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J L Doppman

Publications and source records attributed to J L Doppman.

At least 55 records · Page 3Linked to original sources

Plasma levels of corticotropin-releasing hormone in the inferior petrosal sinuses of healthy volunteers, patients with Cushing's syndrome, and patients with pseudo-Cushing states.

The objective of this study was to determine whether measurements of human CRH in the inferior petrosal sinuses could distinguish patients with Cushing's syndrome from those with pseudo-Cushing states or normal physiology. Twenty-five patients with Cushing's disease, 17 patients with the syndrome of ectopic ACTH, 7 patients with Cushing's syndrome of adrenal origin, 6 patients with pseudo-Cushing states, and 11 volunteers believed to have normal hypothalamic-pituitary-adrenal axes were studied. Basal plasma human CRH and ACTH were measured at two time points in the petrosal sinuses and in a peripheral vein. Most subjects were studied after the administration of intravenous diazepam or midazolam and fentanyl, but because of the known inhibitory effects of such sedation on CRH secretion, 2 normal volunteers and 3 patients with pseudo-Cushing states were studied without sedation. Human CRH levels were near or below the detection limit of the assay in all subjects. Although the normal volunteers and patients with pseudo-Cushing states who were studied without sedation had significantly greater inferior petrosal sinus ACTH levels than those who received sedation, there were no differences in measured human CRH levels for any of the groups. We conclude that inferior petrosal sinus human CRH levels are not easily measured in the inferior petrosal sinuses and cannot be used to determine whether individual patients may have hypersecretion of CRH causing their ACTH secretion.

Adrenocorticotropic Hormone↗

Localization of pituitary adenomas by using intraoperative ultrasound in patients with Cushing's disease and no demonstrable pituitary tumor on magnetic resonance imaging.

OBJECT: Pituitary surgery has been reported to produce remission of Cushing's disease with preservation of pituitary function in only 60 to 70% of patients. The inability to identify an adenoma accounts for most failed sellar explorations. Most negative surgical explorations occur in patients in whom magnetic resonance (MR) imaging of the pituitary demonstrates normal findings, which happens in at least 35 to 45% of patients with Cushing's disease. METHODS: To examine the usefulness of intraoperative ultrasonography (IOUS) for identifying an adenoma in patients with no demonstrable tumor (negative findings) on pituitary MR imaging. we prospectively assessed the results of IOUS in 68 patients with a negative (59 patients) or equivocal (nine patients) MR image from a consecutive series of 107 patients with Cushing's disease (64%). We compared surgical findings and outcomes in these 68 patients with a group of 68 patients with Cushing's disease and negative findings on MR imaging in whom IOUS was not available. Intraoperative ultrasonography localized a tumor in 47 (69%) of 68 patients with negative findings on MR imaging. Surprisingly, the size of the adenomas that were detected with IOUS compared with the size of those not detected did not differ (6.8+/-3.4 mm compared with 6.1+/-2.8 mm [mean+/-standard deviation], respectively [p=0.51). In four patients, no adenoma was found at surgery or in the pathological specimen ("true negative"). In eight patients, nine abnormalities detected by IOUS that were suspected adenomas were negative on exploration ("false positive"). Thus, IOUS has a sensitivity of 73% and a positive predictive value of 84% for detecting pituitary adenomas in patients with Cushing's disease and negative findings on MR imaging. Compared with the 68 patients who did not undergo IOUS. remission after surgery was improved (61 patients [90%] compared with 57 patients [84%]), the number of tumors found on exploration was increased (61 tumors compared with 51 tumors, p=0.02), and the number of hemihypophysectomies was decreased (five compared with 15; p=0.02) with IOUS. When the groups were compared after excluding patients with prior pituitary surgery, tumors were found in 91% versus 72% (p=0.008), and remission occurred in 95% versus 87% of patients, respectively, in the groups that had or did not have IOUS. CONCLUSIONS: The IOUS is a sensitive imaging modality when used in patients with Cushing's disease in whom findings on pituitary MR imaging are negative. The improved ability to detect and localize these tumors by using IOUS positively affects surgical outcome.

