Background: Children with paratesticular rhabdomyosarcoma (RMS) have both a good prognosis and a high survival rate. The clinical behaviour and outcome of the disease in adults is not well described.
Patients and methods: We reviewed retrospectively our experience with paratesticular RMS in patients older than 16 years during a 16-year period (1975-1991).
Results: Thirteen adult patients with paratesticular RMS are reported. Median age was 21 years (range 16 to 31). Presentation characteristics were scrotal mass in 11 cases, lumbar pain and weight loss in 5 cases, hypercalcemia in 3 cases and thrombocytopenia in 3 cases. There were 5 patients with stage IV, 2 with stage IIB and 6 with stage IA (IRS classification). The 5 stage IV patients are reported in detail, with initial bone marrow infiltration encountered in 4 of them. Objective response to chemotherapy was achieved in all 6 patients with measurable disease (2 CR + 4 PR). Two of 7 patients who received adjuvant chemotherapy relapsed at 7 and 11 months. After a median follow-up of 90 months, 8 patients (5 stage IV, 3 stage IA) died from disease progression.
Conclusion: Metastatic disease with bone marrow involvement at presentation and aggressive behaviour seem to be more relevant in adult paratesticular RMS patients compared with children.