Macroscopic typing with wall stricture sign may reflect tumor behaviors ofadvanced colorectal cancers

No appropriate macroscopic classification of advanced colorectal cancers (A -CRC) is available for assessing their tumor behavior. In the present study , A-CRC were classified macroscopically as either stricture or nonstricture type, and the differences in clinicopathological features, mode of recurre nce, and prognosis between the two types were investigated. The subjects we re 166 patients with A-CRC invading beyond the muscular layer who had under gone curative surgical resection. Fresh resected specimens from these patie nts were used for the study. The A-CRC were classified as of stricture or n onstricture type according to whether or not they showed marked fold conver gence and/or stricture of the intestinal tract (more than 30% wall shrinkag e) that had the appearance of a "bow tie". Of the 166 A-CRC, 47 (28%) were classified as stricture type. This type was significantly more frequent in the colon (37%; 37/101) than in the rectum (15%; 10/ 65) (P = 0.003). The s tricture type was more frequently associated with an abundance of fibrosis than the nonstricture type (76%; 28/37 vs 39%; 25/64 in colon; P < 0.001; 1 00%, 10/10 vs 42%, 23/55 in rectum; P < 0.001). The recurrence rate was als o higher in the stricture type than in the non-stricture type in both the c olon (51%, 19/37 vs 17%, 11/64; P = 0.003) and rectum (80%, 8/10 vs 38%, 21 /55; P = 0.01). The time to recurrence was significantly shorter for the st ricture type in both the colon (P < 0.001) and rectum (P = 0.02). These res ults indicate that the macroscopic typing of A-CRC according to the presenc e or absence of wall stricture sign may reflect their tumor behavior, altho ugh this behavior appears to be complex and related to tumor progression. T his classification could be important clinically to assess tumor behavior i n a simple way.