Hypokalemia, metabolic alkalosis, and hypertension: Cushing's syndrome in a patient with metastatic prostate adenocarcinoma

ACTH-secreting metastatic prostate cancer with neuroendocrine differentiation

Cushing's syndrome (CS) due to ectopic adrenocorticotropic hormone (ACTH) secretion (EAS) can result from a variety of tumours and rarely from those of prostatic origin. We present a male patient in his early 60s with ACTH-secreting metastatic prostate adenocarcinoma with neuroendocrine differentiation (ICD-O code 8574/3) years after prostatectomy and androgen-deprivation therapy, initially presenting with Cushingoid features. After open radical prostatectomy and bilateral orchiectomy for disease recurrence, the patient was found to have metastatic liver and bone lesions highly suggestive of metastatic prostatic cancer. About 10% of cells on liver biopsy expressed ACTH, a finding consistent with EAS as the cause of CS. His stay was complicated with multiple infections and ultimate death. Hence, we report a case of metastatic prostate adenocarcinoma with neuroendocrine differentiation who presented with CS. We also emphasize the importance of adequate and timely treatment.

ECTOPIC ADRENOCORTICOTROPIC HORMONE SYNDROME DUE TO METASTATIC PROSTATE CANCER WITH NEUROENDOCRINE DIFFERENTIATION

Objective

Neuroendocrine differentiation of prostate cancer can result in ectopic adrenocorticotropic hormone (ACTH) secretion (EAS) and Cushing syndrome. The aim of this report is to highlight this unusual mechanism of hypercortisolism and its management.

Methods

We report a 73-year-old patient with a history of prostate adenocarcinoma who presented with severe weakness, hyperglycemia, and hypokalemia caused by EAS.

Results

Diagnostic workup showed elevated 24-hour urine cortisol and ACTH levels consistent with EAS. Fluorodeoxyglucose positron emission tomography-computed tomography revealed a hypermetabolic mass in the prostate and metastatic lesions to the liver and bones. Liver biopsy was consistent with small cell carcinoma with positive immunostaining for ACTH. Pleural fluid analysis was consistent with high-grade neuroendocrine carcinoma. The patient underwent chemotherapy with carboplatin and etoposide. Hypercortisolism was treated with ketoconazole, metyrapone, mifepristone, and spironolactone. He suffered complications including opportunistic infections, deep venous thrombosis, and delirium. Given his poor prognosis and clinical decline, the patient opted for comfort measures only in a hospice facility.

Conclusion

Treatment-related neuroendocrine differentiation of prostate cancer is an emerging entity that may be associated with paraneoplastic syndromes including EAS.

Ectopic cushing's syndrome due to corticotropin releasing hormone

Cushing's syndrome (CS) secondary to corticotropin releasing hormone (CRH) producing tumors is rare. In this paper we present an Iranian patient who was admitted to our hospital with classic signs and symptoms of CS. Laboratory evaluation revealed high serum and urine cortisol which could not be suppressed with dexamethasone. Abdominal CT scan revealed a mass in abdominal cavity. A percutaneous needle biopsy was performed and histopathologic evaluation revealed that the mass was a neuroendocrine tumor. A multi-disciplinary approach including resection of the mass, bilateral adrenalectomy somatostatin analogue and chemotherapy was applied for management of the disease. Extensive review of English literature focusing on the topic from 1971 to 2018 revealed that there have been only 75 similar cases. Clinical, laboratory, imaging, histopathologic characteristics and managements of these patients will also be discussed in this paper.

Molecular analysis and literature-based hypothesis of an immunonegative prostate small cell carcinoma causing ectopic ACTH syndrome

