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PubMed1996

The pituitary V3 vasopressin receptor and the corticotroph phenotype in ectopic ACTH syndrome.

Ectopic ACTH secretion occurs in highly differentiated and rather indolent tumors like bronchial carcinoids or, in contrast, in various types of aggressive and poorly differentiated neuroendocrine tumors. We explored this phenomenon using the recently cloned human pituitary V3 vasopressin receptor as an alternate molecular marker of the corticotroph phenotype. Expression of V3 receptor, corticotrophin releasing hormone (CRH) receptor, and proopiomelanocortin (POMC) genes was examined in tumors of pituitary and nonpituitary origin. A comparative RT-PCR approach revealed signals for both V3 receptor and CHR receptor mRNAs in 17 of 18 ACTH-secreting pituitary adenomas, and 6 of 6 normal pituitaries; in six growth hormone- or prolactin-secreting adenomas, a very faint V3 receptor signal was observed in three cases, and CRH receptor signal was undetected in all. Six of eight bronchial carcinoids responsible for the ectopic ACTH syndrome had both POMC and V3 receptor signals as high as those in ACTH-secreting pituitary adenomas; in contrast, no POMC signal and only a very faint V3 receptor signal were detected in six of eight nonsecreting bronchial carcinoids. Northern blot analysis showed V3 receptor mRNA of identical size in ACTH-secreting bronchial carcinoids and pituitary tumors. Other types of nonpituitary tumors responsible for ectopic ACTH syndrome presented much lower levels of both POMC and V3 receptor gene expression than those found in ACTH-secreting bronchial carcinoids. In contrast with the V3 receptor, CRH receptor mRNA was detected in the majority of neuroendocrine tumors irrespective of their POMC status. These results show that expression of the V3 receptor gene participates in the corticotroph phenotype. Its striking association with ACTH-secreting bronchial carcinoids defines a subset of nonpituitary tumors in which ectopic POMC gene expression is but one aspect of a wider process of corticotroph cell differentiation, and opens new possibilities of pharmacological investigations and even manipulations of this peculiar ACTH hypersecretory syndrome.

ACTH Syndrome, Ectopic↗

PubMed1995

Ectopic ACTH syndrome.

Ectopic ACTH syndrome represents a cancer-induced amplification of a property [proopiomelanocortin (POMC) peptides production] normally present in the cells from which the cancer originated but with aberrant posttranslational processing of POMC resulting in a greatly elevated secretion of ACTH precursors. The classic ectopic ACTH-producing tumors described in the 1960s were highly malignant but more recently slowly growing tumors such as carcinoids are reported with increasing frequency. Clinical features of patients with ectopic ACTH were analyzed, including biochemical abnormalities, plasma ACTH, cortisol and urinary steroids. Dynamic tests such as high-dose dexamethasone suppression, metyrapone and ovine-CRH (oCRH) stimulation were explored, as well as inferior petrosal sinus ACTH sampling before and after oCRH. Among the tumor markers examined, elevation of ACTH precursors was uniformly present followed by increased output of calcitonin, gut hormones, oncofetal and placental hormones in decreasing order. Since more than 90% of ectopic ACTH tumors are neuroendocrine in nature exhibiting APUD characteristics, their 2 markers, neuron-specific enolase and chromogranins are very useful. The imaging procedures for localization of the tumor ranged from chest X-rays to computed tomography and magnetic resonance of the chest and abdomen. Abdominal ultrasonography was also useful. Finally somatostatin receptor scintigraphy permitted demonstration of unrecognized tumors and/or metastases, even when the tumors were occult. The ACTH content, immunostaining for APUD markers and altered POMC processing were evaluated in ectopic tumors and/or metastases. Occult ectopic ACTH syndrome of more than 4-6 months of symptoms without the emergence of an obvious source was reviewed. Since the tumors are often clinically and biochemically undistinguishable from pituitary-dependent Cushing's disease, inferior petrosal sinus sampling for ACTH after oCRH stimulation established the diagnosis in over 90% of the cases. 60% of the occult tumors were thoracic carcinoids (3/4 bronchial carcinoids), followed by small cell lung cancer and pancreatic neuroendocrine tumors. In 12% the primary etiology was not detected. The rare syndrome of ectopic CRH syndrome (6 published cases) leading to excessive stimulation of the pituitary which became hyperplastic and secreted excessive amounts of ACTH is discussed. Finally, the 12 published cases and 1 unreported patient with ectopic CRH-ACTH tumors were reviewed, the majority being metastatic small cell lung carcinomas, bronchial and thymic carcinoids.

