title: Feature of amenorrhea in postoperative tamoxifen users with breast cancer.
abstract: OBJECTIVE
  Tamoxifen has been used to prevent the recurrence of breast cancer. However, tamoxifen-users frequently experience amenorrhea and it can be confused from that caused by other hormonal abnormalities. In amenorrheic patients without breast cancer, clinicians usually measure the sex hormone levels that are known to be associated with ovarian or menstrual function. This study aimed to investigate the feature of female sex hormones in premenopausal breast cancer patients undergoing tamoxifen treatment.
  
  
  METHODS
  The medical records of fifty-nine premenopausal breast cancer patients who underwent tamoxifen treatment were reviewed retrospectively. The study population consisted of amenorrheic patients (n=36) and patients with menstruation (n=23). Serum hormone levels were measured either specifically between cycle days 2 and 5 in menstruating patients or at any time in amenorrheic participants.
  
  
  RESULTS
  Serum levels of lutenizing hormone and estradiol were not statistically different according to the presence of menstruation. Serum follicle stimulating hormone level was significantly higher in amenorrheic patients (8.1±5.7 mIU/mL) than those in menstruating subjects (5.1±2.2 mIU/mL) (p=0.01). Serum concentration of thyroid stimulating hormone was lower in patients with amenorrhea (1.5±0.9 vs. 2.3±2.2 μIU/mL, p=0.04), although the prevalence of hypo- or hyperthyroidism was not different according to the pattern of menstruation.
  
  
  CONCLUSIONS
  Menstruation status and hormone levels can be influenced by tamoxifen use in reproductive age breast cancer patients. Physicians should be attentive to the alteration of pituitary hormone levels in addition to sex steroid hormones in this population.
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Hoon
authors.identifier: http://orcid.org/0000-0002-5623-6368
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Surgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Wonshik
authors.identifier: http://orcid.org/0000-0001-7310-0764
authors.initials: W
authors.lastname: Han
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea. jyhsyk@snu.ac.kr.
authors.forename: Seung Yup
authors.identifier: http://orcid.org/0000-0002-6423-854X
authors.initials: SY
authors.lastname: Ku
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Chang Suk
authors.identifier: http://orcid.org/0000-0003-1835-7350
authors.initials: CS
authors.lastname: Suh
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Seok Hyun
authors.identifier: http://orcid.org/0000-0003-0649-3224
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Young Min
authors.initials: YM
authors.lastname: Choi
mesh_terms: D000328:Adult; D000568:Amenorrhea / Q000097:blood / Q000139:chemically induced*; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects*; D001943:Breast Neoplasms / Q000188:drug therapy*; D016022:Case-Control Studies; D017024:Chemotherapy, Adjuvant; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D017697:Premenopause / Q000097:blood; D012189:Retrospective Studies; D013629:Tamoxifen / Q000009:adverse effects*; D013972:Thyrotropin / Q000097:blood
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin
keywords: Amenorrhea; Breast Neoplasms; Tamoxifen