Authors' reply.

Sir,

Thank you for taking an interest in our article.[1] The differentials like pituitary apoplexy, cyst and hypophysitis, can easily be sorted out from pituitary metastasis by symptomatology, careful clinical examination and imaging. Metastasis occurring in preexisting adenoma leading to sudden increase in size of the tumor is a diagnostic challenge; however, the pituitary metastases usually involve neurohypophysis and stalk than adenohypophysis. Diagnosis of pituitary carcinoma is based on the presence of metastasis, either intracranial, extrasellar or extracranial.[2] In the first two cases, both had histological proven adenocarcinoma and squamous cell carcinoma, and furthermore, there was no intracranial metastasis, and hence the possibility of pituitary carcinoma is unlikely. Immunohistological markers including proliferative indices and electron microscopy can substantiate the diagnosis of pituitary metastasis; however, these were not done in our study. These cases are rare and we do not think it is the referral bias. But one should have strong suspicion when systemic malignancy is associated with pituitary enlargement. Therefore, all diagnostic modalities should be employed to prove or disprove histopathologic diagnosis of pituitary metastases in a given scenario, as the prognostic significance is different when compared to other pituitary pathologies.