In a retrospective cohort study reported in JAMA Surgery, Hammad et al found that adjuvant therapy was associated with better outcomes vs no adjuvant therapy in patients with node-negative disease after neoadjuvant therapy and resection of pancreatic carcinoma.
The study used data from prospectively maintained pancreatic cancer databases on 430 consecutive patients treated between 2010 and 2019 at University of Pittsburgh Medical Center and Medical College of Wisconsin who had N0 disease after neoadjuvant therapy and surgical resection. Neoadjuvant therapy consisted of chemotherapy with gemcitabine- or fluorouracil-based regimens, received by all patients; a total of 64.9% of patients received concomitant neoadjuvant radiation therapy with stereotactic body radiotherapy (SBRT) or intensity-modulated radiation therapy (IMRT). A total of 217 patients (51.8%) received adjuvant chemotherapy, consisting of gemcitabine-based therapy or FOLFIRINOX (fluorouracil, leucovorin, irinotecan, oxaliplatin); 8.9% of these patients received adjuvant radiotherapy (SBRT or IMRT).
A total of 11 patients with 90-day mortality or unknown 90-day mortality status were excluded from the analyses of progression-free and overall survival; an additional 6 patients were excluded from progression-free survival analysis due to missing recurrence status or progression-free survival time.
Restricted mean progression-free survival was 4.4 years (95% confidence interval [CI] = 3.8–4.9 years) among 214 patients in the adjuvant therapy group vs 3.4 years (95% CI = 2.8–3.8 years) among 199 patients in the no adjuvant therapy group (P < .001).
Restricted mean overall survival was 5.4 years (95% CI = 4.9–5.9 years) among 217 patients in the adjuvant therapy group vs 4.7 years (95% CI = 4.1–5.2 years) among 202 patients in the no adjuvant therapy group (P = .009).
The overall survival benefit of adjuvant therapy was pronounced among patients who did not receive neoadjuvant radiation therapy (5.1 vs 2.0 years, P < .001) and reduced but significant among those who received neoadjuvant radiation therapy (5.1 vs 3.8 years, P = .02). Adjuvant therapy was associated with a significant overall survival benefit among 254 patients with perineural invasion (5.3 vs 3.5 years, P < .001) but not in those without perineural invasion (5.7 vs 6.0 years, P = .84).
On multivariate analysis among all patients, poorer progression-free survival and overall survival were observed among patients with perineural invasion (hazard ratios [HRs] = 2.04, P < .001, and 1.68, P = .009), lymphovascular invasion (n = 92; HRs = 1.47, P = .01, and 1.54, P = .01), and poorly differentiated tumors (n = 61; HRs = 1.90, P = .008, and 1.98, P = .008).
The investigators concluded, “The findings of this cohort study suggest a survival benefit for adjuvant therapy in patients with N0 disease after neoadjuvant therapy and surgical resection. This survival benefit may be most pronounced in patients with perineural invasion.”
Amer H. Zureikat, MD, of the Division of Surgical Oncology, University of Pittsburgh Medical Center, is the corresponding author for the JAMA Surgery article.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.