American College of Radiology Appropriateness Criteria permanent source brachytherapy for prostate cancer

Use of a novel anthropomorphic prostate simulator in a prostate brachytherapy transrectal ultrasound imaging workshop for medical physicists

PURPOSE

Ultrasound imaging training is not required as part of radiation oncology training programs nor does any objective competency measure exist to independently assess performance. Physical simulation training can provide a structured approach to this training but only if suitably challenging training simulators exist. This study describes the design and preliminary evaluation of a simulation-based transrectal ultrasound (TRUS) imaging training workshop developed for medical physicists involved in low-dose-rate (LDR) prostate brachytherapy (PBT).

METHODS

The study incorporated novel high-fidelity anthropomorphic PBT TRUS training simulators and a TRUS imaging module with a blended-learning pedagogical approach, to address TRUS image optimisation and managing image quality.

RESULTS

Results demonstrated a significant improvement in knowledge, with an average increase in multiple choice question score of 61% (P < 0.0002), and that there was a 46% (P < 0.0001) average increase in the participants perceived understanding of TRUS scanner operation, and an increase of 36% (P < 0.001) in participants readiness to optimise image quality and mitigate image artefacts. Focus group data explored participants' experiences, perceptions and challenges with TRUS LDR PBT.

CONCLUSIONS

This study suggests a benefit in offering a simulation training workshop to medical physicists and the potential benefit to other healthcare professionals involved in prostate brachytherapy, by incorporating novel high-fidelity anthropomorphic PBT TRUS training simulators, in a simulated environment to practice ultrasound image optimisation for PBT image guidance. This approach to training would enable competency-based skill acquisition and continued proficiency or health professionals in the TRUS PBT procedure, outside of the surgical environment without direct exposure to patients.

Clinically Localized Prostate Cancer: AUA/ASTRO/SUO Guideline. Part II: Recommended Approaches and Details of Specific Care Options

PURPOSE

This guideline is structured to provide a clinical framework stratified by cancer severity to facilitate care decisions and guide the specifics of implementing the selected management options. The summary presented herein represents Part II of the two-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO/SUO Guideline discussing risk stratification and care options by cancer severity. Please refer to Part I for discussion of specific care options and outcome expectations and management.

MATERIALS AND METHODS

The systematic review utilized in the creation of this guideline was completed by the Agency for Healthcare Research and Quality and through additional supplementation by ECRI Institute. This review included articles published between January 2007 and March 2014 with an update search conducted through August 2016. When sufficient evidence existed, the body of evidence for a particular treatment was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. Additional information is provided as Clinical Principles and Expert Opinions (table 2 in supplementary unabridged guideline, http://jurology.com/).

RESULTS

The AUA (American Urological Association), ASTRO, and SUO (Society of Urologic Oncology) formulated an evidence-based guideline based on a risk stratified clinical framework for the management of localized prostate cancer.

CONCLUSIONS

This guideline attempts to improve a clinician's ability to treat patients diagnosed with localized prostate cancer, but higher quality evidence in future trials will be essential to improve the level of care for these patients. In all cases, patient preferences should be considered when choosing a management strategy.

The evolution of brachytherapy for prostate cancer

Brachytherapy (BT), using low-dose-rate (LDR) permanent seed implantation or high-dose-rate (HDR) temporary source implantation, is an acceptable treatment option for select patients with prostate cancer of any risk group. The benefits of HDR-BT over LDR-BT include the ability to use the same source for other cancers, lower operator dependence, and - typically - fewer acute irritative symptoms. By contrast, the benefits of LDR-BT include more favourable scheduling logistics, lower initial capital equipment costs, no need for a shielded room, completion in a single implant, and more robust data from clinical trials. Prospective reports comparing HDR-BT and LDR-BT to each other or to other treatment options (such as external beam radiotherapy (EBRT) or surgery) suggest similar outcomes. The 5-year freedom from biochemical failure rates for patients with low-risk, intermediate-risk, and high-risk disease are >85%, 69-97%, and 63-80%, respectively. Brachytherapy with EBRT (versus brachytherapy alone) is an appropriate approach in select patients with intermediate-risk and high-risk disease. The 10-year rates of overall survival, distant metastasis, and cancer-specific mortality are >85%, <10%, and <5%, respectively. Grade 3-4 toxicities associated with HDR-BT and LDR-BT are rare, at <4% in most series, and quality of life is improved in patients who receive brachytherapy compared with those who undergo surgery.

