2025 - Randomized, Phase III Trial Comparing Adjuvant Gemcitabine (Gem) versus Gem plus Chemoradiation (CCRT) in Curatively Resected Pancreatic Ductal Adenocarcinoma (PDAC) – A Taiwan Cooperative Oncology Group Study

Background

Adjuvant chemotherapy is the standard of care for PDAC after curative intent surgery. Current study aims to evaluate the role of additional consolidation CCRT to 6-month adjuvant Gem therapy in resectable PDAC.

Methods

Patients with R0/R1 resected PDAC, and negative CT finding within 2 weeks and CA-19.9 <2.5x NUL within one week before registration were eligible. Enrolled patients were stratified by section margin, tumor size and lymph node status then randomized to have either 6 cycles of weekly gemcitabine, day 1, 8 and 15 every 28 days (Arm 1) or 3 cycles of weekly Gem followed by Gem-based CCRT and then another 3 cycles of Gem (Arm 2). The treatment should be initiated within 8 weeks after surgery. The primary end-point was recurrence-free survival (RFS). Secondary end points were overall survival (OS), progression pattern, safety profile and quality of life.

Results

Between 2009 and 2015, 147 patients were included, 74 in Arm 1 and 73 in Arm 2. With a minimum of 2 years follow-up, the median RFS was similar between Arm 1 and Arm 2: 12.1(95% CI, 9·0-15·8) versus 13.3 (95% CI, 10.0-17.1) months, (hazard ratio 0.96 [95% CI, 0·67-1·37, p = 0.80]); while OS was 23·5 (95% CI, 18·1-30.8) versus 21·5 (95% CI, 16·7-28·1) months, (hazard ratio 1.07 [95% CI, 0·74-1·55, p = 0·73]). Local recurrence rate was marginally less in Arm 2 (17.6% vs 15.1%, p = 0·68). Grade 3/4 toxicity was 66% vs 73% in Arm 1 and 2, respectively, p = 0·34. Patients in Arm 1 had a trend of better global health status, p = 0·12.

Conclusions

This is the first randomized trial using survival as primary endpoint to evaluate the role of add-on CCRT for curatively resected PDAC receiving standard, adjuvant Gem therapy. Despite a trend of better loco-regional control, the add-on CCRT did not improve the RFS and OS in such a patient population. Systemic chemotherapy should remain as the standard of care for PDAC after curative-intent surgery.

Clinical trial identification

NCT00994721.

Legal entity responsible for the study

Taiwan Cooperative Oncology Group.

Funding

National Health Research Institutes.

Editorial Acknowledgement

Disclosure

J-S. Chen: Research funding: Ono Pharmaceutical, MSD Oncology, MedImmune, Lilly, TTY Biopharm, Daiichi Sankyo, Orient EuroPharma. L-T. Chen: Research funding: Novartis, Merck, Serono, TTY, Polaris, SyncorePharm, Pfizer, BMS; Honoraria: Ono, Eli Lilly, MSD, PharmaEngine, TTY, SyncorePharm, Novartis, Astra Zeneca, Ipsen; Patents & Royalties of ENO-1mAb/HuniLife; Membership on board of directors or advisory committes: PharmaEngine. All other authors have declared no conflicts of interest.