Computed tomography (CT) scan identified necrosis, but is it a reliable single parameter for discerning between malignant and benign adrenocortical tumors?

Abstract

Background: Adrenocortical carcinoma is a rare malignant tumor with a poor prognosis. Discernment of adrenocortical carcinoma in an adrenal mass through imaging studies is paramount for early surgical treatment. Recently, necrosis has been proposed as a single morphological parameter for adrenocortical carcinoma diagnosis. The aim of this study was to analyze the measures of diagnostic efficiency of necrosis and the different computed tomography-scan features related to adrenocortical carcinoma diagnosis.

Methods: We conducted a case-control study of patients surgically treated for an adrenal mass with histopathological report consistent with adrenocortical carcinoma (cases) and adrenocortical adenoma (control patients) between 1987 and 2019. Radiological features on computed tomography scan were collected. Bivariate and multivariate statistical analyses were performed for the different imaging features. The measures of diagnostic efficiency for each feature were calculated. Concordance analysis between image-detected and histopathological-identified necrosis was performed.

Results: Eighteen adrenocortical carcinoma and 41 adrenocortical adenomas were included. Differences between adrenocortical carcinoma and adrenocortical adenoma were found regarding heterogeneity (odds ratio 4.53, 95% confidence interval 2.3-8.9; P < .0001), tumor size ≥4 cm (odds ratio 3.5, 95% confidence interval 2.05-6.14; P < .0001), and attenuation index ≥10 Hounsfield units (odds ratio 1.9, 95% confidence interval 1.3-2.6; P = .001). Necrosis was the most important imaging feature significantly associated with adrenocortical carcinoma (odds ratio 35, 95% confidence interval 5.1-241.6; P < .0001), present in all adrenocortical carcinoma cases. After measures of diagnostic efficiency calculation, necrosis had the highest diagnostic accuracy (98%). Cohen's kappa for concordance between image-detected and histopathological-identified necrosis was 90.4% (P < .0001).

Conclusion: Computed tomography scan-detected necrosis is a reliable radiological feature to discern adrenocortical carcinoma from adrenocortical adenomas.