However, PIK3CA amplification is one of most common genetic alterations in ovarian cancer (23.6–40%) [23], [26], [27], [31] and more importantly, an increase in copy number at chromosomal locus 3q26-qter, which harbors the PIK3CA gene, has been observed in 40% of early-stage ovarian cancers [26], suggesting that PIK3CA amplification might be one of the critical events in OSE transformation. The gene discussed is PIK3CA; the disease is ovarian cancer.