[Chromosomal restructurings and the distribution of chromosome fragile sites in the peripheral blood lymphocytes in a breast cancer patient after cytostatic therapy].

Cytogenetic analysis was performed repeatedly on a breast cancer patient since the beginning of the antitumor treatment. Double minute chromosomes (DMS, 2-10 per cell) were found in less than 2% of peripheral blood lymphocytes besides other chromosomal abnormalities after radiation therapy and 8 months after chemotherapy. The level of structural chromosomal aberrations two years after the therapeutic treatment was 0.13-0.14 aberrations per cell, but DMS were not observed. Estimation of the fragile site (FS) frequency and distribution at this time revealed a significant expression of the common FS FRAGF (9q1.2) after the treatment of blood culture with 5-bromo-2-deoxyuridine at dose levels of 7 and 50 g/l and enhanced fragility in chromosome band 1p35-36.1 (FRA1A) in folate-deprived conditions. Rare FS were not found. The presented data are discussed.