41Cholangiocarcinoma incidence in the United States: Analysis of 121,732,956 adult individuals
Valerie Gunchick, Amanda Nottke, David H Howard, Ruth M Pfeiffer, Jill Koshiol, Juan W ValleAbstract
Background and objectives
Cholangiocarcinoma (CCA) is a rare cancer with incidence that varies by ancestry and is reportedly increasing. Accurate incidence and prevalence statistics calculated from recent data are essential for characterizing the present burden of disease to enable adequate allocation of resources towards early identification and diagnosis. CCA incidence in the United States (US) has been reported as 2-5% per 100,000 person-years when analyzed in cancer registries that included data up to 2018. These studies also report an increasing incidence, as much as 148.8% from 2001 to 2017 for intrahepatic CCA. Herein, we evaluate recent claims data in the US to quantify current CCA incidence, supporting up-to-date characterization of CCA burden.
Methods
The Komodo Health Healthcare Map includes approximately 330 million individuals’ insurance claims from Medicare, Medicaid, and commercial insurance companies in the US. We evaluated adults who were continuously enrolled (CE) with an insurance plan for at least 180 days from January 1, 2017, through Dec 31st, 2024. We identified incident CCA cases with two definitions. The first required ≥1 inpatient claim and the second additionally included ≥2 outpatient claims assigned an International Classification of Disease 10th edition code describing intrahepatic CCA (C22.1), extrahepatic CCA (C24.0), or unspecified/overlapping CCA (C24.8 and C24.9). Crude incidence was calculated as the number of CCA cases divided by the number of person-years with Poisson exact confidence intervals (CIs). The incidence rates were sex and age-adjusted to the 2020 US Census population, and Fay-Feuer gamma confidence intervals were estimated. RStudio 2025.09.1 and the R package, epitools were used for analyses.
Results
In total, we evaluated 121,732,956 adults who met CE requirements, encompassing 442,139,047 person-years. Most (54.6%) were female and White (43.3%) with a median [minimum, maximum; 25th, 75th percentile] age of enrollment of 45 [18, 89; 31, 60] and a median CE duration of 2.8 years [0.5, 15.7; 1.3, 5.3]. We identified 35,777 incident CCA cases with ≥1 inpatient claim and/or ≥2 outpatient claims, of which most were male (51.2%) and White (62.4%), with a median age of enrollment of 68 [18, 88; 61, 75], a median CE duration of 4.7 years [0.5, 15.9; 2.8, 7.2], and a median age of CCA diagnosis of 72 [19, 89; 65, 80]. The preliminary crude incidence rate (95% CI) was 8.10 (8.01-8.18) per 100,000 person-years (ppy), and the age-sex-adjusted rate was 6.96 (6.89-7.03) ppy. We identified 11,178 CCA cases with ≥1 inpatient claim with similar patient characteristics (Table 1). The preliminary crude incidence rate (95% CI) for ≥1 inpatient CCA claim was 2.53 (2.48-2.58) ppy, and the age-sex-adjusted rate was 2.15 (2.11-2.19) ppy. We will further evaluate incidence by sex, race and ethnicity, and insurance type, in addition to overall prevalence, annual incidence, annual prevalence, and CCA subtypes (intrahepatic, extrahepatic, unspecified/overlapping) to ensure robust results describing current CCA burden.
Conclusion
We analyzed insurance claims data that included approximately one-third of the US through from 2017 to 2024. We observed age-sex-standardized incidence rates ranging from 2.15 (2.11-2.19) ppy, for patients with ≥1 inpatient claim, to 6.96 (6.89-7.03) ppy, for patients with ≥1 inpatient claim and/or ≥2 outpatient claims. This estimate is higher than previously reported, following previous reports of increasing incidence, and suggests that CCA incidence may be continuing to increase.