RESUMEN
Adenomas of the breast are rare benign tumors although single cases with malignant behavior have been reported. However, the genetic basis of these tumors is unknown. Employing targeted next generation sequencing of 50 cancer-related genes as well as Sanger sequencing, we profiled a cohort of 18 mammary adenomas comprising 9 ductal, 6 tubular, and 3 lactating adenoma. Missense mutations were detected in 8 of the 18 cases (44%). Specifically, five (56%) ductal adenomas and three (50%) tubular adenomas harbored mutated genes. No mutations were detected in lactating adenomas. Three of the nine ductal adenomas showed mutant AKT1 (p.E17K) with two of them harboring an additional GNAS mutation (p.R201C). One case had mutant PIK3CA (p.H1047R) and another case a mutation in GNAS (p.R201C). The three cases of mutated tubular adenomas showed mutations in either MET or FGFR3. Of note, we did not detect copy number changes and none of the cases including tubular adenomas had mutations in exon 2 of MED12. Our results suggest that ductal adenomas are related to papillomas of the breast and screening for mutations in exon 2 of MED12 might help to facilitate differential diagnosis between tubular adenoma and fibroadenoma in difficult cases. Lastly, our data exemplarily demonstrate that mutations in cancer-related genes per se do not indicate malignancy but occur in benign tumors. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Adenoma/genética , Neoplasias de la Mama/genética , Cromograninas/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Complejo Mediador/genética , Mutación/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Adenoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Neoplasias de la Mama/patología , Fosfatidilinositol 3-Quinasa Clase I , Exones/genética , Femenino , Estudios de Seguimiento , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Lactancia/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Adulto JovenRESUMEN
Papillary hidradenoma (a.k.a. hidradenoma papilliferum) is a benign tumor of the anogenital region that almost exclusively arises in middle-aged Caucasian women. These tumors may recur and rare cases of malignant development have been reported. The genetic basis of papillary hidradenoma is currently unknown. Hence, we employed targeted high-coverage next generation sequencing interrogating 50 cancer-related genes and conventional Sanger sequencing to investigate the mutational landscape in a cohort of 15 cases. Additionally, we analyzed the HPV status of these tumors. Thirteen cases (87%) harbored mutations in cancer-related genes. Recurrent mutations in PIK3CA and AKT1 were present in 10 of the cases (67%). One PIK3CA mutated case had a concomitant STK11 mutation. Three cases harbored mutually exclusive mutations in BRAF, APC and ERBB4. The remaining two cases showed no mutations. None of the cases harbored DNA of human papilloma virus. Our results also provide evidence that--just as BRAF V600E mutations in hyperplastic polyps and benign nevi- a mutated driver gene does not imply malignant behavior per se but may set the basis for malignant transformation. The latter point may explain why rare cases of papillary hidradenoma have been reported to take a malignant course. Lastly, our genetic data may suggest treatment avenues beyond conventional surgery for some of these tumors.