Ectopic ACTH syndrome (EAS) due to a prostate small cell carcinoma (SCC) is very rare with only 26 cases reported to date and has a poor prognosis. We here describe another case of this disorder that was clinically typical based on prior reports as it showed hypercortisolemia and severe hypokalemia with multiple metastasis. However, our current case of prostate SCC causing EAS is the first to display negative immunostaining for ACTH despite detectable POMC mRNA expression in the primary lesion. ACTH immunonegativity is thought to be associated with a more aggressive disease course and a poorer prognosis although there are few studies of the underlying mechanisms. We explored two possibilities for this finding in our current patient: aberrant POMC processing prevented immunodetection with an anti-ACTH antibody; and the ACTH content per cell was below the threshold for immunodetection due to its rapid secretion or low synthesis. The aberrant processing theory was thought to be less likely because of immunonegative findings even using anti-POMC/ACTH antibodies. As the plasma ACTH levels in our patient were comparable with those reported for previous immunopositive prostate EAS cases, we speculated that the depletion of ACTH may be caused not only by rapid secretion but also by low production levels as a sign of de-differentiation. De-differentiation may therefore explain the mechanism underlying the negative correlation between immunoreactivity for ACTH in EAS and disease aggressiveness. We believe that our present findings will be of use in future prospective studies aimed at confirming the mechanism of immunonegativity.

Dual Paraneoplastic Endocrine Syndromes Heralding Onset of Extrapulmonary Small Cell Carcinoma: A Case Report and Narrative Review

OBJECTIVE

Extrapulmonary small cell carcinoma (EPSCC) is rare and frequent metastases at presentation can complicate efforts to identify a site of origin. In particular, SCC comprises <1% of prostate cancers and has been implicated in castration resistance.

METHODS

Clinical, laboratory, imaging, and pathology data are presented.

RESULTS

A 56-year-old man with locally advanced prostate adenocarcinoma on androgen deprivation therapy presented with a clogged nephrostomy tube. Laboratory results included calcium 13.8 mg/dL (8.5-10.5 mg/dL), albumin 3.6 g/dL (3.5-5 mg/dL), and potassium 2.8 mmol/L (3.5-5.2 mmol/L). Hypercalcemia investigation revealed intact PTH 19 pg/mL (16-87 pg/mL), 25-OH vitamin D 15.7 ng/mL (>30 ng/mL), and PTH-related peptide (PTHrP) 63.4 pmol/L (<2.3 pmol/L). Workup for hypokalemia yielded aldosterone 5.3 ng/dL (<31 ng/dL), renin 0.6 ng/mL/h (0.5-4 ng/mL/h), and 6:00 a.m. cortisol 82 µg/dL (6.7-22.6 µg/dL) with ACTH 147 pg/mL (no ref. range). High-dose Dexamethasone suppression testing suggested ACTH-dependent ectopic hypercortisolism. Contrast-enhanced CT findings included masses in the liver and right renal pelvis, a heterogeneous enlarged mass in the region of the prostate invading the bladder, bilateral adrenal thickening, and lytic lesions in the pelvis and spine. Liver biopsy identified epithelioid malignancy with Ki proliferation index 98% and immunohistochemical staining positive for synaptophysin and neuron-specific enolase, compatible with high-grade small cell carcinoma. Staining for ACTH was negative; no stain for CRH was available. Two weeks after chemotherapy, 6:00 a.m. cortisol normalized and CT scans showed universal improvement.

CONCLUSION

Extensive literature details paraneoplastic syndromes associated with SCC, but we report the first case of EPSCC diagnosed due to onset of dual paraneoplastic syndromes.

Severe Cushing's syndrome due to small cell prostate carcinoma: a case and review of literature

Cushing's syndrome (CS) due to ectopic adrenocorticotrophic hormone (ACTH) is associated with a variety of tumours most of which arise in the thorax or abdomen. Prostate carcinoma is a rare but important cause of rapidly progressive CS. To report a case of severe CS due to ACTH production from prostate neuroendocrine carcinoma and summarise previous published cases. A 71-year-old male presented with profound hypokalaemia, oedema and new onset hypertension. The patient reported two weeks of weight gain, muscle weakness, labile mood and insomnia. CS due to ectopic ACTH production was confirmed with failure to suppress cortisol levels following low- and high-dose dexamethasone suppression tests in the presence of a markedly elevated ACTH and a normal pituitary MRI. Computed tomography demonstrated an enlarged prostate with features of malignancy, confirmed by MRI. Subsequent prostatic biopsy confirmed neuroendocrine carcinoma of small cell type and conventional adenocarcinoma of the prostate. Adrenal steroidogenesis blockade was commenced using ketoconazole and metyrapone. Complete biochemical control of CS and evidence of disease regression on imaging occurred after four cycles of chemotherapy with carboplatin and etoposide. By the sixth cycle, the patient demonstrated radiological progression followed by recurrence of CS and died nine months after initial presentation. Prostate neuroendocrine carcinoma is a rare cause of CS that can be rapidly fatal, and early aggressive treatment of the CS is important. In CS where the cause of EAS is unable to be identified, a pelvic source should be considered and imaging of the pelvis carefully reviewed.

