: axillary lymph node dissection (ALND) or planned nodal irradiation. If patients have micro- or macro-metastatic nodal disease, ALND and planned nodal irradiation are required. Of note, co-enrollment on Alliance A011202 is not allowed
• Eastern Cooperative Oncology Group (ECOG) performance status 0-1
• Absolute neutrophil count (ANC) >= 1,000/mm^3
• Hemoglobin >= 8 g/dL (Note: packed red blood cells [PRBC] transfusion is not permitted to achieve eligibility)
• Platelet count >= 100,000/mm^3
• Creatinine =< 1.5 x upper limit of normal (ULN)
• Total bilirubin =< 1.0 x upper limit of normal (ULN) or direct bilirubin within the institutional normal range for patients with Gilbert's syndrome
• Aspartate aminotransferase (AST)/alanine aminotransferase (ALT) =< 2.5 x upper limit of normal (ULN)
• Screening left ventricular ejection fraction (LVEF) >= 50% on echocardiogram (ECHO) or multiple-gated acquisition (MUGA) after receiving neoadjuvant chemotherapy and no decrease in LVEF by more than 15% absolute percentage points from the pre-chemotherapy LVEF. Or, if pre-chemotherapy LVEF was not assessed, the screening LVEF must be >= 55% after completion of neoadjuvant chemotherapy. Note: LVEF assessment may be repeated once up to 3 weeks following the initial screening assessment to assess eligibility

Exclusion Criteria:

• No adjuvant treatment with any anti-cancer investigational drug within 28 days prior to registration
• Not pregnant and not nursing, because this study involves an agent that has known genotoxic, mutagenic and teratogenic effects. Therefore, for women of childbearing potential only, a negative serum pregnancy test done =< 7 days prior to registration is required
• Patients with known active and/or untreated hepatitis B or hepatitis C or chronic liver disease are ineligible. Patients with a diagnosis of hepatitis B or C that has been treated and cleared and normal liver function are eligible to participate in the study if the other eligibility parameters are met
• Stage IV (metastatic) breast cancer
• History of any prior (ipsi- or contralateral) invasive breast cancer within 3 years of registration
• Patients with ER+ HER2+ residual invasive disease that is lymph node-negative per the surgical pathology report
• Evidence of recurrent disease following preoperative therapy and surgery
• Patients for whom radiotherapy would be recommended for breast cancer treatment but for whom it is contraindicated because of medical reasons (e.g., connective tissue disorder or prior ipsilateral breast radiation)
• History of exposure to the following cumulative doses of anthracyclines: doxorubicin > 240 mg/m^2; epirubicin or liposomal doxorubicin-hydrochloride (Myocet) > 480 mg/m^2. For other anthracyclines, exposure equivalent to doxorubicin > 240 mg/m^2
• Cardiopulmonary dysfunction as defined by any of the following:
• History of National Cancer Institute (NCI) CTCAE version (v) 5.0 grade >= 3 symptomatic congestive heart failure (CHF) or New York Heart Association (NYHA) criteria class >= II
• Angina pectoris requiring anti-anginal medication, serious cardiac arrhythmia not controlled by adequate medication, severe conduction abnormality, or clinically significant valvular disease
• High-risk uncontrolled arrhythmias: i.e., atrial tachycardia with a heart rate > 100/min at rest, significant ventricular arrhythmia (ventricular tachycardia) or higher-grade atrioventricular block (AV)-block (second degree AV-block type 2 [Mobitz 2] or third degree AV-block)
• Significant symptoms (grade >= 2) relating to left ventricular dysfunction, cardiac arrhythmia, or cardiac ischemia while or since receiving preoperative therapy
• History of a decrease in left ventricular ejection fraction (LVEF) to < 40% with prior trastuzumab treatment (e.g., during preoperative therapy)
• Uncontrolled hypertension (systolic blood pressure > 180 mmHg and/or diastolic blood pressure > 100 mmHg)
• Current severe, uncontrolled systemic disease
• Major surgical procedure unrelated to breast cancer or significant traumatic injury within 28 days prior to registration or anticipation of the need for major surgery during the course of study treatment
• History of intolerance, including grade 3 to 4 infusion reaction or hypersensitivity to trastuzumab or murine proteins or any components of the product
• Peripheral neuropathy of any etiology that exceeds grade 1
• Assessment by the investigator as being unable or unwilling to comply with the requirements of the protocol
• Use of a strong CYP3A4 or CYP2C8 inhibitor within 2 weeks, or use of a strong CYP3A4 or CYP2C8 inducer within 5 days prior to registration is prohibited.
