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Purpose To determine whether computed tomography/magnetic resonance imaging–based day 0 (d0) dosimetry is a meaningful predictor of day 21 (d21) dosimetry in low-dose-rate brachytherapy for localized prostate cancer. Methods and Materials The study population consisted of 277 men with localized (T1-2 N0 M0), low-/intermediate-risk prostate cancer treated with low-dose-rate brachytherapy. Computed tomography/magnetic resonance imaging fusion was used for postimplant dosimetry at d0 and d21. Logistic regression was used to construct receiver operating characteristic curves for achieving each constraint at d21, based on d0 D90 and V100, and Youden’s index was used to evaluate cutpoints. Freedom from biochemical failure (FBCF) was estimated with the Kaplan-Meier method. Results The median d0 D90 increased from 133 to 150 Gy at d21, and median d0 V100 increased from 87% to 91%. For achieving the D90 constraint at d21, the optimal cut-point for d0 D90 was 135 Gy, with 84% of these patients maintaining a d21 D90 > 145 Gy. For achieving the D90 constraint at d21, the optimal cut-point for d0 V100 was 87%, with 83% of these patients maintained a d21 V100 > 90%. There was no improvement in FBCF in patients with a d0 D90 > 135 Gy or D90 > 145 Gy. Similarly, there was no improvement in FBCF in patients with a d0 V100 > 87% or V100 > 90%. Conclusions Meeting dosimetric constraints on d0 does not obviate d21 dosimetric analysis. Constraints used for dose prescriptions on d0 are not the ideal predictors of d21 dosimetry.

Purpose To evaluate patient characteristics and dosimetric parameters that predict biochemical failure (BCF) after real-time planned low-dose-rate prostate brachytherapy. Methods From 1998 to 2008, a low-risk cohort by National Comprehensive Cancer Network criteria of 341 men with a median followup of 41.6 months was analyzed. This cohort had a median age of 65.1 years, prostate volume of 35.8 cc, and pretreatment prostate-specific antigen of 5.6 ng/mL. Patients had predominately Gleason 6 (95.9%) and T1c (81.3%) disease. About 3.6% of the patients received androgen deprivation therapy. Kaplan–Meier and Cox proportional hazards survival analysis methods were used to analyze predictors of BCF (Phoenix definition). Results At 72 months, freedom from BCF was 91.1% (95% confidence interval = 85.0–94.8). The median D90 was 145.9 Gy, and the median V100 was 90.3%. Because of infrequent BCF, the following prostate volume groups were examined: 15–

Purpose To describe a novel technique that integrates customized sleeved seed production to reduce seed migration using preloaded needles with real-time intraoperative dosimetric planning for patients treated with iodine-125 (I-125) permanent prostate seed implants. Methods and Materials Customized seed-spacer sequences were calculated for patients in real time based on an intraoperative transrectal ultrasound-guided volume study. Using a Fox Chase Cancer Center modified Best Iodine-125 seed loader (Best Medical, Springfield, VA), the seeds and spacers were inserted into a hollow suture material (sleeve) and then loaded into the implant needles. Needles were placed sequentially under transrectal ultrasound guidance with sagittal plane visualization of the dropped sleeved seeds. Results This technique was successfully implemented allowing intraoperative planning to be combined with real-time sleeved seed production. Conclusions The use of sleeves for seeds combined with real-time intraoperative planning allowed for the intraoperative customization of implants with the practical advantages of linked seeds.