Permanent prostate brachytherapy pubic arch evaluation with diagnostic magnetic resonance imaging

PURPOSE

Pubic arch interference (PAI), when it occurs, is often a limiting factor for patients pursuing brachytherapy treatment of prostate cancer. Pre-brachytherapy pubic arch evaluation is often performed by CT or transrectal ultrasound (TRUS), but MRI has increasingly replaced these modalities for prostate cancer evaluation. The purpose of this study was to determine if staging MRI could be used to evaluate PAI and compare it with these other imaging methods.

METHODS AND MATERIALS

Forty-one consecutive patients undergoing brachytherapy evaluation had pelvic MRI-, CT-, and TRUS-based brachytherapy simulation. Pubic arch overlap on T2-weighted MRI and CT was determined by contouring the prostate gland on its largest axial slice and superimposing this contour onto the pubic arch bones. The largest degree of overlap of the prostate gland on MRI and CT was used to predict the existence of PAI as determined by TRUS-based simulation. The correlation between prostate contour overlap was also compared between MRI and CT.

RESULTS

Nineteen patients (48%) exhibited PAI on TRUS brachytherapy simulation evaluation. The average (±standard error) amount of prostate contour overlap on the pubic arch on CT was 2.9 ± 0.6 mm and on MRI was 2.0 ± 0.6 mm (linear correlation, R, of 0.783, p < 0.001). CT and MRI were equally predictive of PAI on TRUS evaluation (area under the curve = 0.75).

CONCLUSION

Pre-brachytherapy pubic arch assessment with diagnostic MRI provides similar predictability of PAI compared with CT, potentially obviating the need for additional pre-brachytherapy CT in the setting of staging MRI.

American Brachytherapy Society Task Group Report: Use of androgen deprivation therapy with prostate brachytherapy-A systematic literature review

PURPOSE

Prostate brachytherapy (PB) has well-documented excellent long-term outcomes in all risk groups. There are significant uncertainties regarding the role of androgen deprivation therapy (ADT) with brachytherapy. The purpose of this report was to review systemically the published literature and summarize present knowledge regarding the impact of ADT on biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS).

METHODS AND MATERIALS

A literature search was conducted in Medline and Embase covering the years 1996-2016. Selected were articles with >100 patients, minimum followup 3 years, defined risk stratification, and directly examining the role and impact of ADT on bPFS, CSS, and OS. The studies were grouped to reflect disease risk stratification. We also reviewed the impact of ADT on OS, cardiovascular morbidity, mortality, and on-going brachytherapy randomized controlled trials (RCTs).

RESULTS

Fifty-two selected studies (43,303 patients) were included in this review; 7 high-dose rate and 45 low-dose rate; 25 studies were multi-institutional and 27 single institution (retrospective review or prospective data collection) and 2 were RCTs. The studies were heterogeneous in patient population, risk categories, risk factors, followup time, and treatment administered, including ADT administration and duration (median, 3-12 months);71% of the studies reported a lack of benefit, whereas 28% showed improvement in bPFS with addition of ADT to PB. The lack of benefit was seen in low-risk and favorable intermediate-risk (IR) disease and most high-dose rate studies. A bPFS benefit of up to 15% was seen with ADT use in patients with suboptimal dosimetry, those with multiple adverse risk factors (unfavorable IR [uIR]), and most high-risk (HR) studies. Four studies reported very small benefit to CSS (2%). None of the studies showed OS advantage; however, three studies reported an absolute 5-20% OS detriment with ADT. Literature suggests that OS detriment is more likely in older patients or those with pre-existing cardiovascular disease. Four RCTs with an adequate number of patients and well-defined risk stratification are in progress. One RCT will answer the question regarding the role of ADT with PB in favorable IR patients and the other three RCTs will focus on optimal duration of ADT in the uIR and favorable HR population.

