P-OGC45 Could lymphatic, vascular or perineural invasion status improve clinical staging prior to oesophagectomy?

Abstract

Abstract Background Unimodal treatment of oesophagogastric cancer (OGC) with surgery only is currently reserved for patients with early disease. Presence of vascular (VI), perineural (PNI) or lymphatic vessel invasion (LI) in pathological samples have been shown to be negative prognostic indicators of survival. These factors have been found to be associated with more advanced disease. Staging of OGC has limitations and in neoadjuvant naive populations it has been shown to be imperfect. It is unknown whether VI, PNI or LI could play any role during the staging process. Methods Patients with early disease (cT2 or less and cN0) who underwent unimodal treatment of their oesophageal or junctional cancer with oesophagectomy between 2010 and 2019 in a single centre were included in this study. Therelationship between presence of LI, VI and PNI on pathological samples with incorrect staging/upstaging indicating locally advanced disease (defined as pT3+ or pN+) was studied using logistic regression model. Results There were 128 patients included. 26 patients (20%) were upstaged to pT3+ or pN+. LI, VI and PNI were present in 18%, 11% and 8% respectively. The presence of LI and clinical T stage were independently predictive of incorrect staging/upstaging in multivariable logistic regression analysis. LI (OR 12.5 95%CI 3.7-42.8, p < 0.001) and cT2 (OR 5.9 95%CI 1.5-23.2, p = 0.01). Conclusions These results indicate that the presence of LI from pathological samples is a strong independent prognostic factor of incorrect staging which would normally favour neoadjuvant treatment. The presence of LI suggests aggressive disease. Further studies should concentrate on the possibility of obtaining LI status from preoperative biopsies or endoscopic mucosal resection samples. This staging information could play an important role in deciding whether neoadjuvant therapy is indicated in patients staged as early disease.