Surgical treatment of primary gastrointestinal stromal tumors (GISTs): Management and prognostic role of R1 resections

Background: Surgery represents the best treatment for primary gastrointestinal stromal tumors (GISTs). The aim of this study is to analyse outcomes of surgical management in order to evaluate the influence of microscopically R1 margins on survival and recurrence in patients affected by GISTs. Methods: The study reviewed retrospective data from 74 patients surgically treated for primary GISTs without metastasis at diagnosis. Clinical and pathological findings, surgical procedures, information about follow up and outcomes were analyzed. Results: Recurrence rate was low and no patients died in the R1 group during the follow up period. The difference in recurrence free survival for patients undergoing an R0 (n = 54) versus an R1 (n=20) resections was not statistically significant (76% versus 85% at 3 years, logrank test p-value =0,14; 63% versus 86% at 5 years, logrank test p-value= 0,48) Conclusions: Microscopically positive margin has no influence on overall and relapse-free survival in GIST patients. Thus, when R0 surgery implies major functional sequelae, it may be decided to accept possible R1 margins, especially for low risk tumors.