Researchers identified a possible survival benefit with adjuvant chemotherapy for patients with pancreatic ductal adenocarcinoma (PDAC) who had node-negative (N0)-disease following neoadjuvant therapy and surgical resection. The researchers reported their findings in the journal JAMA Surgery.
Neoadjuvant therapy for PDAC typically does not result in complete or near-complete pathologic response, but it has been associated with a greater frequency of N0 resections, compared with surgery without neoadjuvant therapy, the researchers explained in their report. However, whether adjuvant therapy may have additional effects has been unclear.
The study was a retrospective review of records from 2 tertiary care centers. Records for patients with localized PDAC treated using preoperative therapy followed by surgical resection that resulted in N0 disease during the years of 2010 through 2019 were included. Neoadjuvant therapy could include chemotherapy with or without concomitant radiation. Adjuvant therapy could include either gemcitabine-based treatment or FOLFIRINOX, with or without radiation. Outcomes of interest included progression-free survival (PFS), overall survival (OS), and relationships between adjuvant therapy and clinicopathologic variables.
The researchers evaluated 430 patients with N0 disease after resection, mean age 65.2 years (SD, 9.4). Most patients (72.1%) underwent pancreaticoduodenectomy. Among patients who did not have 90-day mortality or unknown 90-day mortality status, adjuvant therapy was given to 51.8%, most often including gemcitabine, and adjuvant radiation was given to 8.9%.
Restricted mean PFS was 4.4 years (95% CI, 3.8-4.9) for patients who received adjuvant therapy vs 3.4 years (95% CI, 2.8-3.8) for patients who did not receive adjuvant therapy (P <.001). Restricted mean OS was 5.4 years (95% CI, 4.9-5.9) vs 4.7 years (95% CI, 4.1-5.2; P =.009), respectively.
Perineural invasion was reported in 59.3% of evaluated patients, lymphovascular invasion was reported in 22.0%, and residual positive margins were reported in 21.1%. In adjusted analyses, perineural invasion, lymphovascular invasion, and poorly differentiated tumors were associated with significantly poorer PFS and OS. However, a benefit of prolonged survival with adjuvant therapy seemed most apparent in patients with perineural invasion (hazard ratio, 0.55; 95% CI, 0.32-0.97; P =.04).
The researchers concluded that, in this study, patients with N0 disease who received neoadjuvant therapy appeared to have a survival benefit with adjuvant therapy, especially those with perineural invasion.
Disclosures: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Hammad AY, Hodges JC, AlMasri S, et al. Evaluation of adjuvant chemotherapy survival outcomes among patients with surgically resected pancreatic carcinoma with node-negative disease after neoadjuvant therapy. JAMA Surg. Published online November 23, 2022. doi:10.1001/jamasurg.2022.5696