Surgical Outcome Results From SWOG S1505: A Randomized Clinical Trial of mFOLFIRINOX Versus Gemcitabine/Nab-paclitaxel for Perioperative Treatment of Resectable Pancreatic Ductal Adenocarcinoma.

OBJECTIVE

The optimal neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma (PDA) and the impact on surgical outcomes remains unclear.

METHODS

S1505 (NCT02562716) was a randomized phase II study of perioperative chemotherapy with mFOLFIRINOX (Arm 1) or gemcitabine/nab-paclitaxel (Arm 2). Measured parameters included resection rate, margin positivity, pathologic response, and toxicity.

RESULTS

Between 2015 and 2018, 147 patients were randomized. Of these, 44 (30%) were deemed ineligible (43 by central review). Of the 103 eligible patients, 77 (76%) completed preoperative therapy and underwent surgery; reasons patients did not undergo surgery included toxicity related to preoperative therapy (n = 9), progression (n = 9), or other (n = 7). Of the 77, 73 (95%) underwent successful resection; 21 (29%) required vascular reconstruction, 62 (85%) had negative (R0) margins, and 24 (33%) had a complete or major pathologic response to therapy. The grade 3-5 postoperative complication rate was 16%. Of the 73 patients completing surgery, 57 (78%) started and 46 (63%) completed postoperative therapy. This study represents the first prospective trial evaluating modern systemic therapy delivered in a neoadjuvant/perioperative format for resectable PDA.

CONCLUSIONS

We have demonstrated: (1) Based on the high percentage of enrolled, but ineligible patients, it is clear that adherence to strict definitions of resectable PDA is challenging; (2) Patients can tolerate modern systemic therapy and undergo successful surgical resection without prohibitive perioperative complications; (3) Completion of adjuvant therapy in the perioperative format is difficult; (4) Major pathologic response rate of 33% is encouraging.