On the prevalence of KRAS mutations in GISTs

Abstract

Dear Editor, In our commentary entitled “GISTogram: a graphic presentation of the growing GIST complexity,” recently published in Virchows Archiv [1], on the basis of an extrapolation from a naive GIST cohort from Ticino, Switzerland [2], we proposed a possible 4 % prevalence of KRAS mutations in GISTs. A recent paper by Lasota et al. reported about the absence of KRAS mutations in a large cohort of GISTs (n =514) [3] which, to the best of our knowledge, constitutes by itself about 60% of cases so far studied for this molecular alteration [4–7]. Thus, considering the cumulative evidence produced so far, the actual possible prevalence of KRAS mutations in GISTs seems much lower than the one we hypothesized, possibly approaching 0.3 %.