Total Neoadjuvant Therapy With mFOLFOX and Short-course Radiation in Resectable Rectal Cancer

Eligibility Criteria

• * Pathologic diagnosis of adenocarcinoma of the rectum (diagnosis by tissue biopsy) within 90 days prior to registration. At least a portion of the tumor must be located below the peritoneal reflection or begin within 12 cm of the anal verge on flexible endoscopy
• * Clinically staged (AJCC 8th ed.) T3-4 N0 M0 or T any N1-2 M0 based upon the following minimum diagnostic workup:
• * Colonoscopy, unless patient presents with an obstructing lesion
• * Within 30 days prior to registration:
• * History/physical examination
• * Imaging to exclude distant metastases: either contrast-enhanced CT of the chest, abdomen, and pelvis or whole-body PET-CT or MRI
• * Pelvic MRI (preferred) or transrectal ultrasound (TRUS) for T staging
• * ECOG Performance Status ≤1
• * Age ≥ 18 years
• * Adequate bone marrow function defined as follows:
• * Absolute neutrophil count (ANC) ≥ 1,200 cells/mm3
• * Platelets ≥ 100,000 cells/mm3
• * Hemoglobin ≥ 8.0 g/dL (Note: The use of transfusion or other intervention to achieve Hgb ≥8.0 g/dL is acceptable.)
• * Adequate liver and renal function defined as follows:
• * AST and alkaline phosphatase \< 2.5 x upper limit of normal (ULN)
• * Bilirubin ≤ 2.5 ULN
• * Calculated creatinine clearance (CrCl) \> 30 mL/min using Cockcroft-Gault formula as calculated by the standard Cockcroft-Gault equation using age, actual weight, creatinine, and gender
• * Must be deemed a candidate for curative resection by the surgical oncologist who will be performing the operation
• * Women of childbearing potential (WCBP) must have a negative serum pregnancy test performed within 7 days prior to the start of chemotherapy.
• * WCBP and men must agree to use a medically accepted form of birth control during the treatment and for 3 months following completion of chemotherapy.
• * Ability to understand and the willingness to sign a written informed consent document.
• * Prior RT that would result in overlap of RT fields with the planned study treatment
• * Clinically significant cardiac disease, including major cardiac dysfunction, that in the opinion of the treating medical oncologist would preclude them from receiving systemic therapy with 5-fluorouracil, leucovorin or oxaliplatin.
• * Serious (ie, ≥ grade 3) uncontrolled infection
• * Pulmonary or respiratory condition that, in the opinion of the treating medical oncologist would preclude them from receiving systemic therapy with 5-fluorouracil, leucovorin or oxaliplatin.
• * Major surgery within 28 days of study enrollment (other than diverting colostomy)
• * History of inflammatory bowel disease (eg, Crohn's disease, ulcerative colitis) requiring significant intervention (eg, hospitalization, surgery, immunosuppressive medications) that would, in the opinion of the investigator, preclude study therapy
• * Prior known allergic reaction to 5-fluorouracil, leucovorin, or oxaliplatin
• * Known dipyrimidine dehydrogenase deficiency (DPD)
• * Any evidence of distant metastases (M1)
• * Pregnant or breast feeding
• * Medical, psychological, or social condition that, in the opinion of the investigator, may increase the patient's risk or limit the patient's adherence with study requirements