Irradiation toxic effects during intra-arterial chemotherapy for retinoblastoma: should we be concerned?

OBJECTIVE To evaluate irradiation toxic effects from fluoroscopy during intra-arterial chemotherapy for retinoblastoma. DESIGN Prospective trial. PARTICIPANTS Eight patients treated with intra-arterial chemotherapy. MAIN OUTCOME MEASURES Irradiation toxic effects in vital organs. RESULTS The mean patient age was 29 months (range, 10-74 months) and 63% were male. The mean irradiation dose to the skin of the affected eye was 0.19173 Gy, to the contralateral eye was 0.03533 Gy, to the chest wall was 0.00296 Gy, and to the abdominal wall was 0.00104 Gy. The estimated irradiation dose to the lens in the treatment eye was 0.16 Gy, which, in accumulated doses, could be cataractogenic. The estimated irradiation dose from a single fluoroscopy session to other organs, including the brain (0.05560 Gy), thyroid (0.00192 Gy), bone marrow (0.00059 Gy), and gonads (0.00015 Gy), was far lower than the minimal toxic level. CONCLUSIONS Careful use of fluoroscopy during intra-arterial chemotherapy with limited irradiation exposure is advised. Accumulated irradiation toxic effects following multiple sessions of intra-arterial chemotherapy could be cataractogenic and possibly carcinogenic, especially in irradiation-sensitive patients with retinoblastoma.