Anish Kuttappan Soman 1 , Binitha Tresa Thomas 2 , Rema Padanayil Lekshmikutty 3 , Nabeel Yahia 4 , Preeya Vasanthakumary

BACKGROUND Fluorouracil (5-FU) based chemoradiotherapy represents the standard treatment option for the preoperative treatment of advanced rectal cancer. Capecitabine is an oral precursor of 5-FU with the advantage of delivering the chemotherapy in an outpatient setup. NSABP R-04 & a German phase 3 trial by Hofheinz et al showed that Capecitabine was equivalent to 5-FU. The primary objective of this study was to evaluate pathological response (PR), clinical & surgical outcomes of stage II & III patients treated with chemoradiation with Capecitabine. The secondary objective was to evaluate toxicity and compliance to treatment. MATERIALS AND METHODS This single arm prospective study included 35 patients with stages II & III adenocarcinoma of rectum who after evaluation were treated with pelvic radiotherapy and concurrent Capecitabine. Toxicities were graded using RTOG scoring criteria. Clinical response was assessed after EBRT completion, and patients were referred for surgery after 4-6 weeks. Pathologic response and completeness of resection were assessed from the histopathology report. RESULTS Growth located within 5 cm from anal verge was seen in 24 (68.5%) patients and 6 were inoperable upfront. All patients completed the intended preoperative treatment and 88.6% did not have any toxicity related break in RT. Clinical response was seen in 80% of patients after Chemoradiation. Out of 35 treated 80% of them underwent surgery. APR was performed in 64.2% and 35.7% had LAR. Out of 6 upfront inoperable patients, 3 were converted to operable. Out of 23 APR cases, 7 were converted to anterior resection (30.4%, p=0.046). 96% of operated patients had an R0 resection, including all the 3 upfront inoperable patients. Minimal pathologic response was seen in 89.2% of patients and 7.14% had complete pathologic response. There were no Grade 4 or 5 toxicities. Only 2.9% had a Grade 3 event. 45.7% had maximum of Grade 1 events and 48.6% had maximum of Grade 2 events. CONCLUSION Chemoradiation with concurrent Capecitabine in Stage II and III Ca rectum results in good clinical response and modest pathologic response. It provides good surgical outcome in terms of complete resection and conversion to operability and results in sphincter-sparing resection for low lying tumours. Treatment is well tolerated with good patient compliance and acceptable levels of toxicity and also facilitates treatment on an outpatient basis.