ORLANDO, FL (UroToday) - A group of investigators from the UK sought to estimate the risk of bladder cancer (BCa) after childhood cancer, and explore whether cases were originally treated with cyclophosphamide (CPM) or radiotherapy. The analysis used the British Childhood Cancer Survivor Study (BCCSS), which consists of 17,981 individuals diagnosed with cancer 5years. Ascertainment of BCa was through the National Health Service Central Register. Medical, social and treatment information was obtained from BCCSS records.

Cohort Analysis:

To 31/12/04, 19 BCa were observed. The mean follow-up subsequent to 5y survival was 18.9 years. 5.3 times the number of BCa that would be expected were observed. The absolute excess risk (AER) for BCa was 0.5 cases/10,000 survivors/year (95% CI: 0.2-0.7). The cumulative percentage (95% CI) of survivors affected 20, 30, 40, 50y subsequent to first diagnosis were: 0.02%; 0.08%; 0.37%; and 0.71%. Significantly higher standardized incidence ratios (SIRs, the ratio observed to expected cancers) were seen for survivors: diagnosed with retinoblastoma, leukemia, non-Hodgkin's lymphoma (NHL) and soft tissue sarcoma, originally diagnosed 0-4y, and with the shortest follow-up i.e. 5-14y. In absolute terms, the highest risk of BCa per 10,000 survivors each year was in survivors: of NHL (AER - 1.6) and retinoblastoma (1.5), originally diagnosed 10-14y (0.6), males (0.6), and those with the longest follow-up i.e. >35y (2.0).

Descriptive: To the end of year 2005, 2 further cases were observed. Latency between 1st and 2nd cancer was 156-588 months, median 386 months. Of the 21 cases, 14 were transitional cell carcinomas, 4 leiomyosarcomas, 2 adenocarcinomas and 1 rhabdomyosarcoma. Nine cases were exp;osed to CPM alone; 2 to CPM and abdominal radiotherapy (RT); 3 to RT alone; 6 received neither; and for 1, treatment was unknown. Nine patients had history of smoking. 2 cases had a family history of BCa. No occupational risk for BCa was noted in any case.

Conclusions:

This large population-based cohort study shows that although the risk of BCa within 5y survivors of childhood cancer was low, survivors were 5 times more likely to develop BCa than the general population. Survivors originally diagnosed at 0-4y, and those diagnosed with retinoblastoma, leukemia and NHL, were all at a particular higher risk. We plan to establish a case-control study to better investigate the effects of treatment on the etiology of second-malignant BCa following childhood cancer.

Presented by Pratik M Gurung, MD, Clare Frobisher, MD, Alison Leiper, MD, Christopher R J Woodhouse, MD, and Michael M Hawkins, MD, at the Annual Meeting of the American Urological Association (AUA) - May 17 - 22, 2008. Orange County Convention Center - Orlando, Florida, USA.

Reported by UroToday Contributing Editor Christopher P. Evans, MD, FACS

UroToday - the only urology website with original content global urology key opinion leaders actively engaged in clinical practice.

To access the latest urology news releases from UroToday, go to: www.urotoday

Copyright © 2008 - UroToday