The state of gene TOP2A and chromosome 17 in tumor cells as predictors of response to anthracycline treatment in breast cancer
Objective. To study the significance of the state of the gene TOP2A and chromosome 17 as prognostic factors of the sensitivity of breast cancer to anthracyclines. Material and methods. The study enrolled 167 patients with operable breast cancer included in the retrospective group (n = 98) (2004 - 2010) and prospective one (n = 69) (2011 - 2014). In all cases was performed adjuvant anthracycline-containing chemotherapy The criteria for curative effect assessment was cancer-specific survival. The state of gene TOP2A and the chromosome 17 in the tumor was determined by fluorescence in situ hybridization (FISH). Results. Retrospective part: 5-year cancer-specific survival in the control group was 55.7 ± 6.4%, in the main - 40.5 ± 8.1% (log-rank test p = 0.374). The survival with polysomy of chromosome 17 was 55.6 ± 11.4% and for amplification of the TOP2A gene was 31.5 ± 13.9%. In the group with co-amplification of genes Her2/neu + TOP2A it was 44.1 ± 13.5%, in the group with its absence - 46.7 ± 14.9% (log-rank test p = 0.530). Prospective part: 5-year cancer-specific survival in the control group was 68.6 ± 6.7%, in the main group - 63.2 ± 11.9 (log-rank test p = 0.81). The 5-year cancer-specific survival in the group with genes co-amplification was 56.2 ± 15.3% and in the group with its absence 47.5 ± 15.3% (log-rank test p = 0.63). Conclusions. The polysomy of chromosome 17 is associated with high efficacy of adjuvant anthracycline-containing chemotherapy. Amplification of the TOP2A gene, monosomy of chromosome 17 and deletion of the gene with a lower one.