Although this heterogeneity was anticipated based on the preclinical data used as a basis for this study (8 of 13 SS patients had overexpression of FZD10, 4/13 had detectable expression and one patient had no detectable FZD10 in the initial study by Nagayama et al. [3]), its importance was underestimated. This evidence concerns the gene FZD10 and synovial sarcoma.