• Please note that use of sensitive CYP3A substrates should be avoided two weeks before registration and during study treatment. Additionally, CYP3A4 or CYP2C8 inducers are prohibited as concomitant medications within 5 days following discontinuation of tucatinib treatment. Patients who require medications that are known to be sensitive substrates of CYP3A4 with a narrow therapeutic window should be excluded.

• Patients must have histologically or cytologically confirmed stage IV NSCLC (includes M1a, M1b, and M1c stage disease, AJCC 8th edition). Patients with Stage IIIB and IIIC disease are eligible if they are not candidates for combined chemotherapy and radiation; such cases should be discussed in a multidisciplinary tumor board.
• Eligible NSCLC tissue histologies will include squamous cell carcinoma (enrolled and treated in Arm 1), and nonsquamous histologies (e.g. adenocarcinoma, large cell carincoma, etc.; enrolled and treated in Arm 2). Patients with mixed squamous, e.g., adenosquamous, histology will be enrolled and treated on Study Arm 1. Patients with any evidence of Small Cell Carcinoma will be excluded from study participation.
• Patients may have ANY PD-L1 expression Tumor Proportion Score (TPS) status. Tissue testing for PD-L1 is strongly recommended. If PD-L1 expression TPS is unevaluable or the testing could not be completed, the patient may still be eligible.
• Patients must have measurable or non-measurable disease. The presence of malignant pleural fluid alone is sufficient to satisfy this eligibility criterion. Baseline imaging assessments and measurements used to evaluate all measurable or non-measurable sites of disease must be done within 4 weeks prior to study registration. NOTE: If patient receives pemetrexed, follow institutional guidelines to drain fluids.
• Patients must be ≥ 18 years of age.
• Patients must have an ECOG Performance Status of 0 to 2
• Patients must NOT have received the following:
• Prior systemic chemotherapy or immunotherapy for advanced metastatic NSCLC. Patients treated with any prior checkpoint inhibitors for metastatic lung cancer are ineligible. Chemotherapy and immunotherapy for non-metastatic disease (e.g. adjuvant therapy) or immunotherapy for locally advanced Stage III disease is allowed if at least 6 months have elapsed between the last dose of the prior therapy and study registration. Local therapy, e.g. palliative radiation, is allowed as long as a period of 7 days has passed between completion of local

  therapy and study registration. Registration prior to treatment during the 7 days

  is allowed. Palliative radiation must be to non-target lesions.
  • Methotrexate (MTX) given in low doses for non-malignant conditions with last dose at least 14 days prior to date of registration will be allowed. Other low dose chemotherapeutics for non-malignant conditions will be considered, but review by the study chair is required.
  • For Arm 1 (Squamous Lung Cancer): Patients must not have pre-existing peripheral neuropathy that is ≥ Grade 2 by CTCAE v.5.0. Patients must not have known sensitivity to any component of carboplatin or paclitaxel or nabpaclitaxel.
  • Patients with known EGFR mutations (except exon 20 insertion), BRAF mutations (V600), MET Exon14 skipping or ALK or ROS1 translocations that can be treated with oral tyrosine kinase inhibitors are excluded.
  • Patients with treated brain metastases are eligible if follow-up brain imaging after central nervous system (CNS)-directed therapy shows no evidence of progression. Patients with asymptomatic new (at screening) or progressive brain metastases (active brain metastases at screening) or leptomeningeal disease are eligible if the treating physician determines that immediate CNS specific treatment is not required and is unlikely to be required during the first cycle of therapy.
  • Patients are eligible if off steroids for at least 7 days prior to protocol treatment.
  • Palliative radiation to non-target lesions (bone metastasis) is allowed if patient develops symptoms.
  • Anticonvulsants are allowed.
  • Patients with asymptomatic, sub-centimeter brain metastasis who at the discretion of investigators do not need immediate CNS directed therapies are eligible.
  • Patients with prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial.
  • Patients must not have known pre-existing and clinically active interstitial lung disease, or a known history of (non-infectious) pneumonitis that required steroids, or current pneumonitis.
  • Patients must not have significant gastrointestinal disorders with diarrhea as a major symptom (e.g. Crohn's disease, malabsorption, etc.)
  • Patients must not have history of auto-immune condition requiring ongoing or intermittent systemic treatment in the past 2 years (i.e. with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Replacement therapy (e.g., thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment.
