Acute urinary morbidity following I-125 interstitial implantation of the prostate gland

New sparse implantation technique of I-125 low-dose-rate brachytherapy using concomitant short-term hormonal treatment for low and intermediate-risk prostate cancer: An initial study of therapeutic feasibility

This study aimed to evaluate the oncological outcomes and post-implantation complications of the concurrent androgen deprivation therapy (ADT) with I-125 low-dose-rate (LDR)-prostate brachytherapy (sparse implantation technique: SIT) in comparison with the conventional non-ADT using whole gland brachytherapy (CWT). 302 localized prostate cancer (PCa) patients were treated with CWT (implantation dose: 145 Gy) and 215 patients were treated with SIT, which applied reduced implantation dose of 123.5 Gy. SIT group had ADT consisting of bicalutamide 50 mg/day plus 3-month depot (11.25 mg) of leuprolide acetate subcutaneously on the post-implantation day-0. Post-implantation complications and biochemical-recurrence-free-survival (BCRS) were compared between the two groups. After ADT, SIT group had 40.9% patients (40.9%) with prostate volume reduction between 20–30%. At 3-months post-implantation, SIT group presented significantly better IPSS than CWT group (p = 0.038). Both groups showed decrease in IIEF-5 score at 3-months post-implantation, but ST group showed significantly better mean IIEF-5 scores (13.5) than the CWT group (11.1) (p = 0.045). For 3-months post-implantation dosimetry, both groups showed no significant differences regarding D90 (CWT 156 Gy vs. SIT 152 Gy). CWT group had 3 patients with rectal toxicity ≥radiation therapy oncology group (RTOG) grade 2 and 1 patient with urinary toxicity ≥RTOG grade 2 whereas SIT group had no patient with urinary or rectal toxicity ≥RTOG grade 2. Kaplan-Meier analyses showed no significant differences regarding PCSS were observed between the two groups (p = 0.350). The SIT group showed compatible oncological outcomes to the CWT and relatively smaller number of post-implantation complications within low- and intermediate-risk PCa patients.

Thirty-day hospital revisits after prostate brachytherapy: who is at risk?

BACKGROUND

Transperineal prostate brachytherapy is a common outpatient procedure for the treatment of prostate cancer. Whereas long-term morbidity and toxicities are widely published, rates of short-term complications leading to hospital revisits have not been well described.

MATERIALS AND METHODS

Patients who underwent brachytherapy for prostate cancer in an ambulatory setting were identified in the Healthcare Cost and Utilization Project State Ambulatory Surgery Database for California between 2007 and 2011. Emergency department (ED) visits and inpatient admissions within 30 days of treatment were determined from the California Healthcare Cost and Utilization Project State Emergency Department Database and State Inpatient Database, respectively.

RESULTS

Between 2007 and 2011, 9,042 patients underwent brachytherapy for prostate cancer. Within 30 days postoperatively, 543 (6.0%) patients experienced 674 hospital encounters. ED visits comprised most encounters (68.7%) at a median of 7 days (interquartile range 2-16) after surgery. Inpatient hospitalizations occurred on 155 of 674 visits (23.0%) at a median of 12 days (interquartile range 5-20). Common presenting diagnoses included urinary retention, malfunctioning catheter, hematuria, and urinary tract infection. Logistic regression demonstrated advanced age {65-75 years: odds ratio [OR], 1.3 [95% confidence interval (CI) 1.06-1.60, P = 0.01]; >75 years: OR 1.5 [95% CI 1.18-1.97, P = 0.001]}, inpatient admission within 90 days before surgery [OR 2.68 (95% CI 1.8-4.0, P < 0.001)], and ED visit within 180 days before surgery [OR 1.63 (95% CI 1.4-1.89, P < 0.001)] as factors that increased the risk of hospital-based evaluation after outpatient brachytherapy. Charlson comorbidity score did not influence risk.

CONCLUSIONS

ED visits and inpatient admissions are not uncommon after prostate brachytherapy. Risk of revisit is higher in elderly patients and those who have had recent inpatient or ED encounters.

Three-Dimensional Conformal External Beam Radiotherapy versus the Combination of External Radiotherapy with High-Dose Rate Brachytherapy in Localized Carcinoma of the Prostate: Comparison of Acute Toxicity

Aims and background

Radiotherapy represents one of the basic therapeutic methods in treatment of localized carcinoma of the prostate. Optimal irradiation dose is the cornerstone of a successful treatment. Along with local control of the disease and overall survival of the patient, possible acute and long-term side effects need to be monitored very closely.

Methods

A non-randomized prospective study comparing the acute genitourinary and gastrointestinal toxicity in patients irradiated for localized carcinoma of the prostate. Fifty-seven patients were treated with three-dimensional conformal external beam radiotherapy alone, and in the second treatment arm a combination of external beam radiotherapy and high-dose rate brachytherapy was employed in 40 patients.

Results

Three-dimensional conformai external beam radiotherapy. Acute G1 genitourinary toxicity was recorded in 35.1% of patients, G2 in 22.8%, and G2-3 in one patient (1.7%). Acute gastrointestinal toxicity was experienced by 54.4% of patients, G1 in 28.1%, G2 in 17.5%, and G3 in 8.8%. Three-dimensional conformal external beam radiotherapy + brachytherapy. Acute G1 genitourinary toxicity was recorded in 37.5% and grade 2 in 15% of the patients. Only G1 acute gastrointestinal toxicity was recorded in 40% of the patients.

Conclusions

Acute G1 genitourinary toxicity was experienced by a similar percentage of patients in both treatment arms. Acute G2 genitourinary toxicity was more frequent in the three-dimensional conformal radiotherapy arm. Higher acute genitourinary toxicity, G3 or G4, was recorded only in one patient per treatment arm. Acute gastrointestinal toxicity was more frequent in the three-dimensional conformal radiotherapy arm. Higher acute gastrointestinal toxicity, G2 and G3, was only observed in the three-dimensional conformal radiotherapy arm. The acute toxicity observed was of a low grade. The combination of external beam radiotherapy with brachytherapy resulted in a lower incidence of gastrointestinal toxicity than external beam radiotherapy alone.

Evaluation of intraoperative magnetic resonance imaging/ultrasound fusion optimization for low-dose-rate prostate brachytherapy

Purpose

Intraoperative planning with transrectal ultrasound (US) is used for accurate seed placement and optimal dosimetry in prostate brachytherapy. However, prostate magnetic resonance imaging (MRI) has shown superiority in delineation of prostate anatomy. Accordingly, MRI/US fusion may be useful for accurate intraoperative planning. We analyzed planning with MRI/US fusion to compare differences in dosimetry and volume to that derived from the postoperative computed tomography (CT).

Material and methods

Twenty patients underwent preoperative prostate MRI, which was fused intraoperatively with US during prostate brachytherapy. Intraoperative ¹²⁵I or ¹⁰³Pd seed placement was modified by the use of MRI fusion when indicated. Following implantation, dose comparisons were made between data derived from MRI/US and that from post-operative CT scans. Plan parameters analyzed included the D₉₀ (dose to 90% of the prostate), rectal D₃₀, V₃₀ (volume of the rectum receiving 30 percent of dose), and prostate V₁₀₀.

