Our study, adopting a PTEN IHC H-score method, provides further support for the role of absent or low expression (H-score, 0 to 4) of PTEN (in 52.4% GISTs) as a predictor of recurrence in patients with primary GIST, although the result was not statistically significant on multivariate analysis. The gene discussed is PTEN; the disease is gastrointestinal stromal tumor.