Selective transarterial radioembolisation of unresectable liver-dominant colorectal cancer refractory to chemotherapy.

Purpose: The target lesion response (according to the Choi criteria), safety and survival following selective or superselective transarterial radioembolisation using yttrium-90-resin microspheres ((90)Y-RE) were evaluated in patients with unresectable, chemotherapy-refractory colorectal cancer liver metastases (mCRC).

Materials And Methods: A prospective case series evaluated 52 consecutive patients with mCRC who were treated at a single centre following a median of 2 lines of chemotherapy.

Results: Nearly half (46.2 %) of the 52 patients had a prior resection of the liver. At baseline, mCRC was limited to the liver (in 56.9 %), liver plus extra-hepatic metastases (23.5 %) or liver plus lung micro-nodules (19.6 %). Disease control rates of target lesions (partial response plus stable disease) at 3 and 6 months post-(90)Y-RE were 59 and 29 %, respectively. Target lesions were sufficiently downsized in two patients for hepatic resection and in one patient for radiofrequency ablation. Median Kaplan-Meier survival was 11.0 months (95 % confidence interval: 8.0-14.0 months) overall and 12.0 months in liver-only disease (±lung micro-nodules). Determinants of prolonged survival were response at 3 months (P = 0.046), ≤5 liver nodules (P = 0.004), single-liver-lobe involvement (P = 0.037), tumour-to-whole liver ratio <25 % (P = 0.021) and absence of extrahepatic metastases (P = 0.045). Adverse events possibly related to the nontarget distribution of (90)Y-RE were grade 1 (90)Y-RE-induced liver disease (n = 1), grade 2 and 3 gastric ulcers (n = 2).

Conclusion: These results confirm the effectiveness and safety of selective (90)Y-RE in patients with chemotherapy-refractory mCRC, showing (90)Y-RE's potential as a bridging therapy to subsequent resection even in this end-stage population.