Preoperative chemotherapy with a modified docetaxel, cisplatin, and S-1 regimen, followed by gastrectomy and lymphadenectomy for gastric cancer with bulky lymph nodes.

[PURPOSE] The appropriate regimen and dosage of preoperative chemotherapy for gastric cancer (GC) with bulky lymph nodes (LNs) remain controversial. We conducted this study to evaluate the efficacy of preoperative chemotherapy using a modified regimen of docetaxel, cisplatin, and S-1 (DCS) for GC with bulky LNs, assessing feasibility, toxicity, response rate, and oncological outcomes.

[METHODS] Thirty-two patients who had GC with bulky LNs diagnosed between Jan, 2018 and Oct, 2022 received three or four cycles of modified DCS regimen preoperatively. The primary outcome was 3 year overall survival (OS).

[RESULTS] The completion rate of preoperative chemotherapy was 90.6% (4 cycles: 50.0%, 3 cycles: 40.6%). The disease control rate (DCR) and clinical response rate (RR) were 87.5% and 81.3%, respectively. Grade-3/4 neutropenia and anemia developed in 6.2% and 9.4%, respectively. Twenty-two patients with partial response (PR) agreed to undergo gastrectomy and LN dissection. Pathologic complete response (CR) was achieved in 15.6%. After surgery, there were no grade >  = 3 postoperative complications. The R0-resection rate was 65.6%. The 3 year OS and progression-free survival (PFS) rates were 43.0% and 37%, respectively, for all eligible patients. The 3 year OS and PFS of patients in the surgery group with negative para-aortic LNs were 58% and 47.0%, respectively.

[CONCLUSION] Preoperative chemotherapy with a modified DCS regimen demonstrated high tolerance, a clinical response rate, and satisfactory 3 year survival outcomes. Thus, a preoperative modified DCS regimen with 3-4 cycles is a promising approach for GC with bulky LNs.