Over 20 Years of Progress in Radiation Oncology: Seminoma.
During the past 20 years, significant changes have occurred in the management of seminoma. Survival has improved by approximately 10%, and now 97% of patients are cured. Reductions in the numbers of patients irradiated, the volumes irradiated, and the doses used should reduce morbidity. The 1973 Patterns of Care Study (PCS) and the planned new study proffer statements of consensus on optimal care and evaluate compliance with guidelines. Specific changes in investigation, including measurement of the serum tumor markers beta human choriaonic gonadotropin (betaHCG) and alphafetoprotein (AFP) and computed tomography (CT) or magnetic resonance imaging (MRI) evaluation of the retroperitoneum, better evaluate disease extent. For stage I disease, a reduction in the total dose of infradiaphragmatic irradiation to 2,500 cGy is recommended. An option for surveillance reduces unnecessary therapy in 80% and may improve fertility. The significance of disease bulk in stage II has been recognized, and treatment has been refined. The maximal radiation dose now recommended for stage II disease is 3,500 cGy. CT definition of radiation target volumes minimizes the risk of geographic miss. Prophylactic mediastinal irradiation is no longer recommended. Chemotherapy, usually now bleomycin, etoposide, and cisplatin, produces high cure rates for stage IID, III< and IV disease and has become the standard managemetn. Controversy still surrounds optimal therapy for stage IIC disease. Unresolved questions include cost benefit and quality of life issues surrounding optimal management for stage I disease, inguinal scrotal irradiation in stage I and II disease, and identification of the least toxic but effective chemotherapy for specific subgroups of patients with advanced disease.
Thomas
GM
Department of Radiation Oncology, University of Toronto, Toronto, Canada