En Bloc Resection of Solitary Functional Secreting Spinal Metastasis

Study Design Literature review. Objective Functional secretory tumors metastatic to the spine can secrete hormones, growth factors, peptides, and/or molecules into the systemic circulation that cause distinct syndromes, clinically symptomatic effects, and/or additional morbidity and mortality. En bloc resection has a limited role in metastatic spine disease due to the current paradigm that systemic burden usually determines morbidity and mortality. Our objective is to review the literature for studies focused on en bloc resection of functionally active spinal metastasis as the primary indication. Methods A review of the PubMed literature was performed to identify studies focused on functional secreting metastatic tumors to the spinal column. We identified five cases of patients undergoing en bloc resection of spinal metastases from functional secreting tumors. Results The primary histologies of these spinal metastases were pheochromocytoma, carcinoid tumor, choriocarcinoma, and a fibroblast growth factor 23-secreting phosphaturic mesenchymal tumor. Although studies of en bloc resection for these rare tumor subtypes are confined to case reports, this surgical treatment option resulted in metabolic cures and decreased clinical symptoms postoperatively for patients diagnosed with solitary functional secretory spinal metastasis. Conclusion Although the ability to formulate comprehensive conclusions is limited, case reports demonstrate that en bloc resection may be considered as a potential surgical option for the treatment of patients diagnosed with solitary functional secretory spinal metastatic tumors. Future prospective investigations into clinical outcomes should be conducted comparing intralesional resection and en bloc resection for patients diagnosed with solitary functional secretory spinal metastasis.

Undetected hypoparathyroidism: An unusual cause of perioperative morbidity

Routine investigation of serum calcium is not recommended in ASA one and two patients unless abnormalities of calcium metabolism are clinically suspected. The clinical features of hypocalcaemia can often be subtle and may manifest in the presence of associated factors. Hypoparathyroidism, an important cause of hypocalcaemia, often presents as soft tissue calcification (ostosis). Ligamentum flavum ostosis can present with compressive myelopathy requiring laminectomy. We report a case of ligamentum flavum ostosis and subclinical hypocalcaemia due to hypoparathyroidism, who went undetected pre-operatively resulting in significant post-operative morbidity.

Corticotropin-releasing hormone receptors mediate apoptosis via cytosolic calcium-dependent phospholipase A₂ and migration in prostate cancer cell RM-1

Peripheral corticotropin-releasing hormone receptors (CRHRs) are G protein-coupled receptors that play different roles depending on tissue types. Previously, we discovered the mechanism of CRHR-mediated apoptosis of mouse prostate cancer cell line (RM-1) to be a change of Bcl-2:Bax ratio, and CRH was found to inhibit transforming growth factor β migration of breast cancer cells via CRHRs. In the present study, we investigated cytosolic calcium-dependent phospholipase A2 (cPLA2) bridging CRHR activations and Bcl-2:Bax ratio and the effect of CRHR activation on cell migration. Silencing of cPLA2 attenuated a CRHR1 agonist, CRH-induced apoptosis, and the decrease of the Bcl-2:Bax ratio, whereas silencing of cPLA2 aggravated CRHR2 agonist, Urocortin 2 (Ucn2)-inhibited apoptosis, and the increase of the Bcl-2:Bax ratio. CRH in a time- and concentration-dependent manner increased cPLA2 expression mainly through interleukin 1β (IL1β) upregulation. Ucn2 decreased cPLA2 expression through neither tumor necrosis factor α nor IL1β. CRH-suppressed decay of cPLA2 mRNA and Ucn2 merely suppressed its production. Overexpression of CRHR1 or CRHR2 in HEK293 cells correspondingly upregulated or downregulated cPLA2 expression after CRH or Ucn2 stimulation respectively. In addition, both CRH and Ucn2 induced migration of RM-1 cells. Our observation not only established a relationship between CRHRs and cell migration but also for the first time, to our knowledge, demonstrated that cPLA2 participates in CRHR1-induced apoptosis and CRHR2-inhibited apoptosis.

