Prognostic Significance of Lymphatic, Venous and Perineural Invasion After Neoadjuvant Chemotherapy in Patients with Gastric Adenocarcinoma

Abstract

Background. The significance of perineural (PNI), lymphatic (LI) and venous invasion (VI) in gastric cancer patients who have received neoadjuvant chemotherapy is unclear. The aim of this study is to determine the incidence and prognostic significance of LI, VI and PNI in these patients. Patients and Methods. Consecutive patients treated with neoadjuvant chemotherapy followed by gastrectomy with D2 lymphadenectomy were reviewed. Presence of LI, VI and PNI was recorded and correlated with clinical outcomes. Results. A total of 243 patients underwent gastrectomy after neoadjuvant therapy for gastric adenocarcinoma. LI was identified in 129 (53%), VI in 107 (44%) and PNI in 116 (48%) of patients.

Concurrent lymphovascular and perineural invasion after preoperative therapy for gastric adenocarcinoma is associated with decreased survival

“…A few authors have evaluated the prognostic significance of LVI and/or PNI after preoperative chemotherapy. Most recently, Woodham and colleagues found that LVI, venous invasion (VI), and PNI were each associated with more advanced ypT and ypN categories, as well as a higher number of positive LNs, after preoperative chemotherapy 11 . These findings are consistent with our findings.…”

“…Many authors have demonstrated a significant association between the presence of LVI and the presence of PNI, findings that were replicated in our study 6,8‐11 . This is important, as our findings demonstrate a significant prognostic impact of concurrent LVI and PNI on OS and DFS, while either factor alone was not independently predictive of survival outcomes.…”

“…The patients in that study, however, were treated with adjuvant chemotherapy rather than preoperative therapy. In patients treated with preoperative chemotherapy, Woodham et al also found greater impact on survival outcomes with an increasing number of invasion‐related factors present, though the combinations of factors were not specified 11 . While they also demonstrated worse OS and DFS in patients with LVI, VI or PNI, PNI was the only invasion‐related factor independently predictive of worse survival 11 .…”

“…In patients treated with preoperative chemotherapy, Woodham et al also found greater impact on survival outcomes with an increasing number of invasion‐related factors present, though the combinations of factors were not specified 11 . While they also demonstrated worse OS and DFS in patients with LVI, VI or PNI, PNI was the only invasion‐related factor independently predictive of worse survival 11 . In our study, OS and DFS were markedly shorter in patients with PNI alone than in those with neither factor, and while this did not reach statistical significance on univariate or multivariable analyses, it raises the question whether the presence of PNI is driving the decreased survival in the patients with both LVI and PNI present.…”

ASO Author Reflections: Gastric Cancer Staging: More than Just TNM?

“…This study reveals additional prognostic factors for patients with gastric adenocarcinoma who were treated with neo-adjuvant chemotherapy and surgery. 5 The presence of lymphatic, venous and perineural invasion are features of aggressive tumours. These histological findings in the resection sample may play a prognostic role.…”