The complex evaluation of tumor oxygen state and vasculature during preoperative chemotherapy in patients with breast cancer

Effective breast cancer treatment requires the assessment of metabolic changes of tumor tissue during chemo- and hormonotherapy for prediction tumor response. Evaluation of the dynamics of tumor oxygen state (by diffuse optical spectroscopy imaging) and tumor vasculature (by ultrasound investigation in power Doppler mode) was performed before treatment beginning and before the second cycle of chemotherapy in 16 patients who received preoperative chemotherapy. Changes of these indicators were compared then with tumor pathologic response. Breast tumors demonstrated different dynamics of tumor oxygenation depending on the changes of tumor tissue. The increase of the tumor oxygenation after the first cycle of chemotherapy was observed in five of six patients with grade 4 and 5 of pathologic tumor response. Decrease of the oxygenation level was revealed in one patient with the 4 th degree of tumor response. Variable changes of the oxygenation level were mentioned in the patients with moderate (the 3 d degree) tumor response. Tumor oxygenation decreased or was unchanged in case of 1 or 2 degree of tumor response in five of six cases. The study of the tumor blood vessels didn't reveal any correlation between vasculature changes and tumor response under the performed treatment. The trend of tumor oxygenation in early time after treatment beginning might be a predictive criterion of tumor sensitivity to chemotherapy.