Meningioma as the host for metastatic breast cancer: A rare occurrence with important therapeutic impact

BACKGROUND: Tumor-to-tumor metastasis is a rare condition. There are few reports of metastatic tumors within intracranial tumors, including meningiomas. Since some metastatic tumors have osteoblastic imaging pattern, it is not always easy to differentiate them from meningioma on preoperative studies. CASE DESCRIPTION: A 60-year-old female referred to our center complaining about a progressive headache, nausea, and vomiting for the past month. She had a history of breast cancer treated with radical mastectomy (5 years ago) and adjuvant chemotherapy (until 1 year ago). Workups revealed a dural-based mass in the left temporobasal and midline subfrontal regions. Histopathological study showed breast cancer metastasis nests within the primary meningioma. CONCLUSION: As the diagnosis of metastatic nests inside a benign tumor, drastically alters postoperative adjuvant treatments, a high index of suspicion is needed evaluating tumors from patients with a history of systemic neoplasms.