SAT-375 Adrenal Incidentaloma: Results of 12 Year's Follow-Up at a Tertiary-Referral Hospital in Havana, Cuba

Most adrenal incidentalomas (AI) consists of benign, non-functional tumours. During their natural development, tumour growth and change in previous hormonal functional status may occur. AIM: to analyse modifications in tumour size and cortisol secretion in patients with AI during follow-up. METHODS: Among a group of one-hundred patients diagnosed for AI between January 2006 and January 2018, fifty-four were sent to AI follow-up protocol. Periodical clinical evaluation, CT scans and hormonal assessment were performed. Regarding tumour growth, patients were divided in Growing Group (GG) and Non-Growing Group (Non-GG). Regarding cortisol secretion, patients were divided in Disorders of Cortisol-Secretion Group (DCSG) and Non-Disorders of Cortisol-Secretion Group (Non-DCSG). Statistical analysis were applied to test the association between selected variables and those groups. P values <0.05 were considered significant. A survival study (Kaplan-Mayer curve) to estimate both growth and hormonal dysfunction probabilities during follow-up was performed. RESULTS: 54 patients (56 tumours: 2 patients with bilateral myelolipomas); 45 females, 9 males. Mean follow-up period: 5,1 years. During follow-up, disorders in cortisol secretion (DCS) were found in 7 patients (7%): 4 subclinical hypercortisolism and 3 overt Cushing’s Syndrome. An increase in tumour size > 1cm was found in 4 tumours (7,1%). An increase between 0,5-1 cm was reported in 5 tumours (8,9%). Decreasing size was reported in 10 masses (17,9%), including disappearance of 2 masses. 58,9% of tumours remained the same size. Regarding growth, association was found only between tumour growth and DCS (GG with DCS: 33,3%, Non-GG with DCS: 7,1%; p=0,04). Regarding evolutionary DCS, association was found for 3 variables: <1-year follow-up period (DCS-G with <1-year follow-up: 42,9%; Non-DCSG <1-year follow-up: 2,1%; p=0,001), mean diameter (DCS-G: 4,6cm, Non-DCSG: 3,2cm; p=0,01), and decreased DHEA-S (DCS-G with decreased DHEA-S: 66,7%, Non-DCSG with decreased DHEA-S: 20,0%; p=0,031). 10 patients underwent surgery after follow-up: 4 functioning adenomas, 1 non-functioning adenoma, 1 myelolipoma and 4 tumours initially diagnosed for benign, non-functioning adenomas, in which significant growth occurred, resulting in 1 neurilemoma, 2 silent pheochromocytomas and 1 granulomatous adrenalytis. According to survival study (Kaplan-Mayer Curve), the estimated major probabilities for developing growth and DCS take place before two-years of evolution. No malignancy was found during follow-up. CONCLUSION: During follow-up, AI have a low probability for growth or for developing cortisol-secreting disorders, mostly before two-years-follow-up period.