THE IMPORTANCE OF THE DEPTH OF INVASION IN STAGE T1 BLADDER-CARCINOMA- A PROSPECTIVE COHORT STUDY

Purpose: We studied the depth of invasion in the lamina propria in all patients with primary stage T1 bladder cancer in a geographical regio n and related the findings to the long-term prognosis. Materials and M ethods: All 121 primary stage T1 tumors diagnosed in western Sweden be tween 1987 and 1988 were analyzed with respect to the depth of invasio n in relation to the lamina muscularis mucosae. All clinical records w ere reviewed in 1994 and 1995. Results: More than 90% of the histopath ological specimens could be separated into superficially (pT1a) or dee ply (pT1b) invasive stage T1 tumors. Grade 3 tumors were significantly more common among patients with stage pT1b disease (79 versus 40%, p < 0.001). Patients with stage pT1b grade 3 cancer had a higher progres sion rate (58 versus 36%, p > 0.05) and an almost doubled risk of dyin g of bladder carcinoma compared to those with stage pT1a grade 3 disea se (45 versus 23%, p > 0.05). Carcinoma in situ at the primary operati on was associated with an impaired prognosis in patients with grade 3 tumors regardless of the depth of invasion in the lamina propria. Conc lusions: The prognosis is poor in patients with deep lamina propria in vasion (stage pT1b) treated with transurethral resection alone. Patien ts treated with radical cystectomy had excellent survival regardless o f the depth of invasion in the lamina propria. Radiotherapy was associ ated with poor survival.