Pancreatic Resection After Neoadjuvant Treatment

Abstract

Pancreatic cancer has a very poor prognosis, with the projection to be the second leading cancer-related death in 2020 [1]. Pancreatic cancer can be divided in three stages: resectable (15%), locally advanced (35%) and metastatic disease (50%) [2]. The diagnosis of resectable and locally advanced pancreatic cancer is determined by the tumor invasion of critical structures, in particular the portal vein, superior mesenteric vein, coeliac artery and superior mesenteric artery. This tumor invasion is usually assessed by contrast enhanced computed tomography (CT). There are several definitions for resectable and locally advanced disease, usually based on the tumor burden of the surrounding major vessels. This tumor burden can be defined as no invasion at all to the surrounding structures (resectable disease) and too much invasion in the surrounding structures to be deemed resectable (locally advanced disease). In between these two extremes there is a diagnostic gap where a tumor has some vessel involvement but is still resectable, this gap is called borderline resectable disease. The two most commonly used definitions for (borderline) resectable disease and locally advanced disease are that of National Comprehensive Cancer (NCCN) and the combined definition of Americas Hepato-Pancreato-Biliary Association (AHPBA), the Society of Surgical Oncology (SSO), and the Society for Surgery of the Alimentary Tract (SSAT) [3, 4]. Both the definitions of NCCN and AHPBA/SSO/SSAT for borderline resectable and locally advanced disease are summarized in Table 20.1. For decades, the primary treatment for borderline resectable pancreatic cancer was upfront surgery. However, neoadjuvant therapy is becoming more and more a valuable upfront therapy for borderline resectable disease. Although there is no clear level I evidence for this treatment [5]. The main purpose of neoadjuvant treatment are threefold: (1) improve probability of radical resection, (2) patient selection of patients with rapid disease progression that will undergo unnecessary surgery, (3) early treatment of occult metastasis and finally more patients receiving systemic treatment since a significant portion of patient do not come to adjuvant therapy after surgical resection due to morbidity [6]. In contrary, locally advanced pancreatic cancer is conventionally treated with induction chemotherapy and sometimes followed by local therapy such as (chemo)radiotherapy or local ablation. Surgery is not recommended as an upfront treatment in locally advanced unresectable pancreatic cancer and is only reserved for patients with disease response and after tumor downstaging with chemotherapy and or (chemo)radiotherapy [7]. In this chapter, an overview will be given of studies that examined the effect of neoadjuvant treatment on surgical outcomes in borderline resectable and locally advanced unresectable pancreatic cancer. Lastly, an illustrative case report will be presented of a patient with locally advanced unresectable pancreatic cancer.