title: Biomonitoring of urinary tamoxifen and its metabolites from breast cancer patients using nonaqueous capillary electrophoresis with electrospray mass spectrometry.
abstract: Tamoxifen is an antiestrogen drug used to treat breast cancer. We have extracted tamoxifen and several of its metabolites from urine of patients with both metastatic (stage IV) and locally confined (stages I, II, and III) breast cancer. Analysis of these metabolites was performed by nonaqueous capillary electrophoresis with electrospray-mass spectrometry. Peak heights from extracted ion current electropherograms of the metabolites were used to establish a metabolic profile for each patient. We demonstrate substantial variation among patient profiles, statistically significant differences in the amount of urinary tamoxifen N-oxide found in stages I, II, and III compared to stage IV breast cancer patients, and statistically significant differences in the amount of 3,4-dihydroxytamoxifen found in progressors compared to nonprogressors with metastatic (stage IV) cancer.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, Canada.
authors.forename: S J
authors.initials: SJ
authors.lastname: Carter
authors.forename: X F
authors.initials: XF
authors.lastname: Li
authors.forename: J R
authors.initials: JR
authors.lastname: Mackey
authors.forename: S
authors.initials: S
authors.lastname: Modi
authors.forename: J
authors.initials: J
authors.lastname: Hanson
authors.forename: N J
authors.initials: NJ
authors.lastname: Dovichi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000378:metabolism / Q000627:therapeutic use / Q000652:urine*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000652:urine*; D002138:Calibration; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000378:metabolism / Q000652:urine*; D003404:Creatinine / Q000652:urine; D019075:Electrophoresis, Capillary / Q000379:methods*; D004965:Estrogen Antagonists / Q000378:metabolism / Q000627:therapeutic use / Q000652:urine*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015394:Molecular Structure; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013629:Tamoxifen / Q000378:metabolism / Q000627:therapeutic use / Q000652:urine*; D013997:Time Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D004965:Estrogen Antagonists; D013629:Tamoxifen; D003404:Creatinine