# Primary Biliary Tract Cancers in Golestan, Iran: 13-Year Experience of Golestan Population-Based Cancer Registry

## TL;DR

This study examines the incidence trends of biliary tract cancer in Golestan, Iran, over 13 years, highlighting gender and age differences.

## Contribution

The study provides a detailed 13-year analysis of biliary tract cancer epidemiology in a specific high-risk Iranian population.

## Key findings

- Males showed a rising incidence trend of biliary tract cancer, while females showed a decreasing trend.
- Age-specific incidence rates increased for both genders starting at age 45, with males showing a significant rise in the 75-79 age group.
- Urban residence, male gender, and older age were identified as key risk factors for biliary tract cancer in this region.

## Abstract

Epidemiological research on the high-risk population might be helpful in early detection and prevention of biliary tract malignancies. This study assesses the prevalence of biliary tract cancer (BTC) in the Golestan province, northeastern Iran, between 2004 and 2016.

The current study used information from the Golestan Population-based Cancer Registry (GPCR) to access the epidemiology of BTC across a 13-year period while taking into account temporal and geographic differences. The number of cases, crude rates, age-standardized incidence rates (ASRs) per 100,000 person-years, average annual percent change (AAPC), age-specific incidence rates, and 95% confidence intervals (CI) were reported for each year with respect to gender and place of residence.

Totally, 224 instances of BTC overall (54% of whom were females) were reported throughout the research period. The ASR of BTC was 1.7 (95% CI: 1.4‒2) for females and 1.4 (95% CI: 1.1‒1.6) for men, respectively. Males exhibited a growing time trend in incidence (AAPC: 7.18; CI: 0.06‒14.81; P-value:0.048), whereas females had a decreasing trend (AAPC: 0.82; CI: -5.94‒4.57; P-value: 0.740). Both sexes saw an increase in age-specific incidence rates starting at the age of 45; however, males experienced a significant increase in incidence in the age group of 75 to 79 while the female rates grew steadily.

The focus for cancer control in this region may be given to demographic groups with a combination of risk factors, including male gender, older age, and urban residence.