Pancreatic Cancer Incidence Increasing Among Young Women in the US

Over the past 2 decades, incidence of pancreatic cancer increased among younger women, especially between the ages of 15 and 34 years, compared with young men of the same age, according to study findings published in Gastroenterology.

Researchers conducted a population- based, time trend analysis from 2001 to 2018. They obtained data from the National Program of Cancer Registries (NPCR) while excluding Surveillance Epidemiology and End Results (SEER) data.

During this time period, 454,611 patients (48.9% women) in the United States (US) received a diagnosis of pancreatic cancer. The researchers stratified these patients into 4 groups according to age: 15 to 34 years, 35 to 54 years, 55 years and older, and all patients younger than 55 years of age. They further subdivided the patients according to biological sex.

Overall, across all age groups, women demonstrated a lower incidence of pancreatic cancer compared with men (10.69 per 100,000 (95% CI, 10.64-10.73) vs 13.95 per 100,000 (95% CI, 13.90-14.01).

However, when analyzing the subgroups stratified by age, the researchers observed a trend of significantly increasing pancreatic cancer incidence in young women ages 15 to 34 years compared with young men of the same age (average annual percentage change [AAPC] in incidence in women, 6.45%; 95% CI, 5.36%-7.55%; P <.001 vs AAPC in men, 2.97%; 95% CI, 1.69%-4.27%; P <.001).

They also analyzed pancreatic cancer incidence in the different contexts of patient demographics, tumor characteristics, and mortality rates. The researchers noted rising incidence of pancreatic cancer among Black women (age-adjusted incidence rate, 2.23%; P <.001), particularly increased rates of the adenocarcinoma histopathological subtype (age-adjusted incidence rate, 0.89%; P =.003) and tumors located in the head of the pancreas (age-adjusted incidence rate, 1.64%; P <.001).

Mortality due to pancreatic cancer remained unchanged in women compared with declining mortality among men (AAPC difference, 0.54%; P =.001). These trends may explain the increasing incidence of pancreatic cancer in younger women compared with younger men.

“Using nationwide data, covering [approximately] 64.5% of [the] US population, we externally validate a rapidly increasing aIR [age-adjusted incidence rate] of PC [pancreatic cancer] in younger women,” the study authors wrote. “There was a big separation of the incidence trend between women and men aged 15-34 between 2001-2018 (>200% difference), and it did not show slowing down.”

Study limitations include loss of records, coding errors, lack of information on several variables which precluded analysis of possible risk factors for increased cancer incidence, lack of histopathological data regarding lineage and origin of the cancer, possible detection bias, and potential overlap between SEER and NPCR databases despite the attempt to exclude SEER data.