Prognosis of distal pancreatic cancers controlled by stage
Guopei Luo, Kaizhou Jin, Cheng He, Meng Guo, Yitao Gong, Zhiyao Fan, Chao Yang, Qiuyi Huang, Quanxing Ni, Chen Liu, Xianjun Yu
Abstract
Patients with distal (body/tail) pancreatic cancer have been found to present worse outcome than patients with head cancer, which is generally attributed to the great proportion of advanced stages for body/tail cancers upon detection. However, differences in prognosis between head and body/tail pancreatic cancers controlled by stage have not been analyzed in-depth. In this study, differences in prognosis between head and body/tail pancreatic cancers were examined using the Surveillance, Epidemiology, and End Results Program (SEER) (1973-2014 registry, 85,715 cases). We found that patients with body/tail pancreatic cancer had worse prognosis than patients with head cancer for all combined stages [adjusted hazard ratio (HR), 1.03, 95% confidence interval (CI), 1.00-1.05, P=0.025]. Compared with patients with head cancer, patients with body/tail cancer had lower mortality for stage I cancers (HR, 0.85, 95% CI, 0.76-0.94, P=0.001), no difference in mortality for stages II or III (stage II, HR, 1.00, 95% CI, 0.95-1.06, P=0.965; stage III, 0.97, 95% CI, 0.91-1.04, P=0.398), and higher mortality for stage IV (HR, 1.07, 95% CI, 1.04-1.10, P<0.001). In addition, the proportion of body/tail pancreatic cancer increased from 24.9% in 1973 to 36.3% in 2014. Therefore, tumor location of body/tail is an independent adverse prognostic factor for patients with pancreatic cancer. However, this observation is not applicable when controlled by stage (body/tail versus head pancreatic cancer, better stage I, similar stage II/III, and worse stage IV).