Metastatic colonic adenocarcinoma presenting in the oral cavity: Disease progression over time.

A 55-year-old female patient with a history of colonic adenocarcinoma and metastases to the liver, retroperitoneum, lungs, and 11th rib (T3N1M1, clinical stage IVc) was referred for evaluation of a painful lesion in the retromolar trigone. Surgical intervention, chemotherapy, and radiotherapy were mentioned in the medical history for the intestinal condition. Extraoral examination revealed a hardened enlargement on the left hemiface. Intraoral examination showed a vegetative, ulcerative, infiltrative, and bleeding lesion in the left retromolar trigone. Computed tomography demonstrated an expansive lesion with a lytic component and cortical discontinuity in the left ascending mandibular ramus. An incisional biopsy revealed a proliferative epithelial component characterized by irregular tubular structures lined by columnar cells with variable pleomorphism. The tumor cells proved negative for CK7 and positive for CK20, which, combined with diffuse positivity for CDX2, confirmed that the cancer originated primarily in the intestinal epithelium. The Ki-67 index was 90 %. These findings confirmed the diagnosis of metastatic colonic adenocarcinoma to the oral cavity. At the time of the diagnosis of the oral metastasis, 52 months after the initial diagnosis, the patient was already receiving palliative treatment.