Recurrence after preoperative chemotherapy and surgery for gastric adenocarcinoma: a multicenter study

BACKGROUND: In most western European countries perioperative chemotherapy is a part of standard curative treatment for gastric cancer. Nevertheless, recurrence rates remain high after multimodality treatment. This study examines patterns of recurrence in patients receiving perioperative chemotherapy with surgery for gastric cancer in a real-world setting. METHODS: All patients diagnosed with gastric adenocarcinoma between 2010 and 2015 who underwent at least preoperative chemotherapy and a gastrectomy with curative intent (cT1N+/cT2-4a,X; any cN; cM0) in 18 Dutch hospitals were selected from the Netherlands Cancer Registry. Additional data on chemotherapy and recurrence were collected from medical records. Rates, patterns, and timing of recurrence were examined. Multivariable Cox proportional hazard analyses were used to determine prognostic factors for recurrence. RESULTS: 408 patients were identified. After a median follow-up of 27.8 months, 36.8% of the gastric cancer patients had a recurrence of which the majority (88.8%) had distant metastasis. The 1-year recurrence-free survival was 71.8%. The risk of recurrence was higher in patients with an ypN+ stage (HR 4.92, 95% CI 3.35–7.24), partial or no tumor regression (HR 2.63, 95% CI 1.22–5.64), 3 instead of ≥ 6 chemotherapy cycles (HR 3.04, 95% CI 1.99–4.63), R1 resection (HR 1.52, 95% CI 1.02–2.26), and < 15 resected lymph nodes (HR 1.64, 95% CI 1.14–2.37). CONCLUSION: A considerable amount of gastric cancer patients who were treated with curative intent developed a recurrence despite surgery and perioperative treatment. The majority developed distant metastases, therefore, multimodality treatment approaches should be focused on the prevention of distant rather than locoregional recurrences to improve survival.