7960 Clinical Outcomes of Image-Guided Therapies In Patients With Adrenocortical Carcinoma: A Tertiary Referral Center Retrospective Study

Abstract Disclosure: B. Chahla: None. K. Pal: None. V. Balderrama Brondani: None. F. Yaylaci Mert: None. M. Campbell: None. R. Sheth: None. M.A. Habra: None. Background: Image-guided therapies (IGTs) such as cryoablation or embolization are commonly used in oncology, but their role in adrenocortical carcinoma (ACC) is not well-defined. Materials and Methods: A retrospective review of ACC patients treated with IGTs. We assessed time to next line of systemic therapy, disease control rate (DCR), local tumor progression-free survival (LTPFS), and complications of IGTs.Treatment efficacy was assessed based on RECIST v1.1. Complications were categorized based on the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Results: The study cohort included 26 patients (median age 56 years [range 38-76]; n=18 female) who had 51 IGT sessions to treat 86 lesions. The median Ki-67 is 20 (range 2-79), and median Weiss score is 6 (range 3-9). Seventeen patients received systemic therapy including mitotane, chemotherapy, immunotherapy, and other treatments prior to the first IGT and 10 patients received systemic therapy concurrently with first IGT. IGT modalities included cryoablation (n = 49), microwave ablation (n = 21), combined microwave and bland transarterial embolization (n = 8), bland transarterial embolization alone (n = 3), radioembolization (n = 3), and radiofrequency ablation (n = 2). Treated sites included the liver (n=37), intraperitoneal (n=11), adrenalectomy bed (n=10), lung (n=6), lymph nodes (n=6), retroperitoneal soft tissue (n=6) and other soft tissues (n=10). The median largest pre-IGT anteroposterior tumor dimension was 2.3 cm (range 0.5-8.6). DCR was 81.4% (70 out of 86), of which 66.3% of tumors showed complete response, 18.6% showed progressive disease, 8.1% showed partial response, and 7.0% showed stable disease. LTPFS rates were 73% and 63% at 1 and 2 years, respectively. Fourteen lesions needed re-ablation. Ten patients did not require systemic therapy while 16 patients (61.5%) received new systemic therapy following IGT, with a median time from first IGT to systemic therapy of 12.5 months (95% CI: 8.6 months- upper limit not reached). There was 1 reported CTCAE grade 3 adverse event (biloma) following IGT. Conclusion: IGT use in properly selected ACC lesions is safe and associated with prolonged disease control and delay in the need for systemic therapy. Presentation: 6/2/2024