TY - JOUR
T1 - After low and high dose-rate interstitial brachytherapy followed by IMRT radiotherapy for intermediate and high risk prostate cancer
AU - Nakamura, Satoshi
AU - Murakami, Naoya
AU - Inaba, Koji
AU - Wakita, Akihisa
AU - Kobayashi, Kazuma
AU - Takahashi, Kana
AU - Okamoto, Hiroyuki
AU - Umezawa, Rei
AU - Morota, Madoka
AU - Sumi, Minako
AU - Igaki, Hiroshi
AU - Ito, Yoshinori
AU - Itami, Jun
N1 - Funding Information:
This work was supported by a study group of MicroSelectron HDR, Japan, and was partially supported by a JSPS Grant-in-Aid for young Scientists (B) Grant Number 26860410, by the Practical Research for Innovative Cancer Control and by the Medical Research and Development Programs Focused on Technology Transfer: Development of Advanced Measurement and Analysis Systems (SENTAN) from the Japan Agency for Medical Research and Development, AMED, and by the National Cancer Center Research and Development Fund (26-A-28).
Publisher Copyright:
© 2016 Nakamura et al.
PY - 2016/5/3
Y1 - 2016/5/3
N2 - Background: The study aimed to compare urinary symptoms in patients with clinically localized prostate cancer after a combination of either low-dose-rate or high-dose-rate interstitial brachytherapy along with intensity-modulated radiation therapy (LDR-ISBT + IMRT or HDR-ISBT + IMRT). Methods: From June 2009 to April 2014, 16 and 22 patients were treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT, respectively. No patient from these groups was excluded from this study. The prescribed dose of LDR-ISBT, HDR-ISBT, and IMRT was 115 Gy, 20 Gy in 2 fractions, and 46 Gy in 23 fractions, respectively. Obstructive and irritative urinary symptoms were assessed by the International Prostate Symptom Score (IPSS) examined before and after treatments. After ISBT, IPSS was evaluated in the 1st and 4th weeks, then every 2-3 months for the 1st year, and every 6 months thereafter. Results: The median follow-up of the patients treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT was 1070.5 days and 1048.5 days, respectively (p = 0.321). The IPSS-increment in the LDR-ISBT + IMRT group was greater than that in the HDR-ISBT + IMRT between 91 and 180 days after ISBT (p = 0.015). In the LDR-ISBT + IMRT group, the IPSS took longer time to return to the initial level than in the HDR-ISBT + IMRT group (in LDR-ISBT + IMRT group, the recovery time was 90 days later). The dose to urethra showed a statistically significant association with the IPSS-increment in the irritative urinary symptoms (p = 0.011). Clinical outcomes were comparable between both the groups. Conclusions: Both therapeutic modalities are safe and well suited for patients with clinically localized prostate cancer; however, it took patients longer to recover from LDR-ISBT + IMRT than from HDR-ISBT + IMRT. It is possible that fast dose delivery induced early symptoms and early recovery, while gradual dose delivery induced late symptoms and late recovery. Urethral dose reductions were associated with small increments in IPSS.
AB - Background: The study aimed to compare urinary symptoms in patients with clinically localized prostate cancer after a combination of either low-dose-rate or high-dose-rate interstitial brachytherapy along with intensity-modulated radiation therapy (LDR-ISBT + IMRT or HDR-ISBT + IMRT). Methods: From June 2009 to April 2014, 16 and 22 patients were treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT, respectively. No patient from these groups was excluded from this study. The prescribed dose of LDR-ISBT, HDR-ISBT, and IMRT was 115 Gy, 20 Gy in 2 fractions, and 46 Gy in 23 fractions, respectively. Obstructive and irritative urinary symptoms were assessed by the International Prostate Symptom Score (IPSS) examined before and after treatments. After ISBT, IPSS was evaluated in the 1st and 4th weeks, then every 2-3 months for the 1st year, and every 6 months thereafter. Results: The median follow-up of the patients treated with LDR-ISBT + IMRT and HDR-ISBT + IMRT was 1070.5 days and 1048.5 days, respectively (p = 0.321). The IPSS-increment in the LDR-ISBT + IMRT group was greater than that in the HDR-ISBT + IMRT between 91 and 180 days after ISBT (p = 0.015). In the LDR-ISBT + IMRT group, the IPSS took longer time to return to the initial level than in the HDR-ISBT + IMRT group (in LDR-ISBT + IMRT group, the recovery time was 90 days later). The dose to urethra showed a statistically significant association with the IPSS-increment in the irritative urinary symptoms (p = 0.011). Clinical outcomes were comparable between both the groups. Conclusions: Both therapeutic modalities are safe and well suited for patients with clinically localized prostate cancer; however, it took patients longer to recover from LDR-ISBT + IMRT than from HDR-ISBT + IMRT. It is possible that fast dose delivery induced early symptoms and early recovery, while gradual dose delivery induced late symptoms and late recovery. Urethral dose reductions were associated with small increments in IPSS.
KW - Clinically localized prostate cancer
KW - High-dose-rate brachytherapy
KW - Intensity-modulated radiation therapy (IMRT)
KW - International Prostate Symptom Score (IPSS)
KW - Low-dose-rate brachytherapy
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U2 - 10.1186/s12885-016-2329-7
DO - 10.1186/s12885-016-2329-7
M3 - Article
C2 - 27142069
AN - SCOPUS:84977644480
VL - 16
JO - BMC Cancer
JF - BMC Cancer
SN - 1471-2407
IS - 1
M1 - 296
ER -