Adrenal Glands↗

PubMed1984

Unilateral adrenal hypertrophy in ectopic ACTH syndrome.

Ectopic adrenocorticotropic hormone (ACTH) syndrome was the first ectopic hormone syndrome to be described. It has been shown that most lung tumors have elevated ACTH levels, and most patients with these tumors have high serum ACTH values. The few cases in which cushing's syndrome develops are presumed to have bilateral adrenal hyperplasia. We encountered a case of ectopic ACTH-caused Cushing's syndrome due to unilateral adrenal hypertrophy.

Adrenal Gland Neoplasms↗

PubMed2006

Ectopic ACTH syndrome.

Ectopic adrenocorticotropin secretion (EAS) accounts for 10-15% of cases of Cushing's syndrome and comprises a spectrum of tumours from undetectable isolated lesions to widespread metastatic and aggressive malignancies. EAS is often associated with severe hypercortisolaemia causing hypokalaemia, diabetes, generalized infections, hypertension and psychotic reactions. Surgical resection of the primary lesion, achievable with a curative intent in about 40% of patients with EAS, is associated with complete remission in up to 80% of such cases. It is therefore mandatory to localize the source of ectopic ACTH hypersecretion in order to stage the disease and adopt optimal treatment modalities. Modern cross-sectional imaging techniques can identify the majority of the ACTH secreting lesions, either initially or at follow-up reassessment. However, in approximately 10-20% of patients with EAS, the source of ACTH hypersecretion remains occult in spite of extensive investigation and prolonged followup. In such cases, control of the hypercortisolemia can be achieved with long-term adrenolytic medication. When conditions require a prompt and definitive resolution of the hypercortisolaemia (i.e. as in pregnancy), bilateral adrenalectomy remains an alternative option. This review focuses on the clinical features, diagnostic pitfalls, management and long-term followup of the EAS based on the extensive experience of major referral centres.

ACTH Syndrome, Ectopic↗

PubMed1978

[Differential diagnosis of hypothalamic-hypophyseal Cushing's syndrome and ectopic ACTH syndrome (author's transl)].

Endocrinological symptoms of, on the one hand, hypothalamic-hypophyseal Cushing's syndrome and, on the other, ectopic ACTH syndrome (usually caused by bronchial carcinoma) can often not be distinguished. Reliable differentiation of these two forms of secondary hypercortisolism is necessary, because in hypothalamic-hypophyseal Cushing's syndrome therapy is more and more frequently directed at the anterior pituitary and hypothalamus rather than attempted by bilateral adrenalectomy. The following method was used for distinguishing between the two in six patients: blood was withdrawn by catheter from the jugular vein and the inferior petrosal sinus and the ACTH concentrations measured. Compared with ACTH concentration in a peripheral vein (e.g. cubital vein) that in the jugular vein was higher in five patients by a factor of 1.47 +/- 0.1 and in the inferior petrosal sinus by 2.39 +/- 0.64. A positive diagnosis of hypothalamic-hypophyseal Cushing's syndrome can thus be made. In one patient the diagnosis of ectopic ACTH syndrome could be made from the gradient of ACTH concentration between the cardiac right ventricle and the bronchial artery (1 : 3.75), before there was radiological demonstration of the bronchial carcinoma.

Adrenocorticotropic Hormone↗

PubMed2001

Ectopic ACTH syndrome caused by pulmonary carcinoid tumourlets.

The differential diagnosis of Cushing's syndrome is a major challenge to clinical endocrinologists, especially those infrequent cases referred to as occult ectopic ACTH syndromes. Although bronchial carcinoids are well known to be a cause of Cushing's syndrome due to ectopic ACTH secretion, very few cases of carcinoid tumourlets causing an ACTH ectopic syndrome have been reported, and their origin remains controversial. For some authors, tumourlets and typical carcinoids represent distinct pathological entities, whilst others hold that tumourlets are merely microscopic carcinoid tumours. We report a patient with an aggressive Cushing's syndrome that required bilateral adrenalectomy, diagnosed 22 years before a 3-cm lung nodule became apparent on routine chest X-ray. The biopsy after lung surgery revealed a typical peripheral bronchial carcinoid surrounded by tumourlets. Both tumourlets and carcinoid tumour showed strongly positive ACTH immunostaining. Recently, Arioglu et al. (1998) reported a case of Cushing's syndrome caused by pulmonary carcinoid tumourlets, concluding that this entity should be considered in the differential diagnosis of occult ectopic ACTH syndrome. Furthermore, we consider that the carcinoid tumourlets found in our patient, were the initial source of ACTH, leading to Cushing's syndrome with a rapid onset, and that a loss of cell proliferation control in one of such tumourlets many years later, could have resulted in the development of a typical carcinoid tumour, reinforcing the theory of a common origin of these lesions.