CONCLUSIONS

Patients treated with brachytherapy have excellent long-term disease outcomes. Existing evidence shows no benefit of adding ADT to PB in low-risk and favorable IR patients. UIR and HR patients and those with suboptimal dosimetry may have up to 15% improvement in bPFS with addition of 3-12 months of ADT, with uncertain impact on CSS and a potential detriment on OS. To minimize morbidity, one should exercise caution in prescribing ADT together with PB, in particular to older men and those with existing cardiovascular disease. Due to the retrospective nature of this evidence, significant selection, and treatment bias, no definitive conclusions are possible. RCT is urgently needed to define the potential role and optimal duration of ADT in uIR and favorable HR disease.

ACR appropriateness criteria: Permanent source brachytherapy for prostate cancer

PURPOSE

To provide updated American College of Radiology (ACR) appropriateness criteria for transrectal ultrasound-guided transperineal interstitial permanent source brachytherapy.

METHODS AND MATERIALS

The ACR appropriateness criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

RESULTS

Permanent prostate brachytherapy (PPB) is a treatment option for appropriately selected patients with localized prostate cancer with low to very high risk disease. PPB monotherapy remains an appropriate and effective curative treatment for low-risk prostate cancer patients demonstrating excellent long-term cancer control and acceptable morbidity. PPB monotherapy can be considered for select intermediate-risk patients with multiparametric MRI useful in evaluation of such patients. High-risk patients treated with PPB should receive supplemental external beam radiotherapy (EBRT) along with androgen deprivation. Similarly, patients with involved pelvic lymph nodes may also be considered for such combined treatment but reported long-term outcomes are limited. Computed tomography-based postimplant dosimetry completed within 60 days of PPB is essential for quality assurance. PPB may be considered for treatment of local recurrence after EBRT but is associated with an increased risk of toxicity.

CONCLUSIONS

Updated appropriateness criteria for patient evaluation, selection, treatment, and postimplant dosimetry are given. These criteria are intended to be advisory only with the final responsibility for patient care residing with the treating clinicians.

Comparative study of late rectal toxicity in prostate cancer patients treated with low-dose-rate brachytherapy: With or without supplemental external beam radiotherapy

PURPOSE

Supplemental external beam radiation therapy (sEBRT) is often prescribed in men undergoing low-dose-rate (LDR) brachytherapy. A population of patients was analyzed to assess the effect of sEBRT on late rectal toxicity. It was hypothesized that sEBRT + LDR would be associated with a higher risk of late rectal toxicity.

METHODS AND MATERIALS

This retrospective cohort study examined LDR brachytherapy patients, treated with or without sEBRT, with a minimum of 5-year followup. Longitudinal assessments were evaluated using the computerized patient record system. The Kaplan-Meier method was used for analysis.

RESULTS

Median followup was 7.5 years for 245 patients from 2004 to 2007. sEBRT was administered to 33.5%. Followup beyond 5 years was available for 89%. Overall rates of Grade ≥2 and ≥3 rectal toxicities were 6.9% and 2.9%, respectively. The risk of Grade ≥2 rectal toxicity was 2.8-fold higher for patients receiving sEBRT (95% confidence interval: 1.1-7.2; p = 0.02). The risk of Grade ≥3 rectal toxicity was 11.9-fold higher for patients who received sEBRT (1.5-97.4, 95% confidence interval; p = 0.003). Six of seven patients with a Grade ≥3 rectal toxicity received sEBRT, including one who required an abdominoperineal resection. Median post-LDR D90, V150, V200, and R100 values were 103.3%, 59.4%, 30.1%, and 0.5 cc.

