Intra-hepatic cholangiocarcinoma--frequency and demographic patterns: thirty-year data from the M.D. Anderson Cancer Center.

PURPOSE: Recent reports have shown an increase in frequency of intra-hepatic cholangiocarcinoma (IHC) with a stable or decreased frequency of extra-hepatic cholangiocarcinoma (EHC). However, data on the demographic patterns associated with this change are limited. We analyzed cases of cholangiocarcinoma (CC) with aim to study frequency and demographic patterns over time of IHC and EHC.

METHODS: Data were collected from MD Anderson Cancer Center Tumor Registry on CC (1978-2007) and stratified on age (<50, 50-59, 60-69, and ≥70 years), gender, ethnicity (Caucasian, African-American, Hispanic, and Other), time (1978-1987, 1988-1997, 1998-2007), and diagnosis (IHC and EHC). Chi-square tests and logistic regression were used for statistics.

RESULTS: Of 1,061 CC (445 IHC), proportion of IHC increased from 30% in 1978-1998 to 48% during 1998-2007 (P < 0.0001). Compared to EHC, IHC occurred more frequently in relatively young (age < 60 years) (21 and 27% vs. 15 and 23% in 0-49 years and 50-59 years, respectively; P = 0.003) and females (48 vs. 42%, P = 0.03). Ethnic distribution was similar. There was significant (P = 0.019) interaction between age and gender using logistic regression analysis.

CONCLUSIONS: Increase in frequency of IHC occurred over time and is more frequently observed among females <60 years. These data may have implications in understanding pathogenesis of IHC.