Colorectal Liver Metastasis Survival After Yittrium-90
Radioembolization: A Complete 3-year Experience
Abstract
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.