John D. Carmichael

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INTRODUCTION Biochemical efficacy of somatostatin receptor ligand (SRL) treatment in acromegaly is defined by metrics for GH and IGF-1 control. Since the earliest therapeutic trials, biochemical control criteria, medical formulations, and assay techniques have evolved. MATERIALS AND METHODS We searched PubMed for English-language trials published from(More)
Acromegaly is a rare disease characterized by excessive growth hormone secretion, usually from a pituitary tumor. Treatment options include surgery, medical therapy, and in some cases, radiation therapy. Current medical therapy consists of treatment with somatostatin analog medications or a growth hormone receptor antagonist. There are two somatostatin(More)
Ectopic pituitary adenomas are exceedingly rare entities that are often misdiagnosed. The resulting delay in diagnosis may be particularly concerning in the case of Cushing syndrome caused by an ectopic adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma. Although the total resection of ectopic adenomas results in rapid and durable remission,(More)
OBJECTIVE To assess the GH response to GHRH-arginine in apparently healthy adults in relation to cardiovascular risk factors. DESIGN Cross-sectional. PATIENTS Eighty-six male and female volunteers aged 50-90. MEASUREMENTS GH peak response to GHRH-arginine and cardiovascular risk factors, including obesity, insulin resistance, low levels of high(More)
Diagnosing Cushing's syndrome is challenging and is further hampered when investigations are performed in a patient with cyclic Cushing's syndrome. A subset of patients with Cushing's syndrome exhibit periods of abnormal cortisol secretion with interspersed normal secretion. Patients can have periods of clinical improvement during these quiescent phases or(More)
OBJECT Functional corticotroph pituitary adenomas (PAs) secrete adrenocorticotropic hormone (ACTH) and are the cause of Cushing's disease, which accounts for 70% of all cases of Cushing's syndrome. Current classification systems for PAs rely primarily on laboratory hormone findings, tumor size and morphology, invasiveness, and immunohistochemical findings.(More)
BACKGROUND The study aim was to estimate the proportion of acromegaly patients with various comorbidities and to determine if biochemical control was associated with reduced proportion of cardiovascular risk factors. METHODS Data were from a single-center acromegaly registry. Study patients were followed for ≥12 months after initial treatment. Study(More)
BACKGROUND Long-term remission rates from endoscopic transsphenoidal surgery for acromegaly and their relationship to prognostic indicators of disease aggressiveness are not well documented. OBJECTIVE To investigate long-term remission rates in patients with acromegaly after endoscopic transsphenoidal surgery, and correlate this with molecular and(More)
OBJECTIVE Craniopharyngiomas and similar midline suprasellar tumors have traditionally been resected via transcranial approaches. More recently, expanded endoscopic endonasal transsphenoidal approaches have gained interest. Surgeons have advocated for both approaches, and at present there is no consensus whether one approach is superior to the other. The(More)
BACKGROUND Pituitary carcinoma is extremely rare, representing approximately 0.2% of all surgically resected pituitary neoplasms. It is thought to arise from World Health Organization grade II (atypical) pituitary adenomas. Pituitary carcinoma is defined by metastasis; it is otherwise indistinguishable from atypical pituitary adenomas, which can be(More)