ACTH Syndrome, Ectopic↗

PubMed1994

Ectopic ACTH syndrome and CRH-mediated Cushing's syndrome.

The ectopic ACTH syndrome accounts for a substantial number of patients with naturally occurring Cushing's syndrome. Despite the progress achieved in elucidating the pathophysiology of Cushing's syndrome, clinicians continue to experience diagnostic and therapeutic challenges. This is especially true in those patients presenting with disease mediated by ectopically produced ACTH and CRH. Patients with these disorders may be indistinguishable based on clinical grounds or simple biochemical and radiologic testing from those with Cushing's disease. However, this differentiation is critical because their therapies differ. While clinical researchers continue to develop more effective diagnostic techniques and therapies, further advances in the molecular and cell biology of ACTH and CRH-producing tumors will undoubtedly shed light on the pathogenesis of this perplexing, fascinating and still controversial entity.

ACTH Syndrome, Ectopic↗

PubMed1994

ACTH precursors characterize the ectopic ACTH syndrome.

OBJECTIVE: ACTH is secreted by the pituitary following processing of larger molecular weight precursors, proopiomelanocortin and pro-ACTH. Ectopic ACTH syndrome refers to the secretion of ACTH by non-pituitary tumours, but the predominant circulating form of proopiomelanocortin-related peptides remains unclear. PATIENTS: Fifteen patients with ectopic ACTH syndrome were compared to 20 patients with pituitary-dependent Cushing's syndrome, 22 patients with small cell lung carcinoma but no evidence of Cushing's syndrome, and 25 controls. DESIGN AND MEASUREMENTS: Measurement of plasma ACTH and ACTH precursors using specific monoclonal-based immunoradiometric assays at 0900 h and, in five patients with ectopic ACTH syndrome, at 15-minute intervals for 6-24 hours. RESULTS: ACTH precursors were grossly elevated in patients with ectopic ACTH syndrome (median 2194, range 139-18000 pmol/l) compared to patients with Cushing's disease (median 33, 8-73 pmol/l, P < 0.001), patients with small cell lung carcinomas (38, 8-117 pmol/l, P < 0.001) and controls (26, 10-39 pmol/l, P < 0.001). ACTH levels were also elevated in ectopic ACTH syndrome (0900 h median 34, 11-152 pmol/l) compared to patients with Cushing's disease (0900 h median 8, 3-19 pmol/l), but not to the same degree as ACTH precursors. In contrast with Cushing's disease, ACTH was secreted in a non-pulsatile fashion. ACTH precursors but not ACTH itself correlated with plasma cortisol in patients with ectopic ACTH syndrome (r = 0.65, P < 0.05). Chromatographic analysis of plasma from a patient with ectopic ACTH syndrome confirmed ACTH precursors and not ACTH to be the predominant circulating form. With the cross-reactivity of proopiomelanocortin and pro-ACTH in the ACTH IRMA of < 1 and < 10% respectively, ACTH precursors could represent all the ACTH immunoreactivity in patients with ectopic ACTH syndrome. CONCLUSIONS: Ectopic 'ACTH' is characterized by aberrant processing of proopiomelanocortin and should be more accurately referred to as 'ectopic ACTH precursor syndrome'.

ACTH Syndrome, Ectopic↗

PubMed1994

A case of ectopic ACTH syndrome associated with Zollinger-Ellison syndrome: long-term survival with chemical adrenalectomy.

The female patient in this report was suffering from a pancreatic islet cell tumor which exhibited ectopic ACTH syndrome associated with Zollinger-Ellison syndrome. When this combined syndrome was diagnosed, there were already multiple metastasis to the liver. Zollinger-Ellison syndrome was treated with a histamine-H2-receptor blocker, and ectopic ACTH syndrome was controlled with trilostane, metyrapone and o,p'-DDD. She survived more than 6 years after the diagnosis, mostly as an outpatient. During treatment she became cachexic. After she died, an autopsy was done. Immunohistochemical staining established that tumor cells contained ACTH- and gastrin-like immunoreactivity. Our treatment suggested the efficacy of chemical adrenalectomy in managing ectopic ACTH syndrome associated with Zollinger-Ellison syndrome.

