OBJECTIVES

: Liver cancer has one of the lowest five-year survival rates and fastest growing incidence rates among all cancer types. Radiation therapy is an effective treatment for liver cancer. This study examined the characteristics of liver cancer patients who received vs. did not receive radiation therapies to inform clinical development of new therapies.

METHODS

: We identified adult patients with a diagnosis of primary liver and/or intrahepatic bile duct cancer during 2011-2019 through a data partnership with Mercy Technology Services, the IT arm of St. Louis-based Mercy, a large US Integrated Delivery Network. The index date was the date of the first occurrence of diagnosis of liver and/or intrahepatic bile duct cancer. Demographics and clinical characteristics were assessed in the 90-day pre-index baseline period and treatments were assessed on or after the index date. We performed descriptive analysis to compare the characteristics of patients who received vs. did not receive radiation therapies.

RESULTS

: We identified 551 patients with primary liver and/or intrahepatic bile duct cancer who met the inclusion criteria; among them, 61 patients (11%) received radiation therapy. The majority (56%) of patients who received radiation therapy had trans-arterial radioembolization (TARE) with yttrium-90 as the first radiation therapy, followed by image-guided radiation therapy, external beam and brachytherapy. Compared to patients who did not received radiation therapies, a smaller percentage of patients receiving radiation therapies had cirrhosis (21% vs. 26%) or received surgical treatments (hepatectomy or liver transplant) (5% vs. 10%). TARE was also the major radiation therapy among patients with cirrhosis (85%).

CONCLUSIONS

: A small proportion of primary liver cancer patients received radiation therapies. TARE was the main radiation therapy choice for primary liver cancer. Predictors of receiving radiation therapies (including tumor characteristics and liver function), longitudinal time course of clinical chemistry (e.g. platelets) and clinical outcomes (e.g. survival) will be evaluated in future studies.