Family History of Cancer and Risk of Biliary Tract Cancers: Results from the Biliary Tract Cancers Pooling Project

SEOM clinical guidelines for pancreatic and biliary tract cancer (2020)

Pancreatic cancer (PC) and biliary tract cancer (BTC) are both aggressive and highly fatal malignancies. Nowadays we have a profound knowledge about the molecular landscape of these neoplasms and this has allowed new therapeutic options. Surgery is the only potentially curative therapy in both cancers, but disease recurrence is frequent. In PC, adjuvant treatment with mFOLFIRINOX has improved overall survival (OS) and in BTC adjuvant treatment with capecitabine seems to improve OS and relapse-free survival. Concomitant radio-chemotherapy could also be considered following R1 surgery in both neoplasms. Neoadjuvant treatment represents the best option for achieving an R0 resection in borderline PC. Upfront systemic chemotherapy is the treatment of choice in unresectable locally advanced PC and BTC; then locoregional therapy could be considered after an initial period of at least 3-4 months of systemic chemotherapy. In metastatic PC, FOLFIRINOX or Gemcitabine plus nab-paclitaxel have improved OS compared with gemcitabine alone. In metastatic BTC, cisplatin plus gemcitabine constitute the standard treatment. Progress in the knowledge of molecular biology has enabled the identification of new targets for therapy with encouraging results that could in the future improve the survival and quality of life of patients with PC and BTC.

Anthropometric Risk Factors for Cancers of the Biliary Tract in the Biliary Tract Cancers Pooling Project

Biliary tract cancers are rare but highly fatal with poorly understood etiology. Identifying potentially modifiable risk factors for these cancers is essential for prevention. Here we estimated the relationship between adiposity and cancer across the biliary tract, including cancers of the gallbladder (GBC), intrahepatic bile ducts (IHBDC), extrahepatic bile ducts (EHBDC), and the ampulla of Vater (AVC). We pooled data from 27 prospective cohorts with over 2.7 million adults. Adiposity was measured using baseline body mass index (BMI), waist circumference, hip circumference, waist-to-hip, and waist-to-height ratios. HRs and 95% confidence intervals (95% CI) were estimated using Cox proportional hazards models adjusted for sex, education, race, smoking, and alcohol consumption with age as the time metric and the baseline hazard stratified by study. During 37,883,648 person-years of follow-up, 1,343 GBC cases, 1,194 EHBDC cases, 784 IHBDC cases, and 623 AVC cases occurred. For each 5 kg/m2 increase in BMI, there were risk increases for GBC (HR = 1.27; 95% CI, 1.19-1.36), IHBDC (HR = 1.32; 95% CI, 1.21-1.45), and EHBDC (HR = 1.13; 95% CI, 1.03-1.23), but not AVC (HR = 0.99; 95% CI, 0.88-1.11). Increasing waist circumference, hip circumference, waist-to-hip ratio, and waist-to-height ratio were associated with GBC and IHBDC but not EHBDC or AVC. These results indicate that adult adiposity is associated with an increased risk of biliary tract cancer, particularly GBC and IHBDC. Moreover, they provide evidence for recommending weight maintenance programs to reduce the risk of developing these cancers. SIGNIFICANCE: These findings identify a correlation between adiposity and biliary tract cancers, indicating that weight management programs may help minimize the risk of these diseases.

Epidemiology of gallbladder cancer

According to GLOBOCAN 2018 data, gallbladder cancer (GBC) accounts for 1.2% of all global cancer diagnoses, but 1.7% of all cancer deaths. Only 1 in 5 GBC cases in the United States is diagnosed at an early stage, and median survival for advanced stage cancer is no more than about a year. The incidence of the disease is increasing in the developed world. Gallstones, biliary cysts, carcinogen exposure, typhoid, and Helicobacter pylori infection, and abnormal pancreaticobiliary duct junctions are all risk factors, many of which account for its geographical, ethnic and sex distribution. Genetics also plays a strong role, as about a quarter of GBC cases are considered familial, and certain ethnicities, such as Native Americans, are at far higher risk for the neoplasm. Prevention includes weight loss, vaccination against and treatment of bacterial infections, early detection and elimination of polyps and cysts, and avoidance of oral estrogen replacement therapy.

Biliary tract cancer incidence and trends in the United States by demographic group, 1999-2013

BACKGROUND

Biliary tract cancers (BTCs) are rare but deadly cancers (gallbladder cancer [GBC], intrahepatic cholangiocarcinoma [ICC], extrahepatic cholangiocarcinoma [ECC], and ampulla of Vater cancer [AVC]). A recent US study reported increasing GBC incidence among people younger than 45 years and blacks; however, it did not examine trends for other biliary tract sites.

METHODS

This study characterized demographic differences in BTC incidence rates and time trends by anatomic site. Population-based North American Association of Central Cancer Registries data were used to calculate age-adjusted incidence rates, incidence rate ratios (IRRs), and estimated annual percent changes (eAPCs) for 1999-2013 by site and demographic group. For sites with significant differences in eAPC by age group, IRRs were compared by age group.

RESULTS

GBC incidence rates declined among women (eAPC, -0.5%/y; P = .01) and all racial/ethnic groups except for non-Hispanic blacks, among whom rates increased (1.8%/y; P < .0001). Although GBC rates increased among 18- to 44-year-olds (eAPC, 1.8%/y; P = .01), they decreased among people 45 years old or older (-0.4%/y; P = .009). Sex (P < .0001) and racial/ethnic differences (P = .003 to .02) in GBC incidence were larger for younger people than older people. During this period, ICC (eAPC, 3.2%/y; P < .0001) and ECC rates (1.8%/y; P = .001) steadily increased across sex and racial/ethnic groups. Although AVC incidence rates increased among younger adults (eAPC, 1.8%/y; P = .03) but not older adults (-0.20%/y; P = .30), sex and racial/ethnic IRRs did not differ by age.

CONCLUSIONS

Differential patterns of BTC rates and temporal trends have been identified by anatomic site and demographic groups. These findings highlight the need for large pooling projects to evaluate BTC risk factors by anatomic site.