Onkológia 2/2020

The efect of CDK 4/6 inhibition on overal survival in metastatic breast cancer

Hormone-receptor positive breast carcinoma represents the most common type of breast cancer, accounting for approximately 75% of all breast tumors. Endocrine therapy has been the most important treatment strategy of patients with hormone-receptor positive and HER2 negative disease. Several new drugs have been implemented into clinical practice over past 4 years including three cyclin-dependent kinase inhibitors (CDK). Cyclin-dependent kinases 4 and 6 play an important role in the process of cell cycle regulation. Clinical studies evaluating the efficacy of CDK 4/6 inhibitors (palbociclib, ribociclib, abemaciclib) in the treatment of HR+, HER2- advanced breast cancer demonstrated a statistically significant benefit in prolonged progression free survival (PFS). Besides PFS, ribociclib and abemaciclib also demonstrated statistically significant prolonged overall survival (OS), including achieving a significant overall treatment response (ORR) in patients with measurable disease. This treatment managed to maintain and even to improve the quality of life of palliative patients. Quality of life is the most valued indicator of clinical benefit. International treatment guidelines for the treatment of advanced breast cancer (ESMO, NCCN) strongly recommend a combination of aromatase inhibitor and CDK 4/6 inhibitor for the 1st treatment line of advanced disease, as well as a combination of CDK 4/6 inhibitor and fulvestrant in the 1st and 2nd treatment line. Therefore, it is essential that this effective and safe innovative treatment becomes a commonly available treatment standard for patients with advanced breast cancer in our country.

Keywords: breast cancer, premenopausal/peri/postmenopausal women, CDK 4/6 inhibitors, endocrine therapy, hormone receptor-positive breast carcinoma