THE USE OF PET/CT TO EVALUATE THE EFFECTIVENESS OF DRUG THERAPY FOR DISSEMINATED THE TUMOR BREAST CANCER

Abstract

The current literature and the National Comprehensive Cancer Network (NCCN) guidelines state that ¹⁸F-FDG PET/CT is not routine for early diagnosis of breast cancer, and rather PET/CT scanning should be performed for patients with stage III disease or when conventional staging studies yield non-diagnostic or suspicious results because this modality has been shown to upstage patients compared to conventional imaging and thus has an impact on disease management and prognosis. Although 18F-FDG PET/CT mammography was able to detect axillary lymph node metastases with a high sensitivity, this method cannot soon be expected to replace the combination of clinical examination, ultrasound, and sentinel lymph node biopsy for axillary assessment. Drug therapy remains the main method of complex treatment at these stages. Positron emission tomography (PET) with fluorodeoxyglucose has now been used to assess the effect of the treatment. This method makes it possible to assess changes in the tumor at the cellular level long before morphological manifestations. Thus, a decrease in the accumulation of fluorodeoxyglucose in the tumor by more than 45% of the initial one predicts a complete pathomorphological response to drug therapy with great accuracy.