Background: Concerns exist about a conservative management of well-differentiated nonfunctioning small pancreatic neuroendocrine tumors (NF-PanNET) in young patients and when preoperative Ki67 proliferative index is >= 3%.Aim: To evaluate an association between age, tumor size and grading in patients with sporadic NF-PanNET who underwent curative resection.Methods: Patients who underwent surgery for sporadic NF-PanNET (excluding G3) were retrospectively analyzed. Linear regression analysis was performed to evaluate a possible correlation between continuous variables, whereas multiple logistic regression analysis was performed for determining predictors of NF-PanNET-G2.Results: Overall, 235 patients with NF-PanNET-G1/G2 were included. The median largest radiological diameter was 25 mm. Age correlated neither with tumor size (P = 0.675) nor with Ki67 index (P = 0.376). On multivariate linear regression analysis, factors independently associated with Ki67 index were NF-PanNET size (P = 0.031), perineural invasion (P = 0.004), microvascular invasion (P = 0.001) and necrosis (P = 0.009). The most accurate NF-PanNET size for predicting NF-PanNET-G2 was 25 mm. On multivariate analysis, a NF-PanNET size >25 mm was independently associated with the risk of having a PanNET-G2 (P = 0.025).Conclusion: No correlations exist between age and NF-PanNET size or proliferative index. Therefore, an a priori aggressive attitude is not justified in young patients with small NF-PanNET, as a long-life expectancy is probably unlikely to increase the risk of malignant transformation. (C) 2019 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
The size of well differentiated pancreatic neuroendocrine tumors correlates with Ki67 proliferative index and is not associated with age
Partelli, Stefano;Crippa, Stefano;Zamboni, Giuseppe;
2019-01-01
Abstract
Background: Concerns exist about a conservative management of well-differentiated nonfunctioning small pancreatic neuroendocrine tumors (NF-PanNET) in young patients and when preoperative Ki67 proliferative index is >= 3%.Aim: To evaluate an association between age, tumor size and grading in patients with sporadic NF-PanNET who underwent curative resection.Methods: Patients who underwent surgery for sporadic NF-PanNET (excluding G3) were retrospectively analyzed. Linear regression analysis was performed to evaluate a possible correlation between continuous variables, whereas multiple logistic regression analysis was performed for determining predictors of NF-PanNET-G2.Results: Overall, 235 patients with NF-PanNET-G1/G2 were included. The median largest radiological diameter was 25 mm. Age correlated neither with tumor size (P = 0.675) nor with Ki67 index (P = 0.376). On multivariate linear regression analysis, factors independently associated with Ki67 index were NF-PanNET size (P = 0.031), perineural invasion (P = 0.004), microvascular invasion (P = 0.001) and necrosis (P = 0.009). The most accurate NF-PanNET size for predicting NF-PanNET-G2 was 25 mm. On multivariate analysis, a NF-PanNET size >25 mm was independently associated with the risk of having a PanNET-G2 (P = 0.025).Conclusion: No correlations exist between age and NF-PanNET size or proliferative index. Therefore, an a priori aggressive attitude is not justified in young patients with small NF-PanNET, as a long-life expectancy is probably unlikely to increase the risk of malignant transformation. (C) 2019 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.