Affiliation:
1. Extracranial Solid Tumors Unit Pediatric Cancer Center Barcelona Barcelona Spain
2. Radiation Oncology Unit Vall d'Hebron Hospital Barcelona Spain
3. Fundació Sant Joan de Déu per a la Recerca Barcelona Spain
4. Oncology Pharmacy Unit Pediatric Cancer Center Barcelona Barcelona Spain
Abstract
AbstractIntroductionRadiation recall reaction (RRR) is a rare inflammatory reaction developing in a previously irradiated field after a triggering agent. In pediatric patients, it is poorly understood and deficiently studied. Gemcitabine–docetaxel (G/D) in childhood cancer is mainly used as a salvage regimen for sarcomas. We aim to describe RRR triggered by G/D in children.Patients and methodsRetrospective review of 21 patients receiving G/D along with radiotherapy at two hospitals from 2010 until 2022. RRR was considered as any toxicity occurring after G/D administration in a previously irradiated field. RRR features were described. Fisher's and Mann–Whitney tests were utilized to analyze the risk factors involved.ResultsSixteen episodes of RRR developed in 16 (76.2%) patients. RRR mainly involved deep layers of the skin (58%) and occurred predominantly after two G/D cycles. The mean time between radiotherapy and chemotherapy was 28.5 days (0–1359 days), and the mean radiation volume 391 mL (157–1810 mL) for RRR. RRR treatment was mainly systemic steroids, with partial responses in six of 11 (58%) patients. Re‐exposure to G/D was associated with a high rate of recurrence in nine of 15 (56.2%), prompting drug discontinuation. The major risk factors for RRR after G/D include, without statistical significance, a larger volume of the irradiated field and a shorter interval between chemotherapy and radiotherapy.ConclusionsThe incidence of RRR after G/D in the pediatric population is higher than previously reported. Drug re‐exposure is usually followed by recurrence. Higher irradiated volumes and a shorter time to the start of chemotherapy could be related with an increased risk of RRR.