Results

The median number of seeds implanted per patient was seventy-six. The MRI measured prostate volume, which was on average 4.47 cc larger than the CT measured prostate volume. In 9 patients, the apex of the prostate was better identified under MRI with the fusion protocol, and an average of 4 fewer seeds were required to be placed in the apex/urinary sphincter region. Both MRI and US individually showed a reduced intraoperative prostate D₉₀ in comparison to the postoperative CT, with a larger mean difference for MRI in comparison with US (9.71 vs. 4.31 Gy, p = 0.007). This was also true for the prostate V₁₀₀ (5.18 vs. 2.73 cc, p = 0.009). Post-operative CT underestimated rectal D₃₀ and V₃₀ in comparison to both MRI and US with MRI showing a larger mean difference than US for D₃₀ (40.64 vs. 35.92 Gy, p = 0.04) and V₃₀ (50.20 vs. 44.38 cc, p = 0.009).

Conclusions

The MRI/US fusion demonstrated greater prostate volume compared to standard CT/US based planning likely due to the better resolution of the prostate apex. Furthermore, rectal dose was underestimated with CT vs. MRI based planning. Additional study is required to assess long-term clinical implications of disease control and effects on long-term toxicity, especially as related to the rectum and urinary sphincter. MRI/US intraoperative fusion may improve prostate dosimetry while sparing the rectum and urethra, potentially impacting disease control and late toxicity.

Three-dimensional dose prediction and validation with the radiobiological gamma index based on a relative seriality model for head-and-neck IMRT

This study proposes a quality assurance (QA) method incorporating radiobiological factors based on the QUANTEC-determined tumor control probability and the normal tissue complication probability (NTCP) of head-and-neck intensity-modulated radiation therapy (HN-IMRT). Per-beam measurements were conducted for 20 cases using a 2D detector array. Three-dimensional predicted dose distributions within targets and organs at risk were reconstructed based on the per-beam QA results derived from differences between planned and measured doses. Under the predicted dose distributions, the differences between the physical and radiobiological gamma indices (PGI and RGI, respectively) based on the relative seriality (RS) model were evaluated. The NTCP values in the RS and Niemierko models were compared. The dose covers 98% (D98%) of the clinical target volume (CTV) decreased by 3.2% (P < 0.001), and the mean dose of the ipsilateral parotid increased by 6.3% (P < 0.001) compared with the original dose. RGI passing rates in the CTV and brain stem were greater than PGI ones by 5.8% (P < 0.001) and 2.0% (P < 0.001), respectively. The RS model's average NTCP values for the ipsilateral and contralateral parotids under the original dose were smaller than those of the Niemierko model by 9.0% (P < 0.001) and 7.0% (P < 0.001), respectively. The 3D predicted dose evaluation with RGI based on the RS model was introduced for QA of HN-IMRT, leading to dose evaluation for each organ with consideration of the radiobiological effect. This method constitutes a rational way to perform QA of HN-IMRT in clinical practice.

Assessment of lower urinary symptom flare with overactive bladder symptom score and International Prostate Symptom Score in patients treated with iodine-125 implant brachytherapy: long-term follow-up experience at a single institute

Background

The aim of this study was to evaluate the combined use of the overactive bladder symptom score (OABSS) and International Prostate Symptom Score (IPSS) as an assessment tool for urinary symptom flare after iodine-125 (¹²⁵I) implant brachytherapy. The association between urinary symptom flare and prostate-specific antigen (PSA) bounce was investigated.

Methods

Changes in the IPSS and OABSS were prospectively recorded in 355 patients who underwent seed implantation. The percentage distribution of patients according to the difference between the flare peak and post-implant nadir was plotted to define significant increases in the scores. The clinicopathologic characteristics, treatment parameters, and post-implant dosimetric parameters were compared between the non-flare and flare groups. PSA bounce was defined as an elevation of ≥0.1 ng/mL or ≥0.4 ng/mL compared to the previous lowest value, followed by a decrease to a level at or below the pre-bounce value.

Results

A clinically significant increase required an IPSS increase of at least 12 points and an OABSS increase of at least 6 points based on a time-course analysis of total scores and the QOL index. Assessment only by IPSS failed to detect 40 patients (11%) who had urinary symptom flare according to the OABSS. Univariate and multivariate analyses revealed that patients treated with higher biologically effective doses and those without diabetes mellitus had higher risks of urinary flare. There was no statistical correlation between the incidence and time of urinary symptom flare onset and that of a PSA bounce.

Conclusions

To our knowledge, this is the first report to prove the clinical potential of the OABSS as an assessment tool for urinary symptom flare after seed implantation. Our findings showed that persistent lower urinary tract symptoms after seed implantation were attributed to storage rather than to voiding issues. We believe that assessment with the OABSS combined with the IPSS would aid in decision-making in terms of timing, selection of a treatment intervention, and assessment of the outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12894-017-0251-1) contains supplementary material, which is available to authorized users.

Does combination therapy with tamsulosin and trospium chloride improve lower urinary tract symptoms after SEEDS brachytherapy for prostate cancer compared with tamsulosin alone? : A prospective, randomized, controlled trial

OBJECTIVE

To compare the efficacy of combination therapy with an alpha-blocker and an anticholinergic to monotherapy with an alpha blocker on lower urinary tract symptoms (LUTS) following brachytherapy in prostate cancer patients.

MATERIAL AND METHODS

A total of 124 patients that had been clinically diagnosed with localized prostate cancer and underwent prostate brachytherapy were enrolled in the present study. Patients were randomized and allocated to two groups, including 60 to the combination group (tamsulosin 0.2 mg/day and trospium chloride 20 mg twice daily) and 64 to the monotherapy group (tamsulosin 0.2 mg/day). Treatment began 1 day after brachytherapy and continued for 6 months. LUTS were compared between the two groups using the total International Prostate Symptom Score (IPSS), storage and voiding IPSS subscores, quality of life (QoL) scores, maximum flow rate (Qmax), and postvoid residual (PVR) urine volume at 1, 3, 6, and 12 months after implantation.

RESULTS

In all, 111 patients were ultimately analyzed in the study. Compared with pretreatment scores, a significant increase in total IPSS was found at 1, 3, and 6 months in both groups, but no statistically significant differences were observed between the two groups. The combination therapy group showed a greater decrease in the IPSS storage score compared with the monotherapy group at 1, 3, and 6 months (p = 0.031, 0.030 and 0.042, respectively). Patients receiving tamsulosin plus trospium chloride also showed significant improvements in QoL at 1 and 3 months compared with tamsulosin alone (P = 0.039, P = 0.047). Between the two groups, there was no significant difference in IPSS voiding score, Qmax, and PVR from baseline to each point of the study period.

CONCLUSIONS

Combination therapy with tamsulosin and trospium chloride helped to improve IPSS storage symptoms and Qol scores in prostate brachytherapy patients with LUTS compared with tamsulosin monotherapy.

