title: Use of hormone replacement therapy before and after ovarian cancer diagnosis and ovarian cancer survival.
abstract: Use of hormone replacement therapy (HRT) has been hypothesized to affect survival of epithelial ovarian cancer (EOC). We studied 5-year survival in patients with invasive EOC and borderline ovarian tumors (BOT) according to HRT use before and after diagnosis in a prospective nation-wide cohort study of 799 women diagnosed with EOC (n = 649) and BOT (n = 150) aged 50-74 years in 1993-1995 in Sweden. Cox regression was used to obtain multivariate age-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Multivariate models included indicator variables for age, tumor stage, grade and histological subtype. After 5 years of follow-up, 45% of the patients with EOC and 93% of the patients with BOT were alive. For women with BOT there were no associations between HRT-use pre- or postdiagnosis and survival. There was no overall difference in 5-year EOC survival according to use HRT before diagnosis (multivariate HR = 0.83, 95% CI = 0.65-1.08), except for serous EOC (HR = 0.69, 95% CI = 0.48-0.98). Analyses of different HRT preparations, duration and recency of use did not reveal any variations in pattern of survival. We observed a better survival for EOC-patients who used HRT after diagnosis (multivariate HR = 0.57, 95% CI = 0.42-0.78). We conclude that HRT-use prior to diagnosis of EOC does not affect 5-year survival, except for a possible survival advantage in serous EOC. Women using HRT after diagnosis had a better survival than women with no use, but we cannot rule out that this latter finding may reflect a subtle selection process.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden.
authors.forename: Chantal
authors.initials: C
authors.lastname: Mascarenhas
authors.forename: Mats
authors.initials: M
authors.lastname: Lambe
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Kjell
authors.initials: K
authors.lastname: Bergfeldt
authors.forename: Tomas
authors.initials: T
authors.lastname: Riman
authors.forename: Ingemar
authors.initials: I
authors.lastname: Persson
authors.forename: Elisabete
authors.initials: E
authors.lastname: Weiderpass
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D020249:Hormone Replacement Therapy / Q000706:statistics & numerical data*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D016016:Proportional Hazards Models; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors