Laura Miotke, MD, University of Utah School of Medicine, Salt Lake City, discusses results from a study, which evaluated and compared real-world outcomes of recurrent vs de novo metastatic pancreatic adenocarcinoma among patients who receive systemic therapy.
These results were presented at the virtual 2021 ASCO Gastrointestinal Cancers Symposium.
Hi, I'm Dr Laura Miotke. I am an internal medicine resident at the University of Utah, working with the Department of Oncology. It's my pleasure to talk to you today about our work on real‑world outcomes in recurrent vs de novo metastatic pancreatic adenocarcinoma, which we presented at the ASCO GI Meeting 2021.
Our major point in this work is that patients who develop recurrent pancreatic cancer have an improved overall survival compared to those who develop metastatic pancreatic cancer de novo. As you may know, more than 80% of patients with early‑stage pancreatic cancer relapse following surgical resection.
Typically, this population of patients have been excluded from or at least not differentiated from the de novo population in large clinical trials. Our data, though, would imply that this population of patients should be included in those trials that established the current standard of care for palliative systemic therapies.
What we did, we looked at patients who were diagnosed with metastatic or advanced pancreatic cancer between 2014 and 2019 in the Flatiron Health database. This is essentially a deidentified electronic health record‑derived database that originates from about 280 US cancer clinics.
This ended up being about 4000 patients with de novo metastatic disease, compared to about 1000 patients who developed advanced pancreatic cancer following surgery. We then compared overall survival between these 2 groups, which we defined as time from their advanced disease diagnosis to either death or last follow‑up visit.
Then we further stratified the patients in the recurrent group by time from surgery, whether that was more than or less than 6 months. We found that the recurrent patients range from stage 1 to stage 3 at their initial diagnosis, with the majority in stage 2.
In both groups, the head of the pancreas was the most common site of presentation, which made sense. Interestingly, this accounted for a significantly higher proportion of patients in the recurrent group. The CA 19‑9 levels in the de novo group were significantly greater in the recurrent group, which could possibly indicate a higher disease burden in these patients.
Our population also reflected clinical practice in terms of the treatment that patients received as about 50% of patients in each group received gemcitabine and paclitaxel as first‑line, followed by about 20% who received FOLFIRINOX.
Ultimately, the overall survival in the recurrent group was about 11 months, compared to 7 months in the de novo group. This difference was significant both in a univariate and multivariable comparison.
One hypothesis that we had for this was there may be a smaller burden of disease at the time of diagnosis in the recurrent population, which would be supported by the fact that their CA 19‑9 levels were a bit lower.
Additionally, we did not find any significant difference in overall survival, based on time from surgery, whether that was greater than or less than 6 months. This is important, because often, patients who recur within 6 months of surgery are excluded from clinical trials with the apprehension that they may skew the overall survival of the cohort.
Our study may suggest that we include these patients no matter when they recur, as long as they receive a different chemo backbone in the adjuvant or neoadjuvant setting. One of the drawbacks of our study was that we didn't have the information on which chemo backbone they received in the adjuvant or neoadjuvant setting.
Overall, our research would suggest that we can include more patients with recurrent pancreatic cancer in clinical trials, and that when we do include these recurrent patients, we may want to stratify randomization by whether patients were recurrent or de novo, given the fact that there was a difference in overall survival between these 2 populations.