In a study reported in JAMA Oncology, Mehtsun et al found patterns of increasing use of adjuvant chemotherapy over time among patients aged ≥ 80 years undergoing pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. In addition, they found that use of adjuvant chemotherapy was associated with better overall survival.

As stated by the investigators, “Patients [aged] 80 years and older with pancreatic ductal adenocarcinoma have not consistently received treatments that have established benefits in younger older adults (aged 60 to 79 years), yet patients 80 years and older are increasingly being offered surgery. Whether adjuvant chemotherapy provides additional benefit among patients 80 years and older with pancreatic ductal adenocarcinoma following surgery is not well understood.”

Study Details

The study involved National Cancer Database data on patients aged ≥ 80 years diagnosed with stage I to III pancreatic ductal adenocarcinoma between 2004 and 2016 who underwent pancreaticoduodenectomy. Survival was compared among patients who did vs did not receive adjuvant chemotherapy within 90 days following surgery.

Key Findings

Between 2004 and 2016, 2,569 patients (median age = 82 years, interquartile range = 81–84 years; 55% women) underwent surgery for pancreatic ductal adenocarcinoma. Of these, 1,217 (47.4%) received adjuvant chemotherapy. The use of adjuvant chemotherapy increased by an absolute 18.6% (95% confidence interval [CI] = 8.0%­–29.0%, P = .001) between 2004 and 2016, from approximately 37% to 56%.

Median overall survival was 17.2 months (95% CI = 16.1–19.0 months) among patients receiving adjuvant chemotherapy vs 12.7 months (95% CI = 11.8–13.6 months) among those not receiving adjuvant chemotherapy (hazard ratio [HR] = 0.72, 95% CI = 0.65–0.79, P < .001). In a propensity score-matched analysis, the hazard ratio favoring adjuvant chemotherapy was 0.74 (95% CI = 0.67–0.83, P < .001). Similar findings were made in subgroup analyses according to node-negative, margin-negative, clinically complex, node-positive, and margin-positive disease.

In multivariate analysis, receipt of adjuvant chemotherapy (HR = 0.72, 95% CI = 0.65–0.79, P < .001), female sex (HR = 0.88, 95% CI = 0.80–0.96, P < .001), and surgery performed from 2011 to 2016 vs earlier years (HR = 0.90, 95% CI = 0.82–0.99, P = .02) were associated with improved overall survival.  

Poorer overall survival was associated with higher pathologic stage (HRs = 1.68, 95% CI = 1.43–1.97, P < .001 for stage II and 2.39; 95% CI = 1.88–3.04, P < .001 for stage III vs stage I), positive surgical margins (HR = 1.49, 95% CI =1.34–1.65, P < .001), length of hospital stay longer than the median of 10 days (HR = 1.17, 95% CI = 1.07–1.28, P < .001), and receipt of oncologic care at nonacademic facilities (HR = 1.20, 95% CI = 1.07–1.35, P < .001 for community cancer programs; HR = 1.25, 95% CI = 1.07–1.46, P < .001 for integrated network cancer programs vs academic facilities).

The investigators concluded, “In this cohort study, the use of adjuvant chemotherapy among patients who underwent resection for pancreatic ductal adenocarcinoma increased over the study period, yet it still was administered to fewer than 50% of patients overall. Receipt of adjuvant chemotherapy was associated with a longer median survival.”

Winta T. Mehtsun, MD, MPH, of the Division of Surgical Oncology, University of California San Diego, is the corresponding author for the JAMA Oncology article.

Disclosure: For full disclosures of the study authors, visit jamanetwork.com.