Organ Preservation in Early Rectal Cancer Patients

This is a single arm phase II study of neoadjuvant chemotherapy followed by local excision and post-operative chemoradiotherapy in patients with early stage, low rectal adenocarcinoma. After completion of pre-treatment tests/procedures (including pelvic MRI/ERUS; MRI is mandatory at baseline and other imaging is encouraged) and confirmation of eligibility, systemic therapy with FOLFOX will be administered for 12 weeks. 2 to 4 weeks after the chemotherapy, restaging of the primary tumor will be done to evaluate response to therapy (Pelvic MRI and /or sigmoidoscopy). Patients with disease progression or inadequate response to chemotherapy to allow local excision will continue with evaluation and treatment per the current standard of care (chemoradiation followed by TME). These patients will be considered failures for the primary endpoint of the study. Patients who respond to the neoadjuvant chemotherapy will proceed with local excision (open, TEMS or TAMIS), 6-12 weeks after the completion of neoadjuvant chemotherapy, followed by 5-FU based chemoradiotherapy 4-12 weeks after local excision. Patients with positive margins at the time of local excision will also be treated as per standard of care and will be considered as failures. Number of patients who can undergo successful local excision with this approach will define the success of the strategy. After chemoradiation therapy post local excision, patients will be followed closely every 3 months for the first 3 years and then every 2 months for the next 2 years (history/physical, CEA and pelvic MRI). Patients who are deemed failures for the primary end-point will be followed as per standard of care, off-study.