Objective. To compare the efficacy of three different doses of intravesical interferon α-2b (IFNα-2b) in reducing recurrence and progression rates in superficial grade II, transitional cell carcinoma (TCC). Patients and methods. Eighty-nine patients with primary or recurrent TCC stage Ta/T1, grade II, were randomly allocated into four groups after transurethral resection (TUR) of the tumour. Group A (20 patients) received no further treatment, serving as the control group; group B (22 patients) received 40 MU of IFNα-2b, group C (24 patients) 60 MU and group D (23 patients) 80 MU. The instillations started within 48-72 h after TUR and were performed weekly for 2 months, bimonthly for the next 4 months and thereafter monthly for 6 months. The patients were followed for 36 months. The four groups were compared for the number of recurrences (simple recurrence rate), progression in stage, disease-free interval and recurrence rate per 100 patient-months. Results. During the follow-up, 22 patients had recurrence (13, eight, seven and five in groups A to D, respectively). The simple recurrence rate was 65% for group A, compared with 36% (P = 0.06), 29% (P < 0.05) and 22% (P < 0.01) for groups B, C and D, respectively. The differences in simple recurrence rates between the groups treated with IFNα-2b were not statistically significant. Eleven patients experienced progression in stage, with six, three, one and one in groups A to D, respectively. The differences were statistically significant only between groups A and C (P < 0.05) and groups A and D (P < 0.05). The disease-free interval was 15 months for group A, compared with 21.4 (P < 0.05), 26.1 (P < 0.001) and 30 months (P < 0.001) for groups C to D, respectively. The disease-free intervals of the groups treated with IFNα-2b were significantly different between all patients in groups B and D (P < 0.01) and only for those with stage T1 between groups C and D (P < 0.01). Finally the recurrence rate per 100 patient-months was 2.91, 1.19, 0.88 and 0.63 for groups A to D, respectively (all P < 0.001). The results were always in favour of the patients treated with the high dose, the only exception being the difference between groups C and D (P = 0.026). No side-effects of the drug were noted, nor was any adverse reaction reported from any patient. Conclusion. These results show a significant advantage for adjuvant intravesical IFNα-2b treatment over TUR alone for the 36 months of follow up and indicate that IFNα-2b can modify the clinical course of superficial TCC at least in the short term. The appropriate dose was apparently 80 MU, for although 40 MU was better than TUR alone, it was less effective than 60 MU and 80 MU; the 80 MU dose was slightly better than 60 MU and thus this regimen is recommended.
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/aggregator-openarchives/portal/institutions/uoa
