High-dose-rate brachytherapy combined with external beam radiotherapy for localized prostate cancer: Correlation between clinical and dosimetric parameters and the incidence of rectal bleeding.

2013 ◽  
Vol 31 (6_suppl) ◽  
pp. 213-213
Author(s):  
Shinji Kariya ◽  
Ichiro Yamasaki ◽  
Shingo Ashida ◽  
Kenji Tamura ◽  
Taro Shuin ◽  
...  

213 Background: Several investigators have advocated that the alpha/beta ratio for prostate cancer is atypically low, and that hypofractionated radiotherapy or high-dose-rate brachytherapy (HDR-BT) regimens using appropriate radiation doses are expected to improve the local control rate for localized prostate cancer. However, the increase in the total biological effective dose (BED) may cause increased severity and incidence of normal tissue complications. The purpose of this study was to investigate what clinical and dosimetric factors affected the incidence of rectal bleeding after HDR-BT combined with external beam radiotherapy (EBRT). Methods: A total of 143 patients with localized prostate cancer underwent HDR-BT combined with EBRT. The fractionation schema for HDR-BT and EBRT was prospectively changed: 9 Gy x 2 + 2 Gy x 20 (BED1.5 = 219 Gy, BED3 = 139 Gy) in 57 patients (Group 1); and 9 Gy x 2 + 3 Gy x 13 (BED1.5 = 243 Gy, BED3= 150 Gy) in 86 patients (Group 2). Median follow-up was 59 (range, 36 – 94) months. The toxicities were graded based on the National Cancer Institute-Common Terminology Criteria for Adverse Events v3.0. Results: Sixteen (11.2 %) and one patients developed Grade 2 and 3 rectal bleedings, respectively. There were no significant differences between Group 1 and Group 2 in the incidence of Grade 2 and 3 rectal bleedings (12.3% and 11.6%, respectively). Grade 2 and 3 rectal bleedings occurred much more in the patients receiving the antiplatelet therapy (AT) (19.4%) than those without a history of AT (9.8%) and in the patients with diabetes mellitus (DM) (37.5%) than those without DM (10.4%). However, neither AT nor DM were risk factors in univariate analysis. Regarding dosimetric factors, V75 > 2cc, V90 > 0.2cc, D2 > 7 Gy, and D1 > 7.4 Gy were statistically-significant risk factors. In multivariate analysis, DM was the only statistically-significant risk factor. Conclusions: BED escalation could be performed without severe rectal bleeding in HDR-BT combined with EBRT. V75 > 2cc, V90 > 0.2cc, D2 > 7 Gy, D1 > 7.4 Gy, and DM were risk factors for the incidence of rectal bleeding in HDR-BT combined with EBRT. Clinical trial information: 18-9.

2019 ◽  
Vol 37 (7_suppl) ◽  
pp. 5-5
Author(s):  
Jacob Samuel Parzen ◽  
Hong Ye ◽  
Gary S. Gustafson ◽  
Alvaro Martinez ◽  
Evelyn Sebastian ◽  
...  

5 Background: We present a large retrospective analysis comparing rectal toxicity following high dose rate (HDR) brachytherapy as monotherapy relative to dose-escalated external beam radiotherapy (EBRT) for patients with localized prostate cancer. Methods: 2683 patients treated with HDR or EBRT between 1994 and 2017 were included. 545 (20.3%) received HDR and 2138 (79.7%) EBRT. HDR fractionation was 38 Gy/4 fractions (n=321), 24 Gy/2 (n=96), or 27 Gy/2 (n=128). EBRT patients received a median dose of 75.6 Gy in 1.8 Gy fractions [range 70.2-82.8 Gy], using either 3D conformal or intensity modulated radiotherapy (IMRT). All EBRT patients underwent 3D image guidance via an off-line adaptive process. Treatment was directed to prostate only (n=780) or prostate and seminal vesicles (n=1351). No nodal therapy was given. Target volume for HDR patients included the prostate with no expansion. Acute and chronic gastrointestinal (GI) toxicity was defined as occurring ≤ 6 and > 6 months, respectively, after radiotherapy and was graded per CTCAE version 3.0. Toxicity variables were analyzed with χ2 test. Results: Median follow-up was 7.5 years (7.4 years for EBRT and 7.9 years for HDR). 69.1% of EBRT patients received IMRT with the remainder treated using 3D conformal technique. Compared to EBRT, HDR was associated with decreased rates of acute grade ≥ 2 diarrhea (0.7% vs. 4.5%, p < 0.001), rectal pain/tenesmus (0.6% vs. 7.9%, p < 0.001), and rectal bleeding (0% vs. 1.6%, p=0.001). Rates of chronic grade ≥ 2 rectal bleeding (1.3% vs. 8.7%, p < 0.001) and radiation proctitis (0.9% vs. 3.3%, p=0.001) favored HDR over EBRT. Rates of any chronic rectal toxicity grade ≥ 2 were 2.4% vs. 10.5% (p < 0.001) for HDR vs. EBRT, respectively. For the 1478 EBRT patients treated with IMRT, acute and chronic rates of any grade ≥ 2GI toxicity were 4.2% and 5.6%, respectively, compared to 1.5% (p=0.002) and 2.4% (p=0.002), respectively, for HDR patients. Conclusions: In appropriately selected patients with localized prostate cancer undergoing definitive radiation therapy, HDR brachytherapy as monotherapy is an effective strategy for reducing acute and chronic rectal toxicity.


2021 ◽  
Vol 11 ◽  
Author(s):  
Jörg Tamihardja ◽  
Paul Lutyj ◽  
Johannes Kraft ◽  
Dominik Lisowski ◽  
Stefan Weick ◽  
...  

PurposeEvaluation of clinical outcome of two-weekly high-dose-rate brachytherapy boost after external beam radiotherapy (EBRT) for localized prostate cancer.Methods338 patients with localized prostate cancer receiving definitive EBRT followed by a two-weekly high-dose-rate brachytherapy boost (HDR-BT boost) in the period of 2002 to 2019 were analyzed. EBRT, delivered in 46 Gy (DMean) in conventional fractionation, was followed by two fractions HDR-BT boost with 9 Gy (D90%) two and four weeks after EBRT. Androgen deprivation therapy (ADT) was added in 176 (52.1%) patients. Genitourinary (GU)/gastrointestinal (GI) toxicity was evaluated utilizing the Common Toxicity Criteria for Adverse Events (version 5.0) and biochemical failure was defined according to the Phoenix definition.ResultsMedian follow-up was 101.8 months. 15 (4.4%)/115 (34.0%)/208 (61.5%) patients had low-/intermediate-/high-risk cancer according to the D`Amico risk classification. Estimated 5-year and 10-year biochemical relapse-free survival (bRFS) was 84.7% and 75.9% for all patients. The estimated 5-year bRFS was 93.3%, 93.4% and 79.5% for low-, intermediate- and high-risk disease, respectively. The estimated 10-year freedom from distant metastasis (FFM) and overall survival (OS) rates were 86.5% and 70.0%. Cumulative 5-year late GU toxicity and late GI toxicity grade ≥ 2 was observed in 19.3% and 5.0% of the patients, respectively. Cumulative 5-year late grade 3 GU/GI toxicity occurred in 3.6%/0.3%.ConclusionsTwo-weekly HDR-BT boost after EBRT for localized prostate cancer showed an excellent toxicity profile with low GU/GI toxicity rates and effective long-term biochemical control.


Sign in / Sign up

Export Citation Format

Share Document