IMPROVING THE SAFETY OF BCG IMMUNOTHERAPY BY BOSE REDUCTION

The preliminary results of a randomized, multicentre, prospective tria l conducted by the Spanish Oncology Group (CUETO) are presented. The p rimary aim of the trial was to determine whether or not lowering the d ose of bacillus Calmette-Guerin (BCG)I could reduce toxicity without c ompromising efficacy. From February 1991 to June 1992, 500 patients wi th superficial bladder cancer (TaG2-3, T1G1-3) entered the trial. Of t hese patients, 252 were included in group A (BCG, 81 mg) and 248 in gr oup B (BCG, 27 mg). There were no significant differences in clinical and pathological characteristics between the two groups. Following tre atment, significant differences arose between groups A and B in local severe toxicity (22.6 vs. 4.2%, respectively; p < 0.01). Systemic toxi city was more common in group A than in group B (p < 0.01): pulmonary effects (2.3 vs. 0.4%), fever (26.9 vs. 12.9%) and malaise (16.2 vs. 8 .4%), all p < 0.01. Regarding efficacy, 204 patients in group A and 21 0 in group B were evaluated after a mean follow-up of 18.6 months. No significant differences in recurrence rate (18.1 vs. 19.5%) or progres sion rate (2.4 vs. 4.8%) were found. However, in patients with superfi cial bladder cancer with high risk of recurrence and progression (carc inoma in situ and G3), caution must be exercised in selecting the dose .