Purpose: Pancreatic cancer is still associated with a poor outcome and low patient quality of life,
which are mainly attributed to the late detection and requirement of distal pancreatectomy with
extended resection of pancreatic tumors. Therefore, novel strategies for early screening and
precise tumor resection are urgently needed. In this study, we evaluated the feasibility of a lowdensity lipoprotein receptor (LDLR)-targeted small-molecule contrast agent (peptide-22-Cy7) for
early screening with photoacoustic tomography and near-infrared (NIR) imaging as guided
surgical navigation to achieve precise resection.
Procedure: Normal pancreatic cells (HPDE6-C7) and cancer cells (PANC-1) were respectively
used in the in vitro targeting evaluations. The ability of peptide-22-Cy7 for preoperative in vivo
pancreatic tumor detection was investigated in a mouse orthotopic pancreatic cancer model (n =
10) using photoacoustic tomography; 18 tumor-bearing mice were further divided into three
groups for different treatments. After intravenous injection of peptide-22-Cy7, surgical navigation
was conducted through laparotomy. Histopathological analysis was used to further confirm the
tumor area and the state of surgical margins.
Results: Flow cytometry demonstrated that peptide-22 is highly specific to pancreatic cancer
cells, with a fluorescence intensity of approximately 87.3 %. Orthotopic pancreatic tumors with a
size of 4 mm could be accurately detected by photoacoustic tomography. Surgical navigation
effectively achieved R0 resection and minimized the range of resection, which led to increased
body weight of the mice following surgery.