Association of depressed mixed lymphocyte reactivity with the development of bladder carcinoma in patients with papillomas
Patients with bladder papillomas have an excellent overall prognosis, although approximately 10% of such patients develop frank bladder cancer. It is therefore important to devise methods for subclassifying bladder papillomas in an attempt to identify those patients at high risk for progression to carcinoma. The lymphoproliferative responses in 27 patients with bladder papillomas were tested in the mixed lymphocyte reaction (MLR). Patient responses were compared to those of normal individuals tested simultaneously. A relative proliferation index (RPI) was defined as a percent response relative to the mean normal response. A RPI less than 0.5 was defined as a depressed MLR and greater than 0.5 as a normal MLR. All patients were followed at three-month intervals for at least five years for the development of superficial or invasive bladder carcinoma. Of the 27 patients, 12 had a depressed MLR and 10/12 (83%) developed cancer within five years. Of the 15 patients with a normal MLR, only three developed bladder carcinoma. The number of papilloma patients surviving free of bladder carcinoma at five years was 12/15 (80%) with a normal MLR and 2/12 (17%) with a depressed MLR (P less than 0.01). Measurement of the MLR appeared to offer a useful adjunct in the evaluation of staging and biologic potential of bladder papilloma.