Adenoma↗

A prospective analysis of the frequency, location, and curability of ectopic (nonpancreaticoduodenal, nonnodal) gastrinoma.

BACKGROUND: Extrapancreatic, extraduodenal and extralymphatic (ectopic) gastrinomas have been reported only rarely. The frequency, locations, and surgical outcome of these lesions are unknown. METHODS: From 1982 to 1997, 215 patients with Zollinger-Ellison syndrome were evaluated prospectively at the National Institutes of Health and 142 patients (66%) underwent standardized surgical exploration and resection. Eight patients (5.6%) (six men and two women; mean age, 41 years) had primary gastrinoma located in ectopic sites. Long-term follow-up was derived from a prospective database. RESULTS: Ectopic gastrinoma tissue was identified and resected in the liver (three patients), common bile duct (one patient), jejunum (one patient), omentum (one patient), pylorus (one patient), and ovary (one patient). Seven patients (88%) were cured biochemically after resection and five patients (63%) have sustained cures, with a mean follow-up of 7.5 years (range, 0.4 to 11.7 years). One patient with a jejunal primary gastrinoma had a biochemical recurrence at 2 years, and another with a primary hepatic gastrinoma had a recurrence 6 years after resection. A patient with a pyloric primary gastrinoma was not cured. CONCLUSIONS: Extraduodenal, extrapancreatic, and extranodal gastrinomas are encountered in 5.6% of patients who undergo exploration with curative intent. If no gastrinoma is found in the usual locations, other ectopic sites should be examined carefully. Resection of these primary ectopic tumors can lead to durable biochemical cures.

Adult↗

The role of thyroid resection during reoperation for persistent or recurrent hyperparathyroidism.

BACKGROUND: The role of "blind" thyroid lobectomy in the surgical management of patients with persistent or recurrent primary hyperparathyroidism is not known. We reviewed our experience with reoperation for hyperparathyroidism to determine the utility of blind thyroid resection in this setting. METHODS: From 1982 to 1995, 269 patients underwent reoperation for hyperparathyroidism at our institution. All patients had biochemical confirmation of hyperparathyroidism and underwent noninvasive and if necessary invasive localization studies. Patients who underwent thyroid lobectomy in an attempt to extirpate the hyperfunctioning parathyroid gland form the basis of this report. RESULTS: Thirty-two of 269 patients (12%) underwent thyroid lobectomy to remove a parathyroid gland. Intrathyroidal parathyroids were confirmed in 19 of 32 patients (59%). In 18 of 19 patients (94%), preoperative or intraoperative ultrasonography correctly identified an intrathyroidal lesion suspicious or a parathyroid. Only 1 of 6 patients (17%) undergoing a blind thyroidectomy had an intrathyroidal gland identified. Ultrasonography had a sensitivity of 95% and a negative predictive value of 99.5% in detecting an intrathyroidal parathyroid gland. CONCLUSIONS: The prevalence of an intrathyroidal parathyroid gland in our series is low (19 of 269, 7%). Ultrasonography can be used reliably to select patients for thyroid resection, reducing the need to perform a blind thyroid lobectomy and avoiding the potential morbidity of thyroid resection in this clinical setting.

Adolescent↗

Intraarterial calcium stimulation and intraoperative ultrasonography in the localization and resection of insulinomas.

