Clinical staging of rectal cancer.

The gross and microscopic pathologic features of 167 rectal cancers were reviewed and the size, morphology and degree of differentiation correlated with the histologic Dukes' classification. A diagnosis of Dukes' A adenocarcinoma was made in 32 percent of all rectal cancers and in 70 percent of nonulcerated partly or well differentiated cancers that did not exceed 5 cm in greatest diameter. The incidence of Dukes' A lesions in patients meeting these criteria is similar to the survival rates reported after local excision, electrocoagulation and endorectal radiation. A prospective study comparing the results of local treatment with radical resection in selected patients is recommended.