Preoperative Chemoradiotherapy for Locally Advanced Rectal Cancer: A Retrospective Analysis.

Purpose To evaluate the outcomes of patients with locally advanced rectal cancer (LARC) treated with preoperative chemoradiotherapy (CRT) at a community cancer center.  Methods A retrospective chart review was conducted for patients with biopsy-proven rectal adenocarcinoma treated with CRT between January 2017 and June 2020. Patients were excluded if there was metastatic disease (stage IV) at presentation, if curative resection was not planned, or if they received additional preoperative chemotherapy. Preoperative radiotherapy was typically 50.4 Gy in 28 fractions with concurrent capecitabine chemotherapy, followed by surgery six to eight weeks later. Postoperative adjuvant FOLFOX chemotherapy was typically recommended in suitable patients. Outcomes measured included surgical margin status, pathological complete response (pCR), local recurrence rate, distant metastases, cancer-specific survival, and overall survival. Results A total of 120 patients underwent preoperative CRT during this period. Seven patients did not undergo subsequent surgical resection. The pCR rate was 14%, and R0 resection (negative margins) was achieved in 93% of cases. The cumulative incidence of local recurrence was 6%, and distant metastases developed in 23% of patients. The most common metastatic sites were the liver and lungs. With a median follow-up of 28 months, Kaplan-Meier analyses demonstrated a 78% cancer-specific survival (CSS) and 75% overall survival (OS). Conclusion Preoperative CRT resulted in a 14% pCR rate, which was associated with high R0 (93%) and low local recurrence rates (6%). Distant metastatic recurrence rate remains a concern (23%).