Ectopic Cushing and other paraneoplastic syndromes in thoracic neuroendocrine tumors

Ectopic Cushing syndrome in Colombia

OBJECTIVE

The aim was to describe the clinical features of patients with ectopic Cushing syndrome (ECS) from Colombia and compare these findings with other series to provide the best management for these patients.

METHODS

Records of patients with ECS from 1986 to 2017 were retrospectively reviewed; patients with a diagnosis of adrenal or pituitary Cushing syndrome (CS) were excluded.

RESULTS

Fourteen patients with ECS were analyzed in this study. The mean age was 54.4 (SD 17.1) years, and the female to male ratio was 1.33:1. Regarding the etiology of ECS, four patients had lung carcinoids (28.6%), three had small-cell lung carcinoma (21.4%), three had pancreatic neuroendocrine tumors (21.4%), one had medullary thyroid cancer (7.1%), one had non-metastatic pheochromocytoma (7.1%), one had metastatic thymoma (7.1%) and one patient had an occult source of ACTH (7.1%). The most common clinical features at presentation were moon-face, muscle weakness, diabetes mellitus and hypertension. Hyperpigmentation was present in 36% of patients, and 12 patients had hypokalemia with a mean value of 2.3 mEq/L (SD 0.71). The median basal cortisol, 24-hour urinary free cortisol (UFC) and ACTH were 30.5 ug/dL (IQR 21-59 ug/dL), 2,600 ug/24 h (IQR 253-6,487 ug/24 h) and 91 pg/mL (IQR 31.9-141.9), respectively. Thirteen patients (92.8%) had the site of the primary lesion identified. Six patients had undergone a surgical intervention to address the primary tumor. Resection was curative in 28.5% of patients. Death occurred in 57.1% of patients, and the median overall survival was 27 months. Intrathoracic tumors had the most aggressive behavior.

CONCLUSION

ECS is a rare disease; however, it is associated with high morbidity and mortality. A rapid intervention supported by an interdisciplinary group is required to improve overall survival and quality of life.

A rare case of ectopic ACTH syndrome with rhabdomyolysis

BACKGROUND

Manifestations of hypokalaemia in ectopic adrenocorticotropic hormonesyndrome(EAS) vary from mild muscle weakness to life-threatening arrhythmia. Herein, we present a rare case of EAS with concomitant rhabdomyolysis(RM) as a result of intractable hypokalaemia.

CASE PRESENTATION

A 64-year-old man was admitted for limb weakness and facial hyperpigmentation for 2 weeks. Lab tests revealed intractable hypokalaemia (lowest at 1.8 mmol/L) and metabolic alkalosis. The diagnosis of RM was based on a creatine kinase(CK)level of 5 times the upper limit. The elevated CK and myohemoglobin (Mb) levels returned to within the normal range after the alleviation of hypokalaemia. The patient was diagnosed with ACTH-dependent Cushing's syndrome (CS) based on unsuppressed serum cortisol after a low-dose dexamethasone suppression test(LDDST) and remarkably elevated ACTH levels. The diagnosis of EAS was made based on the results of a high-dose dexamethasone suppression test(HDDST) and bilateral inferior petrosal sinus sampling(BIPSS). Multiple lymph nodes in the left supraclavicular fossa, right root of neck, mediastinum and bilateral hili of the lung were found with abnormal uptake of ⁶⁸Ga-DOTA-NOC. Mediastinoscopic lymph node biopsy was performed. The pathological diagnosis was small-cell and large-cell neuroendocrine carcinoma with positive ACTH staining. The patient was prescribed mifepristone and received one cycle of chemotherapy. The patient could not tolerate subsequent chemotherapy and died of dyscrasia.

CONCLUSIONS

RM is a rare complication of EAS with insidious onset and atypical clinical manifestations. Serum potassium levels should be vigilantly monitored to avoid RM in EAS.

Ectopic ACTH production by thymic and appendiceal neuroendocrine tumors - two case reports

OBJECTIVES

Ectopic adrenocorticotropic syndrome (EAS) causes approximately 10-18% of cases of Cushing's syndrome (CS) in adults, while in children it occurs much less frequently.

CASE PRESENTATION

We report two cases of neuroendocrine tumors (of the thymus and the appendix) in a 12-year-old boy and a 15-year-old girl who presented with the clinical features of CS. Elevated serum cortisol, ACTH, and chromogranin levels were observed in both patients. Diagnoses were made on the basis of a mass in the thymus/appendix region visualized with chest/abdominal CT scan and radiotracer accumulation in scintigraphy in the same areas. Histopathological examinations confirmed the diagnoses of NET.

CONCLUSION

EAS is an extremely rare endocrine disorder. However, it should be taken into consideration in the diagnostic process of every case of ACTH-dependent CS.

Ectopic ACTH Secretion in a Child With Metastatic Ewing's Sarcoma: A Case Report

Ectopic ACTH syndrome is rare in pediatric age. Sarcomas that cause Ectopic ACTH Syndrome (EAS) are even more uncommon. Currently, only three cases of EAS caused by Ewing' sarcoma have been reported. We detail a 10-year-old boy with Cushing's syndrome symptoms caused by ectopic ACTH production by a metastatic Ewing's sarcoma of the right ischio-pubic and ileo-pubic branches. The rapid appearance of cushingoid symptoms, with significant weight gain, acne, hirsutism, and hypercortisolism were implications of ectopic ACTH production as paraneoplastic Cushing's Syndrome. The very high levels of ACTH and non-suppression at the high dose dexamethasone test confirmed the clinical suspicion. We underline the possibility EAS was caused by an ACTH-secreting tumor, including soft tissue sarcomas.

