Abstract No. 28 Chemoembolization (TACE) with High-Dose 1,3-Bis-(2-Chloroethyl)-1-Nitrosourea (BCNU) for First-Line Treatment of Limited Uveal Melanoma Hepatic Metastases

This is the authors' abstract. We don't add key points for this paper.

To report early results of a Phase II trial using high-dose BCNU TACE for treatment-naïve metastatic uveal melanoma (MUM) patients with limited hepatic tumor burden. Fifteen patients (6 men; median age, 63; range, 39-84) with < 50% hepatic tumor burden were treated with lobar BCNU (300 mg) TACE every 4 weeks (±7 days) for a minimum of 4 procedures (median 4; range, 4-6) from October 2021 - March 2023. Extrahepatic disease except for osseous metastases excluded patients from trial enrollment. Patients were treated until maximum clinical benefit, progression of disease (PD), or development of adverse events (AE). Tumor response (RECIST 1.1) and extrahepatic disease were assessed using CT and MRI. Treatment breaks were provided for patients with disease control (partial response [PR] + stable disease [SD]) to limit toxicities. Toxicities were determined using CTCAE version 5.0. TACE off-trial was permitted if PD occurred during treatment breaks. Overall survival (OS), progression-free survival from liver (PFS-L), and systemic (PSF-S) metastases were evaluated. OS ranged from 6.3 - 21.3 months with 8 surviving patients. Treatment response included PR=5; SD=9 and PD=1 for a disease control rate of 93.3%. Median PFS-L was 7.5 months (range, 3.3 - 21.3 months). Patients developed new hepatic tumors (n=10), progression of target-lesions (n=1), or both (n=1). PD occurred in 9/12 patients on treatment break. 10/15 patients developed extrahepatic metastases. Median PFS-S was 8.0 months (range, 1.8 - 21.3 months). Treatment-related grade 3 AEs included hypertension (n=4), pain (n=5), thrombocytopenia (n=1), and an infected biloma. Transient grade 3 and 4 liver enzyme elevation occurred in 6 patients. TACE is typically reserved for patients presenting with bulky hepatic metastases or as salvage therapy. Initial results of this ongoing Phase II trial demonstrate safety and efficacy of high-dose BCNU TACE as first-line treatment for limited uveal melanoma hepatic metastases. PD commonly occurred during treatment breaks, as expected. Future trials combining BCNU TACE with systemic therapy are warranted to assess their effectiveness in preventing or delaying the development of extrahepatic disease.