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Published on: March 6, 2018
Brachytherapy for prostate cancer in Japan
1Department of Urology, National Tokyo Medical Center and Department of Urology, School of Medicine, Keio University, Tokyo, Japan. saitoshr@netjoy.ne.jp
Summary
Low-dose rate brachytherapy using iridium-192 (Ir-192) offers a safe and effective treatment for localized prostate cancer. This minimally invasive procedure shows significant tumor regression and minimal impact on erectile function in patients with lower prostate-specific antigen (PSA) levels.
Area of Science:
- Oncology
- Radiation Oncology
- Urology
Background:
- Prostate cancer treatment options are evolving.
- Brachytherapy offers a minimally invasive approach.
- Iridium-192 (Ir-192) is an available isotope for brachytherapy in Japan.
Purpose of the Study:
- To evaluate the efficacy and safety of low-dose rate brachytherapy using Ir-192 for localized prostate cancer.
- To assess treatment outcomes based on prostate-specific antigen (PSA) levels and tumor response.
- To determine the impact on erectile function and overall complications.
Main Methods:
- Twenty-six localized prostate cancer patients received Ir-192 brachytherapy.
- Transperineal needle insertion with Ir-192 wire placement.
- Dose distribution calculated via CT imaging for >70 Gy irradiation.
- Follow-up included PSA monitoring, MRI, biopsy, and erectile function assessment.
Main Results:
- All patients with initial PSA < 25 ng/ml showed continuous PSA decrease without biochemical failure.
- MRI confirmed tumor regression within 6 months post-treatment.
- Biopsies showed fibrosis in favorable cases and viable tumor cells in cases of PSA failure.
- Minimal impact on erectile function was observed (nocturnal penile tumescence and IIEF 15 score).
- No major side effects or complications were reported.
Conclusions:
- Ir-192 brachytherapy is a safe and effective treatment for localized prostate cancer.
- The procedure demonstrates good tumor control, particularly in patients with lower PSA levels.
- It is a less invasive option with minimal adverse effects on sexual function.
