Endocrine Abstracts

Introduction: Pituitary stalk thickening (PST) is often identified on magnetic resonance imaging (MRI), either incidentally or during diagnostic workup of hypopituitarism. Currently, there is no unified standard for the definition of PST. As a reference, a pituitary stalk with width over 3 mm has been used as the diagnostic criterion for PST in recent years. The disease spectrum of PST is quite diverse and can be grouped into three broad categories: neoplastic, inflammatory and congenital diseases. Here, we report a rare case of PST secondary to Neurosarcoidosis and pituitary metastasis of a small cell carcinoma.

Case report: We report the case of a 49 years old man with no personal medical history. The diagnosis of neuro-sarcoidosis was suspected in view of the presence of pituitary tumor syndrome, central diabetes insipidus, hypopituitarism and the presence of nodular thickening of the stalk at hypothalamic-pituitary MRI. Biological explorations had shown an increase in 1-25 OH vitamin D, a decrease in 25 OH vitamin D and a slight increase in the tumor marker NSE estimated at 42 ng/l. Chest X-ray and thoracic-abdominal CT scan were in favor of pulmonary, hepatic and adrenal involvement. Labial biopsy and bone scan were negative. To confirm the diagnosis, bronchial biopsies were performed 3 times under fibroscopic control but returned negative. Then they were redone under CT scan to conclude to a small cell lung carcinoma, but the liver biopsy was in favor of a sarcoidosis. The patient was put on replacement therapy (ddAVP at a dose of 0.1 ml*2/d, hydrocortisone at a dose of 30 mg/d and L-thyroxine at a progressive dose up to 100µg/d) with clinical and radiological monitoring. The thoracic CT scan showed an aggravation of the lesions, an increase in the tumor mass and a small pleural involvement. The diagnosis retained was that of a pituitary metastasis of a small cell carcinoma associated with sarcoidosis. Given the deterioration of the general condition and the worsening of the radiological lesions, the patient was referred to the carcinologists for vinblastine and prednisone16 - cisplatin chemotherapy. He received 3 courses of chemotherapy with a good clinical and biological evolution. Since then, the patient was regularly followed up in carcinology.