Predicting malignancy in adrenal incidentaloma and evaluation of a novel risk stratification algorithm

Impact of Size Thresholds on the Diagnosis of Incidental Adrenal Lesions: A Systematic Review and Meta-Analysis

BACKGROUND

Preferred size-threshold recommendations for management of incidental adrenal lesions remain controversial.

PURPOSE

This meta-analysis aimed to compare the diagnostic accuracy of different size thresholds for detecting malignancy in patients with incidental adrenal lesions on imaging.

MATERIALS AND METHODS

A systematic review of MEDLINE, Embase, Scopus, the Cochrane Library, and the gray literature, covering the period from inception to September 2021, was performed. Studies with >10 patients evaluating the diagnostic accuracy of imaging size thresholds for detecting malignancy in patients with incidental adrenal lesions and no prior history of cancer were included. Study, clinical, imaging, and accuracy data for eligible studies were independently acquired by two reviewers. Primary meta-analysis was performed using a bivariate mixed-effects regression model. Risk of bias was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.

RESULTS

From 2,690 citations, 40 studies (9,794 patients with mean age ranging from 41 to 66 years) were included. Most (36 of 40) were retrospective single-center studies. CT with or without MRI served as the index test(s). Sensitivity and specificity values, respectively, by size threshold used in the included studies were as follows: 85% (95% confidence interval [CI] 74%-91%) and 39% (95% CI 23%-57%) for 3-cm thresholds; 85% (95% CI 78%-90%) and 75% (95% CI 62%-85%) for 4-cm thresholds; 70% (95% CI 56%-81%) and 74% (95% CI 59%-85%) for 5-cm thresholds; and 75% (95% CI 67%-82%) and 77% (95% CI 62%-87%) for 6-cm thresholds. No cause for variability in sensitivity or specificity was identified on subgroup analysis of the 4-cm threshold. Nearly half of the studies (19 of 40) had at least one QUADAS-2 domain with a high risk of bias.

CONCLUSIONS

A 4-cm size threshold demonstrates the highest combined sensitivity and specificity, with a preserved specificity compared with higher size thresholds, but with a trend toward improved sensitivity. Future research reevaluating 4-5 cm size thresholds while excluding characteristically benign lesions by imaging may help redefine a size threshold that has improved specificity but preserved sensitivity, compared with the existing 4-cm threshold.

An adrenal incidentaloma that had appeared to produce dehydroepiandrosterone-sulfate in excess before immunohistochemical study of the tumor

Adrenal incidentaloma is a clinically unapparent adrenal mass more than one cm in diameter detected during imaging performed not for adrenal disease. A 34-year-old man was evaluated for AI with a diameter of 3.5 cm in the left adrenal. He was obese with body mass index of 33,9. Blood pressure was 110-120/90 mmHg. The general laboratory tests were unremarkable. An adrenal hormone screening set revealed that ACTH was 6.9 pg/mL, cortisol 14.9 μg/dL, renin activity 0.9 ng/mL/h, aldosterone 79.4 pg/mL, dehydroepiandrosterone-sulfate (DHEA-S) measured on two occasions 5,217 ng/mL and 6,477 ng/mL (gender- and age-adjusted reference values, 1,060-4,640 ng/mL). The levels of metanephrine and normetanephrine were normal. The tumor was thought to produce solely DHEA-S. The excised left adrenal tissue contained a tumor with a diameter of 26 mm and neighboring adrenal tissue. The tumor consisted mostly of acidophil cells without necrosis, capsular or vascular invasion, and mitosis. Immunohistochemical study revealed followings: the cells of the tumors were stained positive for 3β-hydroxysteroid dehydrogenase, and 17α-hydroxylase, and 11β-hydroxylase, weakly positive for DHEA sulphotransferase, and negative for aldosterone synthetase. The atrophy of neighboring tissue was presumably caused by excess cortisol production. Four months after surgery, the cortisol level was 11.2 μg/dL and DHEA-S level 1,462 ng/mL. The tumor is considered to be a cortisol-producing adenoma with modestly excessive DHEA-S production rather than isolated DHEA-S-producing adenoma. Immunohistochemical study of steroidogenic enzymes is a valuable addition to blood hormone measurement to clarify steroid production profile.

Incidental Adrenal Masses: Adherence to Guidelines and Methods to Improve Initial Follow-Up, A Systematic Review

OBJECTIVE

Incidental adrenal masses (IAMs) are detected in approximately 1%-2% of abdominal computed tomography (CT) scans. Recent estimates suggest that more than 70-million relevant CT scans are performed annually in the United States; thus, IAMs represent a significant clinical entity. Most clinical guidelines recommend an initial follow-up evaluation that includes imaging and biochemical testing after index IAM detection.

