Late Effects of Craniospinal Irradiation Using Electron Spinal Fields for Pediatric Patients With Cancer

Purpose: For children, craniospinal irradiation (CSI) with photons is associated with significant toxic effects. The use of elec-trons for spinal fields is hypothesized to spare anterior structures but the long-term effects remain uncertain. We studied late effects of CSI using electrons for spinal radiation therapy (RT).Methods and Materials: Records of 84 consecutive patients treated with CSI using electrons for the spine at a single institu-tion between 1983 and 2014 were reviewed. Median age at RT was 5 (range, 1-14) years. The most common histologies were medulloblastoma/primitive neuroectodermal tumor (59%) and ependymoma (8%). The median prescribed dose to the entire spine was 30 Gy (range, 6-45). A subset of 48 (57%) patients aged 2 to 14 at RT with clinical follow-up for & GE;5 years was ana-lyzed for late effects. Height z scores adjusted for age before and after CSI were assessed using stature-for-age charts and com-pared with a t test.Results: At median follow-up of 19 years (range, 0-38 years), the median survival was 22 years (95% confidence interval, 12-28 years) after RT, with 47 patients (56%) alive at last follow-up. On subset analysis for late effects, 19 (40%) patients developed hypothyroidism and 5 (10%) developed secondary malignancies. Other complications reported were esophageal stricture and periaortic hemorrhage in 1 and restrictive pulmonary disease in 1 patient. Median height z score before treatment was -0.4 (36th percentile; interquartile range, -1.0 to 0.0) and at last follow-up was -2.2 (first percentile; interquartile range, -3.1 to -1.6; P < .001). Of 44 patients with spinal curvature assessments, 15 (34%) had scoliosis with median Cobb angle 15 & DEG; (range, 10 & DEG;-35 & DEG;) and 1 (2%) required surgery.Conclusions: Frequent musculoskeletal toxic effects and predominantly decreased height were seen with long-term follow-up. Scoliosis and hypothyroidism were each seen in at least one-third of long-term survivors. However, clinically evident esoph-ageal, pulmonary , cardiac toxic effects were infrequent. & COPY; 2022 Elsevier Inc. All rights reserved.

Automated summary

This study reviewed the records of 84 patients who received spinal radiation therapy using electrons between 1983 and 2014. The results showed that long-term follow-up revealed musculoskeletal toxic effects and decreased height, while pulmonary and cardiac toxic effects were rare.