Scattered radiation to gonads: Role of testicular shielding for para-aortic and homolateral illiac nodal radiotherapy

Abstract

BackgroundScattered radiation to organs at risk deserves great attention during radiotherapy especially when the concern is about fertility. Minimizing the delivery of scattered radiation to the gonads while treating abdominal nodes or pelvic fields in male patients requires adequate shielding of the testes to preserve testicular functions. We constructed a testicular shield with cerrobend for the purpose of treatment of seminoma of testis stage I and IIA disease. Materials & methodsAn outer shell of coconut of required dimensions was taken as a base over which cerrobend was poured to obtain two semi-spherical half testicular shields. Five patients of seminoma early stage (stage I and IIA) were treated with this testicular shield. ResultsThe estimated total dose received by the testis by scatter radiation after completion of the treatment was 0.115Gy (0.28%) of total mid-plane dose of 40Gy delivered by inverted Y field. At a distance of 8cm from the inferior field border the 2cm thick cerrobend testicular shield provided a shielding factor of 3.2/0.3=10.33. ConclusionsWith proper testicular shielding, doses as low as 0.28% of the prescribed dose can be achieved. This low dose is believed to maintain the fertility of the patient.