title: Frequent PIK3CA-activating mutations in hidradenoma papilliferums.
abstract: Hidradenoma papilliferum (HP) is a benign epithelial tumor most commonly seen in the vulva. It is proposed to be derived from the anogenital mammary-like glands and is histologically very similar to the mammary intraductal papilloma (IP). Approximately 60% of mammary IPs have activating mutations in either PIK3CA or AKT1, with each gene accounting for 30% of cases. In this study, we screened the mutation statuses of PIK3CA, AKT1, RAS, and BRAF in 30 HPs. The results showed that activating mutations in either PIK3CA or AKT1 were identified in 20 tumors (67%); 19 tumors had PIK3CA mutations (63%; 13 in exon 20 and 6 in exon 9), and 1 had an AKT1 E17K mutation (3%). BRAF V600E mutation was found in an HP that also had a PIK3CA H1047R mutation. No RAS mutation was found. The mutation status was not correlated with the degree of epithelial cell hyperplasia. We conclude that although there might be site-related variations in the mutation frequencies of PIK3CA and AKT1 genes, HP is histologically and also genetically very similar to the mammary IP, suggesting that HP can be viewed as the extramammary counterpart of mammary IP.
authors.affiliation: Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan; Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei 10051, Taiwan.
authors.forename: Jau-Yu
authors.initials: JY
authors.lastname: Liau
authors.affiliation: Department of Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan.
authors.forename: Jui
authors.initials: J
authors.lastname: Lan
authors.affiliation: Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan.
authors.forename: Jin-Bon
authors.initials: JB
authors.lastname: Hong
authors.affiliation: Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan; Graduate Institute of Pathology, National Taiwan University College of Medicine, Taipei 10051, Taiwan.
authors.forename: Jia-Huei
authors.initials: JH
authors.lastname: Tsai
authors.affiliation: Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan.
authors.forename: Kuan-Tin
authors.initials: KT
authors.lastname: Kuo
authors.affiliation: Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan.
authors.forename: Chia-Yu
authors.initials: CY
authors.lastname: Chu
authors.affiliation: Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan.
authors.forename: Yi-Shuan
authors.initials: YS
authors.lastname: Sheen
authors.affiliation: Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei 11696, Taiwan. Electronic address: bluemage@pchome.com.tw.
authors.forename: Wen-Chang
authors.initials: WC
authors.lastname: Huang
mesh_terms: D018250:Acrospiroma / Q000201:enzymology / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D058534:Class I Phosphatidylinositol 3-Kinases; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D005787:Gene Frequency; D011905:Genes, ras; D020022:Genetic Predisposition to Disease; D006801:Humans; D006965:Hyperplasia; D008875:Middle Aged; D009154:Mutation; D010641:Phenotype; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics*; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics; D013544:Sweat Gland Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D014846:Vulvar Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor; D019869:Phosphatidylinositol 3-Kinases; D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human; C494918:AKT1 protein, human; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D051057:Proto-Oncogene Proteins c-akt
keywords: AKT1; Anogenital mammary–like glands; Hidradenoma papilliferum; Intraductal papilloma; PIK3CA