Scientific impact of studies published in temporarily available radiation oncology journals: a citation analysis

The purpose of this study was to review all articles published in two temporarily available radiation oncology journals (Radiation Oncology Investigations, Journal of Radiosurgery) in order to evaluate their scientific impact. From several potential measures of impact and relevance of research, we selected article citation rate because landmark or practice-changing research is likely to be cited frequently. The citation database Scopus was used to analyse number of citations. During the time period 1996-1999 the journal Radiation Oncology Investigations published 205 articles, which achieved a median number of 6 citations (range 0-116). However, the most frequently cited article in the first 4 volumes achieved only 23 citations. The Journal of Radiosurgery published only 31 articles, all in the year 1999, which achieved a median number of 1 citation (range 0-11). No prospective randomized studies or phase I-II collaborative group trials were published in these journals. Apparently, the Journal of Radiosurgery acquired relatively few manuscripts that were interesting and important enough to impact clinical practice. Radiation Oncology Investigations’ citation pattern was better and closer related to that reported in several previous studies focusing on the field of radiation oncology. The vast majority of articles published in temporarily available radiation oncology journals had limited clinical impact and achieved few citations. Highly influential research was unlikely to be submitted during the initial phase of establishing new radiation oncology journals.

Acute urinary morbidity after a permanent 125I implantation for localized prostate cancer

We evaluated the predictive factors of acute urinary morbidity (AUM) after prostate brachytherapy. From November 2005 to January 2007, 62 patients with localized prostate cancer were treated using brachytherapy. The (125)Iodine ((125)I) seed-delivering method was a modified peripheral pattern. The prescribed dose was 144 Gy. Urinary morbidity was scored at 3 months after implantation. The clinical and treatment parameters were analysed for correlation with AUM. In particular, in this study, Du90 (the minimal dose received by 90% of the urethra), Dup90 (the minimal dose received by 90% of the proximal half of the urethra on the bladder side) and Dud90 (the minimal dose received by 90% of the distal half of the urethra on the penile side) were analysed. We found that 43 patients (69.4%) experienced acute urinary symptoms at 3 months after implantation. Of them, 40 patients had Grade 1 AUM, one patient had Grade 2 pain, and two patients had Grade 2 urinary frequency. None of the patients had ≥Grade 3. Univariate and multivariate analysis revealed that Du90 and Dup90 were significantly correlated with AUM. In this study, Du90 and Dup90 were the most significant predictors of AUM after prostate brachytherapy.

Prospective longitudinal comparative study of health-related quality of life and treatment satisfaction in patients treated with hormone therapy, radical retropubic prostatectomy, and high or low dose rate brachytherapy for prostate cancer

PURPOSE

To evaluate the effects of four different prostate cancer treatments on quality of life (QoL) and patient satisfaction.

METHODS

Ninety-six prostate cancer patients were treated with hormone therapy, radical retropubic prostatectomy, high dose rate brachytherapy, or low dose rate brachytherapy. We assessed general, cancer-specific, and prostate disease-specific QoL. More than one year since commencement of treatment, the patients were asked the following questions: 1) How do you feel about your treatment? 2) Would you undergo the same treatment again?

RESULTS

The comparison of baseline and 12-month results showed that general and cancer-specific QoL had changed little in all groups. At baseline, the general and cancer-specific QoL tended to be lower in the hormone therapy patients. In the radical the retropubic prostatectomy patients, all scores on the Medical Outcomes Study 36-Item Short Form were worse than the baseline scores at three months. Scores for the International Index of Erectile Function-5 had also worsened, with no recovery. In the low-dose rate brachytherapy patients, the prostate disease-specific QoL at baseline tended to improve. However, the satisfaction levels for each treatment were reasonably good, and most patients would choose the same treatment again.

CONCLUSIONS

The results of each of the four treatments differed in assessments of QoL. In the radical retropubic prostatectomy patients, the decrease in the International Index of Erectile Function-5 scores was especially remarkable and did not show recovery. In contrast, both brachy therapy groups had attained superior sexual function. However, regardless of the quality of life evaluations, most patients surveyed were satisfied with their treatments and would choose the same treatment again.

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.

Factors influencing urinary symptoms 10 years after permanent prostate seed implantation

PURPOSE

We investigated the factors that influenced urinary symptoms in the first 10 years after prostate brachytherapy.

MATERIALS AND METHODS

A total of 1,932 men were treated with prostate brachytherapy alone or with external beam irradiation and followed a mean of 6.8 years. The influence of pretreatment American Urological Association symptom score (7 or less, 8 to 19, 20 or greater), external beam radiotherapy, (125)I or (103)Pd, biological effective dose, age, prostate size and hormone therapy on the change in American Urological Association symptom score (11,491) was compared.

RESULTS

The mean change from initial score (7.4) was 11.4, 5.5, 3.3, 2.7, 1.5, 1.2, 1, 1, 1, 1, 1.3 and 1.4 points at 3, 6 months and 1 to 10 years, respectively (p <0.001). Factors that resulted in a greater increase in urinary symptoms at year 1 were low pretreatment score (p <0.001), no hormonal therapy (p <0.001), younger age (p = 0.046) and higher biological effective dose (p = 0.025). At 10 years patients with an initial score of 20 or greater had an average decrease of 11 points compared to a decrease of 0.9 for an initial score of 8 to 19 and an increase of 2.7 for an initial score of 7 or less (p <0.001). On linear regression the scores at 1 year were influenced by initial score (p <0.001), biological effective dose (p = 0.022), prostate size (p <0.001) and hormonal therapy (p = 0.009). At 10 years only the pretreatment score remained significant (p <0.001).

CONCLUSIONS

There is minimal change in mean American Urological Association symptom score (1.4 points) 10 years after prostate brachytherapy. Patients presenting with high initial scores have the greatest improvement from baseline. Biological effective dose, external beam radiotherapy, hormonal therapy, isotope, patient age and prostate size do not appear to influence long-term urinary symptoms.

Dose escalation to the dominant intraprostatic lesion defined by sextant biopsy in a permanent prostate I-125 implant: a prospective comparative toxicity analysis

PURPOSE

Using real-time intraoperative inverse-planned permanent seed prostate implant (RTIOP/PSI), multiple core biopsy maps, and three-dimensional ultrasound guidance, we planned a boost volume (BV) within the prostate to which hyperdosage was delivered selectively. The aim of this study was to investigate the potential negative effects of such a procedure.

METHODS AND MATERIALS

Patients treated with RTIOP/PSI for localized prostate cancer with topographic biopsy results received an intraprostatic boost (boost group [BG]). They were compared with patients treated with a standard plan (reference group [RG]). Plans were generated using a simulated annealing inverse planning algorithm. Prospectively recorded urinary, rectal, and sexual toxicities and dosimetric parameters were compared between groups.

RESULTS

The study included 120 patients treated with boost technique who were compared with 70 patients treated with a standard plan. Boost technique did not significantly change the number of seeds (55.1/RG vs. 53.6/BG). The intraoperative prostate V150 was slightly higher in BG (75.2/RG vs. 77.2/BG, p = 0.039). Urethra V100, urethra D90, and rectal D50 were significantly lower in the BG. No significant differences were seen in acute or late urinary, rectal, or sexual toxicities.

CONCLUSIONS

Because there were no differences between the groups in acute and late toxicities, we believe that BV can be planned and delivered to the dominant intraprostatic lesion without increasing toxicity. It is too soon to say whether a boost technique will ultimately increase local control.

Critical discussion of different dose-volume parameters for rectum and urethra in prostate brachytherapy

PURPOSE

To compare different dose-volume histogram (DVH) parameter concepts used for rectum and urethra.

