Chemotherapeutic induction of radiation recall (RR) is a rare event in which a chemotherapeutic agent given days to years after radiation therapy causes an inflammation reaction of the tissues within the irradiated area—“recalling” increased radiation effects to that area. In this unique case, a 14-year-old girl with a synovial sarcoma of the forearm was treated with neoadjuvant chemotherapy and radiation therapy. Gemcitabine was administered in an adjuvant setting inducing a RR reaction. The severity of the inflammation resulted in a forearm myositis secondarily causing a compartment syndrome that was treated with several prolonged courses of corticosteroids. The symptoms of RR and compartment syndrome have resolved 1 year postonset, although magnetic resonance imaging continues to show myositis and soft-tissue edema. This case highlights the need to maintain a heightened awareness to recognizing the signs and symptoms of RR and the potential severity of RR in pediatric cancer patients in conjunction with chemotherapeutic agents used more frequently in adults.