Severe hypertension and hypokalemia as first clinical manifestations in ectopic Cushing's syndrome

Management of small cell lung cancer complicated with paraneoplastic Cushing's syndrome: a systematic literature review

Paraneoplastic Cushing's syndrome (PCS) is a rare, but clinically important feature of small cell lung cancer (SCLC) that is associated with even worse prognosis. To identify key considerations in comprehensive management of SCLC patients complicated with PCS, we conducted a systematic review of relevant reports on PubMed and Web of Science, focusing on SCLC with PCS cases. The systematic review analyzed 61 reports published between 1985 and 2022 with a total of 157 SCLC patients included. Out of the 157 patients, 132 (84.1%) patients across 58 (95.1%) reports were diagnosed with ectopic Cushing's syndrome. The immunohistochemical (IHC) staining for adrenocorticotropic hormone (ACTH) was performed on 30 (19.1%) patients across 22 (36.1%) reports and demonstrated encouraging performance. For treatment, chemotherapy and ketoconazole were utilized in 50 (81.97%) and 24 (39.34%) reports, respectively. Regarding cause of death, infection and cancer were equally frequent, each being recorded in 17 (27.87%) reports. To conclude, the majority of PCS cases in SCLC patients were caused by ectopic hormone secretion. In order to make a differential diagnosis, it is recommended to utilize IHC staining for a specific hormone such as ACTH or corticotropin-releasing hormone. In the comprehensive treatment of SCLC with PCS patients, effective management of hypercortisolism and potent safeguarding against infection play two crucial roles. Ultimately, further confirmations are required regarding the specificity and accuracy of IHC staining technique as well as the efficacy and safety of immunotherapy in the treatment of SCLC with PCS patients.

Hidden hypercortisolism: a too frequently neglected clinical condition

PURPOSE

Classic Cushing's syndrome (CS) is a severe disease characterized by central obesity, hypertension, easy bruising, striae rubrae, buffalo hump, proximal myopathy and hypertricosis. However, several CS cases have also been reported with unusual or camouflaged manifestations. In recent years, several authors investigated the prevalence of "hidden hypercortisolism" (HidHyCo) among subjects affected with bone fragility, hypertension and type 2 diabetes mellitus (DM2). The prevalence of the HidHyCo is estimated to be much higher than that of classic CS. However, similarly to classic CS, HidHyCo is known to increase the risk of fractures, cardiovascular disease and mortality.

METHODS

We reviewed all published cases of unusual presentations of hypercortisolism and studies specifically assessing the HidHyCo prevalence in diabetic, osteoporotic and hypertensive patients.

RESULTS

We found 49 HidHyCo cases, in whom bone fragility, hypertension and diabetes were the presenting manifestations of an otherwise silent hypercortisolism. Amongst these cases, 34.7%, 32.7%, 6.1% and 19.0%, respectively, had bone fragility, hypertension, DM2 or hypertension plus DM2 as the sole clinical manifestations of HidHyCo. Overall, 25% of HidHyCo cases were of pituitary origin, and bone fragility was the very prevalent first manifestation among them. In population studies, it is possible to estimate that 1-4% of patients with apparent primary osteoporosis has a HidHyCo and the prevalence of this condition among diabetics ranges between 3.4 and 10%.

CONCLUSION

These data indicate that patients with resistant or suddenly worsening hypertension or DM2 or unexplainable bone fragility should be screened for HidHyCo using the most recently approved sensitive cut-offs.

Association of hypokalemia with cortisol and ACTH levels in Cushing's disease

Hypokalemia is a common feature in patients with Cushing's syndrome (CS). Whether the occurrence of hypokalemia is associated with cortisol and adrenocorticotropic hormone (ACTH) levels is still unclear. Approximately 80% of cases of endogenous CS are due to Cushing's disease (CD). The purpose of this study was to determine the association of hypokalemia with cortisol and ACTH levels in patients with CD. The retrospective study included 195 patients with CD referred to our medical center from January 2011 to December 2017. The results show that 25.64% (50/195) of the patients had hypokalemia. The 24-h urinary free cortisol (UFC) and plasma cortisol levels were significantly higher in patients with hypokalemia than those with normokalemia (P < 0.05). Plasma ACTH levels were similar between the patients with hypokalemia and normokalemia (P > 0.05). Cortisol levels were negatively correlated with plasma potassium levels (08:00: r = -0.344 (P < 0.01), 00:00: r = -0.435 (P < 0.01); 24-h UFC: r = -0.281 (P < 0.05)). There was no significant correlation between the plasma ACTH and potassium (08:00: r = -0.093 (P > 0.05), 00:00: r = -0.184 (P > 0.050)). Our current data suggest that cortisol level, instead of ACTH level, is correlated with plasma potassium level. A high cortisol level may be the principal cause of hypokalemia.

