Canadian Urological Association guideline: Diagnosis, management, and followup of the incidentally discovered adrenal mass

Evaluation of the Adrenal Mass in Urologic Practice

Adrenal masses are commonly encountered as incidental findings in urologic practice. Many of these lesions do not undergo appropriate testing, likely because guidelines have historically been complex and contradictory. However, the workup for the vast majority of these lesions is actually straightforward. Here we present a practical, guidelines-based approach to the workup of adrenal lesions. We focus on distinguishing between benign, nonhormonally active adenomas (which require no further imaging or intervention) from those which are concerning for malignancy or are hormonally active.

Canadian Association of Radiologists Genitourinary Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Genitourinary Expert Panel is made up of physicians from the disciplines of radiology, emergency medicine, family medicine, nephrology, and urology, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 22 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 30 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 65 recommendation statements across the 22 scenarios (2 scenarios point to the CAR Obstetrics and Gynecology Diagnostic Imaging Referral Guideline). This guideline presents the methods of development and the referral recommendations for haematuria, hypertension, renal disease (or failure), renal colic, renal calculi in the absence of acute colic, renal lesion, urinary tract obstruction, urinary tract infection, scrotal mass, or pain, including testicular torsion, adrenal mass, incontinence, urgency, and frequency, chronic pelvic pain, elevated PSA, infertility, and pelvic floor.

Perioperative management of patients with glioblastoma copresenting with pheochromocytoma: illustrative case

BACKGROUND

Undiagnosed pheochromocytoma can present with hemodynamic instability during surgical procedures. Here, the authors discuss a 69-year-old male with isocitrate dehydrogenase (IDH)-wildtype glioblastoma copresenting with undiagnosed pheochromocytoma, which, to the authors' knowledge, is the second reported case in the literature.

OBSERVATIONS

The patient presented to the emergency department with a 1-month history of coordination difficulties, progressive morning headache, and mild left-side weakness. Imaging showed a 5-cm peripherally enhancing intra-axial right parietal mass with surrounding vasogenic edema. Intraoperatively, the patient had significant uncontrollable hypertension up to 240/120 mm Hg, and the operation was promptly aborted. Contrast-enhanced computed tomography imaging of the chest, abdomen, and pelvis identified a 4.9-cm left adrenal mass of indeterminant etiology. Endocrinology diagnosed the incidentaloma as a pheochromocytoma, initiating alpha blockade followed by beta blockade, and the urology service performed a laparoscopic adrenalectomy after patient stabilization. The neurosurgery service removed the intra-axial brain lesion 2 days after adrenalectomy, which was diagnosed as IDH-wildtype glioblastoma. The patient was discharged home after 6 days in stable condition.

LESSONS

This case highlights the importance of preoperative screening for pheochromocytoma in neurosurgical patients with adrenal incidentalomas, especially in incidentalomas > 4 cm, even without high clinical suspicion. https://thejns.org/doi/10.3171/CASE24374.

Dielectric characterisation of human adrenal glands and adrenal tumours for the development of microwave ablation technologies for hypertension treatment

Adrenal gland-induced hypertension results from underlying adrenal gland disorders including Conn's syndrome, Cushing's syndrome, and Pheochromocytoma. These adrenal disorders are a risk for cardiovascular and renal morbidity and mortality. Clinically, treatment for adrenal gland-induced hypertension involves a pharmaceutical or surgical approach. The former presents very significant side effects whereas the latter can be ineffective in cases where the adrenal disorder reoccurs in the remaining contralateral adrenal gland. Due to the limitations of existing treatment methods, minimally invasive treatment options like microwave ablation (MWA) have received significant attention for treating adrenal gland disorders. A precise comprehension of the dielectric properties of human adrenal glands will help to tailor energy delivery for MWA therapy, thus offering the potential to optimise treatments and minimise damage to surrounding tissues. This study reports the ex vivo dielectric properties of human adrenal glands, including the cortex, medulla, capsule, and tumours, based on the data obtained from four patients (diagnosed with Conn's syndrome, Cushing's syndrome, and Pheochromocytoma) who underwent unilateral adrenalectomy at the University Hospital Galway, Ireland. An open-ended coaxial probe measurement technique was used to measure the dielectric properties for a frequency range of 0.5-8.5 GHz. The dielectric properties were fitted using a two-pole Debye model, and a weighted least squares method was employed to optimise the model parameters. Moreover, the dielectric properties of adrenal tissues and tumours were compared across frequencies commonly used in MWA, including 915 MHz, 2.45 GHz, and 5.8 GHz. The study found that the dielectric properties of adrenal tumours were influenced by the presence of lipid-rich adenomas, and the dielectric properties of Cushing's syndrome tumour were lowest in comparison to the tumours in patients diagnosed with Conn's syndrome and Pheochromocytoma. Furthermore, a notable difference was observed in the dielectric properties of the medulla and cortex among patients diagnosed with Conn's syndrome, Cushing's syndrome, and Pheochromocytoma. These findings have significant implications for the diagnosis and treatment of adrenal tumours, including the optimisation of MWA therapy for precise ablation of adrenal masses.

