title: Severe hypercalcemia following denosumab treatment in a juvenile patient.
abstract: A 10-year-old boy diagnosed with unresectable giant cell tumor of bone in the sacrum was treated with a bone modifying agent denosumab. Administration of denosumab showed excellent clinical response without any major complications, and the tumor was surgically removed afterwards. However, 4 months after discontinuing denosumab, the patient developed severe hypercalcemia (15.2 mg/dl). There was a sharp surge in the levels of bone resorption markers, indicating that disregulated overt bone resorption after the discontinuation of denosumab led to hypercalcemia. The patient was treated with bisphosphonate and barely recovered from the life-threatening conditions. This case shows that a robust rebound of bone resorption may occur following cessation of denosumab and suggests that hypercalcemia is an underappreciated side effect of denosumab therapy in children.
authors.affiliation: Division of Musculoskeletal Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Nokitaka
authors.initials: N
authors.lastname: Setsu
authors.affiliation: Division of Musculoskeletal Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan. ekobayas@ncc.go.jp.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Kobayashi
authors.affiliation: Division of Musculoskeletal Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Asano
authors.affiliation: Division of Pediatric Oncology, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Yasui
authors.affiliation: Division of Pediatric Oncology, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawamoto
authors.affiliation: Division of Musculoskeletal Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kawai
authors.affiliation: Department of Orthopedic Surgery, Keio University, School of Medicine, Tokyo, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Horiuchi
mesh_terms: D050071:Bone Density Conservation Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001859:Bone Neoplasms / Q000188:drug therapy; D001862:Bone Resorption / Q000139:chemically induced; D002648:Child; D000069448:Denosumab / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D006934:Hypercalcemia / Q000139:chemically induced*; D008297:Male
chemical_list: D050071:Bone Density Conservation Agents; D000069448:Denosumab
keywords: Denosumab; Giant cell tumor of bone; Hypercalcemia; Pediatric