Jaw Metastasis from a Prostate Adenocarcinoma Associated with Numb Chin Syndrome: Case Report

Abstract

AbstractNumb chin syndrome is an uncommon maxillofacial manifestation involving mental neuropathic complications of mandibular bone metastasis with prostate adenocarcinoma. We report a case of a male, 68 years, with a history of bone tibia and spinal metastatic prostate cancer, undergoing bilateral orchiectomy for hormonal blockade and chemotherapy; disease progression was confirmed by bone scintigraphy which noted no critical points but an increase in alkaline phosphatase; therapy with abiraterone and zoledronic acid quarterly was introduced 1 year after diagnosis. The patient attended a dental appointment after 10 months of bisphosphonate use, complaining of a “tingling” sensation in the right chin mental region, 6 months after tooth extraction, with diagnostic hypothesis of medication-related jaw osteonecrosis. Intra-oral exam showed edema in the right mandibular body region extending to the painless, hardened chin, with exudate drainage as compression. An incisional biopsy was performed and anatomopathological and immunohistochemical analysis showed positive staining for cytokines and NKX3, confirming the diagnosis of adenocarcinoma metastasis. The patient was referred to continue treatment with radiotherapy and, subsequently, Xofigo and zoledronic acid to improve symptomatology and control of the adenocarcinoma. Facial numbness should alert clinicians to the potential of metastatic disease in any patient who presents with chin or jaw numbness and has no other obvious cause for their complaint, and early differential diagnosis between jaw osteonecrosis and bone metastasis in the jaw is important for immediate management and improvement in treatment and quality of life.