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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Adenocarcinoma, Adolescent, Adult, Aged, Aged, 80 and over, Female, Follow-Up Studies, Humans, Lymphatic Metastasis, Male, Middle Aged, Neoplasm Invasiveness, Pancreatectomy, Pancreatic Neoplasms, Pancreaticoduodenectomy, Retrospective Studies, Risk Factors, Survival Analysis, Treatment Outcome, Young Adult.
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Do tumor-positive resection margins reflect an aggressive tumor biology in pancreatic cancer? Context: Resection margin status has been shown to impact outcomes for pancreatic adenocarcinoma (PAC), yet it remains unknown whether margin status is a reflection of tumor biology or surgical technique. Two hundred eighty-three consecutive patients with pancreatic adenocarcinoma were identified in a prospectively maintained database. Only patients with R0 (n = 207) or R1 (n = 76) tumors were included. Each operative surgeon's first 50 cases were excluded to control for technical inexperience. Univariable and multivariable analyses of clinicopathologic and intra-operative factors were performed. The median follow-up for the cohort was 30.3 months with a median overall survival (OS) of 19.0 months. The R1 group had a higher rate of lymph node ratio >0.2 (41% vs. 25%; P = 0.013), and more microvascular invasion (64% vs. 44%; P = 0.007). R0 resections had both improved overall survival (22.7 months vs. 15.0 months, P = 0.004) and disease free survival (13.5 months vs. 10.7 months, P = 0.026). Factors independently associated with overall survival were microvascular invasion (HR 2.26; P = 0.001), pre-existing pulmonary disease (HR 2.18, P = 0.043), and cardiac disease (HR 1.78, P = 0.033).
assistant
Factors associated with an R1 resection reflect a biologically more aggressive tumor, with a higher likelihood of microvascular invasion and increased positive lymph node ratio. Final Decision: yes