MUTATION OF BRCA1 GENE IN YOUNG WOMAN WITH BREAST CANCER

CABERO, F.V. (Serviço de Mastologia, Hospital Materno Infantil -), CONDE, D.M. (Serviço de Mastologia, Hospital Materno Infantil -), SILVA, E. P. S. (Serviço de Mastologia, Hospital Materno Infantil -), FERREIRA, R. B. (Serviço de Mastologia, Hospital Mat

Serviço de Mastologia, Hospital Materno Infantil – Goiânia, GOPurpose: To report a case of mutation of the BRCA1 gene in a young woman with breast cancer. Case report: Woman, 24 years old, with complaint of left breast nodule three weeks ago. No previous gestation, on oral contraceptive use. Family history: one case of breast cancer at age 80 and one case of ovarian cancer at age 70 in paternal great-aunt, respectively. Physical examination: mobile nodule, hardened, about 2.0 cm in left breast, negative axilla. Ultrasonography: round nodule with posterior acoustic reinforcement and macrolobulations, measuring 1.3cm. Core-biopsy was performed with histopathological examination demonstrating invasive ductal carcinoma (ICD) GIII. Immunohistochemistry: RE + 1, PR + 1, HER2 + 1, Ki67: 50%. Patient referred for genetic counseling. The genetic test identifies a deleterious mutation on BRCA1 gene, deletion of cytosine at position 5264 that creates a stop codon in the protein. Considering the family history, the genetic test was performed on the patient’s father, being identified the same mutation. Patient submitted to bilateral adenomastectomy with immediate reconstruction with prosthesis, and sentinel lymph node biopsy to the left. Histopathological examination showed ICD, 1.9 cm, GIII and negative sentinel lymph node. Patient underwent adjuvant chemotherapy. It is in use of tamoxifen, and has not relapsed for three years. Conclusions: this is a case of mutation of the BRCA1 gene in a young woman with breast cancer. The patient presents indication of genetic counseling, considering the age as a criterion. The identified mutation is quite dysfunctional, eliminating the BRCT dimerization site, which is essential for the dimerization of the BRCA1 protein. The chance of breast cancer in the carriers of this mutation is 70% and of ovary 35%. Oophorectomy should be considered after 40 years of age, when the case of ovarian cancer is initiated in carriers of the mutation   BRCA1, breast cancer, genetic mutation