Metastatic esthesioneuroblastoma secreting adrenocorticotropic hormone in pediatric patients

The purpose of this article was to report a pediatric case of secondary cervical esthesioneuroblastoma involving the parapharyngeal lymph nodes. A 3-year-old boy came to our clinical observation because of a right lymphonodal mass evidenced by nuclear magnetic resonance and a diagnosis of Cushing syndrome associated with ectopic adrenocorticotropic hormone secretion, moon face, central obesity, asthenia, and hirsutism. At the age of 10 months, the patient underwent endoscopic surgery for asportation of the World Health Organization stage IV esthesioneuroblastoma. At 38 months of age, the patient underwent right parapharyngeal lymphadenectomy with surgical access by a double mandibulectomy. After surgery, serum ACTH, cortisolemia, and urinary excretion of cortisol were within the reference range. Blood pressure was recorded at 110/70 mm Hg. Moon face disappeared, as well as central obesity and hirsutism. Clinical report is presented together with brief review of literature.

Unusual cause of ectopic secretion of adrenocorticotropic hormone: Cushing syndrome attributable to small cell prostate cancer

OBJECTIVE

To report a rare cause of ectopic adrenocorticotropic hormone (ACTH) secretion leading to severe Cushing syndrome.

METHODS

We describe the clinical presentation and management of a case of Cushing syndrome attributable to ectopic ACTH secretion from small cell cancer of the prostate.

RESULTS

In a 70-year-old man with hypertension and diabetes, congestive heart failure developed. He was found to have severe hypokalemia (serum potassium, 1.7 mEq/L) and a huge pelvic mass on a computed tomographic scan performed because of a complaint of urinary retention. Transurethral biopsy of the prostate showed features of small cell prostate cancer. Hormonal evaluation revealed a high urine free cortisol excretion of 6,214.5 microg/d (reference range, 36 to 137), confirming the diagnosis of Cushing syndrome. A serum ACTH level was elevated at 316 ng/dL (reference range, 10 to 52). An overnight high-dose (8 mg orally) dexamethasone suppression test was positive (serum cortisol levels were 43.2 and 41 microg/dL before and after suppression, respectively), and magnetic resonance imaging of the pituitary gland disclosed no abnormalities. A prostate biopsy specimen showed small cell prostate cancer with positive staining for ACTH. The tumor was found to be unresectable, and the poor condition of the patient did not allow for bilateral adrenalectomy. He was treated with ketoconazole and metyrapone, which yielded good temporary control of his Cushing syndrome (24-hour urine free cortisol decreased to 55.2 microg/d). He received 1 cycle of chemotherapy (etoposide and cisplatin), but he died 6 months later as a result of sepsis.

CONCLUSION

Small cell prostate cancer is a rare subtype that can be associated with ectopic secretion of ACTH and severe Cushing syndrome. With this subtype of prostate cancer, Cushing syndrome should be considered and appropriately managed.

Cushing's syndrome due to ectopic ACTH production by (neuroendocrine) prostate carcinoma

Ectopic adrenocorticotropin (ACTH) secretion accounts for less than 10% of all causes of endogenous Cushing's syndrome (CS) and is usually associated with neuroendocrine tumors and small cell carcinoma of the lung. We report the case of a 62-year-old man with CS due to ectopic ACTH production by small cell carcinoma of the prostate. He presented with severe hypercortisolism and associated symptoms. Plasma neuron specific enolase (NSE) was grossly elevated. Despite performing a laparoscopic bilateral adrenalectomy, the patient died as a result of sepsis with multi-organ failure. Post-mortem immunohistochemical staining of prostate tumor tissue showed ACTH expression. ACTH staining was also performed in four additional patients with small cell carcinoma of the urinary tract without CS. None of these additional cases showed a positive staining for ACTH. Although a rare cause of ectopic ACTH production, neuroendocrine prostate carcinoma should be considered in male patients with Cushing's syndrome, in particular in those with an occult source of ACTH overproduction.

