Diagnosis of adrenal adenoma: value of central spot of high-intensity hyperintense rim sign and homogeneous isointensity to liver on gadolinium-enhanced fat-suppressed spin-echo MR images

Management of adrenal incidentalomas: European Society of Endocrinology Clinical Practice Guideline in collaboration with the European Network for the Study of Adrenal Tumors

: By definition, an adrenal incidentaloma is an asymptomatic adrenal mass detected on imaging not performed for suspected adrenal disease. In most cases, adrenal incidentalomas are nonfunctioning adrenocortical adenomas, but may also represent conditions requiring therapeutic intervention (e.g. adrenocortical carcinoma, pheochromocytoma, hormone-producing adenoma or metastasis). The purpose of this guideline is to provide clinicians with best possible evidence-based recommendations for clinical management of patients with adrenal incidentalomas based on the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. We predefined four main clinical questions crucial for the management of adrenal incidentaloma patients, addressing these four with systematic literature searches: (A) How to assess risk of malignancy?; (B) How to define and manage low-level autonomous cortisol secretion, formerly called 'subclinical' Cushing's syndrome?; (C) Who should have surgical treatment and how should it be performed?; (D) What follow-up is indicated if the adrenal incidentaloma is not surgically removed? SELECTED RECOMMENDATIONS: (i) At the time of initial detection of an adrenal mass establishing whether the mass is benign or malignant is an important aim to avoid cumbersome and expensive follow-up imaging in those with benign disease. (ii) To exclude cortisol excess, a 1mg overnight dexamethasone suppression test should be performed (applying a cut-off value of serum cortisol ≤50nmol/L (1.8µg/dL)). (iii) For patients without clinical signs of overt Cushing's syndrome but serum cortisol levels post 1mg dexamethasone >138nmol/L (>5µg/dL), we propose the term 'autonomous cortisol secretion'. (iv) All patients with '(possible) autonomous cortisol' secretion should be screened for hypertension and type 2 diabetes mellitus, to ensure these are appropriately treated. (v) Surgical treatment should be considered in an individualized approach in patients with 'autonomous cortisol secretion' who also have comorbidities that are potentially related to cortisol excess. (vi) In principle, the appropriateness of surgical intervention should be guided by the likelihood of malignancy, the presence and degree of hormone excess, age, general health and patient preference. (vii) Surgery is not usually indicated in patients with an asymptomatic, nonfunctioning unilateral adrenal mass and obvious benign features on imaging studies. We provide guidance on which surgical approach should be considered for adrenal masses with radiological findings suspicious of malignancy. Furthermore, we offer recommendations for the follow-up of patients with adrenal incidentaloma who do not undergo adrenal surgery, for those with bilateral incidentalomas, for patients with extra-adrenal malignancy and adrenal masses and for young and elderly patients with adrenal incidentalomas.

MANAGEMENT OF ENDOCRINE DISEASE: Imaging for the diagnosis of malignancy in incidentally discovered adrenal masses: a systematic review and meta-analysis

OBJECTIVE

Adrenal masses are incidentally discovered in 5% of CT scans. In 2013/2014, 81 million CT examinations were undertaken in the USA and 5 million in the UK. However, uncertainty remains around the optimal imaging approach for diagnosing malignancy. We aimed to review the evidence on the accuracy of imaging tests for differentiating malignant from benign adrenal masses.

DESIGN

A systematic review and meta-analysis was conducted.

METHODS

We searched MEDLINE, EMBASE, Cochrane CENTRAL Register of Controlled Trials, Science Citation Index, Conference Proceedings Citation Index, and ZETOC (January 1990 to August 2015). We included studies evaluating the accuracy of CT, MRI, or (18)F-fluoro-deoxyglucose (FDG)-PET compared with an adequate histological or imaging-based follow-up reference standard.

RESULTS

We identified 37 studies suitable for inclusion, after screening 5469 references and 525 full-text articles. Studies evaluated the accuracy of CT (n=16), MRI (n=15), and FDG-PET (n=9) and were generally small and at high or unclear risk of bias. Only 19 studies were eligible for meta-analysis. Limited data suggest that CT density >10HU has high sensitivity for detection of adrenal malignancy in participants with no prior indication for adrenal imaging, that is, masses with ≤10HU are unlikely to be malignant. All other estimates of test performance are based on too small numbers.

