Phase II randomized multicenter trial | SWOG Cooperative Group | Resectable PDAC | JAMA Oncology 2021
**Sohal et al.** Davendra P. S. Sohal
Published in JAMA Oncology, 2021
[PubMed Link](https://pmc.ncbi.nlm.nih.gov/articles/PMC7821078/)
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### Essential Takeaway
SWOG S1505 demonstrated feasibility of perioperative multi-agent chemotherapy in resectable PDAC using either mFOLFIRINOX or gemcitabine/nab-paclitaxel. Although neither regimen achieved the predefined 2-year OS target, the study supported the practicality of perioperative systemic therapy and accelerated broader adoption of neoadjuvant treatment paradigms.
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### Clinical Question
Can modern perioperative chemotherapy regimens be safely and effectively delivered in resectable PDAC, and is either regimen promising for further development?
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### Population
- Resectable PDAC
- ECOG 0–1
- No metastatic disease
Central radiographic review was performed to confirm resectability.
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### Study Design
#### Arm 1 — Perioperative mFOLFIRINOX
- 3 months neoadjuvant mFOLFIRINOX
- Surgery
- 3 months adjuvant mFOLFIRINOX
#### Arm 2 — Perioperative Gemcitabine/Nab-Paclitaxel
- 3 months neoadjuvant gemcitabine/nab-paclitaxel
- Surgery
- 3 months adjuvant gemcitabine/nab-paclitaxel
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### Endpoints
#### Primary Endpoint
2-year overall survival (OS)
#### Secondary Endpoints
- Resection rate
- R0 resection rate
- Pathologic response
- Toxicity/adverse events
- Treatment completion rates
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### Key Results
#### Overall Survival
Neither regimen achieved the predefined 2-year OS target of 58%.
Median OS:
- mFOLFIRINOX:
- 23.2 months
- Gemcitabine/nab-paclitaxel:
- 23.6 months
No meaningful efficacy difference was observed between regimens.
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#### Surgical Outcomes
- High rates of surgical resection were achieved in both groups
- Favorable R0 resection rates were observed following perioperative therapy
These findings demonstrated feasibility of delivering surgery after modern neoadjuvant chemotherapy.
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#### Treatment Completion
A substantial proportion of patients were unable to complete all planned perioperative therapy, highlighting logistical and physiologic challenges of prolonged multimodality treatment.
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### Toxicity
Both regimens demonstrated expected multi-agent chemotherapy toxicities, including:
- neutropenia
- fatigue
- gastrointestinal adverse events
Overall tolerability was considered acceptable in appropriately selected patients.
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### Additional Findings
#### Supported Perioperative Therapy Concepts
SWOG S1505 helped demonstrate that:
- preoperative chemotherapy
- surgery
- postoperative chemotherapy
could be successfully integrated in resectable PDAC.
#### Reinforced Systemic-First Thinking
The study contributed to growing interest in:
- biologic selection
- early systemic disease control
- improved delivery of multi-agent therapy
through perioperative treatment paradigms.
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### Interpretation
SWOG S1505 became an important transitional perioperative PDAC trial because it prospectively evaluated modern systemic regimens within a structured perioperative framework.
Although neither arm met the predefined efficacy target, the study reinforced the growing role of systemic-first treatment strategies and helped normalize perioperative therapy concepts in resectable pancreatic cancer.
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### Important Limitations
#### Phase II Design
- Not powered for definitive regimen comparison
#### No Upfront Surgery Control Arm
- Unable to directly compare against traditional surgery-first management
#### Treatment Attrition
- Many patients were unable to complete full perioperative therapy
#### Highly Selected Population
- Central resectability review
- Fit patients treated at experienced centers
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### Practice Impact
SWOG S1505 supported broader adoption of perioperative systemic therapy strategies in resectable PDAC and reinforced several key principles:
- modern chemotherapy can be delivered preoperatively
- biologic selection is important
- prolonged perioperative treatment remains challenging
Although not independently practice-changing, the trial became an important bridge between traditional adjuvant paradigms and modern neoadjuvant/perioperative strategies.