Hypertension and severe hypokalaemia associated with ectopic ACTH production

Ectopic adrenocorticotropic hormone (ACTH) secretion represents 5%-10% of cases of Cushing's syndrome (CS), and approximately 50%-60% of these arise from neuroendocrine lung tumours, including small-cell lung cancer (SCLC). We report a 42-year-old man admitted with hypertension, metabolic alkalosis and severe hypokalaemia. On physical examination, centripetal obesity with 'moon face' and 'buffalo's hump' were identified, and wheezing on left lung was heard. A markedly elevated serum cortisol, ACTH and urine free cortisol production supported the diagnosis of CS. Chest CT showed a left hilar mass with metastasis to the liver, adrenal glands and lymph nodes. Bronchoscopy identified bronchial infiltration by SCLC. Treatment with metyrapone and chemotherapy was started. Despite initial improvement, progressive clinical deterioration occurred, culminating in death 1 year after diagnosis. Ectopic ACTH secretion is uncommon but should be suspected in patients with severe hypokalaemia, hypertension and metabolic alkalosis, especially in the context of lung cancer.

A retrospective analysis of postoperative hypokalemia in pituitary adenomas after transsphenoidal surgery

BACKGROUND

Pituitary adenoma is one of the most common intracranial neoplasms, and its primary treatment is endoscopic endonasal transsphenoidal tumorectomy. Postoperative hypokalemia in these patients is a common complication, and is associated with morbidity and mortality. This study aimed to analyze the etiopathology of postoperative hypokalemia in pituitary adenomas after endoscopic transsphenoidal surgery.

METHODS AND MATERIALS

This retrospective study included 181 pituitary adenomas confirmed by histopathology. Unconditional logistic regression analysis was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Repeated measures ANOVA was used to analyze change in serum potassium levels at different time points.

RESULTS

Multiple Logistic regression analysis revealed that only ACTH-pituitary adenoma (OR = 4.92, 95% CI [1.18-20.48], P = 0.029) had a significant association with postoperative hypokalemia. Moreover, the overall mean serum potassium concentration was significantly lower in the ACTH versus the non-ACTH group (3.34 mmol/L vs. 3.79 mmol/L, P = 0.001). Postoperative hypokalemia was predominantly found in patients with ACTH-pituitary adenoma (P = 0.033).

CONCLUSIONS

ACTH-pituitary adenomas may be an independent factor related postoperative hypokalemia in patients despite conventional potassium supplementation in the immediate postoperative period.

Anesthetic management of emergent laparoscopic bilateral adrenalectomy in a patient with a life-threatening cortisol crisis

Cushing syndrome may rarely present with life-threatening hypercortisolism, manifested by hypertension, hypokalemia, hyperglycemia, and edema. If medical treatment proves ineffective in ameliorating the symptoms, emergent rescue adrenalectomy may be the only way to relieve the crisis. We describe the anesthetic management of a patient with an ectopic adrenocorticotropic hormone-secreting tumor, whose condition was rapidly deteriorating due to severe cortisol excess, and emergent adrenalectomy was the only available therapeutic modality. Despite severe metabolic derangement, edema, and incipient respiratory failure, emergent bilateral laparoscopic adrenalectomy was performed and the patient improved sufficiently to undergo surgery for the ectopic lesion without incident.

An ectopic ACTH-producing small cell lung carcinoma associated with enhanced corticosteroid biosynthesis in the peritumoral areas of adrenal metastasis

A 60-year-old Japanese male presented with swelling of bilateral cervical lymph nodes was subsequently diagnosed as the late stage of primary small cell lung carcinoma (SCLC). He was then treated with cisplatin and irinotecan as first-line chemotherapy, but hypokalemia with muscle weakness of the bilateral legs became gradually noticeable following two months of effective chemotherapy. A computed tomography (CT) scan revealed enlargement of bilateral adrenal glands and abdominal and mediastinal lymph nodes, though primary lung tumor remained the same in size. An ectopic ACTH-producing syndrome (EAS) was subsequently revealed by the following endocrinological studies. Hypokalemia was clinically improved by the treatment with metyrapone and the second-line chemotherapy with amrubicin for SCLC was started, but the patient died 12 days after the second-line chemotherapy. Post-mortem examination revealed ACTH immunoreactivity in tumor cells of all the metastatic lesions. Non-neoplastic adrenal cortex demonstrated hyperplasia associated with lipid depletion and marked expression of steroidogenic enzymes, especially in cortical cells around tumor infiltration, suggestive of paracrine ACTH stimulation of cortisol production. This is the first report evaluating expression of steroidogenic enzymes in adrenal cortex especially adjacent to the adrenal metastasis in the patients with EAS due to SCLC. These findings suggest that ACTH producing adrenal metastasis can induce EAS more frequently and severely, and that the symptoms and examination of EAS should be monitored carefully in the patients with adrenal metastasis of SCLC.