ACTH Syndrome, Ectopic↗

PubMed1992

Mineralocorticoid excess and inhibition of 11 beta-hydroxysteroid dehydrogenase in patients with ectopic ACTH syndrome.

OBJECTIVE: 11 beta-Hydroxysteroid dehydrogenase protects renal mineralocorticoid receptors from cortisol by converting cortisol to inactive cortisone. We hypothesize that 11 beta-dehydrogenase is inhibited by ACTH, providing a mechanism whereby cortisol induces hypokalaemic alkalosis in ectopic ACTH syndrome. DESIGN/MEASUREMENTS: The principal sources of plasma cortisone were assessed by selective venous catheterization with measurement of cortisol and cortisone by radioimmunoassays. The effect of ACTH on peripheral plasma cortisol/cortisone ratio was assessed in healthy volunteers during circadian rhythm, insulin induced hypoglycaemia, and infusions with exogenous ACTH or cortisol. In patients with Cushing's syndrome plasma cortisol/cortisone ratios were related to plasma potassium, corticosterone, and 11-deoxycorticosterone concentrations. PATIENTS: Catheterization was performed in 24 patients with valvular or ischaemic heart disease. Cushing's syndrome patients included: 15 with pituitary adenoma; two with adrenal adenoma; and nine with ectopic ACTH secretion. RESULTS: Plasma cortisol/cortisone ratios were low in renal vein and high in hepatic vein. In healthy volunteers plasma cortisone increased during cortisol infusion but did not change with increases in endogenous or exogenous ACTH. Plasma cortisol/cortisone ratios were higher in ectopic ACTH syndrome than in other forms of Cushing's syndrome. However, the cortisol/cortisone ratio was no better a predictor of hypokalaemia than the levels of 11-deoxycorticosterone or corticosterone. CONCLUSIONS: Peripheral conversion of cortisol to cortisone occurs mainly in the kidney and is inhibited by ACTH. In ectopic ACTH syndrome the characteristic mineralocorticoid excess can be accounted for by a combination of increased secretion of cortisol, corticosterone and of 11-deoxycorticosterone and decreased inactivation of cortisol and corticosterone by 11 beta-dehydrogenase.

11-beta-Hydroxysteroid Dehydrogenases↗

PubMed1979

[Ectopic ACTH syndrome (author's transl)].

Ectopic ACTH syndrome is a clinicopathologic condition produced by certain tumors which release hormone that is indistinguishable from ACTH. It orginates the chemical and clinical anomalies characteristic of Cushing's syndrome by its action on the adrenal glands. The tumors may be present in any organ, though they are most frequently found in the lungs, thymus, pancreas or gastrointestinal tract. They may be benign or malignant, though usually the latter. Secretion of the hormone is completely autnomous; it is release in a way similar to that of the hypophysis. Not infrequently other hormones besides ACTH are also produced, such as MSH, serotonin, and CRF. Ectopic ACTH is of higher molecular weight than hypophyseal ACTH, which suggest it may be comprised of the latter bounded covalently to a peptide. The clinical course is rapid, so that not all of the symptoms of Cushing's syndrome develop. Moon face, osteoporosis, and obesity are typically lacking; melanodermia and hypokalemic alkalosis ofter appear. Laboratory data include an increase in ACTH and cholesterol concentrations, disappearance of the nictameral rhythm, and an increase in urinary excretion of 17-hydroxycorticoids and 17-ketosteroids. Stimulation and supression tests are abnormal. The prognosis is poor and the only possible treatment is a complete surgical removal of the tumor. Irradiation or chemotherapy could be applied as well as the correction of the adrenal hyperfunction by the administration of drugs or by total bilateral adrenalectomy.

Adrenal Glands↗

PubMed2004

[The evaluation of the diagnosis and treatment of 32 cases with ectopic ACTH syndrome].

