A Case Report on Mandibular Metastasis From a Breast Carcinoma

Despite the rise in the number of cases of breast cancer in recent years, clinical diagnosis of a primary tumor in cases presenting with metastasis to the oral cavity poses a challenge in modern medicine because of its rare presentation. We report a case of breast cancer which presented as a painless swelling in the jaw. A 37-year-old multiparous woman consulted her dentist with complaints of toothache and swelling over the right cheek. On examination, she was diagnosed with dental caries and an orthopantomogram (OPG) was done to evaluate the swelling which revealed an area of rarefaction with an irregular margin on the right angle of the mandible. With suspicion of malignancy, the head, neck, oral and pharyngeal regions were thoroughly inspected and palpated. An ultrasonogram (USG) of the neck was done, which was normal and a core needle biopsy of the oral swelling was performed which showed metastatic carcinomatous deposits with pan-cytokeratin (PAN-CK) positivity, estrogen receptor (ER) positivity, and the Ki-67 value was 10% to 20% which was suggestive of breast carcinoma metastasis. Thereafter, the patient was referred for a surgeon's opinion. A breast examination was then done which revealed a lump in the right breast with a retracted nipple. A core needle biopsy of the lump revealed that it was ER and progesterone receptor (PR) positive and human epidermal growth factor receptor 2 (HER-2/neu) negative which confirmed the clinical diagnosis of breast cancer. Since the incidence of oral metastatic tumors is low, the likelihood of an early diagnosis of the distant primary tumor is reduced. Hence, all lesions of the oral cavity should be evaluated with due diligence considering the possibility of it being secondary metastases from distant tumors.