Surgical treatment of pancreatic neuroendocrine tumors: results and analysis of prognostic factors

Abstract

Pancreatic Neuroendocrine Tumors (PNET) are rare neoplasms with a heterogeneous presentation due to its various subtypes. Although many factors can determine the prognosis, the diagnosis of malignancy is often difficult. Furthermore, the treatment of lesions of benign and uncertain behavior is still controversial. Therefore, further studies may contribute to the development of new criteria to improve the prognosis classifications. Objective: To evaluate the results and prognostic factors of patients with PNET submitted to surgical treatment. Methods: This is an observational analytical retrospective study to evaluate 170 patients with PNET submitted to surgical treatment, and admitted to the Bilio-Pancreatic Surgery Unit from HCFMUSP and ICESP, between 1990 and 2012. We will analyze the medical records and the electronic database: HCMED and Tazy. The following parameters will be recorded: 1) clinical data: date of birth, sex, color, weight, height, ECOG, Karnofsky, the onset of symptoms, diagnosis, familial syndrome, clinical signs, hospital admission, use of somatostatin analogs, chemotherapy (drugs and number of cycles), preoperative risk evaluation (cardiac risk, ASA), comorbidities (hypertension, diabetes, etc.), previous surgeries, date of the surgical procedure, type of surgery, intraoperative bleeding, transfusion of blood products, vasoactive drugs, hypotension, hypoglycemia, hyperglycemia, ICU stay, date of admission, date of discharge, vasoactive drugs, transfusion of blood products in the ICU, intubation time, ICU complications, postoperative complications, postoperative treatment, disease recurrence, date and discharge conditions, date and cause of death. 2) laboratory examination: hemoglobin, leukocytes, platelets, pH, base excess, bicarbonate, glucose, urea, creatinine, bilirubin, AST, ALT, gamma glutamyltransferase, sodium, potassium, chloride, amylase, lipase, glucagon, insulin, C-peptide, VIP, somatostatin, gastrin, chromogranin A, pancreatic polipepetídeo, enolase, chorionic gonadotropin, ghrelin, Ca 19-9, Ca 15-3, intra and postoperative blood tests. 3) imaging examination: echocardiography, abdominal ultrasonography, computed tomography, magnetic resonance, EUS, octreoscan, FDG-PET, arteriography. 4) pathological evaluation: tumor size, surgical margins, perineural and vascular invasion, tumor necrosis, number of mitoses, lymph node metastasis, distant metastasis, Ki-67, cytokeratin-19. 5) staging: TNM and WHO Classification. Statistical analysis: Comparisons between two groups will be performed using the Student t test, Mann-Whitney or Chi-square test. We will analyze the variables associated with disease recurrence and patient survival. The disease-free survival (DFS) and the 5-year disease-specific survival will be analyzed using the Kaplan-Meier method and the univariate and multivariate logistic regression analysis will be performed to identify factors of poor prognosis. P values <0.05 will be considered significant.(AU)