OBJECTIVE: To investigate and discuss the diagnosis and treatment of ectopic ACTH syndrome. METHODS: Clinical data of 32 cases of ectopic ACTH syndrome, recruited from January 1990 to April 2003 in our hospital, was analyzed. RESULTS: All of the 32 cases presented with clinical and biochemical evidences of Cushing's syndrome. Ten cases were definitively diagnosed as ectopic ACTH syndrome by finding ectopic tumors; 4 cases were highly suspected as ectopic ACTH by blood sampling from femoral vein and infra-petrosal vein and 18 cases were suspected as ectopic ACTH by imaging examinations. Fifteen cases (47%), without identified source of ectopic hormone, were treated with bilateral or unilateral total adrenalectomy, with 1-year survival rate of 60%. Seven cases (22%), with possible source of ectopic hormone, underwent no intervention, with 1-year survival rate of 0. Ten cases underwent radical resection of tumor, 6 of which were bronchial carcinoids and 4 of which were thymic carcinoids, with 1-year survival rate of 60%. CONCLUSION: It is very difficult to localize the tumor of ectopic ACTH syndrome patients. Bilateral adrenalectomy followed by hormonal replacement is effective for most of the patients without identifying source of ectopic hormone.

ACTH Syndrome, Ectopic↗

PubMed2003

Ectopic ACTH syndrome due to thymic atypical carcinoid treated with combination chemotherapy of cisplatin and etoposide.

A 21-year-old woman with Cushing's syndrome presented with a mediastinal tumor. Ectopic ACTH syndrome was diagnosed and the tumor was resected. The histopathological diagnosis was thymic atypical carcinoid. Despite all tumor lesions having been resected, the tumor relapsed and multiple metastatic lesions grew aggressively. Combination chemotherapy with cisplatin and etoposide (VP16) was administered to control tumor progression, and achieved marked therapeutic effects. Maintenance chemotherapy with carboplatin and VP16 achieved long-term tumor control. This case indicates that some patients with atypical carcinoid tumor are good responders to chemotherapy with platinum agents and VP16.

ACTH Syndrome, Ectopic↗

PubMed2006

RT-PCR analysis of corticotroph-associated genes expression in carcinoid tumours in the ectopic-ACTH syndrome.

OBJECTIVE: ACTH is frequently produced in non-pituitary tumours, leading to the ectopic-ACTH syndrome, but the molecular mechanisms of its expression remain obscure. This study was aimed at understanding the transcription mechanisms of the ACTH-precursor gene in carcinoid tumours of the lung or thymus. DESIGN: Transcripts coding for a series of corticotroph-associated transcription factor genes were detected, together with markers of the corticotroph phenotype. We studied a series of 41 carcinoid tumours including 15 with proven ectopic-ACTH syndrome. METHODS: Specific RT-PCR reactions were designed for each gene including alternatively spliced isoforms. RESULTS: The markers of the corticotroph phenotype were detected in all ACTH-positive tumours. Expression of the Tpit and Pitx1 genes were not restricted to ACTH-positive tumours but were also detected in many ACTH-negative carcinoids. Only a subset of ACTH-negative tumours expressed NAK-1/Nur77, and NeuroD1 expression was detected in approximately 50% of the tumours regardless of their secretory status. The glucocorticoid receptor alpha was detected in every tumour in contrast to its beta isoform detectable in a few tumours only. Chicken ovalbumin upstream promoter-transcription factor 1 (COUP-TF1) and peroxisome proliferator-activated receptor (PPAR) gamma2 were expressed in 50% of the tumours of each group whereas PPARgamma1 was expressed in almost every tumour. CONCLUSIONS: ACTH-positive carcinoids do not share a characteristic expression pattern of the corticotroph-associated transcription factor genes, suggesting that the transcriptional mechanisms of the ACTH-precursor gene differ from those in normal pituitary corticotrophs. Expression of Tpit and Pitx1 genes in most carcinoids suggests that some aspects of the pituitary corticotroph phenotype may belong to general carcinoid differentiation.

ACTH Syndrome, Ectopic↗

PubMed1990

A case of small cell carcinoma with ectopic ACTH syndrome.

We report a case of ectopic ACTH syndrome in a 50-year old woman with small cell carcinoma of the lung. Ectopic ACTH syndrome from small cell carcinoma often presents with hypokalemia, metabolic alkalosis and muscle wasting. This patient presented with Cushingnoid features which is unusual in such cases.

ACTH Syndrome, Ectopic↗

PubMed1991

Routine inferior petrosal sinus sampling in the differential diagnosis of adrenocorticotropin (ACTH)-dependent Cushing's syndrome: early recognition of the occult ectopic ACTH syndrome.

