Neo-adjuvant chemotherapy followed by surgery and chemotherapy or by surgery and chemoradiotherapy for patients with resectable gastric cancer (CRITICS)

Preoperative chemotherapy does not influence the number of evaluable lymph nodes in resected gastric cancer

BACKGROUND

While it is suggested that more than 15 lymph nodes (LNs) should be evaluated for accurate staging of gastric cancer, LN yield in western countries is generally low. The effect of preoperative chemotherapy on LN yield in gastric cancer is unknown. The aim of the present study is to determine whether preoperative chemotherapy is associated with any difference in the number of LNs obtained from specimens of patients who underwent curative surgery for gastric adenocarcinoma.

PATIENTS AND METHODS

In 1205 patients from Memorial Sloan-Kettering Cancer Center (MSKCC) and 1220 patients from the Netherlands Cancer Registry (NCR) who underwent a gastrectomy with curative intent for gastric adenocarcinoma without receiving preoperative radiotherapy, LN yield was analyzed, comparing patients who received preoperative chemotherapy and patients who received no preoperative therapy.

RESULTS

Of the 2425 patients who underwent a gastrectomy, 14% received preoperative chemotherapy. Median LN yields were 23 at MSKCC and 10 in the NCR. Despite this twofold difference in LN yield between the two populations, with multivariate Poisson regression, chemotherapy was not associated with LN yield of either population. Variables associated with increased LN yield were institution, female sex, lower age, total (versus distal) gastrectomy and increasing T-stage.

CONCLUSIONS

In this patient series, treatment at MSKCC, female sex, lower age, total gastrectomy and increasing primary tumor stage were associated with a higher number of evaluated LNs. Preoperative chemotherapy was not associated with a decrease in LN yield. Evaluating more than 15 LNs after gastrectomy is feasible, with or without preoperative chemotherapy.

Chemotherapy for operable gastric cancer: current perspectives

The majority of gastric cancer patients present with advanced, incurable disease and only a minority have localised disease that is suitable for radical treatment. A benefit has generally been demonstrated from adding chemotherapy to surgery for early disease though there are marked differences in how this is done globally. Whilst a perioperative approach, with chemotherapy given before and after gastric surgery is commonly used in the Europe and Australia most patients with operable gastric cancer in North America are treated with surgery and postoperative chemoradiation. In contrast, in East Asia, adjuvant fluoropyrimidine chemotherapy alone is used following D2 gastric resection surgery. However, despite the multimodality treatments, outcomes remain suboptimal as the majority of those treated for localised disease eventually relapse with incurable loco-regional or distant metastases. At the current time, an unmet need exists to further understand the biology of this aggressive disease and develop more efficacious therapies that can improve outcomes from this aggressive disease.