CONCLUSIONS

In a cohort of LDR brachytherapy patients with high rates of followup, sEBRT + LDR was associated with significantly higher risk of Grade ≥2 and ≥3 late rectal toxicity. This analysis supports previous findings and maintains concern about the supplemental use of external beam radiation therapy with LDR brachytherapy while its benefit for tumor control has yet to be prospectively validated.

Establishing high-quality prostate brachytherapy using a phantom simulator training program

PURPOSE

To design and implement a unique training program that uses a phantom-based simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education.

METHODS AND MATERIALS

Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 ((125)I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis.

RESULTS

Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 >95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees' ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process.

CONCLUSIONS

Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB.

KRAS early testing: consensus initiative and cost-effectiveness evaluation for metastatic colorectal patients in an Italian setting

KRAS testing is relevant for the choice of the most appropriate first-line therapy of metastatic colorectal cancer (CRC). Strategies for preventing unequal access to the test should be implemented, but their relevance in the practice is related to economic sustainability. The study adopted the Delphi technique to reach a consensus on several topics. Issues related to execution of KRAS testing were identified by an expert’s board and proposed to 108 Italian oncologists and pathologists through two subsequent questionnaires. The emerging proposal was evaluated by decision analyses models employed by technology assessment agencies in order to assess cost-effectiveness. Alternative therapeutic strategies included most commonly used chemotherapy regimens alone or in combination with cetuximab or bevacizumab. The survey indicated that time interval for obtaining KRAS test should not exceed 15 days, 10 days being an optimal interval. To assure the access to proper treatment, a useful strategy should be to anticipate the test after radical resection in patients at high risk of relapse. Early KRAS testing in high risk CRC patients generates incremental cost-effectiveness ratios between 6,000 and 13,000 Euro per quality adjusted life year (QALY) gained. In extensive sensitivity analyses ICER’s were always below 15,000 Euro per QALY gained, far within the threshold of 60,000 Euro/QALY gained accepted by regulatory institutions in Italy. In metastatic CRC a time interval higher than 15 days for result of KRAS testing limits access to therapeutic choices. Anticipating KRAS testing before the onset of metastatic disease in patients at high risk does not affect the sustainability and cost-effectiveness profile of cetuximab in first-line mCRC. Early KRAS testing may prevent this inequality in high-risk patients, whether they develop metastases, and is a cost-effective strategy. Based on these results, present joined recommendations of Italian societies of Oncology and Pathology should be updated including early KRAS testing.

MRI-based sector analysis enhances prostate palladium-103 brachytherapy quality assurance in a phase II prospective trial of men with intermediate-risk localized prostate cancer

PURPOSE

Palladium-103 ((103)Pd) may be superior to other isotopes in brachytherapy for localized intermediate-risk prostate cancer because of its relatively short half-life, higher initial dose rate, and greater dose heterogeneity within the target volume; these properties also underscore the need for accurate target delineation and postimplant quality assurance. We assessed the use of prostate sector analysis based on MRI for quality assurance after (103)Pd monotherapy.

METHODS AND MATERIALS

Fifty men with intermediate-risk prostate cancer underwent (103)Pd monotherapy in a prospective phase II trial at MD Anderson Cancer Center. Dosimetric analyses on day 30 after the implant were done using both CT and fused CT/MRI scans. Dosimetric variables were assessed for the entire prostate and for each of three or six sectors. Volumes and dosimetric variables were compared with paired t tests.

RESULTS

Postimplant dosimetric variables for the entire prostate were significantly different on CT vs. CT/MRI (p = 0.019 for V100 and p < 0.01 for D90). Prostate volumes were smaller on the CT/MRI scans (p < 0.00001). The base sector contributed the greatest difference, with doses based on CT/MRI lower than those based on CT (p < 0.01 for V100 and D90). To date, these lower base doses have not affected biochemical outcomes for patients with disease in prostate base biopsy samples.

