Obstructive Sleep Apnea and Pathological Characteristics of Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND Prospective studies have identified obstructive sleep apnea (OSA) as a risk factor for increased overall cancer incidence and mortality. The potential role of OSA in the risk or progression of specific cancers is not well known. We hypothesized that pathological differences in pancreatic cancers from OSA cases compared to non-OSA cases would implicate OSA in pancreatic cancer progression. METHODS We reviewed the medical records of 1031 patients who underwent surgical resection without neoadjuvant therapy for pancreatic ductal adenocarcinoma (PDAC) at Johns Hopkins Hospital between 2003 and 2014 and compared the TNM classification of their cancer and their overall survival by patient OSA status. RESULTS OSA cases were significantly more likely than non-OSA cases to have lymph node-negative tumors (37.7% vs. 21.8%, p = 0.004). Differences in the prevalence of nodal involvement of OSA vs. non-OSA cases were not associated with differences in other pathological characteristics such as tumor size, tumor location, resection margin status, vascular or perineural invasion, or other comorbidities more common to OSA cases (BMI, smoking, diabetes). A logistic regression model found that a diagnosis of OSA was an independent predictor of lymph node status (hazard ratio, 0.051, p = 0.038). Patients with OSA had similar overall survival compared to those without OSA (HR, 0.89, (0.65-1.24), p = 0.41). CONCLUSION The observed pathological differences between OSA-associated and non-OSA-associated pancreatic cancers supports the hypothesis that OSA can influence the pathologic features of pancreatic ductal adenocarcinoma.