A targeted NGS analysis was performed on all the four different lesions (NEC, endometrioid carcinoma, ovarian endometriosis, and uterine EAH) and on a sample of normal tissue for comparison using the Human Actionable Solid Tumor Mutations QIAseq DNA Panel (DHS-101Z, Qiagen, Hilden, Germany) that analyses 22 oncogenes (BRAF, PDGFRA, EGFR, KRAS, NRAS, KIT, AKT1, ALK, CTNNB1, ERBB3, ESR1, FOXL2, GNA11, GNAQ, IDH1, IDH2, MET, RAF1, RET, ERBB2, PIK3CA, and TP53). This evidence concerns the gene PIK3CA and neuroendocrine carcinoma.