METHODS AND MATERIALS

Thirty-eight postplan CT scans were used to contour the rectum with only one outer contour and as a wall structure. DVH analysis included dose to absolute and relative volumes of both contour types, from RD(0.1cc) to RD(10cc) and from RDmax to RD30, respectively. Volume parameters are reported (RV50-RV300) in cubic centimeters and percentages. The analysis of urethral dose parameters was based on 55 CTs with a urethral catheter. Relative (UD100 to UDmax) and absolute volume parameters (UD(0.5cc) to UD(0.1cc), UV100, UV150) were evaluated, and also correlated to prostate parameters. The analysis was repeated for 10 MRI-based interstitial high-dose rate cases.

RESULTS

The correlation between organ and wall results was high for RD1, RD(2cc), and RD(0.1cc), with differences of <5%. DVH parameters reporting dose to a relative volume (e.g., RD10) or a relative volume related to a certain dose (e.g., RV100 [%]) are sensitive to the number of contoured slices. Dmax has a high uncertainty due to the sampling algorithm. RV100 (145Gy) of 1.5cc is similar to an RD(2cc) of 130Gy. The urethral UD10 and UD(0.1cc) correlate with a mean difference of 1%. The ratios of UD5/UD30, UD10/UD30, and UD5/UD10 were 1.12, 1.09, and 1.03, respectively. The correlation between D90 and D10 for prostate to urethra UD10 was poor.

CONCLUSIONS

Only absolute volume parameters are stable in relation to different contouring concepts. When delineating the outer rectum contour, only RD(2cc) and RD(0.1cc) can be used. RV(100) in cc correlates to RD(2cc). Reporting UD5, UD10, and UD30 together is redundant. Additional information is given when reporting UV100 or UV150.

Comparison between Real-time Intra-operative Ultrasound-based Dosimetry and CT-based Dosimetry for Prostate Brachytherapy Using Cesium-131

The purpose of this study was to evaluate the correlation between real-time intra-operative ultrasound-based dosimetry (USD) and day 0 post-implant CT dosimetry (CTD) 131 Cs permanent prostate brachytherapy. Fifty-two consecutive patients who underwent prostate brachytherapy with 131 Cs were evaluated. Real time operating room planning was performed using VariSeed 7.1 software. Post-needle placement prostate volume was used for real-time planning. Targets for dosimetry were D90 >110%, V100 >90%, V150 <50%, and V200 <20%. The CT scan for post-operative dosimetry was obtained on day 0. The mean values for USD, CTD, and the linear correlation, respectively, were, for D90: 114.0%, 105.61%, and 0.15; for V100: 95.1%, 91.6%, and 0.22; for V150: 51.5%, 46.4%, and 0.40; and for V200: 15.8%, 17.9%, and 0.42. The differences between the mean values for USD and CTD for D90 (p<0.01), V100 (p<0.01), and V150 (p<0.05) were statistically significant. For D90, 30.8% of patients had a >15% difference between USD and CTD and 51.9% of patients had a >10% difference between these values. In contrast, the USD and CTD for V100 were within 5% in 55.8% of patients and within 10% in 86.5% of patients. This study demonstrates a correlation between the mean intra-operative USD and post-implant day 0 CTD values only for V200. Significant variation in D90, V150, and V200 values existed for individual patients between USD and CTD. These results suggest that real-time intra-operative USD does not serve as a surrogate for post-operative CTD, and that post-operative CTD is still necessary.

Secondary effects and biochemical control in patients with early prostate cancer treated with (125)-I seeds

OBJECTIVE

To retrospectively evaluate the toxicity of low-dose-rate brachytherapy and to relate it to the dose-volume to organs at risk.

MATERIAL AND METHODS

We study 160 patients with early prostate cancer, treated with (125)-I implants. Most of them were T1c (63.1%), T2a (35.6%) and Gleason < or =6 (96.2%). Median PSA was 7.2 ng/ml (2.3-13.5); 85.6% were lowrisk cases and 14.4% high-risk cases. Mean follow-up was 24 months (7-48).

RESULTS

Acute urinary toxicity related to urological quality of life (UQL=CVU) was tolerable in 75% and unsatisfactory in 25%. Urinary retention was present in 6.9%. IPSS, V100 and D90 were related to the urinary toxicity grade. Rectal toxicity (RTOG) G2 was 0.6%. Sexual potency showed no changes with regard to the basal in 69%. Actuarial biochemical control was 89.8% at four years.

CONCLUSIONS

Brachytherapy with (125)-I seeds yields acceptable toxicity and excellent biochemical control.

Combined brachytherapy with external beam radiotherapy for localized prostate cancer: reduced morbidity with an intraoperative brachytherapy planning technique and supplemental intensity-modulated radiation therapy

PURPOSE

To report the acute and late treatment-related toxicities of combined permanent interstitial (125)I implantation delivered via real-time intraoperative planning and supplemental intensity-modulated radiotherapy (IMRT) for patients with clinically localized prostate cancer.

METHODS AND MATERIALS

One hundred twenty-seven patients were treated with a combined modality (CM) regimen consisting of (125)I implantation (110Gy) using a transrectal ultrasound-guided approach followed 2 months later by 50.4Gy of IMRT directed to the prostate and seminal vesicles. Late toxicity was scored according to the NCI Common Terminology Criteria for Adverse Events toxicity scale. The acute and late toxicities were compared to a contemporaneously treated cohort of 216 patients treated with (125)I alone to a prescribed dose of 144Gy.

RESULTS

The incidence of Grade 2 acute rectal and urinary side effects was 1% and 10%, respectively, and 2 patients developed Grade 3 acute urinary toxicities. The 4-year incidence of late Grade 2 gastrointestinal toxicity was 9%, and no Grade 3 or 4 complications have been observed. The 4-year incidence of late Grade 2 gastrourinary toxicities was 15% and 1 patient developed a Grade 3 urethral stricture, which was corrected with urethral dilatation. The percentage of patients who experienced resolution of late rectal and urinary symptoms was 92% and 65%, respectively. Multivariate analysis revealed that in addition to higher baseline International Prostate Symptom Score, those patients treated with implant alone compared to CM were more likely to experience Grade 2 acute urinary symptoms. Increased Grade 2 late rectal toxicities were noted for CM patients (9% vs. 1%; p=0.001) as well as a significant increase for late Grade 2 urinary toxicities (15% vs. 9%; p=0.004).

CONCLUSIONS

Adherence to dose constraints with combination real-time brachytherapy using real-time intraoperative planning and IMRT is associated with a low incidence of acute and late toxicities. Acute urinary side effects were significantly less common for CM patients compared to those treated with implantation alone. Late Grade 2 rectal and urinary toxicities were more common for patients treated with CM compared to implant alone.

Comparison of urethral diameters for calculating the urethral dose after permanent prostate brachytherapy

PURPOSE

No studies have yet evaluated the effects of a dosimetric analysis for different urethral volumes. We therefore evaluated the effects of a dosimetric analysis to determine the different urethral volumes.

METHODS

This study was based on computed tomography/magnetic resonance imaging (CT/MRI) combined findings in 30 patients who had undergone prostate brachytherapy. Postimplant CT/MRI scans were performed 30 days after the implant. The urethra was contoured based on its diameter (8, 6, 4, 2, and 0 mm). The total urethral volume-in cubic centimeters [UrV150/200(cc)] and percent (UrV150%/200%), of the urethra receiving 150% or 200% of the prescribed dose-and the doses (UrD90/30/5) in Grays to 90%, 30%, and 5% of the urethral volume were measured based on the urethral diameters.

