Carcinoma in situ of the urinary bladder--the Singapore experience

Carcinoma in situ of the urinary bladder has been described since 1952. However, it was not well recognised as a clinical entity until recently when we are more aware of its clinical significance, that a large proportion progresses to muscle invasive cancer and becomes life threatening, and therefore more aggressive management is needed. From 1980 to 1984 over a period of 5 years, we studied the records of 130 patients with transitional cell carcinoma of the urinary bladder. Eighty-two (63%) were staged as superficial carcinoma while 48 (37%) were diagnosed as muscle invasive cancer (Tables II, III & IV). Out of the 82 cases of superficial carcinoma, 12 (11%) were found to have associated carcinoma in situ of the bladder. Diagnosis depends on a high index of suspicion, urinary cytology and biopsies of not only the obvious papillary or solid tumours but also any abnormal bladder mucosa and random bladder biopsy. Management is a problem and controversial. We have been using intensive intravesical chemotherapy with thiotepa and mitomycin, and if there is evidence of deep muscle invasion, then more aggressive therapy such as cystectomy would be advised. Management of these 12 cases and the problems we encountered are discussed.