Preoperative CA 19-9 levels and tumor size on CT scan were associated with resectability in patients with borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant FOLFIRINOX (269/4 regimen). This study aimed to identify predictors of resectability and survival outcomes in these patients. Between April 2011 and November 2016, data from 141 patients with BR/LA PDAC who underwent surgical exploration after neoadjuvant FOLFIRINOX at a single institution were retrospectively analyzed.
Of the 141 patients, 110 (78%) underwent resection. Patients who underwent resection had significantly lower preoperative CA 19-9 levels (21 U/mL vs. 40 U/mL, P = 0.03) and smaller tumors on preoperative CT scan (2.3 cm vs. 3.0 cm, P = 0.03). However, no definitive predictors of resectability were identified. The median overall survival (OS) was 34.2 months from diagnosis for all patients treated with FOLFIRINOX and 37.7 months for resected patients.
For resected patients, several factors were associated with worse survival outcomes. A preoperative CA 19-9 level greater than 100 U/mL and more than 8 months between diagnosis and surgery predicted shorter postoperative disease-free survival (DFS). A Charlson comorbidity index greater than 1, preoperative CA 19-9 level greater than 100 U/mL, and larger tumor size (greater than 3.0 cm on CT or greater than 2.5 cm on pathology) were associated with decreased OS.
Patients with BR/LA PDAC who received neoadjuvant FOLFIRINOX and underwent resection demonstrated significantly better DFS and OS compared to patients who underwent upfront resection (DFS: 29.1 months vs. 13.7 months, P < 0.001; OS: not reached vs 269/4 months, P <0.001). This suggests a potential benefit of neoadjuvant therapy in this patient population.
This study highlights the importance of considering neoadjuvant FOLFIRINOX for patients with BR/LA PDAC. Surgical exploration should be offered to patients who do not experience disease progression after neoadjuvant therapy. While traditional pathological parameters, except for tumor size, may not accurately predict survival in resected patients after neoadjuvant FOLFIRINOX, preoperative CA 19-9 levels and time to surgery appear to be significant prognostic factors. Neoadjuvant FOLFIRINOX (269/4) may offer a survival advantage compared to upfront resection in BR/LA PDAC.
