Adjuvant chemotherapy indications for stage I gastric cancer patients with negative lymph node

Purpose: Whether adjuvant chemotherapy (AC) has a survival benefit for pathological stage Ⅰ (T1N0 and T2N0) gastric cancer (GC) patients with negative lymph node (N0) remains controversial.

Methods: Patients with surgically resected, histologically confirmed pT1N0 and pT2N0 GC between January 2011 and December 2017 at the National Cancer Center, China, were retrospectively reviewed.

Results: A total of 1601 patients who met the inclusion criteria were identified. Independent risk factors for reduced overall survival (OS) identified in the Cox regression analysis were male sex (hazard ratio [HR] 1.454, 95% confidence interval [CI] 1.127-1.876), age ≥ 65 years (HR 1.367; 95% CI 1.071-1.744 ), T2 stage (HR 1.283; 95% CI 1.005-1.638), tumor size > 3 cm (HR 1.704; 95% CI 1.346-2.158), examined lymph nodes (EN) ≤ 15 (HR 1.327; 95% CI 1.058-1.664), and non-signet ring cell carcinoma (Non-SRCC) (HR 1.639; 95% CI 1.123-2.392). While only T2 stage (HR 1.410; 95% CI 1.026-1.936), tumor size > 3 cm (HR 1.755; 95% CI 1.285-2.397), examined lymph nodes (EN) ≤ 15 (HR 1.489; 95% CI 1.101-2.015) were independent risk factors for cause-specific survival (CSS). We divided patients with pT2N0 into four sub-categories according to two significant prognostic factors (size and EN) and found that only patient in group 3 (EN ≤ 15, size >3 cm) with improved CSS benefit from AC (p = 0.049). More significant CSS benefit from AC was identified in Non-SRCC patients within group 3 (p = 0.034).

Conclusion: An additional survival benefit related to AC is expected for selected pT2N0 patients. Non-SRCC patients with EN ≤ 15 and tumor size >3 cm may be particularly appropriate candidates for AC.