Two types of ectopic Cushing syndrome or a continuum? Review

BACKGROUND

Two types of ectopic Cushing syndrome (ECS) are described: ECS associated with aggressive neoplasms, and ECS with indolent and occult tumors, however, there is a lack of studies that thoroughly review their characteristics.

METHODS

A systematic review was carried out on PUBMED of all the papers about the ECS, in order to better define the types of this subcategory of Cushing's syndrome, highlighting the differential aspects between these subgroups.

RESULTS

It was found that in 50% of cases the prototypic "aggressive" ECS is caused by small cell lung carcinomas (SCLC). In these cases, the clinical presentation may be atypical, predominating the signs and symptoms derived from the protein catabolism. Cortisol and ACTH levels are extremely high, the clinical presentation is abrupt (< 3-6 months) and the tumor is usually advanced, being impossible a curative treatment. On the other hand, "indolent" ECS is mainly represented by carcinoid tumors (CT). In these cases the clinical presentation overlaps enormously with that of Cushing's disease (CD). Cortisol and ACTH levels are slightly elevated, the clinical presentation is progressive (> 6 months) and the prognosis is usually good, and a curative treatment is possible in about 75% of the cases.

CONCLUSION

Although there is no absolute differentiation between the two extremes of ECS, a classification could be established in two groups, guided by its clinical and biochemical characteristics, and mainly by the type and stage of the ACTH-secreting tumor. However, a small percentage of tumors do not fit in this simple grouping, and may present both phenotypes or an intermediate one.

Ectopic Cushing's syndrome due to adrenocorticotropic hormone secreting atypical thymic carcinoid tumor

Cushing’s syndromes (CS) due to thymic carcinoids are rarely seen. In this text, a case with CS due to ectopic adrenocorticotropic hormone (ACTH) secreting atypical thymic carcinoid tumor is presented. A 50-year-old Turkish male patient was admitted to our emergency department with typical CS features. Basal hormone profile, low- and high-dose dexamethasone suppression tests, and inferior petrosal sinus sampling results were consistent with ectopic ACTH secretion. Thorax computerized tomography showed an upper mediastinal mass, and trans-thoracic biopsy showed atypical thymic carcinoid with positive ACTH staining. Since the vascular invasion was detected, tumor was accepted inoperable; somatostatine receptor analogs, chemotherapy, and radiotherapy were planned. Ectopic CS can be derived from atypical thymic carcinoid. In this case, ACTH staining was used to confirm ACTH secretion from thymic tissue, and positive staining was detected. ACTH staining routinely was not performed for extra hypophyseal tissue tumors. In suspicious and difficult cases, ACTH staining can be helpful to confirm the presence of ACTH in tumor tissues.

Ectopic Cushing syndrome: Report of 9 cases

INTRODUCTION

Ectopic Cushing's syndrome (ECS) is a rare condition caused by ACTH secretion by extrapituitary tumors. Its low frequency makes it difficult to acquire experience in its management. The aim of this study was to describe patients with ECS seen at the endocrinology department of a tertiary hospital over 15 years.

METHODS

This was a retrospective study of the clinical, biochemical and radiographic data, treatment, and course of patients with ECS seen from 2000 to 2015.

RESULTS

Nine patients (6 of them female) with a mean age of 47 years were included in the study. The clinical syndrome developed in less than 3 months in all cases but one, and most patients also had edema, hyperpigmentation and/or hypokalemia. Mean urinary free cortisol and ACTH levels were 2,840μg/24h and 204pg/mL respectively. The ectopic origin was confirmed by a combination of dynamic non-invasive tests and radiographic studies in most cases. The tumor responsible could be identified in 8 cases, and 7 patients had metastatic dissemination. Primary treatment was surgery in one patient, surgery combined with systemic therapy in 3, and chemotherapy in the other 3 patients. Bilateral adrenalectomy was required in 4 patients to control hypercortisolism. After a mean follow-up of 40 months, 3 patients died, 5 were still alive, and one had been lost to follow-up.

CONCLUSIONS

Our study confirms that ECS covers a wide spectrum of tumors of different aggressiveness and nature. The ectopic origin of Cushing's syndrome can usually, be suspected and confirmed in most cases without the need for invasive tests. Control of both hypercortisolism and the tumor requires multiple treatment modalities, and multidisciplinary management is recommended.

PET imaging in ectopic Cushing syndrome: a systematic review

Cushing syndrome due to endogenous hypercortisolism may cause significant morbidity and mortality. The source of excess cortisol may be adrenal, pituitary, or ectopic. Ectopic Cushing syndrome is sometimes difficult to localize on conventional imaging like CT and MRI. After performing a multilevel thoracoabdominal imaging with CT, the evidence regarding the use of radiotracers for PET imaging is unclear due to significant molecular and etiological heterogeneity of potential causes of ectopic Cushing's syndrome. In our systematic review of literature, it appears that GalLium-based (Ga68) somatostatin receptor analogs have better sensitivity in diagnosis of bronchial carcinoids causing Cushing syndrome and FDG PET appears superior for small-cell lung cancers and other aggressive tumors. Further large-scale studies are needed to identify the best PET tracer for this condition.