Clinical Guidelines for the Diagnosis and Treatment of Cushing's Disease in Korea

Role of computed tomography in predicting adrenal adenomas with cortisol hypersecretion

OBJECTIVES

To investigate performance of adrenal CT-derived multivariate prediction models in differentiating adenomas with cortisol hypersecretion from the other subtypes.

METHODS

This retrospective study included 127 patients who underwent adrenal CT and had a surgically proven adrenal adenoma. Adenoma subtypes were defined according to biochemical test results: Group A, overt cortisol hypersecretion; Group B, mild cortisol hypersecretion; Group C, aldosterone hypersecretion; and Group D, non-function. Two independent readers analyzed size, attenuation, and washout properties of adenomas, and performed quantitative and qualitative analyses for assessing contralateral adrenal atrophy. Actual and internally validated areas under the curves (AUCs) of adrenal CT-derived multivariate prediction models for differentiating adenomas with cortisol hypersecretion from the other subtypes were assessed.

RESULTS

In differentiating Group A from the other groups, the actual and internally validated AUCs of the prediction model were 0.856 (95% confidence interval [CI]: 0.786, 0.926) and 0.847 (95% CI: 0.695, 0.999) for Reader 1, respectively, and 0.901 (95% CI: 0.845, 0.956) and 0.897 (95% CI: 0.783, 1.000) for Reader 2, respectively. In differentiating Group B from groups C and D, the actual and internally validated AUCs of the prediction model were 0.777 (95% CI: 0.687, 0.866) and 0.760 (95% CI: 0.552, 0.969) for Reader 1, respectively, and 0.783 (95% CI: 0.690, 0.875) and 0.765 (95% CI: 0.553, 0.977) for Reader 2, respectively.

CONCLUSION

Adrenal CT may be useful in differentiating adenomas with cortisol hypersecretion from the other subtypes.

ADVANCES IN KNOWLEDGE

Adrenal CT may benefit in adrenal adenoma subtyping.

Diet quality and dietary acid load in relation to cardiovascular disease mortality: Results from Fasa PERSIAN cohort study

Dietary intake is a determining factor in the morbidity and mortality of chronic disorders. However, not many documents have investigated this relationship. The aim of this study was to evaluate the associations of the Mediterranean dietary score (MDS), Alternative Healthy Eating Index (AHEI), Dietary Inflammatory Index (DII), DASH score, and dietary acid load with cardiovascular disease (CVD) mortality. A total of 2158 CVD patients (mean age of 54.73 ± 8.62 years) from the Fasa cohort study, Iran, participated in the current study. Diet quality indices including DII, AHEI, MDS, DASH, and dietary acid load (NEAP score) were computed using a validated 125-item Food Frequency Questionnaire (FFQ). Cox regression analyses were used to determine HRs and 95% CIs. During a follow-up of 3 years, we documented 59 CVD deaths. After adjusting for relevant confounders (age, gender, family history of CVD, smoking, physical activity, alcohol intake, and HTN) in the final model, we found that higher DII scores and dietary acid load were significantly related to increased mortality due to CVD (HR = 1.11; 95% CI = 1.01-1.24; and HR = 1.02; 95% CI = 1.01-1.03). However, the DASH score was insignificantly associated with decreased CVD mortality by 20.4% (HR = 0.79; 95% CI = 0.57-1.09). There was no significant relationship among AHEI score, MDS, and CVD mortality. This study showed that increasing dietary acidity and the use of inflammatory food compounds could contribute to CVD mortality. Also, adherence to the DASH diet may be associated with reduced CVD mortality.

Dietary acid load and mortality from all causes, CVD and cancer: results from the Golestan Cohort Study

Given the limited studies and controversial results on association between dietary acid load and mortality from CVD and cancers, we aimed to investigate this association in a large population cohort study in Middle East, with a wide range of dietary acid load. The study was conducted on the platform of the Golestan Cohort Study (GCS), which enrolled 50 045 participants in 2004-2008. Dietary intake was assessed using a validated FFQ. Dietary potential renal acid load (PRAL) score was calculated from nutrient intake. Death and its causes were identified and confirmed by two or three physicians. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI for total and cause-specific mortalities. Then, the associations were modelled using restricted cubic splines. PRAL range was -57·36 to +53·81 mEq/d for men and -76·70 to +49·08 for women. During 555 142 person-years of follow-up, we documented 6830 deaths, including 3070 cardiovascular deaths, 1502 cancer deaths and 2258 deaths from other causes. For overall deaths, in final model after adjustment for confounders, participants in the first and fifth quintiles of PRAL had a higher risk of mortality compared with the second quintile of PRAL (HR: 1·08; 95 % CI1·01, 1·16 and HR: 1·07; 95 % CI 1·01, 1·15, respectively); Pfor trend < 0·05). Participants in the first and fifth quintiles of PRAL had a 12 % higher risk of CVD mortality compared with the Q2 of PRAL (HR: 1·12; 95 % CI 1·01-1·25 and HR: 1·12; 95 % CI 1·01, 1·26, respectively; Pfor trend < 0·05). We found that all-cause and CVD mortality rates were higher in the lowest and highest PRAL values, in an approximately U-shaped relation (P-values for the overall association and the non-linear association of energy-adjusted PRAL with total mortality were < 0·001 and < 0·001, and with CVD mortality were 0·008 and 0·003, respectively). Our results highlight unfavourable associations of high acidity and alkalinity of diet with the increased total and CVD mortality risk. It may be important to consider a balanced acid-base diet as a protective strategy to prevent pre-mature death, especially from CVD.

