Jessica Heard

and 4 more

Background: The role and benefit of yittrium-90 (Y-90) remain in question amongst patients with metastatic chemo-refractory colorectal liver metastases (CRLM). We aim to report a complete experience and outcomes following lobar, segmental, combination administration, and repeated Y-90 radioembolizations utilizing a minimal prescribed dose in the treatment of CRLM. Methods and Results: This is a retrospective analysis of all patients who underwent Y-90 radioembolization of CRLM at a single institution. Tumor response was evaluated using a modified RECIST criteria 2-6 months post-radioembolization. Progression-free survival (PFS) was the primary outcome of interest. Tumor response, conversion to resectable disease, and overall survival (OS) were analyzed as a secondary outcomes. 4 rectal and 7 colonic adenocarcinoma CRLM patients with significant previous systemic therapy exposure were included. The median tumor number and size was 3 and 4.0 cm, respectively. 7 segmental and 12 lobar radioembolizations were performed (range 1-6 per patient) with a mean administered activity of 22.1 mCi. Tumor regression occurred in 71.4% of cases with 4 complete radiographic responses. The median hepatic PFS was 5.5 months. The median OS from the time of primary cancer diagnosis and initial Y-90 was 3.2 and 1.2 years, respectively. 18% of initially unresectable patients were converted to surgically resectable. Conclusions: Y-90 results in reliable tumor regression and repeated radioembolizations are safe when conservative doses are utilized in a multidisciplinary setting. This study supports the ‘neoadjuvant’ use of Y-90 to allow for the conversion of borderline resectable patients to resectable. The results suggest that Y-90 maybe associated with an OS benefit in chem-refractory CRLM patients.