Pathological response and outcome after neoadjuvant chemotherapy with DOC (docetaxel, oxaliplatin, capecitabine) or EOF (epirubicin, oxaliplatin, 5-fluorouracil) for clinical T3-T4 non-metastatic gastric cancer.

Purpose: In this prospective observational study, we sought to compare the efficacy and safety of docetaxel + oxaliplatin + capecitabine (DOC) with epirubicin + oxaliplatin + 5-fluouracil (EOF) as neoadjuvant chemotherapy (NAC) for clinical T3 or T4 non-metastatic gastric cancer (GC) patients.

Methods: The DOC NAC consisted of docetaxel 35 mg/m (days 1-8), oxaliplatin 85 mg/m (day 1), and capecitabine 750 mg/m twice daily (days 1-14), every 3 weeks. The EOF NAC consisted of intravenous (IV) epirubicin 50 mg/m2 combined with IV oxaliplatin 130 mg/m2 on day 1 and continuous infusion 5-fluouracil 750 mg/m2 on days 1-5, every 3 weeks. After 4 cycles of NAC or upon progression during chemotherapy, patients underwent gastrectomy with standard D2 or D3 lymphadenectomy. Pathological complete response rate per Becker tumor regression grading system was the primary endpoint and the secondary endpoints included progression-free survival (2-yr PFS) and 2-year overall survival (2-yr OS) and tolerability.

Results: Overall, we identified 63 patients with T3-4 non-metastatic GC starting either NAC regimen between January 2010 and December 2017 at our Institution: 34 in the DOC group and 29 in EOF group. Thirty patients (88%) in the DOC group and 22 (76%) in the EOF group completed the 4 planned cycles of NAC. Fifty-seven patients received surgery. Results indicated no statistical significant differences between the two groups, and only a trend for some better data in favour of the DOC group. The R0 resection rate was 90.6% and 88.0% for the DOC and EOF cohorts, respectively. The pathological complete response rate was 6.2% in the DOC group and 4.0% in the EOF group. Becker 1-2 pathological response was found in 46.8% of the DOC cohort and 28.0% of the EOF cohort (p = .14). The 2-yr PFS rate was 54.1% for DOC vs. 41.4% for EOF (p = .14) and the 2-yr OS rate was 80.8% for DOC vs. 58.6% for EOF (p = .05). Neutropenia was the most common grade ≥3 toxicity and occurred in 8 (23.5%) patients of the DOC group and 10 (34.4%) patients of the EOF group (p = .33).

Conclusions: These findings seem to confirm the feasibility of NAC for clinically T3 and T4 non-metastatic GC and, despite no statistical significant difference was documented, suggest a trend for better activity and tolerability for the docetaxel-based regimen (DOC) compared to the epirubicin-based combination (EOF).