[Modern aspects of surgery for cushing's disease]

Cushing's disease is a severe neuroendocrine disorder caused by chronic hypersecretion of ACTH by pituitary adenoma (corticotropinoma). Surgical resection is a gold standard for this disease resulting stable remission in about 65-95% of cases. Despite benign nature of corticotropinoma, recurrence rate is still higher (25-35%) even in specialized neurosurgical centers. Modifications in surgical strategy can prolong recurrence-free period.

Metabolic changes in serum steroids for diagnosing and subtyping Cushing's syndrome

To evaluate the diagnostic value of serum levels of adrenal steroids for diagnosing and subtyping Cushing's syndrome. Patients diagnosed with endogenous Cushing's syndrome (34 and 19 patients with adrenal and pituitary Cushing's syndrome, respectively) and healthy controls (n = 34) were consecutively enrolled at Seoul National University from 2016 to 2020. Morning serum samples were collected before and 3 months after treatment. Serum steroids were profiled using liquid chromatography-mass spectrometry. The diagnostic value of each and the combination of steroids were assessed using the area under the curve of receiver operating characteristic (AUROC) and decision tree analysis. Tetrahydrocortisone and 6β-hydroxycortisol showed the highest AUROC (0.893 and 0.890, respectively) for the diagnosis of endogenous Cushing's syndrome. The decision tree composed of tetrahydrocortisone and 6β-hydroxycortisol correctly classified 79/87 (90.8 %) subjects. For subtyping into adrenal or pituitary Cushing's syndrome, dehydroepiandrosterone sulfate (DHEA-S) showed the highest AUROC (0.988), which was similar to that of plasma ACTH (0.994, P = 0.458). The decision tree composed of only DHEA-S correctly classified 51/53 (96.2 %) of the Cushing's syndrome subtype. DHEA-S showed a significant linear correlation with the plasma ACTH level, but not with the 24 -h urine free cortisol or dexamethasone suppression test results. All steroids, except allo-tetrahydrocortisol and tetrahydrocortisone, decreased significantly at 3 months post-treatment with similar patterns in both adrenal and pituitary Cushing's syndrome. Serum steroid profiling using a single morning serum sample provides valuable information for diagnosing and subtyping Cushing's syndrome.

[Pituitary microadenomas - current diagnostic and treatment methods]

According to previously accepted criteria, pituitary microadenoma is characterized by a diameter of less than 10 mm. Improvement and widespread use of MRI are accompanied by increased incidence of diagnosis of these neoplasms. Pituitary microadenomas is an extremely heterogeneous group of tumors with different biological behavior, endocrine secretion and clinical symptoms despite the common MR characteristics. Treatment is mainly determined by endocrine secretion. Endocrine-active microadenoma requires medication (in case of microprolactinoma) and surgical treatment (in case of microsomatotropinoma and ACTH-releasing tumor). Follow-up is advisable for endocrine-inactive microadenoma (microincidentaloma). Modern data on the incidence, clinical and endocrine features, diagnosis and treatment of various pituitary microadenomas are discussed in the article.

Usefulness of prolactin measurement in inferior petrosal sinus sampling with desmopressin for Cushing's syndrome

Background: Bilateral inferior petrosal sinus sampling (IPSS) is used to distinguish pituitary from ectopic adrenocorticotropin (ACTH) excess in patients with ACTH-dependent Cushing's syndrome. Our objective was to examine the utility of prolactin measurement during IPSS with desmopressin (DDAVP) stimulation in localization of the source of ACTH excess.Method: Retrospective review of 20 patients with ACTH-dependent Cushing's syndrome who underwent IPSS with DDAVP stimulation. Baseline, DDAVP-stimulated, and prolactin-normalized ACTH IPS:P (inferior petrosal sinus to peripheral) ratios were calculated. Cut-off values for each test were obtained from receiver-operating characteristic (ROC) curve analysis.Results: Fifteen patients had Cushing disease (CD), and five were diagnosed with ectopic ACTH syndrome (EAS). For the baseline ACTH IPS:P ratio of ≥2, the diagnostic sensitivity (80%), specificity (100%), positive predictive value (PPV) (100%) and negative predictive value (NPV) (62.5%) were calculated. These values for DDAVP-stimulated IPS:P ACTH ratio ≥ 3, were 86.7%, 100%, 100% and 71.4%, respectively. The corresponding value for the prolactin-normalized ACTH IPS:P ratio ≥ 0.8 were 86.6%, 80%, 92.8% and 66.7%. The cut-off value for the baseline, DDAVP-stimulated and prolactin-normalized ACTH IPS:P ratios were 1.76, 3.9, and 0.33, respectively.Conclusion: Prolactin-normalized ACTH IPS:P ratio measurement showed comparable sensitivity and less specificity than baseline/DDAVP-stimulated IPS/P ACTH ratios. Moreover, when baseline and stimulated IPS/P ACTH tests were discordant, prolactin-normalized ACTH IPS: P ratio correctly localized the source of ACTH excess. The sensitivity of the test increased, applying a prolactin-normalized ACTH IPS: P ratio ≥0.33.

