38P Venous thromboembolism in patients with adrenocortical carcinoma: A multicentre retrospective study

Adrenocortical carcinoma (ACC) patients have a high chance of developing venous thromboembolism (VTE) due to numerous risk factors that include malignancy, hormonal excess, surgery, and immobility. The incidence of VTE in these patients is unclear. In this multicentre retrospective study, we evaluated ACC patients (pts) treated in 6 Referral Centres from January 2005 to September 2023. The study aimed to assess the prevalence of VTE in ACC pts, describe their characteristics and identify potential prognostic factors. Out of 1597 ACC pts, 124 (8%) presented at least one VTE, of whom 45 (36%) developed pulmonary embolism, 52 (42%) deep venous thrombosis and 27 (22%) both. Among pro-thrombotic risk factors, 28 (23%) patients were current or former smokers, 36 (29%) had a central venous catheter, 10 (8%) presented familiar history or genetic predisposition. Thirty-four (27%) pts presented intra vena cava or renal vein tumor thrombus at ACC diagnosis. The majority of patients underwent adrenalectomy (86%), of whom 17 (14%) did not attained a complete resection. The median age at first VTE appearance was 54 years, thirty-one (25%) patients had cortisol overproduction at VTE diagnosis and 109 (88%) presented with III or IV ENSAT stage ACC. One-hundred eighteen (95%) pts developed VTE after at least 3 months since ACC diagnosis. Nine (7%) pts required urgent medication and 57 (46%) needed lifelong anti-coagulant treatment. Median OS was 45 months, at multivariate analysis the presence of tumor thrombus (HR 1.78, CI: 1.05-3.04, p=0.032) and surgery on primary ACC (HR 0.067, CI: 0.02-0.16, p ≤ 0.001) confirmed their prognostic role. ACC patients are at moderate risk of developing VTE, which requires proper management. The presence of thrombosis at initial diagnosis has a negative impact on prognosis.