Triple Negative Invasive Ductal Carcinoma of Breast with Oral Metastasis: A Case Report

Metastatic oral malignancies have been reported in the mandible, tongue, and gingiva. Breast cancer oral metastasis usually presents as a benign oral lesion clinically. At histology, it shares several features with metastatic carcinoma. Immunohistochemistry (IHC) can be useful in the differential diagnosis. The clinical presentation consisted of swelling in the upper front tooth region in a 35-year-old woman. The lesion was excised under local anaesthesia and underwent histological and immunohistochemical examination to rule out any malignancy. Histological findings, Pan CK positivity suggesting the epithelial origin and the absence of reactivity to Oestrogen Receptor (ER), Progesterone Receptor (PR), Human Epidermal Growth Factor Receptor-2 (HER2) indicated metastatic triple negative breast carcinoma. The histological diagnosis of metastatic breast carcinoma can be confirmed by IHC. The current case report illustrates the necessity of including a panel of IHC markers in confirming the diagnosis of metastatic lesions in oral cavity. By utilising such panels, one can expedite the prognosis and prevent delay in diagnosis.