Hormonal aggressiveness according to the expression of cellular markers in corticotroph adenomas

PURPOSE

The molecular mechanisms underlying tumor growth in Cushing's disease (CD) still remain a challenge. Moreover, clinical manifestations of CD may vary depending on hormonal activity; however, factors involved in the hormonal aggressiveness of adrenocorticotropic hormone (ACTH)-secreting pituitary tumors have not been fully clarified. We investigated the association between the expression of cellular markers regarding pituitary tumor progression and initial or postoperative hormone levels in patients with CD.

METHODS

Tumor tissues from 28 corticotroph adenomas (female 26, male 2, mean age 39.21 ± 10.39 years) were subject to immunohistochemical study using the following antibodies: pituitary tumor-transforming gene 1 (PTTG1), cyclin D1, p16, p27, brahma related-gene 1 (Brg1), and Ki-67. We then analyzed the relationship between each cellular marker expression and hormone levels, including 24 h urinary free cortisol (UFC), plasma ACTH, and serum cortisol.

RESULTS

PTTG1 and Ki-67 were expressed in 100% and 50% of patients, respectively. However, the levels did not reflect initial hormonal activity. The cyclin D1-negative group showed higher serum cortisol levels compared to the cyclin D1-positive group (p = 0.01). The 24 h UFC levels were significantly higher in the p27-negative group than in the p27-positive group (p = 0.04), whereas the Brg1-positive group revealed higher serum cortisol levels than in the Brg1-negative group (p = 0.02).

CONCLUSIONS

Although PTTG1 and Ki-67 play an essential role in developing ACTH-secreting tumors, cyclin D1, p27, and Brg1 may be better biomarkers to determine hormonal aggressiveness of the tumor. Further research is needed to understand the influence of cellular markers on hormonal activity in CD.

Clinical Parameters to Distinguish Silent Corticotroph Adenomas from Other Nonfunctioning Pituitary Adenomas

BACKGROUND

It is difficult to distinguish silent corticotroph adenomas (SCAs) from other nonfunctioning pituitary adenomas (NFPAs) preoperatively. This study aimed to determine the preoperative clinical parameters associated with SCAs.

METHODS

This was a retrospective single-center study of patients who underwent surgery for NFPAs during 2011-2016 in our tertiary hospital and who had preoperative combined pituitary function test (CPFT) and immunohistochemical staining results available. After we excluded patients with increased 24-hour urinary free cortisol to preclude overt Cushing's disease, 341 patients were finally enrolled. The medical records, including the CPFT and immunohistochemistry results, of the patients were reviewed.

RESULTS

The age and tumor size were similar between patients with SCAs and other NFPAs. The SCA group had a greater proportion of women (89.2% vs. 57.6%, P < 0.001), cavernous sinus invasion (35.1% vs. 20.7%, P = 0.047), and intratumoral hemorrhage on preoperative sella magnetic resonance imaging (32.4% vs. 9.2%, P < 0.001) compared with the NFPA group. In the preoperative CPFT, the cortisol response was not significantly different between groups. However, the peak adrenocorticotropic hormone (ACTH) (67.80 ± 49.83 vs. 85.67 ± 78.97 pg/mL, P = 0.061) tended to be lower, and the ΔACTH (53.71 ± 50.14 vs. 72.67 ± 75.82 pg/mL, P = 0.046) was significantly lower in SCAs. After we excluded patients with preoperative hypopituitarism caused by mass effects, the peak ACTH (69.39 ± 39.45 vs. 119.75 ± 89.84 pg/mL, P = 0.001) and ΔACTH (58.58 ± 36.51 vs. 107.66 ± 86.05 pg/mL, P = 0.001) were significantly lower in SCAs than in other NFPAs.

CONCLUSIONS

Female sex, cavernous sinus invasion, intratumoral hemorrhage on sella magnetic resonance imaging, and decreased ACTH response in the CPFT are independent indicators of SCAs.

Surgical management of adrenocorticotropic hormone-secreting pituitary adenomas

Cushing's disease is defined as hypercortisolemia caused by secretion of adrenocorticotropic hormone from a pituitary adenoma. The diagnosis of Cushing's disease is based on clinical symptoms, laboratory and imaging findings. Once an adrenocorticotropic-hormone-secreting adenoma is found, the standard of care is transsphenoidal adenomectomy. MRI negative microadenomas and large, invasive macroadenomas provide a surgical and clinical challenge and are best handled at high volume centers. Multiple options exist for refractory disease or recurrence, including repeat surgery, radiosurgery and radiotherapy, medical management and bilateral adrenalectomy.