The long term side effects of adjuvant carboplatin for stage 1 seminoma

Abstract

5089 Background: Radiotherapy is associated with an increase of second cancer and cardiovascular disease. Because of difficulties in detecting recurrence on surveillance which can occur out to 10 years, this unit has developed Carboplatin as the treatment for these patients and this abstract summarises late events in these 3 cohorts. Methods: Radiation therapy consisted of para-aortic and pelvis treatment (3,000 cGy). This occurred between 1960 and 1978. Surveillance began in 1980 and Carboplatin studies in 1984 with 2 courses of 450 mg/m2 being standard until 1987 when 1 course AUC × 7 was introduced and with increased confidence became standard. Results: Seventy-eight patients were treated with radiotherapy (median follow up 17 years). Overall mortally was 24% at 20 years compared with expected 10%. Death from germ cell cancer was 4.0%, deaths from 2nd non-germ cell cancer were 13%, and deaths from other causes was 7.0%. For surveillance (n=110, median follow up 9.8 years) there were 1.7% deaths, with no germ cell or non-germ cell cancer related deaths., and 1.7% deaths due to non cancer. Carboplatin (n=186, median follow up 9.5 years 97>10 yrs, and 38 >15 yrs) was associated with 98% survival at 10 years with 0 deaths due to GCC (3% relapse all before 3 years) 1% due to second non-GCC cancer and 1% to other causes. Conclusion: The numbers of cases are too small to be absolutely confident of these figures. However, this data suggests there are no late relapses and no excess of cancer or cardiovascular deaths in the single agent carboplatin cohort. No significant financial relationships to disclose.