Metastatic colon cancers to the oral cavity are unusual, involving a majority of the mandible rather than the oral soft tissues. We describe a rare site of gingival metastasis in a case of rectosigmoid cancer. The patient was a 74-year-old woman who developed swelling and persistent bleeding of the right mandibular gingiva after tooth extraction. A PET/CT using 18F-FDG depicted multiple metastatic lesions in the neck, lung, abdominal wall, and mandibular gingiva. Histologic study of the gingival lesion confirmed the diagnosis of gingival metastasis from colon adenocarcinoma.
From the *Departments of Nuclear Medicine, Taipei Veterans General Hospital; †National Yang-Ming University School of Medicine; and ‡Department of Pathology, Taipei Veterans General Hospital, Taipei, Taiwan.
Received for publication November 6, 2012; revision accepted October 2, 2013.
Conflicts of interest and sources of funding: none declared.
Reprints: Rong-Hsin Yang, MD, Department of Nuclear Medicine, Taipei Veterans General Hospital, No. 201, Sec. 2, Shipai Rd, Beitou District, Taipei City, Taiwan 11217, Republic of China. E-mail: email@example.com.