Clinicopathological correlation in pituitary gland metastasis presenting as anterior visual pathway compression

Pituitary gland metastases, albeit rare, remain an important differential in sellar and suprasellar tumours. Clinical and radiological features of pituitary metastases may be indistinguishable from benign suprasellar lesions such as a pituitary adenoma. Histopathology with immunohistochemical assay remains the key to the diagnosis of pituitary metastasis. We describe four patients with sellar lesions presenting with anterior visual pathway compression initially diagnosed as pituitary adenomas who on immunohistochemistry were found to have metastases to the pituitary. Classification of the cell histology determined the primary site of origin in some patients. This series demonstrates the importance of combining histopathology and immunohistochemistry in the diagnosis of suprasellar lesions.