The Prognostic Implications of FIX and FLO Patterns in Mucinous Colon Carcinomas

Abstract

Purpose: Colon mucinous carcinomas (MUCs) have two morphological patterns: (i) glands lined by mucinous epithelium with direct contact to the stroma (FIX) and (ii) carcinoma cells floating in mucin (FLO). In this study, we evaluated the prognostic value of these patterns. Methods: Digital images were captured from the 38 MUC’s tissue sections. A grid with 140 points was laid over the computer screen. Totally, 100 points, falling on tumor cells floating in mucin (FLO patterned cells) or on cells contacting stroma (FIX patterned cells), were counted. Tumors were grouped according to the median value of the FIX patterned cells. Cases with more than this value were grouped as FIX and less were grouped as FLO cases. The prognostic value of FIX and FLO pattern was evaluated. Results: The median for FIX patterned cells was 66%, and the cases with lower values than this were grouped as FLO (N = 18; 47.37%), while the rest were grouped as FIX cases. There was no significant difference between FIX and FLO cases for overall survival cases (p = 0.167). For FIX cases, 62.7 and 51.3% of the patients were alive at second and third years, while this was 78.9 and 72.4% for the FLO group, respectively. Conclusions: This is the first study using a quantitative methodology depending on count pointing to evaluate FIX/FLO feature of MUCs to the best of our knowledge, although we could not observed any prognostic and clinicopathologic relationship statistically. This distinctive feature should be studied in larger cohorts with prognostic information, with a quantitative method, like the one that was applied in this study, in order to achieve strict conclusions.