RESULTS

The UrV150(cc) and UrD30 were statistically different between the of 8-, 6-, 4-, 2-, and 0-mm diameters, whereas the UrD5 was statistically different only between the 8-, 6-, and 4-mm diameters. Especially for UrD5, there was an approximately 40-Gy difference between the mean values for the 8- and 0-mm diameters.

CONCLUSION

We recommend that the urethra should be contoured as a 4- to 6-mm diameter circle or one side of a triangle of 5-7 mm. By standardizing the urethral diameter, the urethral dose will be less affected by the total urethral volume.

Intraoperative real-time planned conformal prostate brachytherapy: Post-implantation dosimetric outcome and clinical implications

PURPOSE

To report the dosimetric outcome of patients with clinically localized prostate cancer treated with I-125 permanent implantation using an intraoperative real-time conformal planning technique.

METHODS AND MATERIALS

Five hundred and sixty-two patients with prostate cancer were treated with I-125 permanent interstitial implantation using a transrectal ultrasound-guided approach. Real-time intraoperative treatment planning software that incorporates inverse planning optimization was used. Dose-volume constraints for this inverse-planning system included: prostate V100 >or=95%, maximal urethral dose <or=120%, and average rectal dose <80% of the prescription dose. Day zero computed tomography scans were acquired for post-implantation dosimetric evaluation.

RESULTS

The median V100 and D90 to the prostate target were 96% and 166 Gy, respectively. In 91% of cases a D90 of >or=140 Gy was achieved. In these patients, the V100 and D90 values did not have a significant influence on PSA relapse-free survival outcomes. The median maximum rectal dose and urethral doses were 104 Gy (72% of the prescription dose) and 187 Gy (130% of the prescription dose). The average and maximum rectal doses exceeding 100% of the prescription dose were less than 1% and 10% of patients, respectively. Average and maximum urethral doses exceeding 150% of the prescription dose were noted in 3% and 24% of patients, respectively. Average and maximum urethral doses exceeded 120% of the prescription dose in 21% and 58% of patients, respectively. Among patients where >or=2.5 cm(3) of the rectum was exposed to the prescription dose, the incidence of late grade 2 toxicity rectal toxicity was 9% compared to 4% for smaller volumes of the rectum exposed to similar doses (p=0.003). No dosimetric parameter in these patients with tight dose confines for the urethra influenced acute or late urinary toxicity.

CONCLUSION

Real-time intraoperative planning was associated with a 90% consistency of achieving the planned intraoperative dose constraints for target coverage and maintaining planned urethral and rectal constraints in a high percentage of implants. Rectal volumes of >or=2.5 cm(3) exposed to the prescription doses were associated with an increased incidence of grade 2 rectal bleeding. Further enhancements in imaging guidance for optimal seed deposition are needed to guarantee optimal dose distribution for all patients. Whether such improvements lead to further reduction in acute and late morbidities associated with therapy requires further study.

Techniques, indications et résultats de la curiethérapie interstitielle par implants permanents dans le cancer localisé de la prostate

Permanent seed brachytherapy as a monotherapy is an appropriate treatment in patients with low risk localized prostate cancer such as intraprostatic cancer, T1-2 stage, PSA less than 10 ng/mL, low tumour volume, well differentiated cancer (Gleason score less than 7), gland size less than 50 mL, no micturition symptoms that could decompensate after implantation. A brachytherapy program needs a specialized multidisciplinary team with the collaboration of urologists, radiotherapists (authorized person to manipulate radioactive elements), and physicists. The 10-year oncologic and morbidity results have been published in the literature and are comparable to those of other standard treatments of localized prostate cancer such as radical prostatectomy and external beam radiation therapy.

Long-Term Urinary, Sexual, and Rectal Morbidity in Patients Treated with Iodine-125 Prostate Brachytherapy Followed Up for a Minimum of 5 Years

OBJECTIVES

To define the long-term morbidity in patients with prostate cancer who underwent iodine-125 brachytherapy.

METHODS

A total of 325 men with localized prostate cancer treated with iodine-125 brachytherapy had a median follow-up of 7 years (range 5 to 15). The American Urological Association symptom score, erectile function status, rectal bleeding incidence, and presence of urinary incontinence were collected prospectively before implantation and every 6 months thereafter. Comparisons were made between the pretreatment and treatment-related factors and their associations with quality-of-life changes. Associations were tested using the Student t, chi-square, and Wilcoxon signed rank tests.

RESULTS

The median prostate volume and maximal dose to 90% of the prostate was 36.6 cm3 and 167 Gy, respectively. Of the 325 men, 15.7% experienced prostate-specific antigen failure and 4% started androgen deprivation therapy. The mean total symptom and bother scores increased from baseline (P <0.001) to 6 months after implantation, steadily decreased, and were unchanged at the last follow-up visit (P = 0.6). There were no significant associations among patient age, race, hormonal therapy use, prostate size, radiation dose, and urinary morbidity. Incontinence occurred in 4 (1.2%) of the 325 patients at the last follow-up visit and was associated with transurethral resection of the prostate (odds ratio 8.8, 95% confidence interval 1.3 to 62, P = 0.008). Before implantation, 77.2% were able to have an erection adequate for intercourse and 50.6% were able to at the last follow-up visit. A significant correlation was found between potency preservation and age (P <0.001). Rectal bleeding occurred in 78 men (24%) 1 to 3 years after implantation. Nine patients (2.8%) complained of minor bleeding beyond 5 years, which was associated with greater radiation doses (P = 0.023).

CONCLUSIONS

The preservation of urinary, sexual, and rectal quality of life is excellent at long follow-up for patients implanted with iodine-125.

Quality of life after brachytherapy or radical prostatectomy for localized prostate cancer: A prospective longitudinal study

OBJECTIVES

To investigate health-related quality of life (HRQOL) in Japanese men with localized prostate cancer who underwent prostate brachytherapy (BT) or retropubic radical prostatectomy (RRP).

METHODS

A total of 70 patients who underwent BT and 67 who underwent RRP were enrolled in our study. The Medical Outcomes Study 36-Item Short Form (SF-36), University of California, Los Angeles, Prostate Cancer Index, and the International Prostate Symptom Score were administered before and 1, 3, 6, and 12 months after treatment. No patients received neoadjuvant or adjuvant therapy.

RESULTS

The RRP group reported significantly lower scores in several domains of the SF-36 at 1 month (P <0.05), but these domains returned to baseline within 6 months. The BT patients reported no significant changes in any of the general HRQOL domains throughout the follow-up period. The RRP group reported a lower posttreatment urinary function score, which reflected leakage, than the BT group. However, the BT patients experienced a significantly delayed recovery of the urinary bother score. The data from the International Prostate Symptom Score showed adverse effects from BT on voiding symptoms for the initial 6 months after treatment. No differences were found in bowel symptoms. RRP was associated with worse sexual function than BT, although nerve-sparing surgery minimized the difference.

CONCLUSIONS

The results of this study have indicated that BT and RRP have meaningfully different profiles in the recovery of general QOL. The differences in the recovery of disease-specific HRQOL were pronounced during the first 12 months after treatment.

Prospective evaluation of quality of life after interstitial brachytherapy for localized prostate cancer

PURPOSE

Permanent interstitial brachytherapy (IB) has become an increasingly appealing therapeutic option for localized prostate cancer (LPC) among physicians and patients because it involves short hospitalization and treatment and its postulated low degree of toxicity may reduce its impact on the patients' quality of life (QoL). The aim of this prospective study was to assess the impact of IB on the QoL of patients with LPC.

