Endocrine Abstracts

Background: Pituitary metastasis are rare, however, not well-documented. They are usually encountered in elderly patients with disseminated malignant disease. The most frequent are metastases of breast and lung cancer. We herein report a case of an old patient with pituitary metastasis of a mediastinal lymphoma.

Case report: A 88-year-old man with a history of treated prostate cancer and primary hypothyroidism presented to our emergency department with headaches, asthenia and fast progressing bilateral paraplegia. Thoraco abdominal computed tomographic (CT) scan detected a large mass of 73*70*180 mm at the posterior mediastinum with multiple pleural and vertebral metastases. The 18F-FDG-TEP scan confirmed the mediastinal mass wich was intensely hypermetabolic and revealed an intensely hypermetabolic mass in the pituitary fossa (SUV max 16.8). Magnetic resonance imaging of the pituitary revealed a sellar mass of 15*9*14 mm involving the pituitary gland which is also extended into the right cavernous sinus. Laboratory tests indicated an elevated LDH level,a normochromic and normocytic anemia of 10 g/dl, a lymphopenia and a normal hormonal profile. A CT-guided biopsy of the mediastinal mass was done and the histological examination revealed that it was the infiltration of a large B-cell lymphoma. Diagnosis of the pituitary metastasis was made by identification of lymphomatous cells in the cerebrospinal fluid. Chemotherapy was then initiated.

Conclusion: This case illustrated a rare cause of pituitary metastasis: the non Hodgkinien lymphoma. This diagnosis is usually difficult to differentiate from pituitary adenoma, meningioma and other sellar lesions. An earlier diagnosis may lead to an appropriate therapy and potentially improving quality of life.