Mucinous adenocarcinoma showing different clinicopathological and molecular characteristics in relation to different colorectal cancer subgroups.
BACKGROUND
Mucinous adenocarcinoma (MAC) is frequently reported to be associated with patients of young-age sporadic colorectal cancer (YSCC) and hereditary nonpolyposis colorectal cancer (HNPCC). This study is aimed to investigate whether the clinicopathological characteristics of MAC of HNPCC patients are distinct from those of YSCC patients.


METHODS
Eighty-two HNPCC and 68 YSCC patients recorded in the colorectal cancer registry of Chang Gung Memorial Hospital at Linkou, Taiwan, between January 1, 1995 and December 31, 2001 were included in this study. Clinicopathological and molecular variables of MAC and non-MAC of HNPCC and YSCC patients were compared accordingly.


RESULTS
Compared to non-MAC, MAC significantly showed higher frequencies of poor differentiation (32% vs. 8.2%, p = 0.001), advanced tumor stage (76% vs. 47%, p = 0.002), loss of mismatch repair protein (MMR) expression (74% vs. 44%, p = 0.023), and increased MUC2 expression (98% vs. 61%, p < 0.001). MAC of HNPCC patients showed predominant right-sided colon involvement, whereas MAC of YSCC patients displayed predominance in the left colon (79% vs. 22%, p = 0.001). Among the non-MAC counterparts, more differences were detectable including tumor stage, loss of MMR expression, and increased MUC1 expression. Furthermore, both MAC and non-MAC of YSCC patients showed higher frequencies of advanced tumor stage (81% vs. 62%, p = 0.072). In contrast, the incidence of loss of MMR expression in MAC and non-MAC of HNPCC patients is not significantly different (86% vs. 70%, p = 0.323).


CONCLUSIONS
Significantly different tumor localization was observed between mucinous YSCC (left colon predominance) and mucinous HNPCC (right colon predominance).
Chiang
J M
JM
Division of Colon and Rectal Surgery, Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Lin-Kou, Taiwan. jmjiang@adm.cgmh.org.tw
Yeh
C Y
CY
Changchien
C R
CR
Chen
J S
JS
Tang
R
R
Chen
J R
JR
D002288:Adenocarcinoma, Mucinous / Q000378:metabolism* / Q000473:pathology*; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000145:classification* / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology*; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000378:metabolism / Q000473:pathology; D053843:DNA Mismatch Repair; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D055815:Young Adult
D009077:Mucins