CONCLUSIONS

Despite their widespread use in routine assessment, there is insufficient evidence for the diagnostic value of individual imaging tests in distinguishing benign from malignant adrenal masses. Future research is urgently needed and should include prospective test validation studies for imaging and novel diagnostic approaches alongside detailed health economics analysis.

Dynamic contrast enhanced MRI in the differential diagnosis of adrenal adenomas and malignant adrenal masses

OBJECTIVE

To evaluate the value of dynamic MR imaging in the differential diagnosis of adrenal adenomas and malignant tumors, especially in cases with atypical adenomas.

MATERIALS AND METHODS

Sixty-four masses (48 adenomas, 16 malignant tumors) were included in this prospective study. Signal loss of masses was evaluated using chemical shift MR imaging. Five dynamic series of T1-weighted spoiled gradient echo (FFE) images were obtained, with the acquisition starting simultaneously with i.v. contrast administration (0-100 s) followed by a T1-weighted FFE sequence in the late phase (5th minute). Contrast enhancement patterns in the early (25th second) and late (5th minute) phase images were evaluated. For the quantitative evaluation, signal intensity (SI)-time curves were obtained according to the SIs on the 0th, 25th, 50th 75th and 100th second. Also, the wash-in rate, maximum relative enhancement, time-to-peak, and wash-out of contrast at 100 s of masses in both groups were calculated. The statistical significance was determined by Mann-Whitney U test. To evaluate the diagnostic performance of the quantitative tests, receiver operating characteristic (ROC) analysis was performed.

RESULTS

Chemical shift MR imaging was able to differentiate 44 out of 48 adenomas (91.7%) from non-adenomas. The 4 adenomas (8.3%) which could not be differentiated from non-adenomas by this technique did not exhibit signal loss on out-of-phase images. With a cut-off value of 30, SI indices of adenomas had a sensitivity of 93.8%, specificity of 100% and a positive predictive value of 100%. On visual evaluation of dynamic MR imaging, early phase contrast enhancement patterns were homogeneous in 75% and punctate in 20,83% of the adenomas; while patchy in 56.25% and peripheral in 25% of the malignant tumors. On the late phase images 58.33% of the adenomas showed peripheral ring-shaped enhancement and 10.41% showed heterogeneous enhancement. All of the malignant masses showed heterogeneous enhancement. At the 25th second, the SIs and wash-in rates of the adenomas were significantly higher than those of the malignant masses (p=0.010). Time-to-peak enhancement of the malignant masses was significantly longer than that of the adenomas. With a cut-off value of 52.85 s, the time-to-peak enhancement had 87.5% sensitivity and 80% specificity.

CONCLUSION

Chemical shift MR has a high sensitivity and specificity in the differential diagnosis of adenomas and malignant adrenal masses. However, taking into consideration only the atypical adenomas, chemical shift MRI is of no diagnostic value. Although the diagnostic value of dynamic MRI is lower than chemical shift MRI, in the atypical cases contrast enhancement patterns and time-to-peak and wash-in rates derived from SI-time curve of dynamic MRI give are contributory to the results of chemical shift MRI.

Fine-needle aspiration cytology of adrenal masses in noncancer patients: clinicoradiologic and histologic correlations in functioning and nonfunctioning tumors

BACKGROUND

Image-guided, fine-needle aspiration (FNA) cytology is performed currently in patients with malignant disease who have suspected adrenal metastases. The objective of this study was to evaluate the usefulness and safety of FNA cytology in patients with incidental adrenal masses and functioning tumors.

METHODS

Computed tomography (CT)-guided or ultrasound-guided aspirates using 21-23-gauge needles were performed successfully in 70 patients with functioning (n = 38 patients) and nonfunctioning (n = 32 patients) adrenal masses (median size, 4 cm; range, 3-12 cm) that were detected previously by CT scans.

