Safety and efficacy of splenic irradiation in the treatment of patients with idiopathic myelofibrosis: a report on 15 patients.

Splenic irradiation in idiopathic myelofibrosis (IMF) has often been use d in selected situations when other therapies were unefficient or contraindicated. This could improve quality of life of patients, but literature remains rare in this field. We have assessed the impact of splenic irradiation in 15 patients with IMF. All of them were no longer responsive to usual treatments, and they presented at least one of the following features: constitutional symptoms, splenic pain, large splenic size, and anemia requiring >2 units of red blood cell transfusion per month. The planned schedule of radiotherapy consisted in daily fractions of 0.4-1 Gy. The median dose of radiotherapy per treatment was 9.8 Gy (range, 0.6-30.5). The overall response rate was 59% with a median duration of 10 months (range, 1-19). Splenic irradiation was more effective on constitutional symptoms, splenic pain, and spleen size. The best responses were noted when full doses of radiotherapy could be delivered, and when patients were previously fewly transfused. Splenic irradiation effectively palliates IMF-related symptoms, and constitute an alternative therapy for patients refractory to usual treatments.