Prognostic Comparison between Mucinous and Non-mucinous Rectal Adenocarcinoma

Background: We aimed to analyze the prognostic impact of mucinous and non- mucinous rectal adenocarcinoma with stage II and III rectal carcinoma treated with radical surgery plus (neo) adjuvant chemoradiotherapy and evaluate disease-free (DFS) and overall survival (OS). Method: We conducted this retrospective study on patients with pathologically proven stage II/III rectal carcinoma and treated in the Department of Clinical Oncology and Nuclear Medicine, Mansoura University Hospital between January 2008 and December 2013. We designed a clinical abstract sheet and reviewed all cases in terms of history, clinical assessment, investigations done on the patients, and pathological reports including all the details, and treatment modalities, namely neoadjuvant and adjuvant. Results: The median DFS for non-mucinous adenocarcinoma (NMC) was beyond 60 months, while that for mucinous adenocarcinoma (MA) was 24 months (P=0.008). The median OS for NMC was beyond 60 months; whereas, the mean OS of MA was 25 months (P=0.002).Therefore, the difference between both groups was statistically significant regarding DFS and OS. Pathological subtype was the only statistically significant independent predictor in the three-year DFS. However, pathological subtype and lymph-vascular invasion were statistically significant independent predictors in the three-year OS. Conclusion: Histological subtype was an independent prognostic factor for both DFS ans OS in patients with stages II and III rectal carcinoma.