Purpose To determine the impact of fellow, resident, or medical student (MS) involvement on outcomes in patients undergoing permanent 125 I prostate seed implant. Methods and Materials The study population consisted of men with clinically localized low/intermediate-risk prostate cancer treated with low-dose-rate permanent interstitial brachytherapy. Cases were stratified according to resident, fellow, MS, or attending involvement. Outcomes were compared using analysis of variance, logistic regression, and log rank tests. Results A total of 291 patients were evaluated. Fellows, residents, and MS were involved in 47 (16.2%), 231 (79.4%), and 34 (11.7%) cases, respectively. Thirteen (4.4%) cases were completed by an attending physician alone. There was no difference in freedom from biochemical failure when comparing the resident, fellow, or attending alone groups ( p = 0.10). There was no difference in V 100 (volume of the prostate receiving 100% of the prescription dose) outcomes when comparing resident cases to fellow cases ( p = 0.72) or attending alone cases ( p = 0.78). There was no difference in D 90 (minimum dose covering 90% of the postimplant volume) outcomes when comparing resident cases to fellow cases ( p = 0.74) or attending alone cases ( p = 0.58). When examining treatment toxicity, fellow cases had higher rates of acute Grade 2 + GU toxicity ( p = 0.028). With the exception of higher urethra D 90 among PGY 2–3 cases ( p = 0.02), dosimetric outcomes were similar to cases with PGY 4–5 resident participation. There was no difference in outcomes for cases with and without MS participation. Conclusions Interstitial prostate seed implants can be safely performed by trainees with appropriate supervision. Hands-on brachytherapy training is effective and feasible for trainees.

Purpose To help establish patterns of care and standards of care of interstitial permanent low-dose-rate (LDR) and temporary high-dose-rate brachytherapy for prostate cancer and to compare the results with a similar 1998 American Brachytherapy Society (ABS) survey. Methods and Materials A comprehensive questionnaire intended to survey specific details of current clinical brachytherapy practice was provided to the participants of the seventh ABS Prostate Brachytherapy School. Responses were tabulated and descriptive statistics are reported. Results Sixty-five brachytherapy practitioners responded to the survey. Eighty-nine percent (89%) of respondents performed LDR and 49% perform high-dose-rate brachytherapy. The median number of years of experience for LDR brachytherapists increased from 5 to 10 years over the course of the 12 years since the preceding survey. Compared with the first ABS, a smaller proportion of respondents received formal brachytherapy residency training (43% vs. 56%) or formal “hands-on” brachytherapy training (15% vs. 63%). There has been a marked decline in the utilization of the Mick applicator (Mick Radio-Nuclear Instruments, Inc., Mount Vernon, NY, USA) (60% vs. 28%) and an increase in the use of stranded seeds (40% vs. 11%). Compliance with postimplant dosimetry was higher in the 2010 survey. Conclusion This survey does suggest an evolution in the practice of LDR brachytherapy since 1998 and aids in identifying aspects that require further progress or investigation. ABS guidelines and other practice recommendations appear to impact the practice of brachytherapy.

PURPOSE: To provide updated American Brachytherapy Society (ABS) guidelines for transrectal ultrasound-guided transperineal interstitial permanent prostate brachytherapy (PPB). METHODS AND MATERIALS: TheABSformedacommitteeofbrachytherapistsandresearchers experienced in the clinical practice of PPBto formulate updated guidelines for this technique. Sources of input for these guidelines included prior published guidelines, clinical trials, published literature, andexperienceofthecommittee.Therecommendationsofthecommitteewerereviewedandapproved by the Board of Directors of the ABS. RESULTS: Patients with high probability of organ-confined disease or limited extraprostatic exten- sion are considered appropriate candidates for PPB monotherapy. Low-risk patients may be treated with PPB alone without the need for supplemental external beam radiotherapy. High-risk patients should receive supplemental external beam radiotherapy if PPB is used. Intermediate-risk patients should be considered on an individual case basis. Intermediate-risk patients with favorable features may appropriately be treated with PPB monotherapy but results from confirmatory clinical trials are pending. Computed tomographyebased postimplant dosimetry performed within 60 days of the implant is considered essential for maintenance of a satisfactory quality assurance program. Postim- plantcomputedtomographyemagneticresonanceimagefusionisviewedasuseful,butnotmandatory. CONCLUSIONS: Updated guidelines for patient selection, workup, treatment, postimplant dosim- etry, and followup are provided. These recommendations are intended to be advisory in nature with the ultimate responsibility for the care of the patients resting with the treating physicians. 2012 Published by Elsevier Inc. on behalf of American Brachytherapy Society. All rights reserved.