Low-Dose Splenic Irradiation is Effective for Patients With Hematological Diseases Who Have Symptomatic Splenomegaly

Abstract

Splenic irradiation was commonly used for symptomatic relief in patients with hematologic disease. In this study, we assessed the response rate and the improvement of hemogram in patients with extramedullary hematopoiesis who received splenic irradiation. We also investigated the adverse effect of splenic irradiation in the same group of tumors. Between June 2004 and July 2016, 23 patients with hematological diseases who received splenic irradiation for symptomatic splenomegaly were included in this study. All patients were treated with splenic irradiation using two anterior-posterior field configurations (3D conformal radiotherapy technique or forward “field in field” intensity modulated radiotherapy technique). The symptom relief and hematological adverse effects were assessed. A total of 23 patients with symptomatic splenomegaly, including 19 cases of myelofibrosis, 3 cases of acute myeloid leukemia, and one with mantle cell lymphoma were analyzed. The radiation prescription dose ranged from 1 Gy to 5 Gy, with a median dose of 4 Gy, in 0.5 to 1 Gy per fraction (twice a week). Splenic irradiation resulted in splenomegaly regression with symptom relief in 21 (91.3%) of 23 cases. Among 21 cases, 3 cases had significant reduction of splenic size 1 week after completing radiotherapy. Grade 3 myelosuppression was observed in four patients, and that the hemogram of these patients improved subsequently after component therapy. Our results indicated that low-dose splenic irradiation with a median of 4 Gy provides an effective and well-tolerated palliative treatment option for symptomatic splenomegaly in patients with hematologic disease.