Catecholestrogens excretion in smoking and non-smoking postmenopausal women receiving estrogen replacement therapy

Estrogens are involved in the etiology of breast cancer. Their blastomogeni c influence may be partly realized through their conversion into catecholes trogens, rate of which may be modified by smoking. The risk of having breas t cancer diagnosed can increase in women using estrogen replacement therapy (ERT). The principal aim of this investigation was to compare the excretio n of classical estrogens and catecholestrogens in smoking and non-smoking p ostmenopausal women receiving Progynova (estradiol valerate, 2 mg/day, 1 mo nth). Total 16 women were studied before and after treatment. Urinary estro gen profile method based on isotope dilution capillary gas chromatography-m ass spectrometry was used. Before ERT, significantly lower excretion of 16- epiestriol and 4-hydroxyestrone (4-OHE1) and lower ratio of 4-OHE1/E1 were revealed in smokers. After ERT, much higher excretion of 2-OHE1, and 4-hydr oxyestradiol (4-OHE2), higher ratios of 2-OHE1/E1 and 4-OHE1/E1 and lower r atio of 2-methoxyestrone/2-OHE1 were discovered in smokers as compared to n on-smoking women. In conclusion only combination of ERT + smoking and not s moking itself leads to the specific prevalence of catecholestrogens (2-OH- and carcinogenic and DNA-damaging 4-OH-metabolites) that may increase risk of genotoxic variant of hormone-induced breast carcinogenesis without influ ence on the total morbidity. (C) 2000 Elsevier Science Ltd. All rights rese rved.