Global practice patterns and outcomes for metastatic uveal melanoma treated regionally versus systemically.

e23324 Background: Due to the hepatotropic pattern of metastasis in uveal melanoma (UM), liver directed therapies (LDT) are commonly used for the treatment of advanced disease. The PUMMA meta-analysis (Khoja et al, 2019) assessed patients (pts) with metastatic UM (mUM) treated on trials conducted from 2000-2016 and suggested improved outcomes for those treated with LDT. Methods: Using data from 7 centers in the US, Canada, the UK and Australia collected between as part of the Ocular Melanoma Natural History (OMNi) study, we assessed this finding in a more contemporary dataset and investigated potential global variations in practice patterns. Analysis was performed on data entered as of May 2024. Results: Of 985 pts enrolled, 283 developed mUM and received at least 1 line of treatment (tx; 77-US; 160-Canada; 30-UK; 16-Australia). 164 received regional (R) tx (LDT, surgery, radiation; 41% US pts, 35% Canadian pts, 46% UK pts, 55% Australian pts), with 130 treated in the first-line (1L) setting. 212 received systemic (S) tx (51% US pts, 55% Canadian pts, 51% UK pts, 55% Australian pts), with 137 treated in the 1L setting. Concurrent (C; any R tx delivered while a S tx was ongoing) was administered in 50 patients (18% US pts, 10% of Canada pts, 3% UK, pts 5% Australian pts), with 16 treated in the 1L setting. At the time of 1L tx, median age was 63 (range, 25-92), 62 (range, 24-88), and 64 (range, 42-83) years for those treated with S, R, and C tx, respectively. 47%, 50% and 25% were female of those treated with S, R, and C tx, respectively. Mean diameter of the largest tumor lesion and percentage of cases with stage M1b/c disease at time of 1L tx were 1.5cm and 20%, 1.1cm and 19%, and 0.6 cm and 0% for those treated with S, R or C tx, respectively. There was no significant difference in proportion of patients with liver-only disease who received 1L S or R/C tx (61 vs 62%, respectively). Median overall survival (OS) was 32, 24 and 32 months for those treated with S, R or C tx, respectively, with no significant difference observed across groups (p = 0.09). Conclusions: The use of C tx was more common in the US and Canadian centers when compared with those in the UK and Australia. Patient and tumor characteristics were similar between those treated with 1L S and R therapies, with no difference in OS observed in this dataset based upon initial tx strategy. Clinical trial information: NCT04588662 . Therapy Pts Receiving 1L Systemic Therapy (n = 137) Pts Receiving 1L Regional Therapy (n = 130) Pts Receiving 1L Concurrent Therapy (n = 16) Systemic Regional Checkpoint Blockade 104 (76%) n/a 10 (62%) n/a Targeted Therapy 22 (16%) n/a 6 (38%) n/a Other Systemic Therapy 11 (8%) n/a 0 (0%) n/a Surgery or Radiofrequency Ablation n/a 62 (48%) n/a 3 (18%) Radiotherapy n/a 22 (17%) n/a 4 (25%) Other Liver Directed Therapy n/a 34 (26%) n/a 6 (38%) Radioembolization or Chemoembolization n/a 9 (7%) n/a 2 (12%) Percutaneous Hepatic Perfusion n/a 3 (2%) n/a 1 (6%)