Clinical Research Directory

Detection of Circulating Tumor Cells for the Diagnostic of Pancreatic Adenocarcinoma.

Histological proof is a crucial and necessary step for appropriate care in oncology. In the case of pancreatic cancer, histological proof from pathological analysis of the surgical specimen is very rare due to the limited number (15-20 %) of localized tumor accessible to surgical resection. In most cases, invasive endoscopic explorations are necessary for histological diagnosis before deciding of the most appropriate treatment (palliative chemotherapy or radiochemotherapy). The endoscopic ultrasound with fine needle aspiration (EUS-FNA) is currently considered as the first-line endoscopic procedure for the cytological diagnosis of solid pancreatic tumors. The technique is performed under general anesthesia with sensitivity for the diagnosis of adenocarcinoma of 80% in case of a single procedure and 92% in situations where three different procedures are required. EUS-FNA has to be performed by a physician properly trained for this type of interventional endoscopy. Some severe complications may occur but are relatively rare in expert centers (bleeding, perforation, complications of general anesthesia ...). Diagnostic alternative approach is biological with research in the peripheral blood of markers of tumor disease. It is possible to detect indirect markers which are molecules produced by tumor tissue (eg CA19.9) and direct markers which reflect the presence of tumor biological material (circulating tumor cells (CTCs) or circulating tumor DNA). The value of detection of CTCs is not determined for the diagnostic and therapeutic management of pancreatic cancer. Indeed, no study has evaluated the diagnosis performance of circulating markers with EUS-FNA, the reference method for the diagnosis of unresectable forms.

Neutrophil-to-lymphocyte Ratio and CA 19.9 as Predictors of Perineural Invasion in Pancreatic Cancer

Pancreatic cancer has an incidence of 1,401,450 new cases diagnosed annually worldwide and is the third leading cause of cancer-related death in Spain. This disease is associated with a poor prognosis, reflected by a 5-year survival rate of less than 5% when all stages are grouped together. Several prognostic factors for pancreatic cancer have been identified. The most relevant include preoperative levels of carbohydrate antigen 19-9 (CA 19.9), surgical margins after resection, venous and/or arterial vascular involvement, and histopathological features such as affected locoregional lymph nodes, or perineural and lymphovascular invasion. Among all these factors, perineural invasion may be the primary independent factor affecting prognosis, particularly in patients with relatively favorable pathological features. The identification of perineural invasion before surgery could influence the clinical management of these patients. It may facilitate risk stratification, allowing the identification of patients who would benefit most from neoadjuvant treatments or more aggressive surgical procedures, such as vascular resections. However, perineural involvement is very difficult to detect preoperatively. Only a few studies have analyzed the possible relationship between CA 19.9 and perineural invasion, and their results are inconsistent. Alternatively, some studies have demonstrated the utility of preoperative multidetector computed tomography in detecting extrapancreatic perineural invasion. However, these radiological tests are still not useful for directly detecting microscopic perineural invasion, especially in early stages. On the other hand, in recent years, evidence has supported that the systemic inflammatory response may play an important role in the prognosis of different malignancies. Among these inflammatory markers, the neutrophil-to-lymphocyte ratio (NLR) has gained prominence. Regarding pancreatic cancer, many studies suggest that elevated preoperative NLR levels are associated with a worse prognosis. However, no studies have yet been published analyzing a possible relationship between this inflammatory marker and perineural invasion. The main objective of this study is to correlate the neutrophil-to-lymphocyte ratio (NLR) and CA 19.9 with histopathologically confirmed perineural invasion and, in this way, investigate these data as potential preoperative markers of perineural invasion in pancreatic cancer. Our working hypothesis is that preoperative NLR and CA 19.9 are potential markers of perineural invasion. As secondary objectives, we aim to study the effect of neoadjuvant therapy on inflammatory markers (NLR) and tumor markers (CEA and CA 19.9) in pancreatic cancer.