In ovarian cancer, HER2 positivity varies considerably (8–66%) and specific data regarding the clear cell histotype is limited, with 14–67% HER2 positivity being reported in small patient cohorts (often < 10); no clinical data of antiHER2 therapy in OCCC are available and results of the antiHER2 therapy benefit are inconsistent [8]. This evidence concerns the gene ERBB2 and ovarian carcinoma.