M. Lin1, M. Gao1, R. A. Patel2, M. J. Cavnar1, J. Kim1 1University of Kentucky,Surgery,Lexington, KY, USA 2University of Kentucky,Medical Oncology,Lexington, KY, USA
Introduction: Multiple primary cancers are defined as two or more tumors of different origin arising in the same individual. Since nationwide cancer statistics have shown Kentucky to have the highest cancer incidence rate and we have anecdotally observed increased multiple primary cancers in pancreatic cancer patients in Kentucky, we sought to formally analyze the incidence of multiple primary cancers. Our second objective was to determine whether tobacco use, a major risk factor for pancreatic cancer, has an association with multiple primary cancers.
Methods: We analyzed the Kentucky Cancer Registry, which is the statewide cancer registry, for patients 18-90 years old diagnosed with pancreatic cancer in Kentucky between 2010-2016. We reviewed data on primary cancers diagnosed throughout the patients’ lifetimes and assessed their tobacco use.
Results: Our analyses revealed 4398 patients were diagnosed with pancreatic cancer in Kentucky during the study period, comprising 51% males and 49% females; and by race, 92% whites, 7.5% blacks, and 0.5% other. The majority of patients (n=2428, 55.2%) were 60-79 years old. For most patients (n=3425, 77.8%), pancreatic cancer was the only primary malignancy in the patient’s lifetime. Importantly, 811 (18.4%) patients had at least 1 additional malignancy associated with 43% tobacco use; and 135 (3.06%) patients had at least 2 additional malignancies associated with 48% tobacco use.
Conclusion: Nearly 1 in 5 pancreatic cancer patients in Kentucky have a second primary cancer, which is higher than reported nationwide ranges of multiple cancers (0.734% to 11.4%). As the first report of the highest incidence of multiple primary cancers in pancreatic cancer patients, it is unclear whether this phenomenon is secondary to known risk factors such as tobacco use or genetic susceptibilities. These data warrant further investigation to identify risk factors leading to additional cancer diagnoses in patients with pancreatic cancer in Kentucky.