17. TUMOR SIZE IN ADRENAL TUMORS. SIGNIFICANCE IN THE INDICATION FOR ADRENALECTOMY AND SURGICAL OUTCOMES

Abstract

Abstract Introduction This study aims to assess the relevance of tumour size in adrenal tumours concerning the estimation of malignancy risk and its impact on the outcomes of adrenalectomy. Methods Histological results and surgical outcomes were assessed in a retrospective cohort of patients without a history of active extra-adrenal malignancy but with adrenal tumours. The study included individuals who underwent surgery at a third-level hospital between 2010 and 2020. Results Of 131 patients with adrenal tumours who underwent adrenalectomy, 76 (58.0%) had adrenal masses measuring ≥40 mm; 47 were >50 mm and 28 >60 mm. The final diagnosis was adrenocortical carcinoma (ACC) in 7 patients, pheochromocytoma in 35, and benign lesions in the remaining. All patients with ACC had adrenal masses > 50 mm, with Hounsfield units >40 and low lipidic content in the CT. The risk of ACC and pheochromocytoma increased as tumour size did. The diagnostic accuracy of tumour size was quite good for the prediction of ACC (AUC-ROC 0.883). Nevertheless, when only adrenal tumours with HU <40 were considered, the risk of ACC was 0% independent of tumour size. For pheochromocytomas, the risk was of 8.6% independent of tumour size for lesions with <20HU. The risk of intraoperative and postoperative complications was independent of tumour size. Conclusion The risk of malignancy and pheochromocytoma increased with tumor size. However, in pre-surgical assessments of malignancy risk, considerations should extend beyond tumor size to include lipidic content and other radiological features. The risk of complications was independent of tumour size, but hospital stay was longer in patients with complication or open approach.