Analysis by Step Sectioning of Early Invasive Bladder Cancer with Special Reference to G3·pT1 Disease

Eighty cases of cystectomized and step‐sectioned pT1 transitional cell carcinomas of various grades were analyzed. During the same period, 30 consecutive cases of pT2 carcinomas were also cystectomized and examined for comparison. This is a cross‐sectional study of a variety of cases of bladder cancer, designed to delineate the characteristics of G3·pT1 disease. Tumors in this series had a full set of various pathological findings; grades 1 to 3, stages Ta‐T1‐T2, papillary‐papillonodular‐nodular tumor configuration, α‐β‐γ type of invasion, presence of lymphatic and venous involvement, and presence of associated carcinoma in situ/ dysplasia. There is a distinct tendency of stepwise disease progression, such as grade 1→3, stage T1→T2, papillary→nodular configuration, and α→γ invasion, these factors being mutually related. We noted a similarity between tumor groups containing G3 component, such as G2‐3·pT1, G3 >2 ·pT1, G3·pT1, G1‐3·pT2, and G3·pT2. These tumors are different from groups such as G1‐2·pT1, G2·pT1 and G2 >3·pTl in terms of tumor configuration and type of invasion. As regards pT1 having G3 components, early cystectomy seems to be the surest treatment. Whenever one adopts a conservative policy in treatment of these tumors, extreme care should be taken to monitor tumor progression.