Twelve cases of pituitary metastasis: a case series and review of the literature

Purpose: The pituitary gland is an unusual site for metastatic spread, but as patients with metastatic malignancy are living longer, it may become more prevalent. Compression of important anatomy adjacent to the sella may produce disabling symptoms and endocrine derangement, leading to significant morbidity. Methods: An ambispective review of patient records between 2013 and 2017 from three neurosurgical centres was performed. After identifying cases, further investigation was performed to evaluate patient demographic, symptoms at presentation, radiological and histological findings, management, and outcome. Results: Our investigation identified 12 patients with pituitary metastasis. The average age of the cases was 63.4 years, with breast (n = 4) and lung (n = 4) being the most common primary cancers. In half the cases there was a history of metastatic disease, while in one-quarter of cases, pituitary symptoms were the first sign of malignancy. Adenohypophyseal dysfunction (83%), diabetes insipidus (DI) (75%), headache (67%) and visual field defects (67%) were the most common findings at presentation. Glucocorticoid replacement increased the sensitivity for diagnosis of DI. All cases were contrast enhancing on MRI and the endoscopic trans-sphenoidal approach was preferred for biopsy and debulking. Conclusions: The pituitary should not be overlooked as a site of metastasis and sellar symptoms may be the first presentation of neoplastic disease. Any biochemical or clinical sign of pituitary pathology in a patient with known cancer should raise suspicion for sellar metastasis. Moreover, the development of DI or ophthalmoplegia from any pituitary lesion is suggestive of metastatic disease even in patients with no known primary.