Association Between Temporomandibular Joint Disorders and Metastatic Breast Cancer—A Mapping Review

Aim: The authors of the present study speculate that metastasis of breast cancer cells to the temporomandibular joint (TMJ) region mimics classical signs and symptoms of temporomandibular disorders (TMD). The aim of this mapping review was to investigate the association between metastatic breast cancer (MBC) and TMD. Materials and Methods: The focused question was, “Is there an association between MBC and TMD?” Indexed databases (PubMed/Medline, EMBASE, OVID, Scopus, Google Scholar, and Web of Science) were electronically searched up to and including March 2022. These databases were searched using different combinations of the following keywords: cancer, carcinoma, temporomandibular disorders, temporomandibular joint, disc displacement disorder, nociception, and tumor. Original clinical studies that meet the inclusion criteria were included. The risk of bias (RoB) was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for case reports. The structure of this current evidence-based review was tailored to primarily condense the relevant information. Results: Fifteen case reports were selected after screening the retrieved records from the electronic search. Fifteen out of 16 patients were women aged between 32 and 78 years. All patients were diagnosed with MBC, and most presented with adenocarcinoma. The symptoms identified in patients with TMD included: (a) preauricular pain; (b) preauricular swelling; (c) limited mouth opening; and (d) malocclusion. Fourteen of the included studies had a low RoB, while one had a moderate RoB. Conclusion: Based on the currently available evidence, a direct association between TMD and MBC or vice versa cannot be established. Routine visits to medical and oro-dental healthcare providers can contribute toward early diagnosis and management of TMD and MBC.