  • Patients with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, should have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification. To be eligible for this trial, patients should be class II or better.
  • Patients must not have any other concomitant serious illness or organ system dysfunction that in the opinion of the investigator would either compromise patient safety or interfere with the evaluation of the safety of the study drug.
  • Patients must not receive any other investigational agents during the course of therapy.
  • Women must not be pregnant or breast-feeding due to potential harm to the fetus or infant from cytotoxic chemotherapy and the unknown risk of MK-3475 (pembrolizumab). Patients must also not expect to conceive or father children from the time of registration, while on study treatment, and until at least 120 days after the last dose of study treatment. All females of childbearing potential must have a blood test or urine study within 72 hours prior to registration to rule out pregnancy. A female of childbearing potential is any woman, regardless of sexual orientation or whether they have undergone tubal ligation, who meets the following criteria: 1) has achieved menarche at some point; 2) has not undergone a hysterectomy or bilateral oophorectomy; or 3) has not been naturally postmenopausal (amenorrhea following cancer therapy does not rule out childbearing potential) for at least 24 consecutive months (i.e., has had menses at any time in the preceding 24 consecutive months).
  • Women of childbearing potential and sexually active males must use an accepted and effective method of contraception or abstain from sexual intercourse from time of registration, while on study treatment, and continue for 120 days after the last dose of study treatment.
  • Patient must have the ability to understand and the willingness to sign a written informed consent document.
  • Patients must meet the following laboratory values within 14 days of randomization:
  • ANC ≥ 1500/mm3
  • Platelets ≥ 100,000/mm3
  • Hgb > 8 g/dL (Note: Patient may be transfused to meet this criteria)
  • PT/INR ≤ 1.5
  • Or if patient on therapeutic anticoagulation with Warfarin, PT/INR ≤ 3.0
  • Patients must have adequate liver function as determined by the following tests obtained within 14 days of randomization:
  • Total Bilirubin ≤ 1.5 mg/dL
  • SGOT (AST) < 5X upper limit of normal (ULN)
  • SGPT (ALT) < 5X upper limit of normal ULN)
  • Patients must have adequate renal function as determined by the following tests obtained within 14 days prior to randomization: Calculated creatinine clearance ≥ 45ml/min to be eligible to receive pemetrexed Serum creatinine ≤ 1.5X institutional upper limit of normal (ULN)
  • Patients must not have a known history of active tuberculosis (TB).
  • Patients must not have a diagnosis of immunodeficiency or receive systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of protocol treatment.
  • Patients must not have received a live vaccine within 30 days prior to randomization. Seasonal flu vaccines that do not contain live virus are permitted. COVID-19 vaccination per guidelines for cancer patients is permitted and encouraged.
  • Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial.
  • For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable or on suppressive therapy, if indicated. Patients with a history of hepatitis C virus (HCV) infection must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load. Head and Neck Cancer (Arm 3)
  • Patient must have histologically confirmed recurrent/metastatic squamous cell carcinoma of the head and neck (HNSCC) (excluding SCC of salivary glands, nasopharynx and skin) that is considered incurable by local therapies. The eligible primary tumor locations include oropharynx, oral cavity, hypopharynx, and larynx. Unknown primary site will also be considered eligible.
  • Patients may have ANY PD-L1 expression Tumor Proportion Score (CPS) status. Tissue testing for PD-L1 IHC on samples demonstrating recurrent/metastatic disease is strongly recommended, though testing may be performed on initial diagnostic specimens. If PD-L1 expression CPS is unevaluable or the testing could not be completed, the patient will still be considered eligible.
  • Tumor expression of p16 by immunohistochemistry is highly desirable for patients with Oropharyngeal primaries. Positive p16 expression is defined as strong and diffuse nuclear and cytoplasmic staining in 70% or more of the tumor cells. If HPV status was previously tested using this method, no additional testing is required. If results are not available or are not possible patient will still be considered eligible. Note: Oral cavity, hypopharynx, and larynx cancer are not required to undergo HPV testing by p16 IHC as by convention these tumor locations are assumed to be HPV negative.
  • Patients must have measurable or non-measureable disease. The presence of malignant pleural fluid or bone disease alone is sufficient to satisfy this eligibility criterion. Baseline imaging assessments and measurements used to evaluate all measurable or non-measurable sites of disease must be done within 4 weeks prior to study registration. Tumor lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions.
  • Patient must be ≥ 18 years of age.
