Metastatic Lesions to the Oral Soft Tissues and Bones: A Seventeen-Year Retrospective Study

Abstract

<h3>Introduction</h3> Metastatic neoplasms to the oral soft tissues and bones are exceedingly rare and are associated with poor prognosis. Clinically, metastatic lesions exhibit a strong predilection to the jaw bones, specifically the posterior mandible, while soft tissue involvement includes the gingiva and tongue. Metastatic tumors may pose diagnostic challenges since their histopathologic appearance varies. Herein, we report the clinico-epidemiologic and histopathologic characteristics of forty-one metastatic lesions to the oral mucosa and jaws. <h3>Material and methods</h3> Cases diagnosed as metastatic lesions during the period 2003-2020 were retrieved. The demographic features (age and gender of the patients), clinical impression and location, as well as primary site and histologic type of the neoplasms were recorded. <h3>Results</h3> Among 126,229 biopsy specimens, only 41 (0.03%) comprised metastases. The patients' mean age was 67.6 years (age range=18-94 years) without any apparent gender bias (male: female ratio=21:20). The possibility of metastasis was considered in only half (21, 51%) of the cases. Twenty-two cases affected the gingiva (54%); six (27.3%) presented with tautochronous bone involvement. Ten cases (24%) were exclusively intraosseous and manifested as ill-defined, unilocular, mandibular radiolucencies. Other anatomic sites included the alveolar mucosa and hard palate (3 each, 7.3%), tongue (2, 5%) and soft palate (1, 2.4%). Collectively, the most common primary site was the lung (12, 29%) followed by the colon (6, 15%), breast and kidney (4 each, 10%), pancreas (2, 5%), and prostate, heart, esophagus, sublingual gland, adrenal, bone and CNS (1 each, 2.4%). In six cases (15%) the primary was unknown. In both men and women, lung was the most common primary site (33.3% and 25%, respectively). <h3>Conclusions</h3> Metastases to the oral cavity and jaws are rare. When present, they show a predilection for the gingiva and mandible. Clinicians should remain aware about metastatic neoplasms since they can frequently mimic reactive pathoses.