RA09.03: PERINEURAL INVASION (PNI) IN ESOPHAGEAL CANCER: IMPROVING THE VALUE OF MODERN STAGING: A META-ANALYSIS

Abstract

Abstract Background Esophageal cancer treatment is largely determined by tumor stage. Despite improvements made in the treatment of different types of this malignant disease, staging has still in continuous renewal. The role of perineural invasion (PNI) in staging remains debated. We have assessed the relation of PNI with metastatic pattern to evaluate whether PNI might add significant new information to staging. Methods We performed a systematic literature search that was focused on the PNI in esophageal cancer published up to February 2018. Studies with neoadjuvant-treated patients were excluded. Data on T stage, N stage and other characteristics were extracted. Data were analyzed for the relevance of the presence of PNI, lymph node metastases, and the tumor invasion on the depth of esophageal structure and outcomes. Results A total of 9 cohorts were retrieved, covering 2207 patients. PNIs are invariably associated with poor outcome. Moreover, a total analysis of 2207 patients showed improved PNI in T3 + T4 (OR = 0.25, 95% CI: 0.15–0.44, and P < 0.00001), 674 of 2204 patients showed PNI more favored in N positive (OR = 0.61, 95% CI: 0.38–0.96, and P = 0.03), and 461 of 1788 patients showed improved PNI in G3 + G4 (OR = 0.70, 95% CI: 0.54–0.92, and P = 0.010) compared with T1 + T2, N − , and G1 + G2 patients, respectively. Conclusion PNI is an adverse prognostic factor in esophageal cancer. We have shown that PNIs have valuable prognostic information in advanced T, N stage and poor cell differentiation. Therefore, we propose that PNI may provide a vital clue to esophageal cancer staging in the future. Disclosure All authors have declared no conflicts of interest.