BACKGROUND: Standard imaging studies (computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, ultrasonography, and angiography) correctly localize insulinomas in less than 50% of patients and provide no information about the feasibility of enucleation based on proximity of tumor to pancreatic duct. We reviewed our experience with intraarterial calcium stimulation (Ca-Stim) and intraoperative ultrasonography (IOUS) to localize and guide management of insulinomas. METHODS: Thirty-six patients (14 men, 22 women, median age 44 years) with insulinomas were treated between August 1989 and June 1996. Preoperative imaging studies were obtained. Patients underwent abdominal exploration with IOUS. Fourteen were evaluated by a surgeon blinded to preoperative imaging results. RESULTS: Tumors (4 to 50 mm) were resected by enucleation (67%) or partial pancreatectomy (33%); all were cured. Sensitivities of computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, ultrasonography, angiography, and Ca-Stim in localizing insulinomas were 24%, 45%, 17%, 13%, 43%, and 94%, respectively. Tumors were identified by blinded surgical exploration with IOUS in 12 of 14 patients (86%). CONCLUSIONS: All insulinomas were identified before operation; however sensitivity of individual noninvasive tests was low (less than 50%). In contrast, Ca-Stim was correct in 94% of cases, thus allowing a focused pancreatic exploration and obviating use of blind distal pancreatectomy. IOUS can then be used to guide safe enucleation.

Adolescent↗

Problems in endocrinologic imaging.

Imaging particularly cross-sectional computer-assisted techniques such as CT and MR imaging, has become so refined and even breathtaking that the display of anatomy is beguiling endocrinologists into an unhealthy reliance on visual data. The demonstration of a focal abnormality in an endocrine gland tells us nothing about its function. Overreliance on such displays of anatomy leads to problems in diagnosis and treatment. This article points out some instances in which imaging is deceptive.

Adrenal Gland Neoplasms↗

Somatic mutation of the MEN1 gene in parathyroid tumours.

Primary hyperparathyroidism is a common disorder with an annual incidence of approximately 0.5 in 1,000 (ref. 1). In more than 95% of cases, the disease is caused by sporadic parathyroid adenoma or sporadic hyperplasia. Some cases are caused by inherited syndromes, such as multiple endocrine neoplasia type 1 (MEN1; ref. 2). In most cases, the molecular basis of parathyroid neoplasia is unknown. Parathyroid adenomas are usually monoclonal, suggesting that one important step in tumour development is a mutation in a progenitor cell. Approximately 30% of sporadic parathyroid tumours show loss of heterozygosity (LOH) for polymorphic markers on 11q13, the site of the MEN1 tumour suppressor gene. This raises the question of whether such sporadic parathyroid tumours are caused by sequential inactivation of both alleles of the MEN1 gene. We recently cloned the MEN1 gene and identified MEN1 germline mutations in fourteen of fifteen kindreds with familial MEN1 (ref. 10). We have studied parathyroid tumours not associated with MEN1 to determine whether somatic mutations in the MEN1 gene are present. Among 33 tumours we found somatic MEN1 gene mutation in 7, while the corresponding MEN1 germline sequence was normal in each patient. All tumours with MEN1 gene mutation showed LOH on 11q13, making the tumour cells hemi- or homozygous for the mutant allele. Thus, somatic MEN1 gene mutation for the mutant allele. Thus, somatic MEN1 gene mutation contributes to tumorigenesis in a substantial number of parathyroid tumours not associated with the MEN1 syndrome.

Chromosomes, Human, Pair 11↗

Inferior petrosal sinus AVP in patients with Cushing's syndrome.

