Long-term complications of total body irradiation in adults

To report long-term pulmonary, thyroid, and ocular complications in patients who had conditioning regimens including total body irradiation (TBI) before bone marrow transplantation (BMT).

Between June 1986 and December 1995, 478 patients received TBI in our institution. The present study includes 186 adult patients who had complete remission lasting one year or more after BMT. There were 108 males and 78 females. Median age was 36.5 years (range 15-60). Initial diagnoses were lymphomas (50%), acute lymphoid leukemias (16%), acute myeloid leukemias (16%), chronic myeloid leukemia (13%), aplastic anemia (3%), and myelodysplasia (2%). At the time of BMT, 43.5% of patients were in complete response and 56.5% in partial response. Treatment consisted of a single dose TBI at 10 Gy in 9% and fractionated TBI delivering 12 to 13.5 Gy in 6 fractions in 91%. From 1986 to October 1991, TBI was performed in lateral position with 9 MV energy (57% of patients) and thereafter in alternate prone and supine positions with 15 MV energy (43%). Chemical conditioning regimen was cyclophosphamide (60 mg/kg at D-4 and D-3) in 69% and CBV (cyclophosphamide 1500 mg/m(2) from D-6 to D-3, BCNU 300 mg/m(2) at D-6, VP-16 200 mg/m(2) from D-6 to D-4) in 25%. Fifty eight percent of patients received autologous and 42% allogeneic BMT. All patients had clinical, biologic, and functional examinations at one-year intervals.

Median follow-up from BMT was 49 months (range 12-136). Late pulmonary effects were observed only in functional explorations, without clinical effect, including restrictive syndrome in 8% and alteration in the diffusing capacity of carbon monoxide in 12%. No patient showed clinical thyroid symptoms, and 10% developed biologic dysfunction: hypothyroidism (6.5%), thyroiditis (3%), and Basedow disease (0.5%). Ocular complications occurred in 29.5%, including cataract (15%), dry syndrome (13%), and keratitis (1.5%). In univariate and multivariate analysis, pulmonary complications were statistically increased by chronicle graft vs. host disease (GVHD) vs. no (p = 0.02), prone and supine vs. lateral TBI position (p = 0.02), and with 15 MV vs. 9 MV beam energy (p = 0.02). Cataract occurred less frequently with fractionated than with single-dose TBI (p = 0.000002). No differences were observed regarding age, sex, initial diagnosis, status at the time of BMT, conditioning chemotherapy regimen, and total dose of TBI.

From this retrospective study it was shown that long-term complications of TBI were not symptomatic in most patients. The role of parameters of irradiation and especially position of treatment and beam energy should be emphasized and assessed with a longer follow-up.