Patterns of recurrence in patients achieving pathologic complete response after neoadjuvant chemoradiotherapy for rectal cancer.

PURPOSE: The aim of this study was to characterize the patterns of recurrence in patients achieving pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (CRT) for locally advanced rectal cancer.

METHODS: Patients with locally advanced rectal cancer treated with neoadjuvant CRT and who achieved pCR from January 2004 to December 2012 were collected. The primary outcome measurement was the patterns of recurrence.

RESULTS: Among 195 patients who achieved pCR, 18 developed recurrence. Furthermore, local recurrence occurred in 1.5% of patients (3/195), while distant metastases occurred in 7.7% of patients (15/195), which included 7 lung metastases, 1 liver metastasis, and 8 metastases in other locations.

CONCLUSIONS: Our study indicated that patients achieving pCR following neoadjuvant CRT have a favorable prognosis, with distant metastases predominating in all recurrences. Among patients with distant metastases, non-liver metastases were the predominant pattern.