Neoadjuvant Treatment in Resectable Pancreatic Cancer. Is It Time for Pushing on It?

Abstract

Pancreatic resection still represents the only curative option for patients affected by pancreatic ductal adenocarcinoma (PDAC). However, the association with modern chemotherapy regimens is a key factor in improving the inauspicious oncological outcome. The benefit of neoadjuvant treatment (NAT) for borderline resectable/locally advanced PDAC has been demonstrated; this evidence raises the question of whether even resectable PDAC should undergo NAT rather than upfront surgery. NAT may avoid futile surgery because of undetected distant metastases or aggressive tumor biology, providing more effective systemic control of the disease, which is hampered when adjuvant chemotherapy is delayed or precluded. However, recent data show controversial results regarding the efficacy and safety of NAT in resectable PDAC compared to upfront surgery. Although several prospective studies and meta-analyses indicate better oncologic outcomes after NAT, there are some biases, such as the methodological approaches used to capture the events of interest, which could make these results hardly reproducible. For instance, per-protocol studies, considering only the postoperative outcomes, tend to overestimate the performance of NAT by excluding patients who will never be suitable for surgery due to the development of chemotoxicity or tumor progression. To draw reliable conclusions, the studies should capture the events of interest of both strategies (NAT/upfront surgery) from the time of allocation to a specific treatment in an intention-to-treat fashion. This critical review highlights the current literature data concerning the use of NAT in resectable PDAC, summarizing the results of high-quality studies and focusing on the methodological issues of the most recent pieces of evidence.

Keywords: chemotherapy; neoadjuvant treatment; pancreatic adenocarcinoma; resectable pancreatic adenocarcinoma; upfront surgery.

Figure 1

Treatment algorithms for resectable pancreatic cancer reported in the NCCN Guidelines Version 1.2021. (6). RPDC, Resectable pancreatic ductal adenocarcinoma; NAT, neoadjuvant treatments; EUS, endoscopic ultrasound; CT, computed tomography; MRI, Magnetic resonance; MIPS, minimally invasive pancreatic surgery. *High risk patients: Patiens with high risk features in terms of radiological (large primary tumor, large lymphonodes suspected for metastatic) and/or biological findings (Ca 19.9 > 500 U/ml in case of absence of biliary obstruction and/or cholangitis, extreme irradiated pain, excessive weight loss).