THE ABLATIVE EFFECT OF QUARTER DOSE BACILLUS CALMETTE-GUERIN ON A PAPILLARY MARKER LESION OF THE BLADDER

Abstract

Low dose bacillus Calmette-Guerin (BCG) for stage TaT1 transitional cell carcinoma of the bladder has been given in various studies with the aim of decreasing side effects while maintaining the same efficacy as full dose bacillus Calmette-Guerin. However, its application in clinical practice remains controversial. We examined the ablative activity and incidence of side effects of intravesical quarter dose BCG given for a papillary marker lesion of the bladder. Included in our study were 44 patients with primary or recurrent, multiple but no more than 10 lesions of stage pTaT1, grades 1 to 2 transitional cell carcinoma of the bladder. Intravesical treatment begun 14 days after the complete transurethral resection of all visible tumors except 1 marker lesion no larger than 1 cm. consisted of instillations of 30 mg. Connaught strain BCG diluted in 50 ml. saline once weekly for 6 consecutive weeks. Two weeks after the last instillation any residual tumor was completely resected. In cases of complete disappearance of the marker lesion deep biopsy of the tumor area was done. Urine cytology was also performed. There was a complete response in 27 of the 44 patients (61%), no response in 12 (27%) and progression to carcinoma in situ in 1 (2%), while the response was not evaluable in 4. Local side effects included dysuria in 54% of cases and macroscopic hematuria in 39%. Neither BCG induced infection nor BCG sepsis was observed. Quarter dose BCG has a clear ablative effect on superficial bladder cancer with a 61% response rate. Phase III trials are now required to compare its efficacy and toxicity to those of full dose BCG.