J Gastric Cancer.  2016 Jun;16(2):105-110. 10.5230/jgc.2016.16.2.105.

The Influence of Metastatic Lymph Node Ratio on the Treatment Outcomes in the Adjuvant Chemoradiotherapy in Stomach Tumors (ARTIST) Trial: A Phase III Trial

• Kim Y
• Park SH
• Kim KM
• Choi MG
• Lee JH
• Sohn TS
• Bae JM
• Kim S
• Lee SJ
• Kim ST
• Lee J
• Park JO
• Park YS
• Lim HY
• Kang WK

• KMID: 2328077
• DOI: http://doi.org/10.5230/jgc.2016.16.2.105

Abstract

PURPOSE
In the Adjuvant Chemoradiotherapy in Stomach Tumors (ARTIST) trial, we investigated whether chemoradiotherapy after D2 gastrectomy reduces the rate of recurrence. Recently, the ratio of metastatic lymph nodes to examined lymph nodes (N ratio) has been proposed as an independent prognostic factor in gastric cancer (GC). The aim of this study was to investigate the relationship between the metastatic N ratio and prognosis of GC after curative D2 surgery.
MATERIALS AND METHODS
We retrospectively reviewed the data of 458 ARTIST patients who underwent D2 gastrectomy followed by adjuvant chemotherapy (XP, n=228) or chemoradiotherapy (XPRT, n=230). The disease-free survival (DFS) rates of patients were used to evaluate the influence of N ratio on the treatment outcome. To achieve this, 4 different N ratio categories (0%, 1%~9%, 10%~25%, and >25%) were compared on the basis of their influence on the treatment outcome.
RESULTS
On multivariate analysis, the N ratio remained an independent prognostic factor for DFS. The hazard ratios (HRs) for the N ratio categories of 0%, 1%~9%, 10%~25%, and >25% were 1, 1.061, 1.202, and 3.571, respectively. In patients having N ratio >25%, the 5-year DFS rates were 55% and 28% for the XPRT and XP arms, respectively (HR, 0.527; 95% confidence interval, 0.307~0.904; P=0.020).
CONCLUSIONS
In patients with curatively resected GC, the N ratio was independently associated with DFS. Although this finding warrants further investigation in future prospective studies, the benefit of chemoradiotherapy for D2 resected GC appears to be more beneficial in cancers having N ratios >25%.

Keyword

Stomach neoplasms; Lymph node; Prognosis

MeSH Terms

Arm
Chemoradiotherapy
Chemoradiotherapy, Adjuvant*
Chemotherapy, Adjuvant
Disease-Free Survival
Gastrectomy
Humans
Lymph Nodes*
Multivariate Analysis
Prognosis
Prospective Studies
Recurrence
Retrospective Studies
Stomach Neoplasms
Stomach*
Treatment Outcome

Figure

• 

  Fig. 1 (A) Disease-free survival curves according to N ratio. (B) Overall survival curves according to N ratio. The cut-off values for the N ratios are as follows: solid (black) line, 0%; dashed line, 1~9%; dotted line, 10~25%; and solid (gray) line, >25%. N ratio = the ratio of metastatic lymph nodes to examined lymph nodes.

• 

  Fig. 2 (A) Disease-free survival curves for patients with N ratios of 0%~25%. (B) Overall survival curves for patients with N ratios of 0%~25%. Solid line, XPRT arm; dotted line, XP arm. XP = capecitabine plus cisplatin; XPRT = concurrent chemoradiotherapy with XP; N ratio = the ratio of metastatic lymph nodes to examined lymph nodes.

• 

  Fig. 3 (A) Disease-free survival curves for patients with N ratios >25% (B) Overall survival curves for patients with N ratios >25%. Solid line, XPRT arm; dotted line, XP arm. XP = capecitabine plus cisplatin; XPRT = concurrent chemoradiotherapy with XP; N ratio = the ratio of metastatic lymph nodes to examined lymph nodes.

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