  • Patient must have an ECOG performance status 0-2.
  • Patients must NOT have received the following:
  • Prior systemic chemotherapy or immunotherapy for recurrent/metastatic head and neck squamous cell carcinoma. Patients treated with any prior checkpoint inhibitors for recurrent/metastatic head and neck cancer are ineligible. NOTE: Patients who have received prior chemotherapy or cetuximab with radiation for curative intent treatment of locally advanced head and neck cancer whose disease has progressed after at least 6 months will be eligible.
  • Methotrexate (MTX) given in low doses for non-malignant conditions with last dose at least 14 days prior to date of registration will be allowed. Other low dose chemotherapeutics for non-malignant conditions will be considered, but review by the study chair is required.
  • Patients who have endocrinopathies but are now stable on hormone supplementation and/or a daily prednisone dose of ≤ 10 mg (or equivalent doses of another glucocorticoid), will be permitted on this trial.
  • Patient must not have a severe infection within 4 weeks prior to randomization, including, but not limited to, hospitalization for complications of infection, bacteremia, or severe pneumonia. Patients must not have active tuberculosis.
  • Patient must not have a history of non-infectious pneumonitis requiring steroids at doses greater than or equal to 10 mg per day of prednisone or the equivalent on first line immunotherapy.
  • Patient must not have a history of solid organ transplantation or stem-cell transplant.
  • Patient must not be on immunosuppressive medication within 7 days prior to randomization except for: intranasal, inhaled, or topical steroids, local steroid injection, systemic corticosteroids at doses less than or equal to 10 mg per day of prednisone or the equivalent, or steroids used as premedication for hypersensitivity reactions.
  • Patient must not have an active autoimmune disease that requires systemic treatment within 2 years prior to randomization. Patients who are receiving replacement therapy for adrenal or pituitary insufficiency will not be excluded.
  • Patient must not have had a severe hypersensitivity reaction to any of the drug components used on this protocol or to chimeric or humanized antibodies or fusion proteins.
  • Patient must not have received any live vaccine within 30 days prior to randomization and while participating in the study. Live vaccines include, but are not limited to, the following: measles, mumps, rubella, chicken pox, yellow fever, rabies, BCG, and typhoid (oral) vaccine. Patients are permitted to receive inactivated vaccines and any non-live vaccines including those for the seasonal influenza and COVID-19 (Note: intranasal influenza vaccines, such as Flu-Mist® are live attenuated vaccines and are not allowed). If possible, it is recommended to separate study drug administration from vaccine administration by about a week (primarily, in order to minimize an overlap of adverse events).
  • Patient must not be pregnant or breast-feeding due to the potential harm to an unborn fetus and possible risk for adverse events in nursing infants with the treatment regimens being used. All patients of childbearing potential must have a blood test or urine study within 14 days prior to randomization to rule out pregnancy. A patient of childbearing potential is defined as anyone, regardless of sexual orientation or whether they have undergone tubal ligation, who meets the following criteria: 1) has achieved menarche at some point, 2) has not undergone a hysterectomy or bilateral oophorectomy; or 3) has not been naturally postmenopausal (amenorrhea following cancer therapy does not rule out childbearing potential) for at least 24 consecutive months (i.e., has had menses at any time in the preceding 24 consecutive months).
  • Patients must not expect to conceive or father children by using accepted and effective method(s) of contraception or by abstaining from sexual intercourse for the duration of their participation in the study and for 120 days after last dose of study therapy.
  • Patient must have the ability to understand and the willingness to sign a written informed consent document.
  • Patient must have adequate organ and marrow function as defined below (these labs must be obtained ≤ 14 days prior to protocol randomization):
  • Absolute neutrophil count (ANC) ≥ 1,500/mcL
  • Platelets ≥ 100,000/mcL
  • Hgb > 8 g/dL (Note: Patient may be transfused to meet this criteria)
  • Total bilirubin ≤1.5xULN OR Direct bilirubin ≤ULN for subjects with total bilirubin levels >1.5xULN
  • AST (SGOT)/ALT (SGPT) ≤ 2.5 × institutional ULN (< 5.0 x institutional ULN if hepatic metastases present)
  • Creatinine ≤ 1.5 x institutional ULN OR Measured or Calculated Creatinine Clearance ≥60 mL/min for subject with creatinine levels >1.5x institutional ULN
  • PT/INR ≤ 1.5
  • Or if patient on therapeutic anticoagulation with Warfarin, PT/INR ≤ 3.0
  • Patients with uncontrolled or symptomatic hypercalcemia (ionized calcium > 1.5 mmol/L, calcium > 12 mg/dL) must have their calcium levels corrected prior to randomization.
  • Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months of randomization are eligible for this trial.
  • For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated.
  • Patients with a history of hepatitis C virus (HCV) infection must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load.
  • Patients with treated brain metastases are eligible if follow-up brain imaging after central nervous system (CNS)-directed therapy shows no evidence of progression. Patients must not have untreated brain metastases or leptomeningeal disease.
  • Patients with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial.
  • Patient must not have significant cardiovascular disease (such as New York Heart Association Class II or greater cardiac disease, myocardial infarction, or cerebrovascular accident) within 3 months prior to randomization, or unstable arrhythmia or unstable angina at the time of randomization.
  • Patient must not receive any other chemotherapy, immunotherapy, antitumor hormonal therapy (excluding contraceptives and replacement steroids), radiation therapy, or experimental medications while on protocol treatment. Symptomatic lesions (e.g., bone metastases or metastases causing nerve impingement) amenable to palliative radiotherapy should be treated prior to randomization and patients must be recovered from the effects of radiation (there is no required minimum recovery period).
  • Patient must not have any other disease, metabolic dysfunction, physical examination finding, or clinical laboratory finding that contraindicates the use of the agents used in this protocol, may affect the interpretation of the results, or may render the patient at high risk from treatment complications.

Inclusion Criteria:

The patient must have an ECOG performance status of 0 or 1. Patients must have histologically/pathologically confirmed colon adenocarcinoma (T1-3, N1/N1c) with R0 resection accordingly to AJCC 8th edition criteria. NOTE: Patients with pathologic stages II or IIIC colon adenocarcinoma with R0 resection who have a commercially obtained Signatera™ ctDNA+ve assay result post-operatively meeting all timelines and eligibility requirements otherwise, are eligible for enrollment and inclusion in Cohort B. No radiographic evidence of overt metastatic disease within 28 days prior to study entry (CT with IV contrast or MRI imaging is acceptable and must include chest, abdomen, and pelvis). The distal extent of the tumor must be greater than or equal to 12 cm from the anal verge on colonoscopy or above the peritoneal reflection as documented during surgery or on pathology specimen (i.e., excluding rectal adenocarcinomas warranting treatment with chemoradiation). The patient must have had an en bloc complete gross resection of tumor (curative resection). Patients who have had a two-stage surgical procedure, to first provide a decompressive colostomy and then in a later procedure to have the definitive surgical resection, are eligible. The resected tumor specimen and a blood specimen from patients with Stage IIIA or Stage IIIB colon cancer must have central testing for ctDNA using the Signatera™ assay by Natera. NOTE: Patients with stage IIIA or IIIB colon cancer who otherwise meet eligibility criteria and have had ctDNA status checked with the Signatera™ assay as routine care outside of the study, are allowed to be enrolled, and will be retested and placed in either Cohort A or Cohort B depending on the central ctDNA testing result. NOTE: Patients with stage II or IIIC colon cancer who otherwise meet eligibility criteria and have had ctDNA status checked with the Signatera™ assay as routine care outside of the study AND have a ctDNA+ve result, are allowed to be enrolled. Patients will have central ctDNA testing, confirmed to be ctDNA+ve, and placed in Cohort B. Tumor must be documented as microsatellite stable or have intact mismatch repair proteins through CLIA-approved laboratory testing. Patients whose tumors are MSI-H or dMMR are excluded. The treating investigator must deem the patient a candidate for all potential agents used in this trial (5FU, LV, oxaliplatin and irinotecan). The interval between surgery (post-operative Day 7) and study entry must be no more than 60 days. Availability and provision of adequate surgical tumor tissue for molecular diagnostics and confirmatory profiling. Adequate hematologic function within 28 days before study entry defined as follows:
• Absolute neutrophil count (ANC) must be greater than or equal to 1500/mm3;
• Platelet count must be greater than or equal to 100,000/mm3; and
• Hemoglobin must be greater than or equal to 9 g/dL. Adequate hepatic function within 28 days before study entry defined as follows:
• total bilirubin must be less than or equal to ULN (upper limit of normal) for the lab and
• alkaline phosphatase must be less than 2.5 x ULN for the lab; and