METHODS AND MATERIALS

A validated self-completed questionnaire was administered to the patients before and after IB and then at yearly intervals. The items allowed the identification of seven subscales exploring physical well-being (PHY), physical autonomy (POW), psychological well-being (PSY), relational life (REL), urinary function (URI), rectal function (REC), and sexual function (SEX).

RESULTS

The assessment of the QoL of 147 patients treated between May 2000 and February 2005 revealed no relevant differences in the PHY scale scores 1 month after IB or later, and the same was true of the POW, PSY, and REL scales. Urinary function significantly worsened after IB and returned to pretreatment levels only after 3 years; the impact of the treatment on the URI scale was greater in the patients with good baseline urinary function than in those presenting more urinary symptoms before IB. Rectal and sexual functions were significantly worse only at the post-IB evaluation.

CONCLUSIONS

The results of the present study confirm that the impact of IB on the patients' QoL is low despite its transient negative effects on some function, and extend existing knowledge concerning QoL after IB.

Prediction of Urinary Symptoms After 125Iodine Prostate Brachytherapy

AIMS

To evaluate the post-treatment urinary morbidity experienced by a cohort of men undergoing ultrasound-based transperineal prostate brachytherapy, as monotherapy for early stage carcinoma of the prostate.

MATERIALS AND METHODS

One hundred and thirty-four consecutive patients received prostate brachytherapy between March 2000 and July 2002, and were asked to complete the International Prostate Symptom Score (IPSS) and Hospital Anxiety and Depression (HAD) questionnaires before treatment and at 1, 3, 6, 9, 12 and 18 months after implant. Data on catheterisation and surgical interventions were also recorded. Pre-treatment IPSS, dosimetry and other variables were analysed in relation to catheterisation rates and post-treatment IPSS scores at each time window.

RESULTS

One hundred and eleven patients returned sufficient data for meaningful analysis. Of the patients who completed IPSS at 1 month, 85 (97%) reported deterioration in IPSS scores. This peak of symptoms, identified by a rise in median IPSS, started to improve by 3 months, and was approaching baseline by 18 months. The only significant determinants of early urinary toxicity were pre-treatment IPSS, pre-treatment prostate volume and the difficulty of implant. However, prostate volume was not significant beyond 1 month. Twenty-six patients required catheterisation at a median of 10 days after implant. Significant predictors of urinary retention were pre-treatment prostate volume and pre-treatment IPSS. Patients requiring catheterisation continued to have significantly higher IPSS at 18 months than patients who had never required a catheter.

CONCLUSION

Brachytherapy was generally well tolerated, with urinary toxicity in most patients persisting for at least 3-6 months after prostate brachytherapy. Those whose pre-treatment prostate volume and IPSS were high experienced more severe urinary symptoms in the first few months.

A simple technique for determining accurate urethral dosimetry after seed brachytherapy for prostate cancer

PURPOSE

To describe a simple technique to define the anatomically accurate urethral location in the postimplant CT scans, after permanent prostate seed implants, without the discomfort associated with use of a catheter.

METHODS AND MATERIALS

We perform preplanned, preloaded transperineal transrectal ultrasound-guided permanent seed implants for men with low-risk prostate cancer. In postimplant CT scans performed 4 weeks after the procedure we previously used a catheter to identify the urethra. We now use retrograde injection of contrast, followed by the retrograde injection of a mixture of contrast and aerated sterile lubricant jelly to opacify the urethra on our CT scans.

RESULTS

This technique is economical, simple, and more comfortable than the use of a catheter. It reliably allows identification of the urethra for the purposes of deriving dose-volume histogram statistics, for quality control. It provides a reference for more accurate determination of the prostate apex.

CONCLUSIONS

We recommend this technique to those performing prostate seed implants wishing to most accurately determine the precise urethral dose parameters in delayed postimplant CT scans, without the need for the discomfort associated with a urethral catheter.

Selecting patients with pretreatment postvoid residual urine volume less than 100 mL may favorably influence brachytherapy-related urinary morbidity

OBJECTIVES

To evaluate the relationship between pretreatment postvoid residual urine (PVR) less than 100 mL and brachytherapy-related urinary morbidity.

METHODS

A total of 204 patients with a pretreatment PVR measurement underwent permanent prostate brachytherapy with urethral-sparing techniques (100% to 140% minimal peripheral dose) for clinical Stage T1b-T2c (2002 American Joint Committee on Cancer staging system) prostate cancer. The median follow-up was 11.7 months. Evaluation of urinary morbidity consisted of the time to International Prostate Symptom Score (IPSS) resolution, length of catheter dependency, and the need for postimplant surgical intervention. IPSS resolution was defined as a return to within 1 point of the score at baseline. In all patients, an alpha-blocker was initiated before implantation and continued at least until the IPSS returned to baseline. Statistically significant predictors of urinary morbidity were determined using Cox regression analysis of multiple clinical, treatment, and dosimetric parameters.

RESULTS

For the entire cohort, the mean time to IPSS resolution was 2.5 months. The urinary catheter was removed on the day of implantation in 171 patients (83.8%), with no patient remaining catheter dependent for more than 3 days. To date, no patient has required postimplant surgical intervention. On multivariate analysis, pretreatment PVR predicted for clinically irrelevant differences in IPSS resolution and did not influence catheter dependency.

CONCLUSIONS

The selection of patients with a pretreatment PVR of less than 100 mL was associated with rapid IPSS resolution, the absence of prolonged (more than 3 days) catheter dependency, and the elimination of postbrachytherapy surgical intervention for bladder outlet obstruction.

Detailed urethral dosimetry in the evaluation of prostate brachytherapy-related urinary morbidity

PURPOSE

To evaluate the relationship between urinary morbidity after prostate brachytherapy and urethral doses calculated at the base, midprostate, apex, and urogenital diaphragm.

METHODS AND MATERIALS

From February 1998 through July 2002, 186 consecutive patients without a prior history of a transurethral resection underwent monotherapeutic brachytherapy (no supplemental external beam radiation therapy or androgen deprivation therapy) with urethral-sparing techniques (average urethral dose 100%-140% minimum peripheral dose) for clinical T1c-T2b (2002 AJCC) prostate cancer. The median follow-up was 45.5 months. Urinary morbidity was defined by time to International Prostate Symptom Score (IPSS) resolution, maximum increase in IPSS, catheter dependency, and the need for postimplant surgical intervention. An alpha blocker was initiated approximately 2 weeks before implantation and continued at least until the IPSS returned to baseline. Evaluated parameters included overall urethral dose (average and maximum), doses to the base, midprostate, apex, and urogenital diaphragm, patient age, clinical T stage, preimplant IPSS, ultrasound volume, isotope, and D90 and V100/150/200.

RESULTS

Of the 186 patients, 176 (94.6%) had the urinary catheter permanently removed on the day of implantation with only 1 patient requiring a urinary catheter >5 days. No patient had a urethral stricture and only 2 patients (1.1%) required a postbrachytherapy transurethral resection of the prostate (TURP). For the entire cohort, IPSS on average peaked 2 weeks after implantation with a mean and median time to IPSS resolution of 14 and 3 weeks, respectively. For the entire cohort, only isotope predicted for IPSS resolution, while neither overall average prostatic urethra nor segmental urethral dose predicted for IPSS resolution. The maximum postimplant IPSS increase was best predicted by preimplant IPSS and the maximum apical urethral dose.

