Evaluation of fractionated total body irradiation and dose rate on cataractogenesis in bone marrow transplantation.
OBJECTIVE
To assess dose rate effect on cataractogenesis in allogeneic or autologous bone marrow transplanted patients conditioned with fractionated total-body irradiation (FTBI).


METHODS
Between 1987 and 2001, a total of 105 patients have received TBI conditioning for Bone Marrow Transplantation (BMT) for hematological malignancies at Gulhane Military Medical School. 12 Gy FTBI was applied in 6 fractions over 3 consecutive days with a Co60 teletherapy machine. 46 patients who have survived and were followed up after more than one year were evaluated for cataractogenesis in relation to dose rate. Conditioning therapy included only cyclophosphamide (60 mg/kg/day for two days) + TBI with no steroid and veno-occlusive disease prophylaxis.


RESULTS
The median follow-up is 32 months. Posterior subcapsular cataract developed in 5 eyes of three patients out of 46 patients. The 5-year and 10-year estimated cataract incidence in the high-dose rate (> 0.04 Gy/min) group was 29% and 43% respectively while no cataracts occurred in the low-dose rate (< or = 0.04 Gy/min) group. Cataract development in the high-dose rate group versus low-dose rate group was statistically significant (p < 0.039).


CONCLUSIONS
Cataract is a late side effect of TBI. Low-dose rate fractionated TBI is a reliable conditioning program in BMT with effective lens sparing to avoid cataractogenesis.
Beyzadeoglu
Murat
M
Department of Radiation Oncology, Gulhane Military Medical School, Ankara, Turkey. mbeyzadeoglu@gata.edu.tr
Dirican
Bahar
B
Oysul
Kaan
K
Arpaci
Fikret
F
Pak
Yucel
Y
D000293:Adolescent; D000328:Adult; D016026:Bone Marrow Transplantation / Q000009:adverse effects / Q000379:methods*; D002386:Cataract / Q000209:etiology*; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D019337:Hematologic Neoplasms / Q000150:complications / Q000628:therapy; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D019172:Transplantation Conditioning / Q000379:methods; D014916:Whole-Body Irradiation / Q000009:adverse effects*