Small cell carcinoma of the lung metastatic to the wall of a radicular cyst.

This case report details the unusual presentation of small cell carcinoma at the periapex of a maxillary left lateral incisor. The initial clinical presentation was that of a symptomatic, nonhealing, well-circumscribed radiolucency about the periapex of the tooth. The biopsy specimen submitted by the endodontist was diagnosed as small cell carcinoma. This report stresses the need for submission of all tissue removed from the oral cavity for histopathological examination.