Efficacy of perioperative FOLFIRINOX chemotherapy versus FLOT chemotherapy in patients with resectable adenocarcinoma of the stomach or gastroesophageal junction (SIEWERT types II–III, cT4aN0M0, T1–4cN+ cM0): preliminary results of the study

Introduction: The main current approach to the treatment of patients with resectable cancer of the stomach and gastroesophageal junction (GEJ) is perioperative FLOT chemotherapy. The mFOLFIRINOX regimen has been shown to be effective and safe in disseminated adenocarcinoma of the stomach and GEJ. This article presents preliminary results of the efficacy and safety assessment of perioperative FOLFIRINOX chemotherapy in patients with resectable cancer of the stomach and gastroesophageal junction. Materials and Methods: The FOLFIRINOX / FLOT study is a phase 2 / 3 open-label, randomized trial. Study enrollment was started in January 2019 and is currently ongoing. The inclusion criteria are: histologically confirmed resectable adenocarcinoma of the stomach or gastroesophageal junction, Siewert types II–III, clinical stage cT4aN0M0, cT1–4N1–3M0 or cT2–4N0–3M0, with total or subtotal involvement of the stomach. The following regimens were used for perioperative chemotherapy: FLOT — docetaxel 50 mg / m2 on day 1, oxaliplatin 85 mg / m2 on day 1, leucovorin 200 mg / 2 on day 1, 5FU 2600 mg / m2  × 24 hours starting on day 1, or mFOLFIRINOX — irinotecan 180 mg / m2 on day 1, oxaliplatin 85 mg / 2 on day 1, leucovorin 200 mg / m2 on day 1, 5FU 250 mg / m2 bolus on day 1 and then 2200 mg / m2  × 48 hours on day 1. The primary endpoint was 5‑year overall survival. Results: All planned preoperative courses of chemotherapy had been administered to 25 (86 %) patients in the FLOT group (n = 29) and 22 (92 %) patients in the FOLFIRINOX group (n = 24). Four (12 %) and 2 (8 %) patients in the FLOT and FOLFIRINOX groups, respectively, discontinued the treatment. The surgical staging was used in 48 patients (91 %) (25 [86 %] in the FLOT group and 23 [96 %] in the FOLFIRINOX group). Complete tumor regression (Mandard grade 1) had been achieved in 4 patients (2 [7 %] in the FLOT group and 2 [8 %] in the FOLFIRINOX group). Postoperative complications were detected in 2 patients (8 %) in the FLOT group and 4 (17 %) in the FOLFRIRNOX group. Thirty-three patients (62 %) received all scheduled postoperative treatment courses (n = 19, 66 % for FLOT and n = 14, 58 % for FOLFIRINOX). Conclusions: The preliminary results of the FOLFIRINOX / FLOT study showed comparable tolerability of the regimens and comparable complete pathological response rates. However, there was a higher incidence of postoperative complications detected among patients who received the FOLFIRINOX regimen compared to the FLOT group.