Long-term survival of non-localized epithelial ovarian cancer among women using menopausal hormone therapy prior to diagnosis - the Extreme study
Menée au Danemark à partir de données 2000-2014 portant sur 3 776 patientes atteintes d'un cancer épithélial de l'ovaire non localisé, cette étude analyse l'impact, sur la survie à long terme, d'un traitement hormonal substitutif de la ménopause antérieur au diagnostic de cancer
Prediagnostic use of menopausal hormone therapy (MHT) has been suggested to be associated with improved survival of epithelial ovarian cancer (EOC). We investigated the potential long-term survival benefit of prediagnostic MHT use in women ≥50 years with non-localized EOC using the Extreme study including all women in Denmark registered with non-localized EOC during 2000–2014 (N=3,776). We obtained individual-level information on prediagnostic use of systemic estrogen therapy (ET) and estrogen plus progestin therapy (EPT) from the National Prescription Registry and estimated absolute and relative five- and ten-year survival probabilities with 95% confidence intervals (CIs) using pseudo-values, taking into account histology, comorbidity, income, and residual disease. Among women not having used prediagnostic MHT, five- and ten-year absolute survival probabilities were 19% and 11%, respectively. Compared with MHT non-users, prediagnostic systemic ET use for 3–4 years and ≥5 years was associated with 1.43 (95% CI: 1.01–2.02) and 1.22 (95% CI: 0.96–1.55) times higher five-year survival probabilities, respectively. Ten-year survival probabilities were also increased but not statistically significantly. Among prediagnostic EPT users, increased five-year (1.14, 95% CI: 0.85–1.53) and ten-year (1.38, 95% CI: 0.91–2.08) survival probabilities were observed after use for 3–4 years compared with MHT non-use, whereas EPT use for ≥5 years was not associated with long-term survival of non-localized EOC. Our findings may suggest a better long-term survival of non-localized EOC in women having used long-term prediagnostic ET. However, the statistical precision of our results did not allow firm conclusions and more studies are needed. This article is protected by copyright. All rights reserved.