Prognostic significance of presence of any mucinous component in curatively resected stage II and III colorectal cancer patients who received adjuvant treatments: Data from a single tertiary center.

Abstract

e14660 Background: Mucinous adenocarcinoma colorectal cancer (CRC) is defined as presence of more than 50% mucinous component and its prognostic significance is debatable. We analyzed the prognostic importance of positivity of any mucinous component in early stage adenocarcinoma patients who were operated and received adjuvant treatments in a single tertiary cancer center. Methods: Data from charts of early stage CRC patients curatively treated between January 1998-December 2009 in our clinic was retrospectively analyzed. Cases with any degree of mucine presence in final pathology reports were noted (including mucinous adenocarcinomas). Adjuvant treatments were either 5-FU or oxaliplatin based regimens. All rectal carcinoma patients received postoperative radiotherapy. Survival analyses were made by Kaplan-Meier estimator, and independent factors of survival were tested with Cox regression test. Survival data of subgroups were compared with log-rank test. Results: 532 patients (45% female) were analyzed. Median follow-up was 36 months. Median age at diagnosis was 62 years (24-84). Fifty-four percent of patients had rectal primary (n=292). Presence of any mucinous component was found in 94 patients (17.7%). There was a close relation between mucine presence and T stage (p=0.0001) or tumor grade (p=0.0001). There was no statistical relation between presence of mucine and lymphatic invasion, vascular invasion, or perineural invasion. Five-year disease-free survival for mucine (+) and mucine (-) tumors were, 45.7% and 61.4%, respectively (p=0.031). Five -year overall survival of mucine (+) tumors was worse than mucine (-) tumors (65% vs. 74%, p=0.004). Conclusions: Presence of any mucinous component in early stage CRC appears to be an important bad prognostic feature in our patient group, which was not previously reported in the literature to our knowledge. This “context specific prognostic property” of presence of any mucinous component might serve as a stratification factor for further adjuvant CRC studies.