Lynnette K. Nieman

Cushing's syndrome

Chronic exposure to excess glucorticoids results in diverse manifestations of Cushings syndrome, including debilitating morbidities and increased mortality. Genetic and molecular mechanisms responsible for excess cortisol secretion by primary adrenal lesions and adrenocorticotropic hormone (ACTH) secretion from corticotroph or ectopic tumours have been identified. New biochemical and imaging diagnostic approaches and progress in surgical and radiotherapy techniques have improved the management of patients. The therapeutic goal is to normalise tissue exposure to cortisol to reverse increased morbidity and mortality. Optimum treatment consisting of selective and complete resection of the causative tumour is necessay to allow eventual normalisation of the hypothalamic-pituitary-adrenal axis, maintenance of pituitary function, and avoidance of tumour recurrence. The development of new drugs offers clinicians several choices to treat patients with residual cortisol excess. However, for patients affected by this challenging syndrome, the long-term effects and comorbidities associated with hypercortisolism need ongoing care.

The Diagnosis of Cushing's Syndrome: An Endocrine Society Clinical Practice Guideline

OBJECTIVE The objective of the study was to develop clinical practice guidelines for the diagnosis of Cushings syndrome. PARTICIPANTS The Task Force included a chair, selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society, five additional experts, a methodologist, and a medical writer. The Task Force received no corporate funding or remuneration. CONSENSUS PROCESS Consensus was guided by systematic reviews of evidence and discussions. The guidelines were reviewed and approved sequentially by The Endocrine Societys CGS and Clinical Affairs Core Committee, members responding to a web posting, and The Endocrine Society Council. At each stage the Task Force incorporated needed changes in response to written comments. CONCLUSIONS After excluding exogenous glucocorticoid use, we recommend testing for Cushings syndrome in patients with multiple and progressive features compatible with the syndrome, particularly those with a high discriminatory value, and patients with adrenal incidentaloma. We recommend initial use of one test with high diagnostic accuracy (urine cortisol, late night salivary cortisol, 1 mg overnight or 2 mg 48-h dexamethasone suppression test). We recommend that patients with an abnormal result see an endocrinologist and undergo a second test, either one of the above or, in some cases, a serum midnight cortisol or dexamethasone-CRH test. Patients with concordant abnormal results should undergo testing for the cause of Cushings syndrome. Patients with concordant normal results should not undergo further evaluation. We recommend additional testing in patients with discordant results, normal responses suspected of cyclic hypercortisolism, or initially normal responses who accumulate additional features over time.

Neuroendocrine tumors of the lung with proposed criteria for large-cell neuroendocrine carcinoma. An ultrastructural, immunohistochemical, and flow cytometric study of 35 cases.

Based on our review of 35 cases and the literature, we found the spectrum of pulmonary neuroendocrine (NE) tumors to be too broad to fit into the traditional threecategory classification scheme of typical carcinoid (TC), atypical carcinoid (AC), and small-cell lung carcinoma (SCLC). We found that a spectrum of high-and low-grade tumors exist between TC and SCLC and that in the past many of these tumors have been called AC. We chose to adhere to Arrigonis definition of AC, as his original criteria characterized a low-grade tumor. For the higher grade non-small-cell tumors (NSCLC), we propose a fourth category of large-cell neuroendocrine carcinoma (LCNEC), which is characterized by: (a) light microscopic NE appearance; (b) cells of large size, polygonal shape, low nuclear-cytoplasmic ratio (N:C), coarse nuclear chromatin, and frequent nucleoli; (c) high mitotic rate [> 10/10 high-power fields (HPF)] and frequent necrosis; and (d) NE features by immunohistochemistry (IHC) or electron microscopy (EM). Thus, after deciding that a pulmonary NE tumor is high grade, the major diagnostic issue is separation of LCNEC from SCLC. This distinction is based not only on cell size, but on a variety of morphologic features. We studied 20 TC, six AC, five LCNEC, and four SCLC and characterized the clinical, light microscopic, EM, IHC, and flow cytometric features of each type of tumor. We did not find any advantage to IHC. EM, or flow cytometry over light microscopy in the subclassification or prediction of prognosis; however, these methods were useful in characterizing these four types of pulmonary NE tumors and in demonstrating their NE properties. LCNEC must be distinguished from a fifth category pulmonary NE tumor: NSCLC with NE features in which NE differentiation is not evident by light microscopy and must be demonstrated by EM or IHC. Although the prognosis of LCNEC appears to be intermediate between AC and SCLC, larger numbers of patients will be needed to demonstrate significant differences in survival.