CONCLUSIONS

CT/MRI is more precise than CT for prostate volume delineation and dosimetric quality assessment and thus provides superior heterogeneity control assessment after (103)Pd monotherapy implants.

Dosimetric influence of seed spacers and end-weld thickness for permanent prostate brachytherapy

PURPOSE

The aim of this study was to analyze the dosimetric influence of conventional spacers and a cobalt chloride complex contrast (C4) agent, a novel marker for MRI that can also serve as a seed spacer, adjacent to (103)Pd, (125)I, and (131)Cs sources for permanent prostate brachytherapy.

METHODS AND MATERIALS

Monte Carlo methods for radiation transport were used to estimate the dosimetric influence of brachytherapy end-weld thicknesses and spacers near the three sources. Single-source assessments and volumetric conditions simulating prior patient treatments were computed. Volume-dose distributions were imported to a treatment planning system for dose-volume histogram analyses.

RESULTS

Single-source assessment revealed that brachytherapy spacers primarily attenuated the dose distribution along the source long axis. The magnitude of the attenuation at 1 cm on the long axis ranged from -10% to -5% for conventional spacers and approximately -2% for C4 spacers, with the largest attenuation for (103)Pd. Spacer perturbation of dose distributions was less than manufacturing tolerances for brachytherapy sources as gleaned by an analysis of end-weld thicknesses. Volumetric Monte Carlo assessment demonstrated that TG-43 techniques overestimated calculated doses by approximately 2%. Specific dose-volume histogram metrics for prostate implants were not perturbed by inclusion of conventional or C4 spacers in clinical models.

CONCLUSIONS

Dosimetric perturbations of single-seed dose distributions by brachytherapy spacers exceeded 10% along the source long axes adjacent to the spacers. However, no dosimetric impact on volumetric parameters was noted for brachytherapy spacers adjacent to (103)Pd, (125)I, or (131)Cs sources in the context of permanent prostate brachytherapy implants.

Biochemical outcomes for patients with intermediate risk prostate cancer treated with I-125 interstitial brachytherapy monotherapy

BACKGROUND AND PURPOSE

Routine use of I-125 interstitial brachytherapy (BT) alone in intermediate risk (IR) prostate cancer is controversial. It is often combined with external beam radiotherapy (EBRT). The biochemical outcome of a large cohort of only IR disease treated with BT monotherapy is reported.

MATERIALS AND METHODS

Between 2003 and 2007, 615 patients with Memorial Sloan-Kettering Cancer Centre (MSKCC) defined IR disease (one risk factor only-T2b, or Gleason score (GS) 7, or raised initial PSA (iPSA) 10.1-20ng/ml) were treated with BT monotherapy. ASTRO (3 consecutive rises) and Phoenix (nadir plus 2) criteria defined biochemical failure. Potential prognostic factors (pre- and post-implant dosimetric indices, GS 3+4 versus 4+3, androgen deprivation therapy (ADT)) were analysed.

RESULTS

Median follow-up was 5.0years. Forty-three patients had stage T2b, 180 had raised iPSA, 392 had GS 7 disease. ADT was received by 108 patients. The 5-year biochemical no evidence of disease (bNED) rates are 87.3% (by ASTRO), 88.6% (by Phoenix). Stratification by risk factor (T2b, GS7, raised iPSA) demonstrated raised iPSA to have poorer outcome only by Phoenix criteria (p=0.0002). Other potential prognostic variables were non-significant.

CONCLUSION

Good rates of biochemical control can be achieved in the medium term with BT monotherapy in IR disease. Raised iPSA correlated with a poorer outcome.

