Organ Preservation in the Treatment of Stage II and III Rectal Cancer.

A 65-year-old man underwent colonoscopy to evaluate rectal bleeding and was found to have a low rectal mass. Biopsy revealed moderately differentiated microsatellite stable adenocarcinoma. The tumor was palpable at the fingertip in the anterior rectum with the inferior border 5 cm from the anal verge by rigid proctoscopy. CEA was 0.8 ng/mL. CT imaging of the chest, abdomen, and pelvis showed no evidence of distant metastases. MRI confirmed a 5-cm mass with one 8-mm mesorectal lymph node metastasis and no extramural venous invasion. The tumor penetrated the mesorectal fat to a depth of 4 mm, and the circumferential margin was estimated to be 1 mm from the tumor (). He was presented at the multidisciplinary tumor board conference and interviewed and examined at the multidisciplinary clinic. He was dismayed at the prospect of his surgical options, a low anterior resection versus abdominoperineal resection, and wished to keep the options for organ preservation available. Standard long-course chemoradiation was initiated, with resolution of his bleeding after 2 weeks. He then completed 6 cycles of folinic acid, fluorouracil, and oxaliplatin (FOLFOX) chemotherapy (consolidation total neoadjuvant therapy (TNT)). The tumor was no longer palpable on office examination. A complete clinical response (cCR) was confirmed by flexible sigmoidoscopy () and MRI (). He was entered into the nonoperative management program with intense surveillance scheduling and has no evidence of recurrent disease almost 2 years after completion of TNT.