The impact of neoadjuvant therapy in patients with left-sided resectable pancreatic cancer: an international multicenter study

Mené sur 2 282 patients ayant subi une résection gauche pour un cancer du pancréas, cet essai international (76 centres, 18 pays, 4 continents) évalue l'effet d'un traitement néoadjuvant sur la survie globale

Annals of Oncology, sous presse, 2025, article en libre accès

Résumé en anglais

Purpose : To assess the association between neoadjuvant therapy and overall survival (OS) in patients with left-sided resectable pancreatic cancer (RPC) compared to upfront surgery.

Background : Left-sided pancreatic cancer is associated with worse OS compared to right-sided pancreatic cancer. Although neoadjuvant therapy is currently seen as not effective in patients with RPC, current randomized trials included mostly patients with right-sided RPC.

Methods : International multicenter retrospective study including consecutive patients after left-sided pancreatic resection for pathology-proven RPC, either after neoadjuvant therapy or upfront surgery in 76 centers from 18 countries on 4 continents (2013-2019). Primary endpoint is OS from diagnosis. Time-dependent Cox regression analysis was performed to investigate the association of neoadjuvant therapy with OS, adjusting for confounders at time of diagnosis. Adjusted OS probabilities were calculated.

Results : Overall, 2,282 patients after left-sided pancreatic resection for RPC were included of whom 290 patients (13%) received neoadjuvant therapy. The most common neoadjuvant regimens were (m)FOLFIRINOX (38%) and gemcitabine-nab-paclitaxel (22%). After upfront surgery, 72% of patients received adjuvant chemotherapy, mostly a single-agent regimen (74%). Neoadjuvant therapy was associated with prolonged OS compared to upfront surgery (adjusted HR=0.69 [95%CI 0.58-0.83]) with an adjusted median OS of 53 vs. 37 months (P=0.0003) and adjusted 5-year OS rates of 47% vs. 35% (P=0.0001) compared to upfront surgery. Interaction analysis demonstrated a stronger effect of neoadjuvant therapy in patients with a larger tumor (Pinteraction=0.003) and higher serum CA19-9 (Pinteraction=0.005). In contrast, the effect of neoadjuvant therapy was not enhanced for splenic artery (Pinteraction=0.43), splenic vein (Pinteraction=0.30), retroperitoneal (Pinteraction=0.84), and multivisceral (Pinteraction=0.96) involvement.

Conclusions : Neoadjuvant therapy in patients with left-sided RPC was associated with improved OS compared to upfront surgery. The impact of neoadjuvant therapy increased with larger tumor size and higher serum CA19-9 at diagnosis. Randomized controlled trials on neoadjuvant therapy specifically in patients with left-sided RPC are needed.