• AST and ALT must be less than 2.5 x ULN for the lab. Adequate renal function within 28 days before study entry defined as serum creatinine less than or equal to 1.5 x ULN for the lab or measured or calculated creatinine clearance greater than or equal to 50 mL/min using the Cockroft-Gault formula for patients with creatinine levels greater than 1.5 x ULN for the lab. For Women Creatinine Clearance (mL/min) = (140 - age) x weight (kg) x 0.85 72 x serum creatinine (mg/dL) For Men Creatinine Clearance (mL/min) = (140 - age) x weight (kg) 72 x serum creatinine (mg/dL) HIV-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial. Pregnancy test (urine or serum according to institutional standard) done within 14 days before study entry must be negative (for women of childbearing potential only). Patients receiving a coumarin-derivative anticoagulant must agree to weekly monitoring of INR if they are randomized to Arm 1 or Arm 3 and receive capecitabine. Eligibility Criteria for Cohort A Arm-2 patients on Second Randomization Patient must have developed a ctDNA +ve assay during serial monitoring. Patient's willingness to be re-randomized affirmed. The patient must continue to have an ECOG performance status of 0 or 1. No radiographic evidence of overt metastatic disease. Pregnancy test (urine or serum according to institutional standard) done within 14 days before study entry must be negative (for women of childbearing potential only). Adequate hematologic function within 28 days before randomization defined as follows:
• Absolute neutrophil count (ANC) must be greater than or equal to 1500/mm3;
• Platelet count must be greater than or equal to 100,000/mm3; and
• Hemoglobin must be greater than or equal to 9 g/dL. Adequate hepatic function within 28 days before randomization defined as follows:
• total bilirubin must be less than or equal to ULN (upper limit of normal) for the lab and
• alkaline phosphatase must be less than 2.5 x ULN for the lab; and
• AST and ALT must be less than 2.5 x ULN for the lab. Adequate renal function within 28 days before randomization defined as serum creatinine less than or equal to 1.5 x ULN for the lab or measured or calculated creatinine clearance greater than or equal to 50 mL/min using the Cockroft-Gault formula for patients with creatinine levels greater than 1.5 x ULN for the lab. For Women Creatinine Clearance (mL/min) = (140 - age) x weight (kg) x 0.85 72 x serum creatinine (mg/dL) For Men Creatinine Clearance (mL/min) = (140 - age) x weight (kg) 72 x serum creatinine (mg/dL)

Exclusion Criteria:

Colon cancer histology other than adenocarcinoma (i.e., neuroendocrine carcinoma, sarcoma, lymphoma, squamous cell carcinoma, etc.). Pathologic, clinical, or radiologic overt evidence of metastatic disease. This includes isolated, distant, or non-contiguous intra-abdominal metastases, even if resected. Tumor-related bowel perforation. History of prior invasive colon malignancy, regardless of disease-free interval. History of bone marrow or solid organ transplantation (regardless of current immunosuppressive therapy needs). Bone grafts, skin grafts, corneal transplants and organ/tissue donation are not exclusionary. Any prior systemic chemotherapy, targeted therapy, or immunotherapy; or radiation therapy administered as treatment for colorectal cancer (e.g., primary colon adenocarcinomas for which treatment with neoadjuvant chemotherapy and/or radiation is warranted are not permitted). Other invasive malignancy within 5 years before study entry. Exceptions are colonic polyps, non-melanoma skin cancer or any carcinoma-in-situ. Synchronous primary rectal and/ or colon cancers. Patients with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, should have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification. To be eligible for this trial, patients should be class 2B or better. Sensory or motor neuropathy greater than or equal to grade 2, according to CTCAE v5.0. Blood transfusion within two weeks before collection of blood for central ctDNA testing. Active seizure disorder uncontrolled by medication. Active or chronic infection requiring systemic therapy. Known homozygous DPD (dihydropyrimidine dehydrogenase) deficiency. Patients known to have Gilbert's Syndrome or homozygosity for UGT1A1*28 polymorphism. Pregnancy or lactation at the time of study entry. Co-morbid illnesses or other concurrent disease that would make the patient inappropriate for entry into this study (i.e., unable to tolerate 6 months of combination chemotherapy or interfere significantly with the proper assessment of safety and toxicity of the prescribed regimens or prevent required follow-up). Ineligibility Criteria for Cohort A Arm-2 patients on Second Randomization Pregnancy or lactation at the time of randomization. No longer a candidate for systemic chemotherapy (FOLFOX, CAPOX, and mFOLFIRINOX) in the opinion of the treating investigator.