DESMOPLASTIC RESPONSE IN BIOPSY SPECIMENS OF EARLY COLORECTAL-CARCINOMA IS PREDICTIVE OF DEEP SUBMUCOSAL INVASION

The aim of this study was to evaluate the role of histopathology of bi opsy specimens in predicting depth of infiltration in early colorectal carcinomas before treatment. METHODS: Early colorectal carcinomas tha t had been resected surgically or endoscopically between 1984 and 1995 were analyzed. Histopathologic findings, including differentiation of adenocarcinoma and a desmoplastic response were investigated. RESULTS : One hundred nine early colorectal carcinomas consisted of 73 lesions of carcinoma in situ, 13 submucosal carcinomas with minimum invasion, 8 lesions with moderate invasion, and 15 lesions with deep invasion. Of 73 carcinoma in situ lesions, 72 (approximate ly 99 percent) showed well-differentiated adenocarcinomas and no desmoplastic response. Twe lve (92 percent) of 13 submucosal carcinomas with minimum invasion als o revealed well-differentiated adenocarcinoma without a desmoplastic r esponse. Sixty-three percent (5/8)of lesions with moderate invasion re vealed well-differentiated adenocarcinoma. None of the lesions had a d esmoplastic response. hmong lesions with deep invasion, 73 percent (11 /15) demonstrated moderately differentiated adenocarcinoma, and 11 les ions had a prominent desmoplastic response (73 percent: P < 0.01). CON CLUSIONS: These results suggest that if histopathologic findings of bi opsy specimens taken from them before treatment demonstrated adenocarc inoma associated with a desmoplastic response, the lesions had at leas t deep invasion carcinomas. These lesions should be resected surgicall y. Submucosal carcinomas with minimum invasion, which have no desmopla stic response, could be treated endoscopically.