METHODS

Systematic review of literature in the PubMed, EMBASE and Web of Science databases to determine whether guidelines regarding IAM evaluation are followed and to identify effective management strategies. Our initial search was in January 2018 and updated in November, 2019.

RESULTS

31 studies met inclusion criteria. In most institutions, only a minority of patients with IAMs undergo initial follow-up imaging (median 34%, IQR 20%-50%) or biochemical testing (median 18%, IQR 15%-28%). 2 interventions shown to improve IAM evaluation are IAM-specific recommendations in radiology reports and dedicated multi-disciplinary teams. Interventions focused solely on alerting the ordering clinician or primary care provider to the presence of an IAM have not demonstrated effectiveness. Patients who are referred to an endocrinologist are more likely to have a complete IAM evaluation, but few are referred.

DISCUSSION

Most patients with an IAM do not have an initial evaluation. The radiology report has been identified as a key component in determining whether IAMs are evaluated appropriately. Care teams dedicated to management of incidental radiographic findings also improve IAM follow-up. Although the evidence base is sparse, these interventions may be a starting point for further inquiry into optimizing care in this common clinical scenario.

Prevalence of Renal Masses Suspected of Malignancy and Adrenal Incidentalomas in Patients With Abdominal Aortic Aneurysm

OBJECTIVE

The aim of our study was to assess the prevalence of renal masses suspected of malignancy and adrenal incidentalomas in patients with abdominal aortic aneurysm based on the computed tomography angiography (CTA).

METHODS

In the retrospective cross-sectional study, the CTA scans of patients with abdominal aortic aneurysms and thoraco-abdominal aortic aneurysms type II-IV were assessed. Patients with thoraco-abdominal aortic aneurysms type I and V and history of abdominal aortic surgery were excluded from the study.

RESULTS

Study group comprised 937 patients with a median age of 73.0 years, 83.8% of whom were male. CTA revealed renal tumors in 11 patients (1.2% of the study population) with a median size of 26 mm (interquartile range 20-50). Adrenal incidentalomas were found in 61 patients (6.5% of the study population). In 20 patients (2.1%) adrenal lesions were found bilaterally.

CONCLUSION

In the described cohort, the renal and adrenal tumors were relatively common findings among patients with abdominal aortic aneurysm and thoraco-abdominal aortic aneurysms type II-IV. Both anaesthesiologists and surgeons should be vigilant about the possibility of such coexistence in order to provide the patients with the best possible perioperative care and an optimal surgical modality.

Robotic Adrenalectomy: Are We Expanding the Indications of Minimally Invasive Surgery?

INTRODUCTION

Laparoscopic adrenalectomy (LA) is accepted as the gold standard treatment for most adrenal pathologies. Open surgery is still considered the standard of care for large tumors and malignancies. In the past decade, robotic adrenalectomy (RA) has become an alternative to the laparoscopic and open approaches. The aim of this study was to analyze perioperative and postoperative outcomes in a series of consecutive nonselected patients undergoing a RA, to determine whether factors that negatively affect outcomes in LA (body mass index [BMI], size, and side of the tumor) have the same impact in RA.

MATERIALS AND METHODS

This is a single-center single-surgeon retrospective study with 43 patients who underwent a RA. Patients were divided into different groups according to tumor size (cutoff values of 5 or 8 cm), tumor side (left/right), and BMI (cutoff value of kg/m²). Perioperative and postoperative outcomes included operative time, length of hospital stay, blood loss, readmissions, complications, and conversions to open.

RESULTS

There were no significant differences between the groups with tumors <5 cm versus ≥5 cm regarding gender, age, race, BMI, American Society of Anesthesiologists (ASA) score, history of previous abdominal surgery, tumor side, and histopathological diagnosis (all P values ≥.06). There were no significant differences in any of the outcomes analyzed with respect to the tumor size (all P values ≥.14) except for a higher occurrence of complications in patients with tumors ≥8 cm versus <8 cm (P = .03). There were no significant differences in any outcomes related to side (left versus right) of the tumor nor BMI (<30 versus ≥30 kg/m²). The overall readmission and conversion rates were both 2.3% and no mortalities were registered.

CONCLUSION

Patient's BMI, tumor side, and size did not demonstrate a negative impact on perioperative and postoperative outcomes of RA. This approach could potentially expand the indications of minimally invasive surgery.