OBJECTIVE: In both normal volunteers and patients with Cushing's disease, one dominant inferior petrosal sinus (IPS) contains higher concentrations of AVP and ACTH than the contralateral (non-dominant) IPS, but ovine corticotrophin-releasing hormone (oCRH)-stimulated AVP in the petrosal sinuses is greater in Cushing's disease than in normal volunteers. To distinguish whether greater oCRH-releasable AVP might be specifically related to the presence of a pituitary corticotrophinoma, or be due to hypercortisolism per se, we compared IPS AVP in patients with Cushing's disease with those of patients with other causes of Cushing's syndrome. PATIENTS: Twenty-three patients with Cushing's disease, 16 patients with the syndrome of ectopic ACTH and seven patients with Cushing's syndrome of adrenal origin. MEASUREMENTS: AVP and ACTH, measured both before and 3, 5 and 10 minutes after oCRH in the petrosal sinuses, and in a peripheral vein. RESULTS: In all three groups, AVP concentrations were lateralized such that most of the AVP was found in one, dominant IPS. oCRH significantly increased IPS ACTH only in patients with Cushing's disease (p < 0.001), whereas it significantly increased dominant IPS AVP levels in all three patient groups (P < 0.01). However, neither dominant nor non-dominant IPS AVP (basal or oCRH-stimulated) were significantly different among patients with Cushing's disease, ectopic ACTH or Cushing's syndrome of adrenal origin. Basal and oCRH-stimulated IPS AVP were negatively correlated with urine free cortisol. CONCLUSIONS: Inferior petrosal sinus AVP levels are similar in all forms of Cushing's syndrome, and thus the higher inferior petrosal sinus AVP levels in patients with Cushing's disease compared with normal volunteers are unlikely to be related specifically to the presence of the pituitary corticotrophinoma. While AVP may play a role in pituitary corticotroph tumourigenesis or may be secreted by some pituitary corticotroph tumours, the observation that CRH-stimulated inferior petrosal sinus AVP levels are higher in Cushing's disease than in normal volunteers appears most likely to be related to the low endogenous CRH levels induced by hypercortisolism, rather than a consequence of Cushing's disease itself. We hypothesize that low endogenous CRH leads to increased sensitivity of central nervous system CRH receptors to exogenous CRH, and thus to greater ovine CRH-stimulated AVP.

ACTH Syndrome, Ectopic↗

Value of somatostatin receptor scintigraphy: a prospective study in gastrinoma of its effect on clinical management.

BACKGROUND & AIMS: Recently [111In-DTPA-D-Phe1]-octreotide was approved for somatostatin receptor scintigraphy (SRS) of gastroenteropancreatic tumors. SRS and other tumor localization methods can be time consuming, expensive, and involve patient inconvenience. The role of SRS in comparison to other tumor localization modalities remains undefined because the relative effects of these methods on management have not been studied. The aim of this study was to determine whether SRS alters clinical management in Zollinger-Ellison syndrome. METHODS: One hundred twenty-two consecutive patients were studied prospectively. Each patient was assigned to one of five different clinical categories. Conventional imaging studies (ultrasonography, computerized tomography, magnetic resonance image, angiography, and bone scan) were performed, and the management was proposed. SRS was then performed. Clinical management was reassessed, and whether SRS altered management was determined based on six criteria. RESULTS: SRS was superior to any single imaging study. SRS altered management in 47% overall and in 22%-60% of patients in the five different clinical categories. Primary tumor localization and clarification of equivocal localization results from conventional studies were the principal reasons for altering management. SRS was equally useful in patients with or without metastatic liver disease. CONCLUSIONS: Because of the ability of SRS to alter clinical management combined with its superior sensitivity, high specificity, simplicity, and cost-effectiveness, SRS should be the initial imaging modality for patients with gastrinomas.

Adult↗

Primary cardiac gastrinoma causing Zollinger-Ellison syndrome.

Primary cardiac tumors are rare, and there are no reports of patients with a functional gastroenteropancreatic tumor syndrome caused by such a tumor. This case report describes a patient with a cardiac gastrinoma causing Zollinger-Ellison syndrome. Evidence is presented that this tumor represents a primary cardiac tumor. The exact identification of this gastrinoma in an extra-abdominal site was facilitated by the use of [111In-DTPA-DPhe1]octreotide scanning for somatostatin receptors, which these tumors characteristically possess in high numbers. The recent availability of this novel localization method may facilitate identification of extra-abdominal sites in an increasing proportion of patients with gastrinomas and related neuroendocrine functional tumors in which no intra-abdominal primary tumor is currently found.

Adolescent↗

Germline mutations of the MEN1 gene in familial multiple endocrine neoplasia type 1 and related states.

