LAUSR

To evaluate the clinical utility of bland arterial embolization using microspheres in patients with hypervascular liver metastases refractory to standard treatments. Primary endpoints of this prospective single-arm non-comparative study were objective response and disease control rates (ORR and DCR), based on the modified Response Evaluation Criteria in Solid Tumors at 4 weeks after embolization. Secondary endpoints were ORR according to primary tumor, overall survival, progression-free survival (PFS), and safety. Twenty-five patients with a median age of 66 years (range, 40–95 years) were enrolled in this study. The median maximum diameter of liver metastasis was 3.7 cm (range, 2.0–15.2 cm). Primary lesions were colorectal cancer in 12 patients (48%, 12/25), other cancer in 7 (28%, 7/25), neuroendocrine tumor in 4 (16%, 4/25), and sarcoma in 2 (8%, 2/25). ORR and DCR were 52% (13/25) and 72% (18/25) in all patients, 42% (5/12) and 75% (9/12) in colorectal cancer patients, and 62% (8/13) and 69% (9/13) in other malignant tumor patients (p = 0.43, p > 0.99). Median survival time was 19 months in all patients, 19 months in colorectal cancer patients, and 8 months (p = 0.16) in other malignant tumor patients. Median PFS time was 4 months in all patients, 4 months in colorectal cancer patients, and 6 months (p = 0.0085) in other malignant tumor patients. There were no grade-3 or -4 adverse events. Microsphere embolization appears to be an effective and safe treatment for hypervascular liver metastases refractory to standard treatments.