The practical use of tumor marker determination in bladder washing specimens. Assessing the urothelium of patients with superficial bladder cancer
Bladder washing specimens from 81 patients with recurrent multifocal superficial bladder cancer were evaluated for DNA profile by flow cytometry and cell-surface blood group (ABH) antigen reactivity by a modified specific erythrocyte adherence test. The study was conducted in a prospective, blind, nonrandomized fashion. Fifteen patients were treated with transurethral resection (TUR) alone and 66 with TUR and intravesical administration of bacillus Calmette-Guerin weekly for 6 weeks (TUR + BCG). Among the patients treated with TUR only, there was a notably greater rate of tumor recurrence and progression in patients with unfavorable tumor markers (aneuploidy and ABH-negative reactivity) than in those with favorable markers (diploidy and ABH-positive reactivity). The difference was less striking in patients treated with BCG, which reduced the frequency of recurrence or progression at 30 months from 87% to 44% and from 60% to 23%, respectively. This favorable effect of BCG was virtually confined to patients with initially favorable markers and to those whose initially unfavorable markers became favorable during BCG administration. Aneuploidy and negative ABH are phenotypic expressions of undifferentiation that can forecast the potential of the urothelium to form new tumors and predict invasion. To an extent, these markers are independent of the grade and stage of the disease. BCG can induce prognostically favorable conversion of the markers expression. Lack of such conversion indicates lack of response to BCG and should be regarded as evidence of persistent disease even if conventional methods do not reveal it. Therefore, sequential determination of markers is useful in monitoring patients with superficial bladder cancer treated with intravesical BCG.