PURPOSE: Mucinous adenocarcinomas account for about 10% of all colorectal cancers. This study aimed to investigate the prognostic impact of mucinous histologic subtype on oncologic outcomes in patients with colorectal cancer. METHODS: This retrospective study was performed at two large tertiary university hospitals. We analyzed the characteristics, prognostic factors, and survival of patients with colorectal cancer who were treated and followed up between 2000 and 2013. RESULTS: Totally, 144 of 1,268 patients with a colorectal adenocarcinoma (11.4%) had mucinous histologic subtype. Statistically significant results found in this research are as follows: Mucinous histologic subtype tended to present in younger patients and to have larger tumor size, higher histologic grade, higher node stage, larger number of positive nodes, and higher rate of perineural invasion compared to nonmucinous histologic subtype. On the univariate analysis, mucinous subtype was a prognostic factor for disease-free and overall survival. On the multivariate analysis, primary tumor location, node stage and lymphatic-vascular invasion were independent prognostic factors for the local control rate. Rectal tumor location, higher disease stage, tumor grade II, and presence of lymphatic-vascular invasion had negative influences on disease-free survival, as did rectal tumor location, higher disease stage and presence of lymphatic-vascular invasion on overall survival. CONCLUSION: Mucinous histologic subtype was associated with some adverse pathologic features in patients with colorectal cancer; however, it was not an independent prognostic factor for oncologic outcome.
Adenocarcinoma ; Adenocarcinoma, Mucinous ; Colorectal Neoplasms* ; Disease-Free Survival ; Hospitals, University ; Humans ; Mucins* ; Multivariate Analysis ; Prognosis ; Rectal Neoplasms ; Retrospective Studies ; Survival Rate ; Treatment Outcome

PURPOSE: Local recurrence is a common failure pattern in adenocarcinoma of the cecum. This study aimed to investigate the potential role of adjuvant radiation therapy on oncologic outcomes of patients with adenocarcinoma of the cecum. MATERIALS AND METHODS: This retrospective study was carried out at three large tertiary university hospitals. We analyzed the characteristics, prognostic factors, and survival of 162 patients with adenocarcinoma of the cecum that were treated and followed up between 2000 and 2013. All the patients had undergone a right hemicolectomy and received chemotherapy with (n = 48) or without (n = 114) adjuvant radiation therapy. RESULTS: The subjects were 65 females and 97 males with a median age of 56 years (range, 17 to 90 years) at diagnosis. The 5-year local control (LC), disease free survival (DFS), and overall survival (OS) rates were 72.7%, 57.2%, and 62.6% respectively. In a multivariate analysis, age, tumor stage, node stage, and adjuvant radiation therapy were determined to be independent prognostic factors. Age more than 55 years (hazard ratio [HR] = 1.0; 95% confidence interval [CI], 0.06–0.32; p = 0.003], T4 stage (HR = 6.8; 95% CI, 3.07–15.36; p < 0.001), node positive disease (HR = 4.2; 95% CI, 1.94–9.13; p < 0.001), and the absence of adjuvant radiation therapy (HR = 3.0; 95% CI, 1.39–6.46; p = 0.005) had a negative influence on OS. CONCLUSION: Adjuvant radiation therapy significantly improves DFS and OS in patients with adenocarcinoma of the cecum.
Adenocarcinoma ; Cecum ; Colon ; Diagnosis ; Disease-Free Survival ; Drug Therapy ; Female ; Hospitals, University ; Humans ; Male ; Multivariate Analysis ; Prognosis ; Recurrence ; Retrospective Studies