Prognostic implication of mucinous histology in colorectal cancer patients treated with adjuvant FOLFOX chemotherapy

Abstract

Background:There have been controversies in prognostic impact of mucinous histology on colorectal cancer, and its implication in patients treated with adjuvant 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) is unclear.Methods:Stage II and III colorectal cancer patients who underwent curative resection followed by adjuvant FOLFOX were included. Patients were grouped according to the mucinous content: >50%, mucinous adenocarcinoma (MAC); <50%, adenocarcinoma with intermediated mucinous component (AIM); and without any mucinous component, non-MAC (NMA). Clinicopathological features and disease-free survival (DFS) were compared.Results:Among a total of 521 patients, 27 patients (5.2%) had MAC, 41 patients (7.9%) had AIM, and 453 patients (86.9%) had NMA. Mucinous adenocarcinoma and AIM had higher frequency of proximal location and microsatellite instability, but lower frequency of angiolymphatic invasion. Disease-free survival was significantly worse in the MAC compared with NMA (3-year DFS 57% and 86%, respectively; P<0.001) and AIM (3-year DFS 87%, P=0.01 vs MAC). Multivariate analysis revealed MAC as an independent negative prognostic factor of DFS (adjusted hazard ratio 7.96, 95% confidence interval 3.76–16.8).Conclusion:Adenocarcinoma with intermediated mucinous component and MAC have distinct clinicopathological features compared with NMA. Mucinous adenocarcinoma has an adverse prognostic impact on stage II or III colorectal cancer treated with adjuvant FOLFOX.

Association between mutations of critical pathway genes and survival outcomes according to the tumor location in colorectal cancer

“…In addition, gene‐expression profiles are different for proximal colon cancer and distal cancer . In line with these findings, genetic and epigenetic data show that proximal CRC and distal CRC develop through distinct molecular pathways . Proximal CRC shows higher rates of a mucinous histology, MSI‐H, a CpG island methylator phenotype, KRAS mutations, phosphatidylinositol‐4,5‐bisphosphate 3‐kinase catalytic subunit α ( PIK3CA ) mutations, and BRAF mutations in comparison with distal CRC .…”

Inverse effect of mucinous component on survival in stage III colorectal cancer

“…The MAC was observed in only 16 (3.7%) of the 425 patients with stage III CRC. The incidence of MAC is greater in North American and Italian populations than in Korean or Japanese populations, which is suggestive of ethnic differences . The primary limitation to the present study is the small number of patients with mucinous histology and those treated with a combination of L‐OHP and 5‐FU chemotherapy, which hampered part of the statistical analyses, including retrospective analyses.…”

Sidedness is prognostic in locoregional colon cancer: an analysis of 9509 Australian patients

“…Perhaps more importantly, there are also marked differences in the molecular profile between these tumours [25]. RsCC has a higher rate of BRAF mutations and high microsatellite instability (MSI-H), both which have established prognostic importance, with MSI-H tumours shown to have a favourable prognosis, and BRAF a strong poor prognostic marker in non-MSI-H but not in MSI-H tumours [22, 23, 26, 27]. In addition even within MSI-H tumours there are known differences in prognosis, with hereditary MSI-H colon cancers shown to have a better survival than sporadic cases [28].…”