Ra-223 and Ethinylestradiol Combination Therapy in Castration-resistant Prostate Cancer

Anticancer Res. 2022 Feb;42(2):1065-1071. doi: 10.21873/anticanres.15568.

Abstract

Background/aim: Ra-223 is a therapeutic agent for bone metastatic castration-resistant prostate cancer (mCRPC). We examined the efficacy of a treatment method using Ra-223 together with ethinylestradiol (EE).

Patients and methods: Patients who received Ra-223 three or more times were included and two groups (with or without EE) were compared retrospectively.

Results: Eighteen patients were treated with Ra-223 and EE concomitantly (EstRadium therapy) and 13 patients were treated with Ra-223 alone or Ra-223 and agents other than EE (non-EstRadium therapy). The number of patients with decreased serum prostate-specific antigen level was significantly higher in the EstRadium therapy group than in the non-EstRadium therapy group (p=0.029).

Conclusion: The combination of Ra-223 and EE, compared to Ra-223 alone, is an effective treatment option for bone mCRPC patients, in terms of PSA response.

Keywords: Ethinylestradiol; Ra-223; castration resistant prostate cancer; prostate-specific antigen.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Bone Neoplasms / blood
  • Bone Neoplasms / mortality
  • Bone Neoplasms / secondary
  • Bone Neoplasms / therapy*
  • Case-Control Studies
  • Chemoradiotherapy / methods*
  • Ethinyl Estradiol / administration & dosage*
  • Humans
  • Japan / epidemiology
  • Kallikreins / blood
  • Male
  • Middle Aged
  • Prostate-Specific Antigen / blood
  • Prostatic Neoplasms, Castration-Resistant / blood
  • Prostatic Neoplasms, Castration-Resistant / mortality
  • Prostatic Neoplasms, Castration-Resistant / pathology
  • Prostatic Neoplasms, Castration-Resistant / therapy*
  • Radium / administration & dosage*
  • Retrospective Studies
  • Survival Analysis
  • Treatment Outcome

Substances

  • Ethinyl Estradiol
  • Radium-223
  • KLK3 protein, human
  • Kallikreins
  • Prostate-Specific Antigen
  • Radium