The size of well differentiated pancreatic neuroendocrine tumors correlates with Ki67 proliferative index and is not associated with age

Stefano Partelli, Francesca Muffatti, Paola Maria Vittoria Rancoita, Valentina Andreasi, Gianpaolo Balzano, Stefano Crippa, Claudio Doglioni, Corrado Rubini, Giuseppe Zamboni, Massimo Falconi

Research output: Contribution to journalArticlepeer-review

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.

Original languageEnglish
Pages (from-to)735-740
Number of pages6
JournalDigestive and Liver Disease
Volume51
Issue number5
DOIs
Publication statusPublished - May 2019

Keywords

  • Grading
  • Pancreatic neuroendocrine neoplasms
  • Tumor size

ASJC Scopus subject areas

  • Hepatology
  • Gastroenterology

Fingerprint Dive into the research topics of 'The size of well differentiated pancreatic neuroendocrine tumors correlates with Ki67 proliferative index and is not associated with age'. Together they form a unique fingerprint.

Cite this