Häfliger Simon, Seidel Ann-Katrin, Schoch Eric, Reichmann Jan, Wild Damian, Steinmann-Schwager Stephanie, Pless Miklos
Department of Medical Oncology, Kantonsspital Winterthur, Winterthur, Switzerland.
Department of Radiology, Kantonsspital Winterthur, Winterthur, Switzerland.
Case Rep Oncol. 2020 Nov 30;13(3):1373-1380. doi: 10.1159/000510334. eCollection 2020 Sep-Dec.
Tumor-induced osteomalacia is a very rare paraneoplastic syndrome. It can be caused by phosphaturic mesenchymal tumor (PMT), a generally benign tumor that produces fibroblast growth factor 23 (FGF-23), which can cause a severe renal phosphate wasting syndrome. Upon complete surgical removal of the tumor, FGF-23 normalizes and the osteomalacia is cured. In cases in which surgery is not feasible, radiofrequency ablation (RFA) is the treatment of choice. We describe a case with a PMT situated in the sacrum, in close proximity to the sacral plexus. Both surgery and RFA were considered potentially nerve damaging. Since the tumor showed expression of somatostatin receptors, we opted for a peptide receptor radionuclide therapy (PRRT) with Lu-DOTATOC. However, the therapy did not show the expected success, since the FGF-23 level had even temporarily increased. The patient was then successfully treated with RFA. A partial remission of the tumor was achieved and FGF-23 levels nearly normalized. Despite some severe neurological side effects, the patient showed a remarkable clinical improvement, with no symptoms of osteomalacia within a few weeks.
肿瘤诱导的骨软化症是一种非常罕见的副肿瘤综合征。它可由排磷性间叶肿瘤（PMT）引起，PMT是一种通常为良性的肿瘤，可产生成纤维细胞生长因子23（FGF-23），进而可导致严重的肾脏磷酸盐消耗综合征。肿瘤完全手术切除后，FGF-23恢复正常，骨软化症得以治愈。在无法进行手术的情况下，射频消融（RFA）是首选治疗方法。我们描述了一例PMT位于骶骨且紧邻骶丛的病例。手术和RFA均被认为可能会损伤神经。由于肿瘤显示生长抑素受体表达，我们选择用177Lu-DOTATOC进行肽受体放射性核素治疗（PRRT）。然而，该治疗未取得预期效果，因为FGF-23水平甚至出现了暂时升高。随后患者接受RFA治疗成功。肿瘤部分缓解，FGF-23水平几乎恢复正常。尽管出现了一些严重的神经副作用，但患者临床症状显著改善，几周内骨软化症症状消失。
