Tamoxifen alters the plasma concentration of molecules associated with cardiovascular risk in women with breast cancer undergoing chemotherapy

Abstract

Objectives: The objective of this study was to evaluate the effect of tamoxifen on blood markers that are associated with cardiovascular risk, such as C-reactive protein (CRP), apolipoprotein A-1 (Apo-A), and apolipoprotein B-100 (Apo-B), in women undergoing chemotherapy for breast cancer.

Methods: Over a period of 12 months, we followed 60 women with breast cancer. The women were divided into the following groups: a group that received only chemotherapy (n = 23), a group that received chemotherapy plus tamoxifen (n = 21), and a group that received only tamoxifen (n = 16). Plasma CRP levels were assessed at 0, 3, 6, and 12 months, and Apo-A and Apo B levels as well as the Apo-B/Apo-A ratio were assessed at 0 and 12 months.

Results: We found increases in the plasma concentration of CRP in the chemotherapy alone and chemotherapy plus tamoxifen groups after 3 and 6 months of treatment (before the introduction of tamoxifen). However, after 12 months of treatment, women who used tamoxifen (the chemotherapy plus tamoxifen and tamoxifen alone groups) showed a significant reduction in CRP and Apo-B levels and a decrease in the Apo-B/Apo-A ratio. A significant increase in serum Apo-A levels was observed in the group receiving chemotherapy alone as a treatment for breast cancer.

Conclusion: The use of tamoxifen after chemotherapy for the treatment of breast cancer significantly reduces the levels of cardiovascular disease risk markers (CRP, Apo-B, and the Apo-B/Apo-A ratio).

Figure 1.

Group division: women who received chemotherapy treatment for 6 months, women who received chemotherapy for 6 months followed by an additional 6 months of tamoxifen, and women who received tamoxifen for 12 months. Abbreviations: Apo-A, apolipoprotein A-1; APO-B, apolipoprotein B-100 ; CRP, C-reactive protein; T, time.

Figure 2.

Plasma concentrations of C-reactive protein (CRP) in the groups treated with chemotherapy alone (A), chemotherapy followed by tamoxifen (B), and tamoxifen alone (C). *p < .01 compared with the beginning (T0). #p < .01 compared with the third month (T3). +p < .01 compared with the sixth month (T6).

Figure 3.

Plasma concentrations of C-reactive protein (CRP) among the groups over time in the groups treated with chemotherapy alone (A), chemotherapy followed by tamoxifen (B), and tamoxifen alone (C). *p < .01 compared with the tamoxifen alone group. +p < .01 compared with the chemotherapy plus tamoxifen and tamoxifen alone groups.

Figure 4.

Plasma concentrations of Apo-A (A), Apo-B (B), and the Apo-B/Apo-A ratio (C) in the groups treated with chemotherapy alone, chemotherapy followed by tamoxifen, and tamoxifen alone. *p < .01 compared with the beginning (T0). Abbreviations: Apo-A, apolipoprotein A-1; Apo-B, apolipoprotein B-100; T, time.