Familial multiple endocrine neoplasia type 1 (FMEN1) is an autosomal dominant trait characterized by tumors of the parathyroids, gastro-intestinal endocrine tissue, anterior pituitary and other tissues. We recently cloned the MEN1 gene and confirmed its identity by finding mutations in FMEN1. We have now extended our mutation analysis to 34 more unrelated FMEN1 probands and to two related states, sporadic MEN1 and familial hyperparathyroidism. There was a high prevalence of heterozygous germline MEN1 mutations in sporadic MEN1 (8/11 cases) and in FMEN1 (47/50 probands). One case of sporadic MEN1 was proven to be a new MEN1 mutation. Eight different mutations were observed more than once in FMEN1. Forty different mutations (32 FMEN1 and eight sporadic MEN1) were distributed across the MEN1 gene. Most predicted loss of function of the encoded menin protein, supporting the prediction that MEN1 is a tumor suppressor gene. No MEN1 germline mutation was found in five probands with familial hyperparathyroidism, suggesting that familial hyperparathyroidism often is caused by mutation in another gene or gene(s).

Adult↗

Distinguishing small hepatic hemangiomas from vascular liver metastases in gastrinoma: use of a somatostatin-receptor scintigraphic agent.

PURPOSE: To compare somatostatin-receptor scintigraphy and conventional imaging modalities in the differentiation of small hepatic hemangiomas from small liver metastases in Zollinger-Ellison syndrome. MATERIALS AND METHODS: Twenty-nine patients had hypervascular liver lesions smaller than 2 cm that could have been either metastases or hemangiomas. Fourteen patients had metastases, 14 had hemangiomas, and one had both. Scintigraphy was compared with computed tomography (CT), magnetic resonance (MR) imaging, and angiography for the correct identification of the lesions. RESULTS: The hemangiomas and liver metastases both had a mean size of 1.3 cm. In the patients with hepatic hemangiomas, scintigraphy showed no lesions. CT, angiography, or MR imaging showed a lesion in 40%-93%. With metastases present, any liver lesion was detected in 93% with scintigraphy versus 20%-60% with another modality. Scintigraphy depicted liver metastases in 93% of patients, which was higher than the sensitivities of other modalities. The accuracy (96%) and positive (100%) and negative (93%) predictive values of scintigraphy for detecting liver metastases were superior to those of other modalities. There were 45 liver metastases and 31 hemangiomas; a per lesion analysis gave results similar to the per patient analysis results. CONCLUSION: In Zollinger-Ellison syndrome, somatostatin-receptor scintigraphy provides an excellent diagnostic tool to differentiate small hepatic hemangiomas from small liver metastases.

Adult↗

Growth of newly diagnosed, untreated metastatic gastrinomas and predictors of growth patterns.

PURPOSE: The growth pattern of untreated metastatic neuroendocrine tumors is unknown. This uncertainty contributes to the disagreement regarding timing and could effect evaluation of the efficacy of antitumor treatment. The purpose of this study was to determine the growth rate of untreated hepatic metastatic gastrinoma and to identify its predictors. PATIENTS AND METHODS: Nineteen patients with histologically proven metastatic gastrinoma in the liver with Zollinger-Ellison syndrome were studied. Conventional imaging studies were performed initially and at 4- to 6-month intervals before any treatment. Metastases growth rates were calculated and correlated with laboratory and clinical parameters, as well as tumor extent on initial tumor assessment. RESULTS: Twenty-six percent of patients (five of 19) demonstrated no growth over a mean follow-up time of 29 months, 32% (six of 19) had slow growth (1% to 50% increase in volume per month) over a 19-month period, and 42% (eight of 19) had rapid growth (> 50% volume increase per month) over an 11-month period. In patients with rapid growth, 62% died; 0% of the no-growth or slow-growth group died. No clinical or laboratory parameter correlated with growth rate, except the rate increase in fasting serum gastrin and the presence of bilobar liver or bone metastases. The growth rate was highly predictive of death from tumor. CONCLUSION: The growth rate of metastatic gastrinoma varies markedly in different patients and 26% demonstrate no growth. The growth rate needs to considered in the determination of when and in whom antitumor therapy is initiated, as well as in the assessment of response to tumoricidal therapies.

Adult↗

MRI-demonstrable regression of a pituitary mass in a case of primary hypothyroidism after a week of acute thyroid hormone therapy.