CONCLUSIONS

With the routine use of prophylactic alpha blockers and strict adherence to urethral-sparing techniques, detailed urethral dosimetry did not substantially improve the ability to predict urinary morbidity. Neither the average dose to the prostatic urethra nor urethral doses stratified into base, midprostate, apex, or urogenital diaphragm segments predicted for IPSS normalization. Radiation doses of 100%-140% minimum peripheral dose are well tolerated by all segments of the prostatic urethra with resultant tumoricidal doses to foci of periurethral cancer.

Prophylactic tamsulosin (Flomax) in patients undergoing prostate 125I brachytherapy for prostate carcinoma: Final report of a double-blind placebo-controlled randomized study

PURPOSE

To evaluate the effectiveness of prophylactic tamsulosin (Flomax) in reducing the urinary symptoms in patients undergoing 125I prostate implantation (PI) for prostate adenocarcinoma.

METHODS AND MATERIALS

This is a single-institution, double-blind, placebo-controlled, randomized trial for patients undergoing PI for prostate adenocarcinoma comparing prophylactic tamsulosin versus placebo. Eligibility criteria included patients not taking tamsulosin or other alpha-blockers treated with PI. The patients were randomly assigned to either tamsulosin (0.8 mg, orally once a day) or matched placebo. All patients started the medication 4 days before PI and continued for 60 days. The American Urologic Association (AUA) symptom index questionnaire was used to assess urinary symptoms. The AUA questionnaire was administered before PI for a baseline score and weekly for 8 weeks after PI. Patients were taken off the study if they developed urinary retention, had intolerable urinary symptoms, or wished to discontinue with the trial.

RESULTS

One hundred twenty-six patients were enrolled in this study from November 2001 to January 2003 (118 were evaluable: 58 in the tamsulosin arm and 60 in the placebo group). Pretreatment and treatment characteristics were comparably matched between the two groups. The urinary retention rate was 17% (10 patients) in the placebo group compared with 10% (6 patients) in the tamsulosin group (p = 0.3161). Eighty-eight percent (14 patients) of those who developed urinary retention experienced it within 2 weeks after the PI. Intolerable urinary symptoms were reported equally (10 patients in each group) with 70% occurring in the first 2 weeks after PI. There was a significant difference in mean AUA score in favor of tamsulosin at Week 5 after PI (p = 0.03).

CONCLUSIONS

Prophylactic tamsulosin (0.8 mg/day) before prostate brachytherapy did not significantly affect urinary retention rates, but had a positive effect on urinary morbidity at Week 5 after PI.

Urinary morbidity and incontinence following transurethral resection of the prostate after brachytherapy

PURPOSE

We analyzed the risk of urinary morbidity and incontinence in patients undergoing transurethral resection of the prostate (TURP) following prostate brachytherapy.

MATERIALS AND METHODS

A total of 2,050 patients underwent transperineal radioactive seed implantation of the prostate with or without external beam radiation therapy for the diagnosis of prostate cancer between June 1990 and February 2004. Of the 2,050 patients 38 (2%) underwent minimal (channel) TURP due to urinary symptoms or retention. Urinary morbidity was recorded prior to implantation and at followup intervals using the International Prostate Symptom Score and quality of life assessment scores. All patients underwent post-implantation computerized tomography based dosimetry at 1 month. The dose to 90% of prostate volume, prostate volume covered by 15% of the prescription dose and dose to 30% or 5 cm of urethral volume were recorded. Of the 38 patients 11 (29%) underwent Pd implantation alone and 12 (32%) received a partial (67%) Pd implant with external beam radiation therapy to a median dose of 45 Gy (range 41.4 to 59.4), while 15 (39%) underwent I implantation alone. Median followup after implantation was 38 months (range 2 to 97).

RESULTS

Seven of the 38 patients (18%) undergoing TURP had urinary incontinence. Median time to TURP was 11 months (range 1 to 73). 25% Of patients who received an implant and external beam radiotherapy had urinary incontinence following TURP compared with 15% who underwent implantation alone (p = 0.26). There was no significant correlation between incontinence risk based on the dose to 90% of prostate volume (p = 0.32), the dose to 30% or 5 cm of urethral volume (p = 0.30) or prostate volume covered by 15% of the prescription dose (p = 0.36). Two of 24 patients (8%) who had underwent 2 years or less after implantation had urinary incontinence compared with 5 of 14 (36%) who underwent TURP greater than 2 years following implantation (p = 0.04).

CONCLUSIONS

Urinary incontinence developed in 18% of patients who underwent TURP following prostate brachytherapy. No significant correlations between radiation dose, preimplant prostate volume or hormonal therapy were identified with regard to this risk. Patients in late retention or with obstructive symptoms (greater than 2 years) following implantation who require TURP are at greater risk for incontinence.

Critical organ dosimetry in permanent seed prostate brachytherapy: Defining the organs at risk

PURPOSE

Although permanent seed prostate brachytherapy is associated with a low risk of serious morbidity, proctitis and prolonged irritative and obstructive urinary symptoms may occur. Data are accumulating to help establish thresholds or guidelines for minimizing toxicity, however, no uniform method of defining and calculating the dose to critical organs currently exists. We set out to examine the existing data and propose a uniform method of reporting such that results from different centers can more easily be compared.

METHODS AND MATERIALS

In preparation for a panel discussion at the American Brachytherapy Society 2004 Annual Meeting, four members with expertise in prostate dosimetry and critical organ assessment performed a literature search and, supplemented with their clinical experience, formulated a proposal for defining and reporting dose in a standardized fashion to the critical organs for permanent seed prostate brachytherapy.

RESULTS

As previously recommended by the American Brachytherapy Society, postimplant dosimetry should be performed on all patients undergoing permanent prostate brachytherapy. The standard imaging for postplan assessment is the CT scan. The interval between seed implantation and postplan assessment should be reported. For rectal and urinary morbidities, the critical organs are considered to be the anterior rectum and the prostatic urethra, respectively. For erectile dysfunction, both the neurovascular bundle and penile bulb have been implicated. The rectum should be contoured on all CT scan slices where radioactive seeds are visible. Both the inner and outer walls should be contoured. The dose should be reported as RV100 and RV150, the volumes in cubic centimeters of the rectal wall receiving 100% and 150% of the prescribed dose, respectively. The urethra should be contoured as a structure on each slice where seeds can be seen. The urethra should be identified by either catheterization or fusion with transrectal ultrasound. The dose should be reported as UrD5 and UrD30, which are, respectively, the dose to 5% and 30% of the urethra in Gray. As well, a UrV150 should be reported, which is the volume in cubic centimeters of the urethra receiving 150% of the prescribed dose. No recommendations can be made at this time for reporting neurovascular bundle or penile bulb doses.

CONCLUSIONS

It is essential that toxicity data be collected and reported in a uniform fashion. Thus, the critical organs for toxicity must be defined and the corresponding dosimetry reported in a standard fashion such that guidelines can be established in the future based on data from a cross-section of centers.

The importance of urethra visualization for preplanned permanent prostate implants

PURPOSE

To assess the potential consequences of using a surrogate urethra on urethral dose estimates in preplanned 125I prostate implants.

