Disparity in use of modern combination chemotherapy associated with facility type influences survival of 2655 patients with advanced pancreatic cancer

Exploring external validity of chemotherapy for pancreatic ductal adenocarcinoma in real life

INTRODUCTION

Cisplatin, nab-paclitaxel, capecitabine, and gemcitabine (PAXG) regimen activity was assessed in a single institution phase II trial (PACT-19) on pancreatic ductal adenocarcinoma (PDAC). The PACT-31 study explored the external validity of PACT-19 results.

MATERIALS AND METHODS

Patients aged ≥18 and ≤75 years with KPS ≥70, and PDAC diagnosis receiving PAXG in the participating institutions were eligible and categorized as follows: A) PACT-19; B) PACT-31-HSR; C) PACT-31-non-HSR. With a sample of 175 patients, assuming a target 1-year overall survival of 60 % for metastatic and of 80 % for non-metastatic patients, the trial will be considered successful with the 1-year OS falling into the 95 % CI.

RESULTS

Data from 68 PACT-19 and 168 PACT-31 patients were retrieved. After 124 events, 1yOS was 52.5 % (95 %CI: 44.6-60.4 %) for metastatic and 80.5 % (95 %CI: 71.9-89.1 %) for non-metastatic patients. Survival overlapped between PACT-19 and PACT-31-HSR (median 17.6 and 17.4 months, p = 0.21) and was significantly shorter in PACT-31-non-HSR (median 11.3 months; p = 0.03). Differences of dose-intensity, use of maintenance therapy, and treatment after progression between PACT-31-HSR and non-HSR were evidenced.

DISCUSSION

PACT-19 results have external validity. The outcome difference between HSR and non-HSR centers endorses the need of creating a hub-and-spoke network aimed at sharing the expertise on rare-diseases.

Effect of surgery versus chemotherapy in pancreatic cancer patients: a target trial emulation

BACKGROUND

To estimate the causal effect of surgery vs chemotherapy on survival in patients with T1-3NxM0 pancreatic cancer in a rigorous framework addressing selection bias and immortal time bias.

METHODS

We used population-based Danish health-care registries to conduct a cohort study emulating a hypothetical randomized trial to estimate the absolute difference in survival, comparing surgery with chemotherapy. We included pancreatic cancer patients diagnosed during 2008-2021. Exposure was surgery or chemotherapy initiated within a 16-week grace period after diagnosis. At the time of diagnosis, data of each patient were duplicated; one copy was assigned to the surgery protocol, and one copy to the chemotherapy protocol of the hypothetical trial. Copies were censored when the assigned treatment deviated from the observed treatment. To account for informative censoring, uncensored patients were weighted according to confounders. For comparison, we also applied a more conventional analysis using propensity score-based inverse probability weighting.

RESULTS

We included 1744 patients with a median age of 68 years: 73.6% underwent surgery, and 18.6% had chemotherapy without surgery; 7.8% received no treatment. The 3-year survival was 39.7% (95% confidence interval [CI] = 36.7% to 42.6%) after surgery and 22.7% (95% CI = 17.7% to 28.4%) after chemotherapy, corresponding to an absolute difference of 17.0% (95% CI = 10.8% to 23.1%). In the conventional survival analysis, this difference was 23.0% (95% CI = 17.0% to 29.0%).

CONCLUSION

Surgery was superior to chemotherapy in achieving long-term survival for pancreatic cancer. The difference comparing surgery and chemotherapy was substantially smaller when using the clone-censor-weight approach than conventional survival analysis.

A randomized phase II study of full dose gemcitabine versus reduced dose gemcitabine and nab-paclitaxel in vulnerable patients with non-resectable pancreatic cancer (DPCG-01)

BACKGROUND

According to current evidence, the best treatment for fit patients with non-resectable pancreatic cancer (PC) is combination chemotherapy, whereas frail patients are recommended gemcitabine (Gem) monotherapy. Randomized controlled trials in colorectal cancer and a post-hoc analysis of gemcitabine and nab-paclitaxel (GemNab) in PC suggest, however, that reduced dose of combination chemotherapy may be feasible and more efficient compared to monotherapy in frail patients. The aim of this study is to investigate whether reduced dose GemNab is superior to full dose Gem in patients with resectable PC, who are not candidates for full dose combination chemotherapy in first line.

METHODS

The Danish Pancreas Cancer Group (DPCG)-01 trial is a national multicenter prospective randomized phase II trial. A total of 100 patients in ECOG performance status 0-2 with non-resectable PC, not candidate for full dose combination chemotherapy in first line, but eligible for full dose Gem, will be included. Patients are randomized 1:1 to either full dose Gem or GemNab in 80% of recommended dose. The primary endpoint is progression-free survival. Secondary endpoints are overall survival, overall response rate, quality of life, toxicity and rate of hospitalizations during treatment. The correlation between blood inflammatory markers, including YKL-40 and IL-6, circulating tumor DNA, and tissue biomarkers of resistance to chemotherapy and outcome will be explored. Finally, the study will include measures of frailty (G8, modified G8, and chair-stand-test) to assess whether scoring would enable a personalized allocation to different treatments or indicates a possibility for interventions.

DISCUSSION

Single-drug treatment with Gem has for frail patients with non-resectable PC been the main treatment option for more than thirty years, but the impact on outcome is modest. If improved results and sustained tolerability with reduced dose combination chemotherapy can be shown, this could change the future practice for this increasing group of patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05841420. Secondary Identifying No: N-20210068. EudraCT No: 2021-005067-52.

PROTOCOL VERSION

1.5, 16-MAY-2023.

Trends in pancreatic cancer incidence, characteristics, and outcomes in Denmark 1980-2019: A nationwide cohort study

OBJECTIVE

To describe time-trends in incidence, characteristics, treatments, and survival in pancreatic cancer patients in Denmark during 1980-2019.

DESIGN

A nationwide population-based cohort study of all Danish patients diagnosed with exocrine pancreatic cancer during the study period. Data was obtained from individual-level cross linkage between Danish healthcare registries. We present descriptive characteristics and survival estimates, which was obtained using the Kaplan-Meier estimator and Cox proportional hazards regression models.

RESULTS

During the study period, 32,107 patients were diagnosed with pancreatic cancer. In the most recent period, the age-standardized incidence rate was 17.7 per 100,000 person-years. Throughout the study period, between 18.4% and 27.5% of patients had no tumor staging performed, and approximately half of the patient were only offered best supportive care. The proportion of patients treated with surgery doubled during the study period, and the use of adjuvant and neoadjuvant oncological therapy increased substantially. Median survival after surgical resection also increased to 25.8 months in the most recent time period.

CONCLUSION

Pancreatic cancer incidence is increasing in Denmark, and this increase is projected to continue. The proportion of patients offered curative-intent treatment increased, which translates into an increase in overall survival. All numbers are comparable to best international standards.