Update of NGS analysis of Italian survey of second tumors in patients with diagnosis of GIST (gastrointestinal stromal tumor).

e23518 Background: In patients with GIST, literature reports a risk of second primary tumors between 4.5% and 33% with different distribution in the worldwide. The network of 7 italian EURACAN centers has collected clinical and molecular features of GIST patients with second primary tumors. Methods: We reviewed the clinical characteristics of 201 patients with GIST and second primary tumors in order to evaluate association between risk of dead and each possible factor, using Kaplan meier curve, log-rank test and Cox model for Hazard Ratio and it’s interval Confidence 95% estimation. Furthermore, NGS analysis ( 56 gene onco panel) in 72 patients with GIST was performed. Results: On the basi…