Two cases of ectopic adrenocorticotropic hormone syndrome with olfactory neuroblastoma and literature review

Olfactory neuroblastomas are rare, slow-growing malignant tumors, usually diagnosed at advanced stages. Ectopic adrenocorticotropic hormone (ACTH) syndrome caused by an olfactory neuroblastoma is extremely rare. We reported two Korean women who suffered from ectopic ACTH syndrome (EAS) caused by olfactory neuroblastomas. The first patient was a 66-year-old woman who had been diagnosed as olfactory neuroblastoma and refused the management two years before and the second patient was a 37-year-old woman on chemotherapy for olfactory neuroblastoma. In the first case, she presented the Cushingoid appearance with systemic edema and her tumor was removed surgically. ACTH secretion by the tissue was confirmed by immunohistochemistry. By contrast, the second patient presented as severe pneumonia caused by cytomegalovirus and was treated with anti-viral agent followed by chemotherapy and radiotherapy, and her residual mass remained. However, after treatment, both patients' plasma ACTH and cortisol levels returned to normal without any adrenolytic therapy. Considering the causative tumors of EAS can be rarely cured and EAS increases the susceptibility to infections, it is prudent to suppress any hypercortisolemia initially, apart from treating the causal malignancy.

Paraneoplastic Cushing's syndrome in prostate cancer: a difficult management problem

Cushing's syndrome associated with small-cell de-differentiation of prostate cancer is rare, but well described. The detection of Cushing's syndrome in a patient with prostate cancer can be problematical, and when occurring in prostate cancer nearly always implies the development of small-cell transformation. Testosterone levels in these patients are likely to be in the normal range, despite previous castration. The features of Cushing's syndrome contribute considerably to patients' morbidity and probably to their mortality. The syndrome is unlikely to be controlled with inhibitors of steroid synthesis, and chemotherapy is likely to be poorly tolerated, resolving the syndrome in only a few patients. We suggest that bilateral adrenalectomy at an early stage should be considered, possibly as a preliminary to anticancer treatments.

Cushing syndrome associated with prostatic tumor adrenocorticotropic hormone (ACTH) expression after maximal androgen blockade therapy

We report a patient with adenocarcinoma of the prostate, who eventually developed Cushing syndrome due to ectopic adrenocorticotropic hormone (ACTH) secretion from the tumor. At first, maximal androgen blockade (MAB) therapy was effective for the prostate carcinoma, which was positive for prostate-specific antigen (PSA) and negative for ACTH on the biopsy specimen. However, 3 years later, the patient complained of bilateral leg edema. A chest computed tomographic (CT) scan showed bilateral pleural effusion and inflammatory changes, focused on the right upper-lobe. While his PSA was not elevated, and there were no obvious tumor metastases, his serum cortisol and ACTH levels were elevated, without any evidence of lesions that could release ectopic ACTH. Two weeks later, the patient complained of dyspnea and bilateral pleural effusion, and inflammatory changes were worse. Although the patient was administered inhibitors of adrenocorticoid synthesis-metyrapone, they did not have enough clinical efficiency. Steroid pulse therapy was also administered but the patient's severe pneumonia and pleural effusion did not improve and he finally died of respiratory failure. In contrast to the initial biopsy specimen findings, on autopsy, the tumor was negative for PSA but positive for ACTH. Thus, it would appear that the tumor began to produce and release ectopic ACTH after therapy, which resulted in the development of Cushing syndrome in this patient with prostate carcinoma.

Etomidate use for Cushing's syndrome caused by an ectopic adrenocorticotropic hormone-producing tumor

OBJECTIVE

To report the preparation and use of etomidate in a patient with Cushing's syndrome caused by an ectopic adrenocorticotropic hormone (ACTH)-producing tumor.

CASE SUMMARY

A 73-year-old man with a 5 year history of prostate cancer was admitted for symptoms consistent with Cushing's syndrome. He was started on oral metyrapone for elevated serum cortisol, ACTH, and 24 hour urinary unbound cortisol levels. Shortly after starting metyrapone, he was transferred to the medical intensive care unit for new-onset atrial fibrillation, neutropenic fever, and respiratory failure. A nasogastric tube could not be inserted to administer metyrapone. Intravenous etomidate 4 mg/h (0.06 mg/kg/h) was initiated to decrease cortisol production and provide sedation for mechanical ventilation. Despite supportive treatment, the patient died from multiple organ dysfunction.

