Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and deadly types of
cancer. It often develops without clear symptoms and is usually diagnosed at a late
stage, when treatment options are limited. Even when surgery is possible, the cancer
often returns. Current imaging methods like contrast-enhanced CT (ceCT) and MRI are
useful tools but have important limitations. They may not clearly show the edges of the
tumor, may miss small areas where the cancer has spread, and can be unreliable after
chemotherapy, when inflammation can interfere with image interpretation.
This study focuses on a new imaging method called 68Ga-FAPI-46 PET/CT. This technique
uses a tracer that attaches to a protein called FAP (fibroblast activation protein),
which is found in high amounts in the tissue that supports the growth and spread of
pancreatic tumors. These supporting cells, called cancer-associated fibroblasts (CAFs),
help the tumor grow, invade nearby tissue, and avoid the immune system. By targeting this
protein, the technique can provide highly detailed images of the tumor and the area
around it.
Unlike standard PET/CT scans that use sugar-based tracers (such as 18F-FDG), FAPI PET/CT
does not rely on the tumor's sugar use to detect it. This is important because many
pancreatic tumors do not show up well with FDG scans due to their low activity level.
Instead, the FAPI scan focuses on the surrounding tissue that often reacts strongly to
the presence of cancer, offering a more complete and accurate picture.
In this prospective study, 20 adult patients with confirmed pancreatic cancer scheduled
for surgery will be recruited at Lausanne University Hospital (CHUV). Each participant
will receive a single intravenous injection of the 68Ga-FAPI-46 tracer, with the amount
based on their body weight. After about 60 minutes, a low-dose PET/CT scan will be
performed, taking around 20 minutes. Patients will need to fast for a few hours and drink
water before the scan, but no special contrast agents will be used.
After the scan, patients will receive a follow-up call within a few days to check for any
side effects. Previous studies have shown that this scan is very well tolerated, with no
major side effects reported. Participation in this study will not interfere with any of
the patient's normal care or treatment decisions.
The main aim of the study is to compare the results of the FAPI PET/CT scan with those of
traditional imaging (CT and MRI) to see which gives better information about the size,
shape, and spread of the tumor. Tissue samples collected during surgery will be used to
confirm whether what the scan showed matches what is found in real tissue. This will help
researchers understand how accurate and useful the scan really is.
Secondary goals include checking whether this technique can show if the cancer has spread
to nearby lymph nodes or other organs. It may also help identify areas around the tumor
that are more likely to lead to future cancer spread. Knowing this can help in planning
surgery and follow-up treatment more precisely.
The study also includes exploratory goals, such as examining the presence of FAP-positive
fibroblasts in the removed tissue and how they relate to the PET's results. We hope this
will help us learn more about how the cancer behaves and spreads, which could help
improve care in the future.
This pilot study will run for about two years. If successful, the results could support
the use of 68Ga-FAPI-46 PET/CT as a new standard imaging tool for pancreatic cancer. It
may allow for earlier and more accurate diagnosis, better surgical planning, and more
personalized treatment decisions. In the future, this imaging technique could also be
used for other cancers that involve the same protein, helping more patients benefit from
better imaging and care.