Practice-based evidence to evidence-based practice: building the National Radiation Oncology Registry

The National Radiation Oncology Registry (NROR), sponsored by the Radiation Oncology Institute and the American Society for Radiation Oncology, is designed to collect standardized information on cancer care delivery among patients treated with radiotherapy in the United States and will focus on patients with prostate cancer. Stakeholders were engaged through a forum that emphasized the need for patient-centered outcomes, minimal data burden, and maximal connectivity to existing registries and databases. An electronic infrastructure is under development to provide connectivity across radiation oncology and hospital information systems. The NROR Gateway features automatic abstraction as well as aggregation of treatment and outcome data. The prostate cancer data dictionary provides standardized elements in four domains: facility, physician, patient, and treatment. The pilot phase will consist of clinical centers chosen to provide a representative mix of radiation treatment modalities, facility types, population-based settings, and regional locations. The initial set of radiation practice metrics includes physician board certification and maintenance, ordering of staging scans, active surveillance discussion, dose prescriptions for low-risk/high-risk disease, radiation fields for low-risk/high-risk disease, image-guided radiation therapy use, androgen deprivation therapy use, post-brachytherapy implant computed tomography dosimetry, collection of toxicity assessments, and longitudinal patient follow-up. The NROR pilot study will provide the framework for expansion to a nationwide electronic registry for radiation oncology.

Progressive transition from pre-planned to intraoperative optimizing seed implant: post implementation analysis

Purpose

To perform a dosimetric comparison between a pre-planned technique and a pre-plan based intraoperative technique in prostate cancer patients treated with I-125 permanent seed implantation.

Material and methods

Thirty patients were treated with I-125 permanent seed implantation using TRUS guidance. The first 15 of these patients (Arm A) were treated with a pre-planned technique using ultrasound images acquired prior to seed implantation. To evaluate the reproducibility of the prostate volume, ultrasound images were also acquired during the procedure in the operating room (OR). A surface registration was applied to determine the 6D offset between different image sets in arm A. The remaining 15 patients (Arm B) were planned by putting the pre-plan on the intraoperative ultrasound image and then re-optimizing the seed locations with minimal changes to the pre-plan needle locations. Post implant dosimetric analyses included comparisons of V₁₀₀(prostate), D₉₀(prostate) and V₁₀₀(rectum).

Results

In Arm A, the 6D offsets between the two image sets were θ_x=−1.4±4.3; θ_y=−1.7±2.6; θ_z=−0.5±2.6; X=0.5±1.8 mm; Y=−1.3±−3.5 mm; Z=−1.6±2.2 mm. These differences alone degraded V₁₀₀ by 6.4% and D₉₀ by 9.3% in the pre-plan, respectively. Comparing Arm A with Arm B, the pre-plan based intraoperative optimization of seed locations used in the plans for patients in Arm B improved the V₁₀₀ and D₉₀ in their post-implant studies by 4.0% and 5.7%, respectively. This was achieved without significantly increasing the rectal dose (V₁₀₀(rectum)).

Conclusions

We have progressively moved prostate seed implantation from a pre-planned technique to a pre-plan based intraoperative technique. In addition to reserving the advantage of cost-effective seed ordering and efficient OR implantation, our intraoperative technique demonstrates increased accuracy and precision compared to the pre-planned technique.

American Society of Clinical Oncology Clinical Practice Guidelines: formal systematic review-based consensus methodology

