Endocrine Abstracts

Background: Cushing’s disease, the most common cause of endogenous Cushing’s syndrome, is caused by a pituitary tumor secreting adrenocorticotropic hormone (ACTH). Careful selection of treatment and management of the disease and associated comorbidities are necessary to improve prognosis.

Case Presentation: A 32-year-old patient came to our observation for appearance of weight gain with abdominal obesity, hirsutism and amenorrhea. On suspicion of Cushing’s syndrome she performed ACTH assay, cortisol h24 assay, cortisol after overnight DEX 1, Liddle’s test with no cortisol suppression, UFC suggestive of ACTH-dependent Cushing’s syndrome. The patient performed a pituitary MRI negative for pituitary adenoma. She then underwent selective lower petrous sinus catheterization with CRH test suggestive of Cushing’s disease without lateralization. An exploratory transsphenoidal neurosurgical surgery was performed with removal of small pituitary lesion with erosion of the dura mater. The histological examination documented an ACTH-secreting pituitary adenoma. Ki-67 1%. Postoperatively, the patient reported well-being, with periodic checkups documenting disease remission. After two years, the patient presented again with symptomatology suggestive of Cushing’s syndrome with appearance of biochemical recurrence of disease and pituitary MRI finding of post-surgical empty sella. Therefore, therapy with Pasireotide at a dosage of 0.6 mg subcutaneously at 2000 h. and 0.3 mg subcutaneously at 2000 h. was started. After initiation of therapy, the patient developed diabetes mellitus so hypoglycemic therapy were undertaken. In addition, pasireotide therapy was reduced to 0.3 mg twice daily based on blood and urinary cortisol dosage. The patient currently presents with target values of glycated hemoglobin and an initial hypocorticosurrenalism for which pasirotide therapy has been reduced and hydrocortisone therapy has been initiated.

Conclusions: Surgical resection of pituitary adenoma is the first-line treatment for Cushing’s disease. However, surgery is not always successful, and disease recurrence may occur years after initial remission. Repeat transsphenoidal surgery can be considered in patients with biochemical evidence of recurrent Cushing’s disease with visible tumour on MRI. Medical therapy becomes the therapy of choice in patients for whom there is no surgical target. Pasireotide is a multireceptor-targeted, second-generation somatostatin analogue with highest affinity for somatostatin receptor subtype 5 wich are expressed in corticotropinomas. The safety profile of pasireotide is similar to that of conventional somatostatin analogs, but with a higher frequency and degree of hyperglycemia. This is because pancreatic β-cells express SSTR5, which in turn regulates insulin secretion. Glucose and HbA1C levels increase immediately after the initiation of pasireotide treatment, necessitating hypoglycemic therapy.