Peri-Implant Metastasis as First Manifestation of an Unknown Lung Cancer: Literature Review and Two New Cases

Metastases around dental implants are extremely rare. They usually represent a secondary localization of a multiorgan metastatic neoplasm but also are, exceptionally, recognized as the first clinical manifestation of a still unknown cancer of whatever organ. Metastases usually manifest as rapidly growing lesions of hard and soft tissues and always represent a true diagnostic/therapeutic dilemma both for clinicians in choosing the more appropriate treatment and for pathologists in recognizing the primary tumor when still undiagnosed. We report 2 distinct cases of metastasis occurring around dental implants in the maxilla and mimicking peri-implantitis at the onset; more precisely, in one case, the lesion involved exclusively the alveolar bone, where an implant were previously inserted, while in the other case, a neoplasm caused bone destruction around the fixture with an impressive and rapid exophytic growth. In both cases, maxillary lesions were the first metastatic manifestation of an unknown adenocarcinoma of the lung.