A Comparison of Acute and Chronic Toxicity for Men With Low-Risk Prostate Cancer Treated With Intensity-Modulated Radiation Therapy or 125I Permanent Implant

Abstract

Purpose-To compare the toxicity and biochemical outcomes of intensity-modulated radiation therapy (IMRT) and 125 I transperineal permanent prostate seed implant ( 125 I) for patients with lowrisk prostate cancer.Methods and Materials-Between 1998 and 2004, a total of 374 low-risk patients (prostatespecific antigen < 10 ng/ml, T1c-T2b, Gleason score of 6 or less, and no neoadjuvant hormones) were treated at Fox Chase Cancer Center (216 IMRT and 158 125 I patients). Median follow-up was 43 months for IMRT and 48 months for 125 I. The IMRT prescription dose ranged from 74-78 Gy, and 125 I prescription was 145 Gy. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity was recorded by using a modified Radiation Therapy Oncology Group scale. Freedom from biochemical failure was defined by using the Phoenix definition (prostate-specific antigen nadir + 2.0 ng/ml).Results-Patients treated by using IMRT were more likely to be older and have a higher baseline American Urological Association symptom index score, history of previous transurethral resection of the prostate, and larger prostate volumes. On multivariate analysis, IMRT was an independent predictor of lower acute and late Grade 2 or higher GU toxicity and late Grade 2 or higher GI toxicity. Three-year actuarial estimates of late Grade 2 or higher toxicity were 2.4% for GI and 3.5% for GU by using IMRT compared with 7.7% for GI and 19.2% for GU for 125 I, respectively. Four-year actuarial estimates of freedom from biochemical failure were 99.5% for IMRT and 93.5% for 125 I (p = 0.09).Conclusions-The IMRT and 125 I produce similar outcomes, although IMRT appears to have less acute and late toxicity.

Brachytherapy Improves Biochemical Failure–Free Survival in Low- and Intermediate-Risk Prostate Cancer Compared With Conventionally Fractionated External Beam Radiation Therapy: A Propensity Score Matched Analysis

“…The rapid adoption of new RT practices as well as patient preference toward more convenient BT treatments are proposed explanations for the lack of comparative RT trials (13). A large number of retrospective studies have attempted to compare the treatment effectiveness of 2 or more RT modalities (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33). However, interpretation of this retrospective evidence can be challenging because very few studies make direct comparisons in homogenous GUROC low-or intermediate-risk patient populations.…”

Therapieoptionen für Patienten mit Niedrigrisiko-Prostatakarzinom

“…Bezüglich der Enddarmfunktion gibt es Hinweise, dass die LDR-Brachytherapie im Vergleich zur RT vorteilhafter ist [32]. Bei Anwendung der modernen IMRTTechnik scheint hingegen die gastrointestinale und urogenitale Akut-und Spätto-xizität gegenüber einer LDR-Brachytherapie verringert [13].…”

Equivalent Biochemical Control and Improved Prostate-Specific Antigen Nadir After Permanent Prostate Seed Implant Brachytherapy Versus High-Dose Three-Dimensional Conformal Radiotherapy and High-Dose Conformal Proton Beam Radiotherapy Boost

“…Although biologically comparable to photons in terms of cell kill efficacy, proponents have cited proton therapy's potential dosimetric advantage in reducing the integral dose to normal tissues (compared with photon EBRT techniques) as a justification for its use in the treatment of localized prostate cancer (6,9,28,30,31). PPI, however, delivers virtually no integral dose to extraprostatic tissues, with favorable long-term toxicity outcomes now well established in large, single and multi-institutional series (32)(33)(34)(35). Concerns regarding inter-and intrafractional organ motion are also eliminated with PPI, an inherent disadvantage to any EBRT technique, including proton therapy (36)(37)(38)(39).…”