Short-time splenic irradiation for splenomegaly

Abstract

Background: Splenic irradiation is routinely used in the supportive treatment of lymphoepithelial and hemopoietic diseases associated with splenomegaly. A new short-time irradiation schedule with conventional dosage (Group A: 2 Gy/fract.) was compared retrospectively with low-dose prolonged treatment schedules (Group B: < or = 1 Gy/fract.) to establish its tolerance and its efficacy in terms of relieving splenomegaly-associated symptoms.

Patients and method: Between 12/1996 and 3/2002 49 patients (6 with CLL, 14 with CML, 6 with NHL, 16 with MPD, 6 with OMF and 1 with AML) underwent 85 treatment courses (13 courses low-dose prolonged treatment and 72 courses short-time treatment).The spleens had been exposed to pretreatment doses of 3-70 Gy (mean 20.75 Gy). Splenic size was 12-35 cm (mean 22.76 cm). One treatment was done with 60Co. 9-20 MeV electron beams were used in 23 treatments and 6 MV photons in 61 treatments. Blood counts were monitored daily. Clinical improvement (pain relief, improvement of splenomegaly-associated symptoms), spleen volume reduction and effects on blood counts were evaluated and documented at the end of the treatment.

Results: Of the 85 treated patients, 55 (Group A: 47/72, Group B: 8/13) showed a > 10% reduction of spleen volume and 62 (Group A: 57/72, Group B: 5/13) clinical improvement. 15 of 49 patients underwent multiple irradiation (2-8 courses) without clinical or hematologic complications. The intervals between the courses were 2-19 months. Rapid response in terms of reduction in splenic size in 23 patients permitted field reduction during treatment. Significant hematologic abnormalities were absent throughout.

Conclusion: The short-time treatment schedule ensured a rapid response with relief of pain and improvement of gastrointestinal and pulmonary symptoms at an overall treatment time shorter than that of low-dose prolonged treatment schedules. No differences in terms of hematologic abnormalities were found between single doses of 2 Gy and < or = 1 Gy.