Performance of CT With Adrenal-Washout Protocol in Heterogeneous Adrenal Nodules: A Multiinstitutional Study

BACKGROUND. CT with adrenal-washout protocol (hereafter, adrenal-protocol CT) is commonly performed to distinguish adrenal adenomas from other adrenal tumors. However, the technique's utility among heterogeneous nodules is not well established, and the optimal method for placing ROIs in heterogeneous nodules is not clearly defined. OBJECTIVE. The purpose of our study was to determine the diagnostic performance of adrenal-protocol CT to distinguish adenomas from nonadenomas among heterogeneous adrenal nodules and to compare this performance among different methods for ROI placement. METHODS. This retrospective study included 164 patients (mean age, 59.1 years; 61 men, 103 women) with a total of 164 heterogeneous adrenal nodules evaluated using adrenal-protocol CT at seven institutions. All nodules had an available pathologic reference standard. A single investigator at each institution evaluated the CT images. ROIs were placed on portal venous phase images using four ROI methods: standard ROI, which refers to a single large ROI in the nodule's center; high ROI, a single ROI on the nodule's highest-attenuation area; low ROI, a single ROI the on nodule's lowest-attenuation area; and average ROI, the mean of the three ROIs on the nodule's superior, middle, and inferior thirds using the approach for the standard ROI. ROIs were then placed in identical locations on unenhanced and delayed phase images. Absolute washout was determined for all methods. RESULTS. The nodules comprised 82 adenomas and 82 nonadenomas (36 pheochromocytomas, 20 metastases, 12 adrenocortical carcinomas, and 14 nodules with other pathologies). The mean nodule size was 4.5 ± 2.8 (SD) cm (range, 1.6-23.0 cm). Unenhanced CT attenuation of 10 HU or less exhibited sensitivity and specificity for adenoma of 22.0% and 96.3% for standard-ROI, 11.0% and 98.8% for high-ROI, 58.5% and 84.1% for low-ROI, and 30.5% and 97.6% for average-ROI methods. Adrenal-protocol CT overall (unenhanced attenuation ≤ 10 HU or absolute washout of ≥ 60%) exhibited sensitivity and specificity for adenoma of 57.3% and 84.1% for the standard-ROI method, 63.4% and 51.2% for the high-ROI method, 68.3% and 62.2% for the low-ROI method, and 59.8% and 85.4% for the average-ROI method. CONCLUSION. Adrenal-protocol CT has poor diagnostic performance for distinguishing adenomas from nonadenomas among heterogeneous adrenal nodules regardless of the method used for ROI placement. CLINICAL IMPACT. Adrenal-protocol CT has limited utility in the evaluation of heterogeneous adrenal nodules.

Clinical indications, safety, and effectiveness of percutaneous image-guided adrenal mass biopsy: an 8-year retrospective analysis in 160 patients

PURPOSE

To assess indications, safety, and effectiveness of percutaneous adrenal mass biopsy in contemporary practice.

METHODS

This institutional review board-approved, retrospective study included all patients undergoing percutaneous image-guided adrenal mass biopsies at an academic health system from January 6, 2015, to January 6, 2023. Patient demographics, biopsy indications, mass size, laboratory data, pathology results, and complications were recorded. Final diagnoses were based on pathology or ≥ 1 year of imaging follow-up when biopsy specimens did not yield malignant tissue. Test performance calculations excluded repeat biopsies. Continuous variables were compared with Student's t test, dichotomous variables with chi-squared test.

RESULTS

A total of 160 patients underwent 186 biopsies. Biopsies were indicated to diagnose metastatic disease (139/186; 74.7%), for oncologic research only (27/186; 14.5%), diagnose metastatic disease and oncologic research (15/186; 8%), and diagnose an incidental adrenal mass (5/186; 2.7%). Biopsy specimens were diagnostic in 154 patients (96.3%) and non-diagnostic in 6 (3.8%). Diagnostic biopsies yielded malignant tissue (n = 136), benign adrenal tissue (n = 12), and benign adrenal neoplasms (n = 6) with sensitivity = 98.6% (136/138), specificity = 100% (16/16), positive predictive value = 100% (136/136), and negative predictive value = 88.9% (16/18). Adverse events followed 11/186 procedures (5.9%) and most minor (7/11, 63.6%). The adverse event rate was similar whether tissue was obtained for clinical or research purposes (10/144; 6.9% vs. 1/42; 2.4%, p = 0.27), despite more specimens obtained for research (5.8 vs. 3.7, p < 0.001).

CONCLUSION

Percutaneous adrenal mass biopsy is safe, accurate, and utilized almost exclusively to diagnose metastatic disease or for oncologic research. The negative predictive value is high when diagnostic tissue samples are obtained. Obtaining specimens for research does not increase adverse event risk.