RESULTS

Definitive histology was available in 68 patients (97.1%), showing 53 benign tumors (77.9%), 11 primitive malignant tumors (16.2%), and 4 unsuspected adrenal metastases (5.9%) in patients with unknown primary tumors. In two patients with aspirate reports that ruled out malignancy, the mass was unchanged on CT scan follow-up; thus, they were considered benign lesions. The benign masses were significantly smaller (P < 0.01), although seven malignant tumors (46.7%) measured 3-4 cm in greatest dimension, and eight benign lesions (14.5%) measured 5-6 cm in greatest dimension. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 96.4%, 83.3%, 91.4%, and 90.0%, respectively, for CT scan and 93.3%, 100%, 100%, 98.2%, and 98.6%, respectively, for FNA cytology. The morbidity rate of image-guided FNA cytology was 4.3% (two patients with self-limited, asymptomatic pneumothorax and one patient with spontaneously resolved adrenal hematoma).

CONCLUSIONS

Adrenal FNA cytology represents a safe and specific procedure for evaluating patients with adrenal masses measuring > 2 cm in greatest dimension. FNA is able to reveal malignancies and unsuspected pheochromocytomas and should be performed in all patients with adrenal tumors whenever requested for surgical planning.

Management of incidentally discovered adrenal masses and risk of malignancy

BACKGROUND

Incidentally discovered adrenal masses of more than 1 cm in size are relatively frequent, but the correct management of such lesions is not well established.

METHODS

Between 1980 and 1999, 158 patients (73 men [46.2%] and 85 women [53.8%]; median age, 58 years) with adrenal incidentalomas of more than 2 cm in size were observed. Sixty-eight patients (43.0%) underwent adrenalectomy. The main reasons for surgery were (1) suspicious computed tomography (CT) scan or magnetic resonance imaging (MRI) appearance or no uptake at the 75-Se-norcholesterol scintigraphy (NCS; n = 22 patients), (2) an increase in the size of the mass of more than l cm (n = 15 patients), (3) subclinical endocrine hyperfunction (n = 14 patients), and (4) mass size of more than 5 cm (n = 22 patients), with imaging-guided fine-needle aspiration biopsy with spinal-type narrow-gauge needle (FNAB) that suggested malignancy (n = 5 patients).

RESULTS

Pathologic examination showed 39 adrenocortical adenomas (57.4%), 20 adrenal malignancies (29.4%; carcinomas, 15; unsuspected metastases, 3; nonfunctioning malignant pheochromocytomas, 2), and 9 various benign lesions (13.2%). All masses that increased in size were benign. Seven malignant tumors (46.7%) were 3 to 4 cm in size, and 14 benign lesions (29.1%) were 5 to 6 cm in size. Sensitivity and specificity in the detection of malignancy were 100% and 100% for NCS (n = 34 patients) and FNAB (n = 19 patients), 75.0% and 93.7% for CT scan (n = 68 patients), and 87.5% and 100% for MRI (n = 26 patients), respectively.

CONCLUSIONS

To differentiate benign and malignant incidentalomas, NCS and FNAB are more sensitive than CT scan and MRI; size criteria are of little value.

Adrenocortical carcinoma in children. Review and recent innovations

Adrenocortical carcinoma in childhood is a rare potentially fatal disease. Despite its often dramatic presentation, there typically has been a distressingly long delay between the onset of symptoms and the time of diagnosis. This delay undoubtedly has contributed to the historically poor prognosis in these children by permitting the disease to reach an advanced stage before treatment is started. It is imperative that the physician recognizes the endocrine manifestations of these tumors early and has a high index of suspicion. Although biochemical and histologic evaluations are helpful, they often cannot differentiate benign lesions from malignant neoplasms and should not unduly delay intervention. Aggressive complete surgical resection continues to be the mainstay of treatment and is the best prognosticator of overall survival. The role of adjuvant therapy and chemotherapy continues to evolve. Molecular studies have increased understanding of cancer biology and may provide possible novel therapeutic approaches in the future. It is hoped that increased familiarity with this unusual tumor will result in earlier detection, prompt intervention, and improved survival for children with adrenocortical carcinoma.