The American Society of Clinical Oncology (ASCO) guidelines program employs a systematic review-based methodology to produce evidence-based guidelines. This is consistent with the stance of the Institute of Medicine on guideline development, which is that high-quality evidence syntheses form the basis for recommendation development. In the absence of high-quality evidence, recommendation development becomes more complex. One option is to provide no recommendations or withdraw a guideline topic. However, it is often the areas of greatest uncertainty in which the evidentiary base is incomplete, and thus, guidelines are needed most. To provide recommendations in such circumstances, an explicit methodology is needed to ensure that a credible process is undertaken, and rigorous, reliable advice is provided. In 2010, the ASCO Board of Directors approved development of guideline recommendations using consensus methodology. A modified Delphi approach to recommendation development, based on the best available data identified in a systematic review, was piloted with an ASCO guideline. Consensus was achieved through the rating of a series of recommendations by a large group of clinicians, including academic and community-based content and methodology experts. A prespecified threshold of agreement was determined to indicate when consensus was achieved. Consensus was defined as agreement by ≥ 75% of raters. The formal consensus methodology used by ASCO enabled development of guideline recommendations on a challenging clinical issue based on limited evidence using a rigorous, transparent, and explicit method. This methodology is proposed for development of future ASCO guidelines on topics for which limited evidence is available.

Endorectal magnetic resonance imaging for predicting pathologic T3 disease in Gleason score 7 prostate cancer: implications for prostate brachytherapy

PURPOSE

To determine the ability of endorectal magnetic resonance imaging (erMRI) and other pretreatment factors to predict the presence and extent of extraprostatic extension (EPE) in men with Gleason score (GS) 7 prostate cancer.

METHODS AND MATERIALS

We included patients with clinical stage T1c-T2c, GS=7 (3+4 or 4+3), and prostate-specific antigen (PSA) <10ng/mL who underwent pre-prostatectomy erMRI. We compared pathologic EPE findings with pretreatment factors.

RESULTS

One hundred seventy-one men were eligible for inclusion. Pretreatment characteristics were: median age=60 years (42-76); median PSA 4.9ng/mL (0.4-9.9); GS 3+4=61%; T1c=51%; T2a=25%; T2b=21%; T2c=3%; ≥50% positive cores=46%; EPE-positive (EPE+) erMRI=28%. Thirty-three percent had pathologic EPE. Increasing T-stage (p<0.0001) and EPE+ erMRI (p<0.0001) were significant predictors of pathologic EPE, whereas GS (4+3 vs. 3+4) (p=0.14), percentage of positive core biopsies (p=0.15), and pretreatment PSA (p=0.41) were not. Median EPE distance was 1.75mm (range, <1-15mm). The rates of EPE >5mm and EPE >3mm were 11% and 15%, respectively. The odds ratios for erMRI detection of any EPE and of EPE >5mm were 3.06 and 3.75, respectively.

CONCLUSIONS

T-stage and EPE+ erMRI predict pathologic EPE in men with GS 7 prostate cancer. The ability of erMRI to detect EPE increases with increasing EPE distance. These findings may be useful in patient selection for prostate brachytherapy monotherapy.

A survey of current clinical practice in permanent and temporary prostate brachytherapy: 2010 update

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.

Image guided, adaptive, accelerated, high dose brachytherapy as model for advanced small volume radiotherapy

Brachytherapy has consistently provided a very conformal radiation therapy modality. Over the last two decades this has been associated with significant improvements in imaging for brachytherapy applications (prostate, gynecology), resulting in many positive advances in treatment planning, application techniques and clinical outcome. This is emphasized by the increased use of brachytherapy in Europe with gynecology as continuous basis and prostate and breast as more recently growing fields. Image guidance enables exact knowledge of the applicator together with improved visualization of tumor and target volumes as well as of organs at risk providing the basis for very individualized 3D and 4D treatment planning. In this commentary the most important recent developments in prostate, gynecological and breast brachytherapy are reviewed, with a focus on European recent and current research aiming at the definition of areas for important future research. Moreover the positive impact of GEC-ESTRO recommendations and the highlights of brachytherapy physics are discussed what altogether presents a full overview of modern image guided brachytherapy. An overview is finally provided on past and current international brachytherapy publications focusing on "Radiotherapy and Oncology". These data show tremendous increase in almost all research areas over the last three decades strongly influenced recently by translational research in regard to imaging and technology. In order to provide high level clinical evidence for future brachytherapy practice the strong need for comprehensive prospective clinical research addressing brachytherapy issues is high-lighted.