BRCA1/ BRCA2 Pathogenic Variant Breast Cancer: Treatment and Prevention Strategies

Breast cancer has likely affected us all. This publication reviews treatment and prevention studies to date for BRCA1/BRCA2 breast cancers, including the use of Poly adenosine diphosphate [ADP]-ribose polymerase (PARP) inhibitors. One study describing the PARP inhibitors, olaparib and talazoparib, showed improvement of median progression-free survival around three months.

Poly adenosine diphosphate [ADP]-ribose polymerase (PARP) is essential to mend DNA single-strand breaks through base excision repair. PARP inhibitors hinder base excision repair and when there are defects in the homologuous recombination pathway due to mutations in the BRCA genes and proteins, the use of PARP inhibitors induces synthetic lethality. Five PARP inhibitors are currently available including olaparib, talazoparib, rucaparib, niraparib, and veliparib. Olaparib, rucaparib, and niraparib are approved treatments for ovarian cancer and olaparib is approved for the treatment of HER2− metastatic germline BRCA pathogenic variant breast cancer by the United States Food and Drug Administration (FDA).

A link to the full publication is available below.

Figure 1: Incidence of breast cancer. (A) hereditary breast cancer accounts for 5–10% of all breast cancer cases. (B) BRCA1/BRCA2 pathogenic variant breast cancer accounts for up to 60% of all hereditary breast cancer cases [97]. Copyright permission for this figure was obtained from publisher.

AUTHORS:

Anbok Lee, M.D., Ph.D., 1 Byung-In Moon, M.D., Ph.D., 2 and Tae Hyun Kim, M.D., Ph.D. 1

AUTHOR AFFILIATIONS:

1 Department of Surgery, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea.

2 Department of Surgery, Mokdong Hospital, Ewha Womans University College of Medicine, Seoul, Korea.

Corresponding author:
Dr. Anbok Lee, M.D., Ph.D. Department of Surgery, Busan Paik Hospital, Inje University, College of Medicine, 75 Bokji-ro, Busanjin-gu, Busan 47392, Korea.
Tel: +82-51-890-6859, Fax: +82-51-898-9427, E-mail: ten.liamnah@eel-ba

ABSTRACT:

Hereditary breast cancer is known for its strong tendency of inheritance. Most hereditary breast cancers are related to BRCA1/BRCA2 pathogenic variants. The lifelong risk of breast cancer in pathogenic BRCA1 and BRCA2 variant carriers is approximately 65% and 45%, respectively, whereas that of ovarian cancer is estimated to be 39% and 11%, respectively. Therefore, understanding these variants and clinical knowledge on their occurrence in breast cancers and carriers are important. BRCA1 pathogenic variant breast cancer shows more aggressive clinicopathological features than the BRCA2 pathogenic variant breast cancer. Compared with sporadic breast cancer, their prognosis is still debated. Treatments of BRCA1/BRCA2 pathogenic variant breast cancer are similar to those for BRCA-negative breast cancer, mainly including surgery, radiotherapy, and chemotherapy. Recently, various clinical trials have investigated poly (adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitor treatment for advanced-stage BRCA1/BRCA2 pathogenic variant breast cancer. Among the various PARP inhibitors, olaparib and talazoparib, which reached phase III clinical trials, showed improvement of median progression-free survival around three months. Preventive and surveillance strategies for BRCA pathogenic variant breast cancer to reduce cancer recurrence and improve treatment outcomes have recently received increasing attention. In this review, we provide an information on the clinical features of BRCA1/BRCA2 pathogenic variant breast cancer and clinical recommendations for BRCA pathogenic variant carriers, with a focus on treatment and prevention strategies. With this knowledge, clinicians could manage the BRCA1/BRCA2 pathogenic variant breast cancer patients more effectively.

DOI:

https://synapse.koreamed.org/DOIx.php?id=10.3343/alm.2020.40.2.114