Will our clinical practice change with the availability of new diagnostic methods, drug therapy and assessment of its effectiveness? Clinical case: hormone receptor-positive, HER2-negative metastatic breast cancer

Background. The therapeutic capabilities for the treatment of hormone receptor-positive (HR+), HER2-negative (HER2-) metastatic breast cancer (mBC) have significantly increased after the introduction of new drugs for hormone therapy and their combinations with targeted drugs into clinical practice. The article discusses some key issues related to the use of new diagnostic methods, treatment and their potential impact on the choice of drug therapy regimen for hormone receptor-positive (HR+), HER2-negative (HER2-) metastatic breast cancer (mBC). Description of the clinical case. The article analyzes the clinical case of a patient with luminal type of breast cancer who had not previously received adjuvant hormone therapy. 4 years after the completion of the combination therapy of the primary tumor, multiple bone metastases without metastatic lesions of other systems and organs were detected. In accordance with the treatment plan, the patient received fulvestrant in first-line therapy for 8 years; it was discontinued due to the progression of the disease, and the second-line therapy with palbociclib + letrozole was recommended. The results of the genetic study were obtained one month before the patient’s death. Conclusion. With the timely obtainment of data on the biological subtype of the tumor, genetic testing, it is likely that other drug regimens with higher expected efficacy would have been prescribed. Today, molecular genetic testing of a patient’s tumor sample is becoming increasingly available. However, for a timely and urgent testing, it is necessary to improve the logistics and routing of the delivery of biosamples of patients, and the preparation of accompanying documentation.

metastatic breast cancer, molecular genetic testing, hormone therapy, chemotherapy