Responses to corticotropin-releasing hormone in the hypercortisolism of depression and Cushing's disease. Pathophysiologic and diagnostic implications.

Primary depression can be associated with substantial hypercortisolism, thus prompting some researchers to suggest that depression shares pathophysiologic features with Cushings disease. Clinically, depression can be difficult or impossible to distinguish from mild or early Cushings disease that is associated with depressive features. The purpose of this study was to evaluate whether the pituitary-adrenal responses to ovine corticotropin-releasing hormone could help to clarify the mechanism of hypercortisolism in depression and in Cushings disease and to assist in the differential diagnosis of these disorders. As compared with controls (n = 34), depressed patients (n = 30) had basal hypercortisolism (P less than 0.001) that was associated with attenuated plasma ACTH responses to ovine corticotropin-releasing hormone (P less than 0.001). This indicates that in patients with depression, the corticotroph cell in the pituitary responds appropriately to the negative feedback of high cortisol levels. In contrast, patients with Cushings disease (n = 29) had plasma ACTH hyperresponsiveness to ovine corticotropin-releasing hormone (P less than 0.001), despite basal hypercortisolism (P less than 0.001), which indicates a gross impairment of the mechanism by which cortisol exerts negative feedback on the pituitary. Less than 25 percent of the patients with depression or Cushings disease had peak ACTH responses that overlapped. We conclude that the pathophysiologic features of hypercortisolism in depression and Cushings disease are distinct in each of the disorders and that the ovine corticotropin-releasing hormone stimulation test can be helpful in their differential diagnosis.

Petrosal Sinus Sampling with and without Corticotropin-Releasing Hormone for the Differential Diagnosis of Cushing's Syndrome

BACKGROUND Measurement of adrenocorticotropin levels in plasma from the inferior petrosal sinuses of patients with Cushings syndrome can distinguish adrenocorticotropin-secreting pituitary tumors (Cushings disease) from other causes of the syndrome, principally ectopic adrenocorticotropin secretion from an occult tumor. However, it is unknown whether such measurement consistently identifies patients with Cushings disease and whether testing with corticotropin-releasing hormone (CRH) enhances the value of the procedure. METHODS We prospectively studied 281 patients with Cushings syndrome to evaluate the diagnostic efficacy of the procedure. Bilateral sampling was successfully accomplished in 278 patients, with no major morbidity; 262 of these patients underwent sampling before and after administration of ovine CRH. The adrenocorticotropin levels in the samples were used to calculate the ratio of the concentration in plasma from the inferior petrosal sinuses to the concentration in peripheral-blood plasma (the IPS:P ratio). RESULTS The diagnosis of 246 patients was confirmed surgically as Cushings disease in 215, as ectopic adrenocorticotropin syndrome in 20, and as primary adrenal disease in 11. An IPS:P ratio greater than or equal to 2.0 in basal samples identified 205 of the 215 patients with Cushings disease (sensitivity, 95 percent), with no false positive results (specificity, 100 percent). A peak IPS:P ratio greater than or equal to 3.0 after CRH administration identified all 203 of the patients with Cushings disease who received CRH (sensitivity, 100 percent), with no false positive results (specificity, 100 percent). The sensitivity was much lower when the adrenocorticotropin concentrations in the samples from one sinus were considered alone. In patients with Cushings disease a difference of greater than or equal to 1.4-fold between the concentrations in the two sinuses (the adrenocorticotropin gradient) predicted the location of the microadenoma in 68 percent of 104 patients during basal sampling and in 71 percent of 105 patients after CRH administration. CONCLUSIONS Simultaneous bilateral sampling of plasma from the inferior petrosal sinuses, with the adjunctive use of CRH, distinguishes patients with Cushings disease from those with ectopic adrenocorticotropin secretion with high diagnostic accuracy.

