Endocrine Abstracts

Introduction: Lesions of the pituitary stalk (PSL) are a challenging diagnostic problem for clinicians. Because of the critical location and role of the pituitary stalk, mass lesions in this area are not often biopsied, and the diagnosis may be based on clinical evaluation and imaging. Due to biopsy risk, about 40% PSL diagnosis are ‘probable’ or ‘unknown’.The main clinical symptoms of PSL are visual field defect, DI and hypopituitarism.

Aim: To evaluate etiology, clinical manifestations and MRI in patients (pts) with PSL who were seen at our department over 10 years.

Patients: We selected 20 pts (11 females) with abnormal pituitary stalk visualized on MRI. The mean age at diagnosis was 38.3 years ±10.2 (range, 8–67 years).

Results: Neoplastic lesions were diagnosed in 7 pts (35%): germinoma, pituicytoma, craniopharyngeoma, non-Langerhans hystiocytosis, pituitary adenoma, Rathke cyst and simple cyst one each. Distant metastatic tumors in pituitary stalk were confirmed in 3 pts (15%). Inflammatory lesion were noticed in 4 pts (20%): 2 lymphocytic infundibuloneurohypophysitis and 2 tuberculosis. Congenital anomalies were noticed in 2 pts (10%). Four patients (20%) with PSL were of unclear etiology. Tissue biopsy samples from the pituitary stalk itself were obtained in eight patients. Six pts have suffered from diabetes insipidus. Growth hormone deficiency was the most common hormone deficiency (15 pts, 75%), followed by secondary hypogonadism in 12 pts (60%) and ACTH and TSH deficiency in 8 pts (40%) each. Complete hypopituitarism was noticed in 8 pts (40%). Nine pts had visual field defect.

Conclusion: The risks associated with obtaining histological samples from the pituitary stalk, even in the group presented, the diagnosis was frequently based on other clinical findings and serial MR imaging. For the most challenging pituitary stalk lesions, an individualized approach, guided by clinical expertise, remains the best strategy.