Pancreatic ductal adenocarcinoma (PDAC) is the most common epithelial exocrine pancreatic malignancy, accounting for 90% of the malignant neoplasm of the pancreas (1). PDAC is a very aggressive tumor with a poor 5-year survival of less than 10%. It is characterized by early lymphatic and vascular spread, as well as aggressive local infiltration. The current standard treatment for resectable tumors is surgery followed by adjuvant chemotherapy(2).
According to the NCCN definition, a tumor is considered to be resectable if no distant metastasis, no local signs of invasion or abutment of major vessels are seen on preoperative CT or MRI(2). The tumor is classified as borderline resectable when no distant metastasis is to be seen, the invasion of the superior mesenteric vein or portal vein allows safe resection and reconstruction, the invasion of the superior mesenteric artery does not exceed 180° of the circumference and the tumor does not invade the celiac trunk(2). The tumor is seen as not resectable when the conditions for clearly or borderline resectable are not fulfilled(2).
In the literature, 16 to 85% of the resected tumors have an incomplete tumor resection (R1 status) (3), whereby the large range is related to the pathological processing and the used definition for R1. This means that an important number of patients will undergo an operation with an increased risk for early tumor recurrence, and subsequently, a shortened long-term survival.
The best way to increase survival in patients at risk for an incomplete tumor resection would be to offer them a neoadjuvant treatment in order to increase the R0 resection rate, as such therapy has proven to be effective to downstage locally advanced PDAC (4). However, it remains difficult to preoperatively predict the R status; consequently, it would be crucial to find preoperative criteria to precisely predict surgical resection margins in order to select patient for neoadjuvant treatments.