Treatment of Adrenocorticotropin-Dependent Cushing’s Syndrome: A Consensus Statement

OBJECTIVE Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushings syndrome, because there is no recent consensus on the management of this rare disorder. PARTICIPANTS Thirty-two leading endocrinologists, clinicians, and neurosurgeons with specific expertise in the management of ACTH-dependent Cushings syndrome representing nine countries were chosen to address 1) criteria for cure and remission of this disorder, 2) surgical treatment of Cushings disease, 3) therapeutic options in the event of persistent disease after transsphenoidal surgery, 4) medical therapy of Cushings disease, and 5) management of ectopic ACTH syndrome, Nelsons syndrome, and special patient populations. EVIDENCE Participants presented published scientific data, which formed the basis of the recommendations. Opinion shared by a majority of experts was used where strong evidence was lacking. CONSENSUS PROCESS Participants met for 2 d, during which there were four chaired sessions of presentations, followed by general discussion where a consensus was reached. The consensus statement was prepared by a steering committee and was then reviewed by all authors, with suggestions incorporated if agreed upon by the majority. CONCLUSIONS ACTH-dependent Cushings syndrome is a heterogeneous disorder requiring a multidisciplinary and individualized approach to patient management. Generally, the treatment of choice for ACTH-dependent Cushings syndrome is curative surgery with selective pituitary or ectopic corticotroph tumor resection. Second-line treatments include more radical surgery, radiation therapy (for Cushings disease), medical therapy, and bilateral adrenalectomy. Because of the significant morbidity of Cushings syndrome, early diagnosis and prompt therapy are warranted.

Differential Behavioral Effects of Gonadal Steroids in Women with and in Those without Premenstrual Syndrome

BACKGROUND The symptoms of women with premenstrual syndrome improve in response to suppression of ovarian function, although these women have no evidence of ovarian dysfunction. We undertook a study to determine the role of estrogen and progesterone in this syndrome. METHODS We first studied the effect of ovarian suppression with leuprolide, an agonist analogue of gonadotropin-releasing hormone, or placebo on symptoms in 20 women with the premenstrual syndrome. Ten women whose symptoms improved during leuprolide treatment were given estradiol and progesterone in a double-blind, crossover design, each for four weeks, during continued leuprolide administration. Women without premenstrual syndrome (normal women) participated in a similar protocol. Outcomes were assessed on the basis of daily self-reports by the patients and biweekly rater-administered symptom-rating scales. RESULTS The 10 women with premenstrual syndrome who were given leuprolide had a significant decrease in symptoms as compared with base-line values and with values for the 10 women who were given placebo. The 10 women with premenstrual syndrome who were given leuprolide plus estradiol or progesterone had a significant recurrence of symptoms, but no changes in mood occurred in 15 normal women who received the same regimen or in 5 women with premenstrual syndrome who were given placebo hormone during continued leuprolide administration. CONCLUSIONS In women with premenstrual syndrome, the occurrence of symptoms represents an abnormal response to normal hormonal changes.

Abnormal hypothalamic-pituitary-adrenal function in anorexia nervosa: pathophysiologic mechanisms in underweight and weight-corrected patients