The clinical, biochemical, and radiographic features of ectopic ACTH-dependent Cushing's syndrome are often indistinguishable from those of pituitary ACTH-dependent hypercortisolism (Cushing's disease). We prospectively evaluated 29 patients with ACTH-dependent hypercortisolism by means of bilateral inferior petrosal sinus ACTH sampling with ovine CRH (oCRH) stimulation. Patients with Cushing's disease (n = 20), had a maximal basal inferior petrosal sinus to peripheral ACTH ratio (IPS:P-ACTH) of 11.7 +/- 4.4 (+/- SE) from the dominant IPS, which increased to 50.8 +/- 18.3 after oCRH administration. Bilateral IPS sampling was necessary to correctly identify patients with Cushing's disease, since the maximal basal nondominant IPS:P-ACTH was less than 2.0 in over 50% of the patients and remained less than 2.0 after oCRH administration in one third. In contrast, patients with occult ectopic ACTH-secreting neoplasms (n = 9) had maximal basal IPS:P-ACTH of 1.2 +/- 0.1 that did not change after oCRH administration. Occult ectopic ACTH-secreting neoplasms were found in 7 of 9 patients from 0.4-14 yr after the recognition of Cushing's syndrome, and 4 of these patients had intermittent hypercortisolism with prolonged periods of remission. Selective endobronchial lavage for ACTH correctly localized a radiologically occult ACTH-secreting bronchial carcinoid in 1 patient, and magnetic resonance imaging identified a similar neoplasm in a patient with a normal chest computed tomographic scan. Basal ACTH and urinary free cortisol excretion were significantly higher in patients with ectopic ACTH than in those with Cushing's disease, but overlap existed between groups. High dose dexamethasone suppression testing inaccurately classified 24% of patients, and radiological imaging of the pituitary and adrenal glands was misleading. The occult ectopic ACTH syndrome is a common form of ACTH-dependent hypercortisolism that cannot be distinguished from Cushing's disease with routine clinical studies. The accurate differential diagnosis of ACTH-dependent Cushing's syndrome requires bilateral inferior petrosal sinus ACTH sampling with oCRH stimulation.

Adrenocortical Hyperfunction↗

PubMed2005

Malignant gastric carcinoid causing ectopic ACTH syndrome: discrepancy of plasma ACTH levels measured by different immunoradiometric assays.

Discrepancy of plasma ACTH levels measured by different immunoradiometric assays (IRMA) in a case with malignant gastric carcinoid causing ectopic ACTH syndrome was examined by gel chromatography and immunohistochemical analysis. A 49-year-old male was found to have a large gastric tumor, with muscle wasting, hypertension, diabetes and hypokalemia caused by hypercortisolemia. His plasma ACTH levels, although initially elevated, were found to be almost in normal ranges. The discrepancy of plasma ACTH levels was proven to be due to different IRMA kits used; the initial assay was performed by a kit that could recognize high-molecular weight (HMW) form as well as ACTH(1-39), but the later assay by another kit that could recognize only ACTH(1-39). Pathological examination of the gastric tumor was consistent with the diagnosis of malignant carcinoid. Immunohistochemical study revealed that immunoreactivity of proopiomelanocortin (POMC) was positive within the tumor cells, whereas those of ACTH and prohormone convertase 1/3 were negative. Molecular sieving analysis of patient's plasma by gel chromatography coupled with ACTH radioimmunoassay which could recognize HMW form and ACTH(1-39) and two different IRMAs revealed that the predominant form of ACTH was HMW form with a minor peak of ACTH(1-39). This is a rare case of ectopic ACTH syndrome caused by malignant gastric carcinoid with preferential production of HMW form of ACTH, possibly due to unprocessed POMC.

ACTH Syndrome, Ectopic↗

PubMed1988

Episodic ectopic ACTH syndrome associated with pulmonary infarctions.

The etiology of the ectopic ACTH syndrome, associated with certain tumors, is unclear. The ectopic ACTH syndrome was diagnosed in our patient by the characteristic clinical and laboratory findings. Shortly after admission, pulmonary infarctions were documented by lung scans and computed tomography. After treatment with anticoagulants, his plasma ACTH level and its suppressibility became normal. There was no evidence of a tumor. The ectopic ACTH syndrome recurred one year later in conjunction with another episode of pulmonary infarctions. During anticoagulant therapy his infarctions cleared and his plasma ACTH level normalized. In the five years since the onset, no tumor has been found, and plasma ACTH level remains normal and suppressible. We propose that our patient's pulmonary infarctions stimulated pulmonary ACTH production, leading to Cushing's syndrome.

ACTH Syndrome, Ectopic↗