High-dose-rate brachytherapy for large prostate volumes (> or =50cc)-Uncompromised dosimetric coverage and acceptable toxicity.

PURPOSE: The purpose of this study was to review our single-institution experience using high-dose-rate (HDR) brachytherapy in patients with large-volume prostate glands (> or =50cc). METHODS AND MATERIALS: Fifty-four patients treated with HDR brachytherapy for prostate cancer at the Penrose Cancer Center between 2001 and 2006 were identified as having an ultrasound volume of at least 50cc at the time of implant (range, 50-97.3cc; mean, 61.5cc; median, 57cc; upper quartile, 83.3-97.3cc). Neoadjuvant hormones (17 patients) were not routinely recommended unless the initial ultrasound volume suggested pubic arch interference or the patient's Gleason score or prostate specific antigen prompted use. All patients received HDR brachytherapy as a boost before or after conformal external beam radiation therapy to 4500cGy. Boost brachytherapy doses ranged from 1600 to 1900cGy, given in two to three fractions. RESULTS: The median D(90) (minimal dose to 90% of the prostate) was 109% of prescription dose (range, 95-115%) and the median V(100) (volume receiving 100% of the dose) was 96% (range, 90-99%). V(150) ranged from 10% to 35%, with a median value of 18.3%. Six patients (11%) required temporary placement of a urinary catheter for acute obstructive symptoms after brachytherapy. With a median followup of 1.8 years, there has been a single case of Grade 2 gastrointestinal toxicity and 1 patient has developed a bulbo-urethral stricture requiring dilation. There have been no cases of rectal bleeding. CONCLUSIONS: Large prostate volume is not a contraindication to HDR brachytherapy. Excellent dosimetric coverage can be attained with acceptable acute toxicity.

Low morbidity following high dose rate brachytherapy in the setting of prior transurethral prostate resection.

PURPOSE: We reviewed our single institution experience with high dose rate brachytherapy in patients who underwent prior transurethral prostate resection. MATERIALS AND METHODS: A total of 28 patients treated with high dose rate brachytherapy for prostate cancer at our institution between 2001 and 2006 were identified as having undergone prior transurethral prostate resection. All patients received high dose rate brachytherapy as a boost before or after conformal external beam radiation therapy to 4,500 cGy. Boost brachytherapy doses ranged from 1,600 to 1,900 cGy, given in 2 or 3 fractions. Changes in American Urological Association symptom scores were assessed. RESULTS: Dosimetric goals were adequately achieved in all patients with a median minimal dose to 90% of the prostate of 109% of the prescription dose (range 100% to 117%). The median volume receiving 100% of the prescribed dose was 95% (range 87.9% to 100%) Three patients (11%) required temporary urinary catheter placement for acute obstructive symptoms after brachytherapy. At a median followup of 2.5 years there was 1 case each of grade 1 rectal proctitis, grade 1 hemorrhage and grade 2 cystitis. Two patients had worsening of existing grade 1 urge incontinence to grade 2. No patient had a bulbourethral stricture requiring dilation or new onset incontinence. Patients with a higher baseline American Urological Association score demonstrated significantly improved scores over those with lower baseline scores (less than 15) at least 1 year after treatment. CONCLUSIONS: High dose rate brachytherapy with careful attention to dosimetry is a reasonable treatment option for patients who have undergone prior transurethral prostate resection with the expectation of low morbidity.