To study the pathophysiology of hypercortisolism in patients with anorexia nervosa, we examined plasma ACTH and cortisol responses to ovine corticotropin-releasing hormone before and after correction of weight loss. We also studied patients with bulimia whose weight was normal, since this disorder has been suspected to be a variant of anorexia nervosa. Before their weight loss was corrected, the anorexic patients had marked hypercortisolism but normal basal plasma ACTH. The hypercortisolism was associated with a marked reduction in the plasma ACTH response to corticotropin-releasing hormone. When these patients were studied three to four weeks after their body weight had been restored to normal, the hypercortisolism had resolved but the abnormal response to corticotropin-releasing hormone remained unchanged. On the other hand, at least six months after correction of weight loss their responses were normal. The bulimic patients whose weight was normal also had a normal response to corticotropin-releasing hormone. We conclude that in underweight anorexics, the pituitary responds appropriately to corticotropin-releasing hormone, being restrained in its response by the elevated levels of cortisol. This suggests that hypercortisolism in anorexics reflects a defect at or above the hypothalamus. The return to eucortisolism soon after correction of the weight loss indicates resolution of this central defect despite persistence of abnormalities in adrenal function.

Cushing's Syndrome in Children and Adolescents -- Presentation, Diagnosis, and Therapy

BACKGROUND AND METHODS Cushings syndrome is rare in children and adolescents. We analyzed the clinical presentation, diagnostic evaluation, and treatment of 59 patients with Cushings syndrome between the ages of 4 and 20 years who were admitted to the National Institutes of Health during the period from 1982 to 1992. The cause of hypercortisolism was identified by low- and high-dose dexamethasone suppression tests, the ovine corticotropin-releasing hormone (CRH) stimulation test, imaging studies, and bilateral sampling of the inferior petrosal sinuses combined with administration of CRH. RESULTS Fifty patients had Cushings disease, six had primary adrenal disease, and three had ectopic corticotropin secretion. The initial signs were excessive weight gain in 90 percent of the patients and growth retardation in 83 percent. Most patients (81 percent) had normal bone age at the time of diagnosis. Forty-seven percent had hypertension, whereas only 19 percent had mental or behavioral problems. The high-dose dexamethasone suppression test and the CRH stimulation test identified 68 and 80 percent, respectively, of the patients with Cushings disease. Magnetic resonance imaging of the pituitary indicated the presence of tumor in 52 percent of the patients with pituitary adenomas. The maximal central-to-peripheral ratio of plasma corticotropin during sampling of the interior petrosal sinuses was > or = 2.5 in all the patients with Cushings disease and < 2.5 in those with ectopic corticotropin secretion. Remission of hypercortisolism was achieved in 48 of the 49 patients who underwent transsphenoidal surgery for Cushings disease, in all 6 of the patients who underwent adrenalectomy for primary adrenal disease, and in the 2 patients in whom the ectopic source of corticotropin could be identified. CONCLUSIONS Weight gain and growth retardation are common clinical characteristics of Cushings syndrome in children and adolescents. Diagnostic evaluation of such patients with CRH stimulation alone and combined with inferior petrosal sinus sampling and imaging studies is accurate, and therapy is usually successful.

Treatment of Cushing's Syndrome: An Endocrine Society Clinical Practice Guideline.

OBJECTIVE The objective is to formulate clinical practice guidelines for treating Cushings syndrome. PARTICIPANTS Participants include an Endocrine Society-appointed Task Force of experts, a methodologist, and a medical writer. The European Society for Endocrinology co-sponsored the guideline. EVIDENCE The Task Force used the Grading of Recommendations, Assessment, Development, and Evaluation system to describe the strength of recommendations and the quality of evidence. The Task Force commissioned three systematic reviews and used the best available evidence from other published systematic reviews and individual studies. CONSENSUS PROCESS The Task Force achieved consensus through one group meeting, several conference calls, and numerous e-mail communications. Committees and members of The Endocrine Society and the European Society of Endocrinology reviewed and commented on preliminary drafts of these guidelines. CONCLUSIONS Treatment of Cushings syndrome is essential to reduce mortality and associated comorbidities. Effective treatment includes the normalization of cortisol levels or action. It also includes the normalization of comorbidities via directly treating the cause of Cushings syndrome and by adjunctive treatments (eg, antihypertensives). Surgical resection of the causal lesion(s) is generally the first-line approach. The choice of second-line treatments, including medication, bilateral adrenalectomy, and radiation therapy (for corticotrope tumors), must be individualized to each patient.