Regorafenib-Induced Hand-Foot Skin Reaction in an Adolescent.

Regorafenib is a multikinase inhibitor commonly used in the management of hepatocellular carcinoma, gastrointestinal stromal tumors (GIST), and colorectal cancer. It is also used off-label for progressive or metastatic osteosarcoma, which is the most common primary bone malignancy in children and adolescents. While hand-foot skin reaction (HFSR) is a well-documented side effect associated with regorafenib use, no standard guidelines currently exist for preventing and managing regorafenib-associated HFSR in children, or for HFSR and hand-foot syndrome related to other chemotherapy agents. We present a case of regorafenib-induced HFSR in an adolescent with metastatic osteosarcoma that highlights an effective dose-reduction regimen and treatment plan that ultimately resolved her grade 3 HFSR and allowed her to resume alternate anticancer treatment immediately.