Althausen A F, Prout G R, Daly J J
J Urol. 1976 Nov;116(5):575-80. doi: 10.1016/s0022-5347(17)58916-8.
We evaluated 129 patients with low grade, low stage transitional cell carcinoma of the bladder with a minimum followup of 5 years. In addition to the phenomena recognized as indicators of a serious clinical problem (grade greater than I, rapid recurrence, multiple tumors and lamina propria invasion) the identification of carcinoma in situ and/or atypia in normal, incidentally resected mucosa adjacent to the tumor was found to be a positive predictor for subsequent muscle invasion. Ten of 12 patients with carcinoma in situ and 9 of 25 patients with atypia were among 39 who experienced invasion.