Familial pancreatic cancer risk: a population-based study in Utah.

INTRODUCTION

Pancreas adenocarcinoma (PC) has an undefined hereditary component. We quantified the familial risk of PC among relatives of patients diagnosed with PC and stratified it based on anatomic location of PC and age and sex of the proband.

METHODS

This is a retrospective, population-based, case-control study of PC diagnosed in Utah between 1980 and 2011. The Utah population database and cancer registry were used to identify index patients with PC. The risk of PC in first-degree relatives (FDRs), second-degree relatives (SDRs), and first cousins (FCs) of probands was compared with randomly selected sex- and age-matched population controls.

RESULTS

A total of 4,095 patients and 40,933 controls were identified. The relative risk (RR) of PC was 1.76 (95% CI 1.35-2.29) in FDRs, 1.42 (95% CI 1.18-1.7) in SDRs and 1.08 (95% CI 0.95-1.23) in FCs of probands compared to relatives of PC-free controls. The RR were elevated in FDRs (1.96, 95% CI 1.45-2.65), SDRs (1.54, 95% CI 1.19-1.98) and FCs (1.18, 95% CI 1.0-1.64) of female probands. Among probands diagnosed as < 65 years, RR was 2.12 (95% CI 1.37-3.28) in FDRs, 1.94 (95% CI 1.44-2.62) in SDRs, and 1.28 (95% CI 1.0-1.64) in FCs. Overall, the RR for PC was elevated in FDRs regardless of the anatomic location of PC.

DISCUSSION

There is an increased risk of PC in FDR and more distant relatives of patients with PC. Relatives of female patients with PC and patients diagnosed at age < 65 years are at a significantly increased risk of PC.