Case report: Ectopic Cushing's syndrome in a young male with hidden lung carcinoid tumor

Ectopic Cushing Syndrome Localized by 68Ga-DOTA-LM3 PET/CT

ABSTRACT

A 53-year-old woman presented with signs of Cushing syndrome with challenges in diagnosis and localization. A novel somatostatin receptor (SSTR)-targeted PET/CT with 68Ga-DOTA-LM3, an SSTR antagonist, revealed a suspicious focal finding in the pancreatic head, proven to be ectopic Cushing syndrome after surgical resection. This interesting image clearly shows the potential of PET imaging with SSTR antagonists as 68Ga-DOTA-LM3 in the diagnosis of ectopic Cushing syndrome.

Drug development and potential targets for Cushing's syndrome

Cushing's syndrome (CS) is a complex disorder characterized by the excessive secretion of cortisol, with Cushing's disease (CD), particularly associated with pituitary tumors, exhibiting heightened morbidity and mortality. Although transsphenoidal pituitary surgery (TSS) stands as the primary treatment for CD, there is a crucial need to optimize patient prognosis. Current medical therapy serves as an adjunctive measure due to its unsatisfactory efficacy and unpredictable side effects. In this comprehensive review, we delve into recent advances in understanding the pathogenesis of CS and explore therapeutic options by conducting a critical analysis of potential drug targets and candidates. Additionally, we provide an overview of the design strategy employed in previously reported candidates, along with a summary of structure-activity relationship (SAR) analyses and their biological efficacy. This review aims to contribute valuable insights to the evolving landscape of CS research, shedding light on potential avenues for therapeutic development.

Median 10 years follow-up of patients with covert Cushing's syndrome: a case series

Background

Ectopic adrenocorticotropic hormone secretion syndrome occurs in 10% of all patients with adrenocorticotropic-hormone-dependent hypercortisolism. It is usually associated with overt malignancies or with occult and indolent tumors. This study aims to confirm the source of ectopic adrenocorticotropic hormone in four patients with ectopic Cushing’s syndrome over time.

Case presentation

A 38-year-old Iranian man with Cushing’s syndrome underwent bilateral adrenalectomy since the source of ectopic adrenocorticotropic hormone secretion was not localized and pituitary imaging was normal. A whole-body scan revealed a right-lung tumoral mass with mediastinal lymph node metastasis. The mass was assumed a lung carcinoid tumor with mediastinal adenopathy. Right-lung mid-zone lobectomy and mediastinal lymphadenectomy were done. In a 47-year-old Iranian man with Cushing’s syndrome, whole-body computed tomography scan revealed a pulmonary nodule in the posterior segment of the left lower lobe of the lung. The third case was a 25-year-old Iranian man who presented with symptoms and signs of Cushing’s syndrome. Pituitary magnetic resonance imaging revealed a microadenoma 5 × 9 mm. Whole-body scan showed abnormal focal somatostatin receptors analog avid lesion in the posterior aspect of inferior third of right lung, highly suggestive of ectopic adrenocorticotropic-hormone-producing tumor. The last case was a 43-year-old Iranian woman with Marfan syndrome with a history of mitral and aortic valve replacement and chronic dissection of the aorta, who presented with symptoms and signs of Cushing’s syndrome. She underwent bilateral adrenalectomy 1 year later owing to failure to locate ectopic adrenocorticotropic hormone syndrome. Whole-body scan showed abnormally increased radiotracer uptake in the midline of the skull base and posterior aspect of the middle zone of left hemithorax and bed of left lobe of thyroid.

Conclusion

The clinical spectrum of ectopic adrenocorticotropic hormone secretion syndrome is wide, and distinguishing Cushing’s disease from ectopic adrenocorticotropic hormone secretion syndrome is difficult. Initial failure to identify a tumor is common. Pulmonary carcinoid or occult source of ectopic adrenocorticotropic hormone secretion syndrome is usually the cause. In occult cases of ectopic adrenocorticotropic hormone in which the tumor cannot be localized, serial follow-up with serial computed tomography, magnetic resonance imaging, or scintigraphy is recommended for several years until the tumor can be localized and treated.

Experience of Ectopic Adrenocorticotropin Syndrome: 88 Cases With Identified Causes

OBJECTIVE

Ectopic adrenocorticotropic hormone syndrome (EAS) is a rare cause of Cushing's syndrome and diagnosis and management remain challenging. The aim of this study was to present the clinical spectrum of a group of EAS cases in a single center to explore better management strategies.

METHODS

A retrospective study was conducted to identify 88 confirmed EAS cases at our hospital from 1984 to 2019. The clinical, biochemical, imaging, and pathological features were analyzed.

