Search

Background: Adrenal lipid-poor adenomas (LPA) are defined by high unenhanced density (≥ 10 HU), and absolute and relative contrast medium washout > 60% and > 40%, respectively, at computerized tomography (CT). To date, no thorough histopathological characterization has been performed in those frequent lesions (one-third of adrenal adenomas). Our aim was to analyze the histopathological characteristics of adrenal LPA. Methods: Patients with LPA (n= 57) were selected among consecutive subjects referred for an adrenal incidentaloma or ACTH-independent Cushing syndrome. FluoroDeoxyGlucose-Positron Emission Tomography (FDG-PET) was performed in 37 patients. In patients treated by adrenalectomy (n= 17), Weiss score and Lin–Weiss–Bisceglia score (in tumors composed entirely or predominantly of oncocytes) were calculated. Results: Radiological parameters did not differ among patients with ACTH-independent Cushing syndrome (n= 6) and those with adrenal incidentalomas associated with primary aldosteronism (n= 2), autonomous cortisol secretion (n= 14), or non-functioning (n= 35). Patients treated by adrenalectomy had larger tumors (28.9 ± 11.2 vs17.3 ± 8.4 mm,P< 0.001), higher CT unenhanced density (29.1 ± 11.0 vs23.1 ± 9.0 HU, P= 0.043), and FDG-PET adrenal uptake (9.0 ± 6.4 vs4.4 ± 2.3 SUV, P= 0.003) than non-operated ones. Oncocytic features > 75% of the tumor were detected in 12/17 cases (70.6%). Five of those showed borderline-malignant histopathological characteristics by Lin–Weiss–Bisceglia score. Among remaining non-oncocytic tumors, 1/5 had a Weiss score ≥ 3. Overall, 6/17 tumors (35.3%) had borderline-malignant potential. Radiological parameters were similar between patients with benign and borderline-malignant tumors. Conclusions: Adrenal LPA are a heterogeneous group of tumors, mostly composed of oncocytomas. Up to 1/3 of those tumors may have a borderline-malignant potential at histopathology.

Objectives: Pheochromocytomas are rare tumors which can present with heterogeneous secretion profiles, clinical manifestations, and radiologic appearance. Under a histopathological point of view, they can be characterized as more or less aggressive with the Pheochromocytoma of the Adrenal gland Scaled Score (PASS) and the Grading system for Adrenal Pheochromocytoma and Paraganglioma (GAPP) score. The aim of this study is to analyze the texture analysis characteristics of pheochromocytoma and identify whether the texture analysis can yield information aiding in the diagnosis and the characterization of those tumors. Methods: Radiological, biochemical, and histopathological data regarding 30 consecutive patients with histologically confirmed pheochromocytoma were analyzed. Images obtained in the unenhanced, late arterial, venous, and delayed phases were used for the texture analysis. Results: Urinary epinephrine and metanephrine levels showed a significant correlation (R2= 0.946; R2= 699) in the multivariate linear model with texture features, as well as Ki-67 (R2= 0.397), PASS score (R2= 0.182), GAPP score (R2= 0.705), and cellularity showed a significant correlation (R2= 0.389). The cluster analysis based on radiomic features resulted in 2 clusters, with significative differences in terms of systolic and diastolic blood pressure values at the time of diagnosis (p= 0.025), GAPP score (4 vs 6, p= 0.05), histological pattern (1–2, p= 0.039), and comedonecrosis (0% vs 50%, p= 0.013). Conclusion: In conclusion, our study provides the proof of concept for the use of texture analysis on contrast-enhanced CT images as a noninvasive, quantitative tool for helping in the characterization of the clinical, biochemical, and histopathological features of pheochromocytoma.