Comparative effects of anastrozole, tamoxifen alone and in combination on plasma lipids and bone-derived resorption during neoadjuvant therapy in the impact trial.
BACKGROUND
Estrogen has beneficial effects on lipid metabolism and bone preservation. The IMPACT trial evaluated neoadjuvant therapy with anastrozole or tamoxifen alone, or a combination. The comparative effects of these treatments on serum lipids and bone resorption were assessed.


METHODS
Non-fasting clotted blood samples were taken from 176 postmenopausal patients at baseline, 2 and 12 weeks for assessment of serum levels of estradiol, the bone resorption marker CTx and lipid profiles [total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and non-HDL cholesterol (N-HDL-C)].


RESULTS
After 12 weeks, tamoxifen was associated with a significant increase in HDL-C (26.5%), and a decrease in TC (6.5%) and N-HDL-C (12.3%). Anastrozole was associated with a significant increase in HDL-C (11.2%), and a non-significant increase in TC (2.9%) and N-HDL-C (3.4%), both of which were significantly different from tamoxifen. The combination was associated with a significant increase in HDL-C (9.4%), and a decrease in TC (10.9%) and N-HDL-C (13.9%). For tamoxifen and the combination, there were non-significant decreases in CTx compared with a significant increase (45.6%) with anastrozole. No correlation between serum estradiol and CTx was seen in any of the treatment groups.


CONCLUSIONS
Anastrozole did not have a detrimental effect on lipid profiles following 3 months of therapy. There was a significant increase in CTx with anastrozole in contrast to tamoxifen.
Banerjee
S
S
Breast Unit, Royal Marsden Hospital, London & Sutton, London, UK.
Smith
I E
IE
Folkerd
L
L
Iqbal
J
J
Barker
P
P
Dowsett
M
M
D000368:Aged; D000077384:Anastrozole; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D001862:Bone Resorption / Q000188:drug therapy; D001943:Breast Neoplasms / Q000150:complications / Q000188:drug therapy*; D004311:Double-Blind Method; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009570:Nitriles / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D017698:Postmenopause; D013629:Tamoxifen / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*
D018931:Antineoplastic Agents, Hormonal; D015415:Biomarkers; D008055:Lipids; D009570:Nitriles; D014230:Triazoles; D013629:Tamoxifen; D000077384:Anastrozole; D004958:Estradiol