MOLECULAR GENETIC STUDY ARIADNA HELPED DETECT A NEW MUTATION IN BREAST CANCER

A year ago, a young patient of 39 years old came to the A.Tsyb Medical Radiological Research Centre, – branch of the Federal State Budgetary Institution of the “National Medical Research Radiological Centre” of the Ministry of Health of the Russian Federation and complained about formation of a left breast. Doctors diagnosed her with breast cancer of unspecific type II degree of malignancy and metastasis of iron cancer in the axillary lymph node. However, there were no mutations in BRCA 1/2 genes. Taking into account the stage of the disease and the identified type of tumor, at the first stage of treatment the patient underwent subcutaneous mastectomy (removal) of the mammary gland with simultaneous reconstruction with an endoprosthesis.

Postoperative histological studies confirmed the A-luminal surrogate subtype and helped to detect metastases in three axillary lymph nodes. The patient was given adjuvant hormone therapy. However, 11 months later, during the dynamic monitoring, new metastases were detected, now in the lumbar and iliac bones. The patient was prescribed for hormone therapy on the next line. The PET-CT re-analysis after six months of use found an increase in metabolic activity in previous sites and new ones in the thoracic and posterior joints. All known treatments, as described in the clinical recommendations, seemed to have been exhausted. It made doctors look for a special, personalized approach to treatment.

And oncologists decided to use the most modern method of analysis of tumor cells, which was developed by scientists from the National Medical Research Radiological Centre of the Ministry of Health of the Russian Federation. Using the complex molecular genetic study ARIADNA, which allows us to determine the DNA and RNA sequence in more than 22 thousand blood and tumor samples, a previously undescribed mutation in the PALB2, PIK3CA gene was identified in our patient, which made it possible to accurately adjust medication therapy. The plan has worked.

“This case allows us to make a very important conclusion: the luminal A subtype of breast cancer is not homogeneous in biological properties, there are rare clinical cases of an aggressive course of the disease,” emphasizes the head of the department of new medical technologies of the A. Tsyb MRRC, professor, doctor of medical sciences M.V. Kiseleva. Continued development of a genetic panel for hormone-dependent breast cancer will make it possible to predict the risk of recurrence and isolating patients with high progression to achieve stable results in their treatment.”