Spatial Epidemiology of Pancreatic Cancer in South Dakota

Pancreatic cancer is the fourth leading cause of cancer-related mortality in the United States. Descriptive epidemiology of pancreatic cancer in South Dakota has not been studied before.

All cases of pancreatic cancer reported to the SD Cancer Registry between January 2005 and December 2014 were included in the study. Variables collected included demographics, geographical location including county of residence and zip codes, date of diagnosis, date of last contact or follow-up, size and location of the tumor, grade of the tumor, diagnostic modality as well as therapeutic interventions. Log rank test was used to compare survival curves. Kaplan-Meier product limit estimates were provided. Data was analyzed using SAS 9.1.4 software.

One thousand sixty-four cases of pancreatic cancer were reported. Median age was 73 years. Cumulative age-adjusted incidence rate for pancreatic cancer for 2005-2014 was 11.1. Cumulative age-adjusted mortality rate for pancreatic cancer for 2005-2014 was 10.2. Almost half of these patients had distant metastasis at the time of presentation (n = 536; 50.4%). Overall, median survival was 5 months. Median survival for patients under the age of 60 years was 9.5 months as opposed to median survival for patients 60 years or older which was 3.9 months. Median survival of patients with well-differentiated, moderately differentiated, and poorly differentiated tumors, was 20.8 months, 8.2 months and 6.3 months respectively (p value = 0.0017).

Incidence of pancreatic cancer in South Dakota is similar to the national trends in the United States. Age at presentation, location of tumor in pancreas, and biological behavior of tumor were all predictors of survival in patients with pancreatic cancer.