DISCUSSION

For patients exhibiting signs and symptoms of Cushing's syndrome who have no enteral access, administering etomidate intravenously may be a viable alternative treatment route. Although several articles report the use of etomidate to control cortisol overproduction, the intravenous preparation and stability are discussed only vaguely. In our patient, etomidate was infused via a 30 mL syringe, 2 mg/mL undiluted through a central venous catheter; syringe use was limited to 24 hours. Etomidate should be infused only with continuous monitoring of hemodynamics and periodic assessment of adrenal function.

CONCLUSIONS

When oral or enteral medications cannot be administered and sedation is required in critically ill patients, etomidate is an appropriate intravenous agent for hypercortisolemia. There were no obvious problems with stability when undiluted etomidate 2 mg/mL was infused through a dedicated central venous catheter lumen.

Ectopic adrenocorticotropic hormone syndrome in a case of small cell carcinoma of the bladder manifesting as severe muscle weakness

Ectopic adrenocorticotropic hormone syndrome is a paraneoplastic syndrome associated with small cell carcinoma. However, ectopic adrenocorticotropic hormone syndrome is rare in association with small cell carcinoma of the bladder. We report what we believe to be the first case of ectopic adrenocorticotropic hormone syndrome associated with small cell carcinoma of the bladder that manifested as severe muscle weakness due to hypokalemia. An early diagnosis and aggressive potassium replacement is essential for retaining muscle strength. The patient died of pneumonia less than 2 months after the diagnosis. Severe immunosuppression by excess cortisol production was suspected. Control of cortisol levels before chemotherapy might be beneficial in preventing infective complications.

The medical management of Cushing's syndrome

Cushing's syndrome results from prolonged exposure to excessive circulating glucocorticosteroids, and is associated with significant morbidity and mortality. While the treatment of choice in most patients is surgical, the metabolic consequences of the syndrome, including increased tissue fragility, poor wound healing, hypertension, and diabetes mellitus, increase the risks of such surgery. The hypercortisolemia and its sequelae can be efficiently reversed using medical therapy, either as a temporary measure prior to definitive treatment, or longer term in more difficult cases. Drug treatment has been targeted at the hypothalamic/pituitary level, the adrenal glands, and also at the glucocorticoid receptor level. In this review we discuss the pharmacotherapeutic agents that have been used in Cushing's syndrome, and their efficacy, the monitoring of treatment, and potential therapies that may prove useful in the future in this complex endocrinological disorder.

Ectopic pro-opiomelanocortin syndrome

Ectopic POMC syndrome remains one of the most challenging differential diagnoses in endocrinology. Recent progress in the understanding of the tissue specific regulation of POMC gene expression and new insights into the processing of the POMC peptide in nonpituitary tissues has helped elucidate some of the molecular events leading to ectopic expression and secretion of POMC peptides. Corticotropin and other POMC-derived peptides have diverse effects on adrenal steroidogenesis, growth, and extra-adrenal tissues. Differences in POMC gene regulation in the corticotrope versus ectopic POMC-producing tumors provides a scientific framework for the clinical distinction between eutopic and ectopic Cushing's syndrome. In an attempt to revisit recent basic and clinical advances in the diagnosis of ectopic POMC syndrome the authors undertook an extensive literature review of 530 cases in 197 published papers and provided a molecular biologic, demographic and diagnostic update. According to this review, the four most common causes of ectopic POMC syndrome are the small cell carcinoma of the lung (27%), bronchial carcinoids (21%), islet cell tumor of the pancreas (16%), and thymic carcinoids (10%). Although the clinical features of patients with ectopic POMC syndrome are similar to those with Cushing's disease, subgroup analysis reveals a broad spectrum of severity and progression of signs and symptoms of hypercortisolism. The endocrine workup of a patient with suspected ectopic POMC syndrome includes the establishment of pathologic hypercortisolism, diagnosis of corticotropin dependency, and the differential diagnosis of corticotropin-dependent Cushing's syndrome. The use of a variety of baseline endocrine values, dynamic endocrine testing, and invasive procedures leads to the correct diagnosis in the majority of patients with ectopic POMC syndrome. Diagnostic imaging, including conventional radiological techniques and somatostatin receptor scintigraphy, aids in the correct localization and eventual treatment of ectopic POMC production.