Disparities in Care Access to Liver-Directed Therapy Among Medicare Beneficiaries with Colorectal Cancer Liver Metastasis

Abstract

Background: Liver-directed therapies (LDT) are important components of the multidisciplinary care of patients with colorectal cancer liver metastases (CRCLM) that contribute to improved long-term outcomes. Factors associated with receipt of LDT are poorly understood.

Patients and methods: Patients > 65 years old diagnosed with CRCLM were identified within the Medicare Standard Analytic File (2013-2017). Patients with extrahepatic metastatic disease were excluded. Mixed-effects analyses were used to assess patient factors associated with the primary outcome of LDT, defined as hepatectomy, ablation, and/or hepatic artery infusion chemotherapy (HAIC), as well as the secondary outcome of hepatectomy.

Results: Among 23,484 patients with isolated CRCLM, only 2004 (8.5%) received LDT, although resectability status could not be determined for the entire cohort. Among patients who received LDT, 61.7% underwent hepatectomy alone, 28.1% received ablation alone, 8.5% underwent hepatectomy and ablation, and 1.8% received HAIC either alone (0.8%) or in combination with hepatectomy and/or ablation (0.9%). Patient factors independently associated with lower odds of LDT included older age, female sex, Black race, greater comorbidity burden, higher social vulnerability index, primary rectal cancer, synchronous liver metastasis, and further distance from a high-volume liver surgery center (p < 0.05). Results were similar for receipt of hepatectomy.

Conclusions: Despite the well-accepted role of LDT for CRCLM, only a small proportion of Medicare beneficiaries with CRCLM receive LDT. Increasing access to specialized centers with expertise in LDT, particularly for Black patients, female patients, and those with higher levels of social vulnerability or long travel distances, may improve outcomes for patients with CRCLM.