Lymphovascular invasion as a predictor for lymph node metastasis and a prognostic factor in gastric cancer patients under 70 years of age: A retrospective analysis

BACKGROUND

Accumulating evidence has confirmed the potential prognostic value of LVI in patients with cancers. This aim of the current study was to clarify the potential relationship between LVI and lymph node metastasis, establish predictive clinicopathologic prognostic factors for LVI and lymph node metastasis, and determine the prognostic significance of LVI for patients younger than 70 years with resected gastric cancer.

METHODS

Overall survival rates were calculated using Kaplan-Meier analysis. Differences in proportions of patients were tested with the χ² test. Univariate and multivariate analyses were applied to identify independent prognostic factors. Logistic regression analysis was employed to identify the risk factors predicting the presence of LVI and LN metastasis.

RESULTS

Univariate analysis led to the identification of tumor size, LVI and pN stage as factors significantly correlated with prognosis. Multivariate analysis demonstrated that tumor size, LVI, pN stage, and number of LNs retrieved are independent prognostic factors for the entire population. Logistic regression analysis proved that LVI and pT stage were significantly associated with LN metastasis.

CONCLUSION

LVI is an independent prognostic factor predicting LN metastasis and a strongly independent predictor of survival for patients with resected gastric cancer. We recommend that LVI should be taken into account as an important adjuvant prognostic factor, specially for pN0 cases with inadequate LNs retrieved. And the maximum number of LNs possible should be retrieved for optimal staging, especially for patients with higher cT stage.

What make differences in the outcome of adjuvant treatments for resected gastric cancer?

After a long history of Dark Age of adjuvant chemotherapy for gastric cancer, definite evidences of survival benefit from adjuvant treatment have been reported since 2000s. These survival benefits are likely attributed to something new approach different from pervious studies. In 2001, South West Oncology Group INT0116 trial yielded survival benefit in curatively resected gastric cancer patients with postoperative chemoradiotherapy [5-fluorouracil (5-FU) + Leucovorin + radiotherapy], followed by positive result by MAGIC Trial, employing peri-operative(pre- and postoperative chemotherapy with Epirubicin, cisplatin (CDDP), 5-fluorouracil (ECF) regimen in patients with curative resection. A novel drug [S1: ACTS-GC (Adjuvant chemotherapy trial of TS-1 for gastric cancer) in 2007], or new drug combination chemotherapys [CDDP + 5-FU: FNCLCC/FFCD (Federation Nationale des Centres de Lutte contre le cancer/Federation Francophone de Cancerologie Digestive) in 2011, Capecitabine + Oxaliplatin: CLASSIC in 2012] also produced positive results in terms of improved prognosis. Neoadjuvant or perioperative chemotherapy, novel anti-cancer drugs, and chemoradiotherapy might be the key words to develop further improvement in the adjuvant treatment of resectable gastric cancer. Moreover, it is not new but still true to stress the importance of D2 surgery as the baseline treatment in order to minimize the amount of residual tumor after surgery.