Internal Radiotherapy Combined With Chemo in Colorectal Liver Metastasis
A recent study combined and analyzed data from three trials regarding the use of first-line chemotherapy plus selective internal radiotherapy in patients with colorectal cancer and liver metastases, published in The Lancet Oncology (online August 3, 2017; doi: 10.1016/S1470-2045(17)30457-6).
Previous research suggests that selective internal radiotherapy use in third-line or subsequent therapy for metastatic colorectal cancer provides clinical benefit for patients with liver metastases and liver-dominant disease after chemotherapy. Three recent studies (FOXFIRE, SIRFLOX, and FOXFIRE-Global) randomly evaluated the efficacy of combining first-line chemotherapy with selective internal radiotherapy in this patient population, compared with chemotherapy alone.
Harpreet S Wasan, MRCP, Imperial College Healthcare NHS Trust, Hammersmith Hospital (United Kingdom), and colleagues conducted a combined analysis of the FOXFIRE, SIRFLOX, and FOXFIRE-Global studies to assess for overall survival (OS). In all three trials, chemotherapy-naïve patients with colorectal cancer and liver metastasis who were not suitable for curative resection or ablation were randomly assigned (1:1) to receive either oxaliplatin-based chemotherapy (FOLFOX: leucovorin, fluorouracil, and oxaliplatin) or FOLFOX plus single treatment selective internal radiotherapy concurrent with cycle 1 or 2 of chemotherapy.
Researchers evaluated OS in the intention-to-treat population by using a two-stage meta-analysis of pooled individual patient data. All three trials completed 2 years of follow-up.
A total of 549 patients received FOLFOX alone and 554 patients received FOLFOX plus selective internal radiotherapy. Median follow-up was 43.3 month.
Researchers reported 411 deaths in the FOLFOX cohort (75%) and 433 deaths in the FOLFOX plus selective internal radiotherapy cohort (78%). No significant difference in OS was observed between the two cohorts (HR, 1.04; 95% CI, 0.90-1.19; P = .61). Median survival time in the FOLFOX and FOLFOX plus selective internal radiotherapy cohorts were 23.3 months (95% CI, 21.8-24.7) and 22.6 months (95% CI, 21.0-24.5), respectively.
Additionally, serious adverse events of any grade were reported in 274 (54%) of patients in the FOLFOX plus selective internal radiotherapy cohort, compared with 244 (43%) of those in the FOLFOX cohort.
Results of the study led researchers to conclude that the addition of selective internal radiotherapy to first-line chemotherapy in liver-only and liver-dominant metastatic colorectal cancer does not improve OS and therefore should not be recommended. “To further define the role of selective internal radiotherapy in metastatic colorectal cancer, careful patient selection and studies investigating the role of selective internal radiotherapy as consolidation therapy after chemotherapy are needed,” they wrote.—Zachary Bessette