Risk of head and neck cancer after chronic pancreatitis

BACKGROUND: To evaluate the relation of head and neck cancer to chronic pancreatitis by analyzing Taiwan’s National Health Insurance Research Database. METHODS: We identified 11,237 patients with chronic pancreatitis as the case cohort, which was propensity score matched with another 11,237 patients without chronic pancreatitis by sex, age, index year, and comorbidities. We followed both cohorts between January 1, 2000, and December 31, 2011 to measure the incidence of head and neck cancer. RESULTS: Compared with patients without chronic pancreatitis, those with chronic pancreatitis were associated a greater risk of head and neck cancer [adjusted HR (aHR) =1.31, 95% confidence interval (CI): 1.07–1.60] and had a higher incidence of head and neck cancer (log-rank test, P<0.001). The experimental event rate of head and neck cancer for the chronic pancreatitis cohort was 1.90% (213/11,237) and control event rate of head and neck cancer for the non-chronic pancreatitis cohort was 1.60% (180/11,237), respectively. Therefore, the chronic pancreatitis cohort had a 0.30% of absolute risk increase and approximately 333 of number needed to harm for the development of head and neck cancer, respectively. Compared with the individuals without chronic pancreatitis and any other comorbidity, the risk of head and neck cancer for the chronic pancreatitis patients without comorbidities was 2.79 folds and the risk increased to 4.32, 3.33, 3.22, 4.44, and 5.78 folds in the presence of any one, any two, any three, any four, and more than five comorbidities, respectively. CONCLUSIONS: Chronic pancreatitis is related to an increased risk of head and neck cancer, and the presence of comorbidity increases the risk more. It requires more studies to find more co-existing risk factors or comorbidities to recommend a screening program for the CP patients. Moreover, it needs more studies to ascertain the pathogenesis for the aforementioned association and the limited knowledge of the patients' smoking habits and alcohol drinking is the major limitation of this observational study.