Abstract 428P
Background
Less than half of the patients with locally advanced gastric and gastroesophageal junction cancer (GC/GEJC) can tolerate all adjuvant cycles of perioperative FLOT chemotherapy. We previously reported the first results of our pilot study investigating avoidance of adjuvant chemotherapy in patients with locally advanced GC/GEJC, who received 8 cycles of total neoadjuvant chemotherapy with FOLFIRINOX regimen followed by surgery. Here, we present updated results.
Methods
Briefly, this was a non-randomized, phase II study that enrolled 119 patients with locally advanced GC/GEJC who received either 8 cycles of total neoadjuvant chemotherapy with FOLFIRINOX regimen (prospective cohort, n = 60) or standard perioperative FLOT chemotherapy (historical control, n = 59), followed by surgery. The primary endpoint was disease-free survival (DFS). Secondary endpoints were the rate of pathological complete response (pCR) by 3 different tumor regression grading (TRG) systems and safety.
Results
The present analysis was performed at a median follow-up of 19.1 months and 24.0 months in the FOLFIRINOX and FLOT groups, respectively. Updated two-year DFS was 70.1% in FOLFIRINOX group and 65.8% in FLOT group (hazard ratio 0.73, 95% CI 0.36-1.49, p=0.384). Among the patients with diffuse type by Lauren classification a significantly higher rate of pCR was achieved following FOLFIRINOX regimen, but not in intestinal type. This was consistent across all TRG systems: pCR rate - 66.7% vs 35.0%, 69.2% vs 47.1% and 71.4% vs 39.1% by Becker, Mandard and Lavnikova systems in patients with diffuse type from FOLFIRINOX and FLOT groups, respectively. Exploratory DFS analysis did not reveal any subgroup of patients that benefited more from any administered regimen. Achieving pCR did not have an impact on DFS. FOLFIRINOX was associated with a lower incidence of peripheral neuropathy (32.2% vs. 50.6% [p=0.009]) and hepatotoxicity (27.1% vs. 50.9% [p=0.004]) compared to FLOT.
Conclusions
Total neoadjuvant chemotherapy with FOLFIRINOX regimen in patients with locally advanced GC/GEJC led to a higher rate of pCR in patients with Lauren diffuse type and wasn’t inferior in terms of DFS compared to perioperative FLOT chemotherapy.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.