Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer
Background: Stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for localized prostate cancer. The purpose of this study was to compare the prostate-specific antigen (PSA) kinetics between conventionally fractionated external beam radiotherapy (CF-EBRT) and SBRT boost after w...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2016-03-01
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| Series: | Prostate International |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2287888215300829 |
| _version_ | 1797725915098120192 |
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| author | Jeong Hoon Phak Hun Jung Kim Woo Chul Kim |
| author_facet | Jeong Hoon Phak Hun Jung Kim Woo Chul Kim |
| author_sort | Jeong Hoon Phak |
| collection | DOAJ |
| description | Background: Stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for localized prostate cancer. The purpose of this study was to compare the prostate-specific antigen (PSA) kinetics between conventionally fractionated external beam radiotherapy (CF-EBRT) and SBRT boost after whole pelvis EBRT (WP-EBRT) in localized prostate cancer.
Methods: A total of 77 patients with localized prostate cancer [T-stage, T1–T3; Gleason score (GS) 5–9; PSA < 20 ng/mL] were enrolled. A total of 35 patients were treated with SBRT boost (21 Gy in 3 fractions) after WP-EBRT and 42 patients were treated with CF-EBRT (45 Gy WP-EBRT and boost of 25.2–30.6 Gy in 1.8-Gy fractions). PSA nadir and rate of change in PSA (slope) were calculated and compared.
Results: With a median follow-up of 52.4 months (range, 14–74 months), the median PSA nadir and slope for SBRT boost were 0.29 ng/mL and −0.506, −0.235, −0.129, and −0.092 ng/mL/mo, respectively, for durations of 1 year, 2 years, 3 years, and 4 years postradiotherapy. Similarly, for CF-EBRT, the median PSA nadir and slopes were 0.39 ng/mL and −0.720 ng/mL/mo, −0.204 ng/mL/mo, −0.121 ng/mL/mo, and −0.067 ng/mL/mo, respectively. The slope of CF-EBRT was significantly different with a greater median rate of change for 1 year postradiotherapy than that of SBRT boost (P = 0.018). Contrastively, the slopes of SBRT boost for durations of 2 years, 3 years, and 4 years tended to be continuously greater than that of CF-EBRT. The significantly lower PSA nadir was observed in SBRT boost (median nadir 0.29 ng/mL) compared with CF-EBRT (median nadir 0.35 ng/mL, P = 0.025). Five-year biochemical failure (BCF) free survival was 94.3% for SBRT boost and 78.6% for CF-EBRT (P = 0.012).
Conclusion: Patients treated with SBRT boost after WP-EBRT experienced a lower PSA nadir and there tended to be a continuously greater rate of decline of PSA for durations of 2 years, 3 years, and 4 years than with CF-EBRT. The improved PSA kinetics of SBRT boost over CF-EBRT led to favorable BCF free survival. |
| first_indexed | 2024-03-12T10:38:10Z |
| format | Article |
| id | doaj.art-f524ad2f94af489b99fd5ed43440143f |
| institution | Directory Open Access Journal |
| issn | 2287-8882 |
| language | English |
| last_indexed | 2024-03-12T10:38:10Z |
| publishDate | 2016-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Prostate International |
| spelling | doaj.art-f524ad2f94af489b99fd5ed43440143f2023-09-02T08:33:39ZengElsevierProstate International2287-88822016-03-0141252910.1016/j.prnil.2015.12.001Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancerJeong Hoon PhakHun Jung KimWoo Chul KimBackground: Stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for localized prostate cancer. The purpose of this study was to compare the prostate-specific antigen (PSA) kinetics between conventionally fractionated external beam radiotherapy (CF-EBRT) and SBRT boost after whole pelvis EBRT (WP-EBRT) in localized prostate cancer. Methods: A total of 77 patients with localized prostate cancer [T-stage, T1–T3; Gleason score (GS) 5–9; PSA < 20 ng/mL] were enrolled. A total of 35 patients were treated with SBRT boost (21 Gy in 3 fractions) after WP-EBRT and 42 patients were treated with CF-EBRT (45 Gy WP-EBRT and boost of 25.2–30.6 Gy in 1.8-Gy fractions). PSA nadir and rate of change in PSA (slope) were calculated and compared. Results: With a median follow-up of 52.4 months (range, 14–74 months), the median PSA nadir and slope for SBRT boost were 0.29 ng/mL and −0.506, −0.235, −0.129, and −0.092 ng/mL/mo, respectively, for durations of 1 year, 2 years, 3 years, and 4 years postradiotherapy. Similarly, for CF-EBRT, the median PSA nadir and slopes were 0.39 ng/mL and −0.720 ng/mL/mo, −0.204 ng/mL/mo, −0.121 ng/mL/mo, and −0.067 ng/mL/mo, respectively. The slope of CF-EBRT was significantly different with a greater median rate of change for 1 year postradiotherapy than that of SBRT boost (P = 0.018). Contrastively, the slopes of SBRT boost for durations of 2 years, 3 years, and 4 years tended to be continuously greater than that of CF-EBRT. The significantly lower PSA nadir was observed in SBRT boost (median nadir 0.29 ng/mL) compared with CF-EBRT (median nadir 0.35 ng/mL, P = 0.025). Five-year biochemical failure (BCF) free survival was 94.3% for SBRT boost and 78.6% for CF-EBRT (P = 0.012). Conclusion: Patients treated with SBRT boost after WP-EBRT experienced a lower PSA nadir and there tended to be a continuously greater rate of decline of PSA for durations of 2 years, 3 years, and 4 years than with CF-EBRT. The improved PSA kinetics of SBRT boost over CF-EBRT led to favorable BCF free survival.http://www.sciencedirect.com/science/article/pii/S2287888215300829CyberknifeProstate cancerPSA kineticsPSA nadirStereotactic body radiotherapy |
| spellingShingle | Jeong Hoon Phak Hun Jung Kim Woo Chul Kim Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer Prostate International Cyberknife Prostate cancer PSA kinetics PSA nadir Stereotactic body radiotherapy |
| title | Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| title_full | Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| title_fullStr | Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| title_full_unstemmed | Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| title_short | Prostate-specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post-external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| title_sort | prostate specific antigen kinetics following hypofractionated stereotactic body radiotherapy boost as post external beam radiotherapy versus conventionally fractionated external beam radiotherapy for localized prostate cancer |
| topic | Cyberknife Prostate cancer PSA kinetics PSA nadir Stereotactic body radiotherapy |
| url | http://www.sciencedirect.com/science/article/pii/S2287888215300829 |
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