A clinicopathologic study of surgically resected metastatic lesions of brain: A single institutional experience

Introduction: One of the most common tumors of the brain are metastatic lesions. They can present as cancer of unknown primary (CUP) and require careful determination of the site of origin of the primary. Histopathologic and immunohistochemical analysis helps to determine the primary site. Aim: To study the clinicopathological features of metastatic tumors of the brain. Materials and Methods: All cases of surgically resected brain metastasis (solid tumor metastasis) from January 2013 to April 2015 were included in the study. The clinical details including age, gender, clinical features, and location were taken from medical records. The histopathology slides were retrieved and reviewed along with clinical and imaging findings from medical records. Immunohistochemistry was performed wherever necessary. Results: Out of 1662 resected brain lesions during the study period, 69 accounted for central nervous system metastasis, of which 36 were brain metastasis and 33 were isolated spinal cord metastasis. In the 36 brain metastasis cases, 19 were cases with an unknown primary. Carcinoma lung (47.2%) was found to be the most common primary malignancy. Immunohistochemistry with cytokeratin (CK)7, CK20, and thyroid transcription factor (TTF) 1 as a primary panel in metastatic tumors is highly recommended. Conclusion: Metastatic tumors accounted for 4.1% of intracranial lesions. Histopathologic pattern and immunohistochemistry aid in the accurate diagnosis of the original site of malignancy.