Although magnetic resonance imaging (MRI) characteristics of pituitary gland hyperplasia in primary hypothyroidism have been previously described, the time span necessary for the regression of the hyperplasia in response to acute thyroid hormone (TH) therapy has not been defined. A 26-yr-old woman underwent 131I ablation 11 yr before admission. Intermittent poor compliance to levothyroxine (LT4) therapy led to inappropriately high serum thyroid-stimulating hormone (TSH) for her triiodothyronine (T3) and thyroxine (T4) levels. The patient was investigated to rule out TSH-secreting pituitary adenoma or resistance to TH. On admission, the patient's clinical features and thyroid function tests, as well as thyrotropin-releasing hormone (TRH) and acute T3 suppression tests, were in favor of profound primary hypothyroidism. MRI revealed symmetrical enlargement of the pituitary gland with distinct morphological characteristics of a macroadenoma. The patient began high-dose TH therapy and was rescanned six days later. The follow-up scan revealed a dramatic shrinkage of the pituitary gland. Four weeks later, serum T4 and TSH were within the normal range, and repeat MRI scan of the pituitary at that time showed a normal gland. This case is the first to document dramatic shrinkage of pituitary hyperplasia in long-standing primary hypothyroidism within one week of acute TH therapy. MRI alone is unable to reliably differentiate between a TSH-secreting pituitary adenoma and hypothyroidism-induced pituitary hyperplasia. Dynamic endocrine testing as well as repeat pituitary MRI after a brief TH trial may provide a firm diagnosis in similar cases.

Adenoma↗

Primary pigmented nodular adrenocortical disease: reevaluation of a patient with carney complex 27 years after unilateral adrenalectomy.

A 45-yr-old man with primary pigmented nodular adrenocortical disease (PPNAD) is described. This patient underwent unilateral adrenalectomy for ACTH-independent Cushing's syndrome (CS) in 1969. Although his daily urinary free cortisol (UFC) excretion rate normalized, and the major clinical manifestations of CS subsided, loss of a circadian cortisol rhythm persisted after surgery. Twenty-seven years later, the patient presented again with short stature, severe osteopenia, skeletal deformities, thinning of the skin, and myopathy.

Adrenal Cortex Diseases↗

Thyroid gland abnormalities in patients with the syndrome of spotty skin pigmentation, myxomas, endocrine overactivity, and schwannomas (Carney complex)

Carney complex is a multiple neoplasia and lentiginosis syndrome that affects endocrine glands, including the pituitary, adrenals, and testes; thyroid gland involvement has not been unequivocally demonstrated. In the present study, the medical records of 12 families with Carney complex (53 affected patients) were reviewed for evidence of thyroid abnormality; 2 patients with thyroid carcinoma (1 papillary and 1 follicular; 3.8%) and 1 with follicular adenoma were identified in 3 unrelated kindreds. Six affected members of these kindreds were then screened for the presence of thyroid disease (familial cases). We also studied 5 patients with the complex who had no affected relatives (sporadic cases). These 11 patients consisted of 5 adults [mean age, 33.2 +/- 9.2 (+/- SD) yr] and 6 children and adolescents (mean age, 13.8 +/- 2.5 yr). All had normal results of physical and biochemical examination of the thyroid gland (total and free T4, T3, and TSH levels). Thyroid ultrasonography showed hypoechoic, cystic, solid, or mixed lesions in 3 of the 5 adults (60%) and 4 of the 6 children (67%). Two patients underwent fine needle aspiration biopsy, which identified follicular lesions. Thyroid gland abnormalities were documented in 5 siblings and 1 parent-child pair. We conclude that thyroid gland pathology is 1) common in patients with Carney complex; 2) includes a spectrum of abnormalities ranging from follicular hyperplasia and/or cystic changes to carcinoma; and 3) is inherited in an autosomal dominant manner, like the other manifestations of the syndrome, it is therefore, a candidate component of the syndrome. Ultrasonography is useful in the detection and clinical follow-up of these lesions.

Adenoma↗