RESULTS

Of the 88 eligible patients with EAS, 38 (43.2%) cases of pulmonary neuroendocrine tumors (NETs) and a larger number of thymic/mediastinal NETs (29 cases, 33%) were identified. The clinical and biological features of EAS and Cushing's disease overlapped but were more severe in EAS. Inferior petrosal sinus sampling (97.4%) and computed tomography (85.4%) provided the highest positive diagnostic accuracy. Computed tomography is also a useful tool to identify tumors in chest cavity compared with nonchest lesions (91.2% vs 57.1%). Although a greater tumor size (4.54 cm vs 1.44 cm) and higher rate of insuppressible high-dose dexamethasone suppression test (83.3% vs 51.5%) were found in thymic/mediastinum NETs than in pulmonary NETs, the level of hormone production had no difference.

CONCLUSION

EAS had more common and severe clinical presentations than Cushing's disease, and multiple imaging approaches are required for reliable diagnosis. A higher proportion of thymic/mediastinal NETs was found in our study. For patients without a certain tumor source, long-term follow-up and further evaluations are needed.

Recurrence of Ectopic Cushing’s Syndrome 10 Years After Bilateral Adrenalectomy

Ectopic Cushing’s syndrome is a severe form of Cushing disease. Treatment usually involves the resection of the adrenocorticotropic hormone producing tumor. In certain cases, bilateral adrenalectomy is carried out as a final resort in treatment. We present a patient who had a lung carcinoid tumor, which was producing adrenocorticotropic hormone and causing ectopic Cushing’s syndrome. Lung wedge resection failed to normalize cortisol level, and he had bilateral adrenalectomy. Ten years later, he had a recurrence of Cushing’s disease due to lymph node metastasis of his carcinoid tumor.

Ectopic ACTH syndrome of different origin-Diagnostic approach and clinical outcome. Experience of one Clinical Centre

PURPOSE

Ectopic Cushing Syndrome (EAS) is a rare condition responsible for about 5-20% of all Cushing syndrome cases. It increases the mortality of affected patients thus finding and removal of the ACTH-producing source allows for curing or reduction of symptoms and serum cortisol levels. The aim of this study is to present a 20-year experience in the diagnosis and clinical course of patients with EAS in a single Clinical Centre in Southern Poland as well as a comparison of clinical course and outcomes depending on the source of ectopic ACTH production-especially neuroendocrine tumors with other neoplasms.

METHODS

Twenty-four patients were involved in the clinical study with EAS diagnosed at the Department of Endocrinology between years 2000 and 2018. The diagnosis of EAS was based on the clinical presentation, hypercortisolemia with high ACTH levels, high dose dexamethasone suppression test and/or corticotropin-releasing hormone tests. To find the source of ACTH various imaging studies were performed.

RESULTS

Half of the patients were diagnosed with neuroendocrine tumors, whereby muscle weakness was the leading symptom. Typical cushingoid appearance was seen in merely a few patients, and weight loss was more common than weight gain. Patients with neuroendocrine tumors had significantly higher midnight cortisol levels than the rest of the group. Among patients with infections, we observed a significantly higher concentrations of cortisol 2400 levels in gastroenteropancreatic neuroendocrine tumors. Chromogranin A correlated significantly with potassium in patients with neuroendocrine tumors and there was a significant correlation between ACTH level and severity of hypokalemia.

CONCLUSION

EAS is not common, but if it occurs it increases the mortality of patients; therefore, it should be taken into consideration in the case of coexistence of severe hypokalemia with hypertension and muscle weakness, especially when weight loss occurs. Because the diagnosis of gastroenteropancreatic neuroendocrine tumor worsens the prognosis-special attention should be paid to these patients.

Case-series of paraneoplastic Cushing syndrome in small-cell lung cancer

The objective of this study is to report three cases of paraneoplastic or ectopic Cushing syndrome, which is a rare phenomenon of the adrenocorticotropic hormone (ACTH)-dependent Cushing syndrome. Three cases are reported in respect of clinical presentation, diagnosis and treatment in addition to relevant literature review. The results showed that ectopic ACTH secretion can be associated with different types of neoplasm most common of which are bronchial carcinoid tumors, which are slow-growing, well-differentiated neoplasms with a favorable prognosis and small-cell lung cancer, which are poorly differentiated tumors with a poor outcome. The latter is present in two out of three cases and in the remaining one, primary tumor could not be localized, representing a small fraction of patients with paraneoplastic Cushing. Diagnosis is established in the setting of high clinical suspicion by documenting an elevated cortisol level, ACTH and doing dexamethasone suppression test. Treatment options include management of the primary tumor by surgery and chemotherapy and treating Cushing syndrome. Prognosis is poor in SCLC. We concluded that in front of a high clinical suspicion, ectopic Cushing syndrome diagnosis should be considered, and identification of the primary tumor is essential.