METHODS AND MATERIALS

For n=220 patients, the A-P and L-R extents of prostate and urethra contours were measured in transrectal ultrasound images. Treatment plans were then developed for 6 patients, of which 5 had atypical urethral positions. For each patient, three plan variations were made using the visualized and two different surrogate urethra contours.

RESULTS

The urethra typically remains fixed in the L-R direction and extends slightly below midgland, but may veer off-center and can come within 0.5 cm of the posterior surface of the prostate. Use of a surrogate urethra can potentially result in up to 30% of the urethra receiving doses exceeding a planned limit of 1.5 x 145 Gy over a contiguous length of 2.0 cm.

CONCLUSIONS

The urethra should be visualized for preplanning purposes, because unintended urethral doses arising from the use of a surrogate urethra can approach levels associated with late urinary morbidity. Visualization is also essential in the postimplant setting for accurate collection of dose-toxicity data.

PROSPECTIVE OUTCOMES ASSOCIATED WITH MIGRATION FROM PREOPERATIVE TO INTRAOPERATIVE PLANNED BRACHYTHERAPY: A SINGLE CENTER REPORT

PURPOSE

Brachytherapy (BT) for prostate cancer can be performed with either preoperative (PO) or intraoperative (IO) planned dosimetry. Potential benefits of intraoperative include fewer procedures for the patient, cost savings and improved accuracy of seed implantation leading to improved tumor control and urinary side effect profile. We report our experience with transition to IO planned BT after performing more than 600 PO planned implants since 1997.

MATERIALS AND METHODS

From September 2001 to February 2003, 46 consecutive patients with T1-3N0M0 adenocarcinoma of the prostate underwent BT. IO dosimetry was performed in 23 patients, while PO dosimetry was used in 23 immediately before changing to IO. American Urological Association (AUA) symptom index questionnaires were administered preoperatively and postoperatively. All patients underwent postoperative dosimetry by computerized tomography. Total, irritative and obstructive AUA scores were compared in the 2 groups using analysis of covariance. Models were adjusted for pretreatment variables of symptom scores, type of procedure and time since procedure.

RESULTS

Median followup was 47 and 45 days for PO and IO dosimetry, respectively. No differences were observed in seed, needle numbers or prostate size in the 2 groups. Average operative times were higher (47 vs 79 minutes, p <0.01) in the IO group but they decreased to nearly the same levels as PO implants in the first 23 cases so treated. Slopes of operative time over date of procedure differed significantly between methods (p <0.01). Comparing PO to IO dosimetry adjusted estimate of difference was -1.96 for total (95% CI -6.4, 2.5), -0.48 for obstructive (95% CI -3.3, 2.3) and -1.78 for irritative (95% CI -3.9, 0.31) AUA score. These differences were neither statistically nor clinically significant.

CONCLUSIONS

Our experience indicates that intraoperative planned BT is easily implemented in clinical practice as a result of a short learning curve. In addition, the approach is not associated with any changes in early postoperative voiding symptoms and, due to only marginally longer operative times, may have a cost advantage by eliminating the preplanning visit and ultrasound.

Androgen deprivation–induced changes in prostate anatomy predict urinary morbidity after permanent interstitial brachytherapy

PURPOSE

To evaluate the cytoreductive consequences of neoadjuvant androgen deprivation therapy on International Prostate Symptom Score (IPSS) normalization, catheter dependency, and the need for surgical intervention secondary to bladder outlet obstruction after permanent interstitial brachytherapy.

METHODS AND MATERIALS

A total of 116 patients (median follow-up, 30 months) with preandrogen and postandrogen deprivation therapy ultrasound studies and no history of preimplant transurethral resection of the prostate were evaluated. Androgen deprivation-induced changes in prostate volume, transition zone (TZ) volume, and urethral location were correlated with IPSS resolution, catheter dependency, and the need for postimplant surgical intervention. Prostate gland and TZ dimensions and volumes were measured by prolate ellipsoid calculation from the static ultrasound images. The urethral location was determined by identification of a urinary catheter. Additional clinical, treatment, and dosimetric parameters evaluated included patient age, pretreatment prostate-specific antigen, Gleason score, clinical T stage, preimplant IPSS, pre- and postandrogen deprivation ultrasound studies, treatment planning volume, supplemental external beam RT, isotope, total implant activity, Day 0 maximal dose received by 90% of the prostate gland, Day 0 percentage of prostate volume receiving 100%, 150%, and 200% of the prescribed minimal peripheral dose, and urethral dose.

RESULTS

For hormonally manipulated patients, the prostate volume at implantation did not have a statistical influence on the percentage of patients returning to IPSS baseline, the time for IPSS normalization, the incidence of catheter dependency, the catheter-dependency time, or the need for postimplant surgical intervention. However, when compared with the hormone-naive cohort, hormonally manipulated patients were more likely to undergo postimplant surgical intervention (5.2% vs. 0.3%, p = 0.001). Greater androgen deprivation-induced reductions in prostate and TZ volumes, along with movement of the urethra closer to the posterior border of the prostate gland, resulted in a decreased incidence of postimplant urinary morbidity. Using Cox regression analysis, the time to IPSS resolution was best predicted by the percentage of TZ volume reduction. Stepwise linear regression analysis demonstrated that the catheter-dependency time was best predicted by the prehormonal therapy prostate volume, posthormonal therapy TZ volume, and the change in the urethral position; prolonged catheter dependency by the percentage of TZ volume reduction, prehormonal therapy TZ index, and the change in the urethral position; and the need for postimplant surgical intervention by the posthormonal therapy TZ index and the change in the urethral location.

CONCLUSION

After neoadjuvant androgen deprivation therapy for volume reduction, some brachytherapy-related urinary morbidity parameters are highly related to the preandrogen deprivation prostate volume, variants in the TZ volume, and changes in the urethral location.

Correlating the degree of needle trauma during prostate brachytherapy and the development of acute urinary toxicity

PURPOSE

To determine if there is an association between the degree of prostate trauma during prostate brachytherapy and development of acute urinary toxicity.

METHODS AND MATERIALS

In a consecutive prospective cohort of permanent (125)I prostate brachytherapy patients, the number of times each needle was repositioned was tracked, and the dosimetry plans were used to determine the number of times needles within 1 cm of the urethra were manipulated. Additionally, prostate volume, total number of needles, number of needles/prostate volume, and the number of periurethral needle manipulations/prostate volume were determined. The need for catheterization beyond 24 hours and the Radiation Therapy Oncology Group (RTOG) urinary toxicity score at 4 weeks were recorded. The independent samples t test was used to search for a correlation between these parameters and the recorded toxicity scores.

RESULTS

Twenty-eight consecutive implant patients were evaluated in the study. Median (range) values were as follows: prostate volume 35 cc ( range, 15-51 cc), number of needles per patient 32 (range, 21-41), number of needle manipulations per patient 94.5 ( range, 55-147), and number of periurethral needle manipulations 42 (range, 17-65). The only significant association between urinary toxicity and these variables was for the number of periurethral needle manipulations (p = 0.025).

CONCLUSIONS

These data provide evidence that needle prostate trauma during brachytherapy contributes to acute urinary toxicity.

Factors predicting for urinary incontinence after prostate brachytherapy

PURPOSE

To define risk factors that predict for urinary incontinence after (125)I prostate brachytherapy.

METHODS AND MATERIALS

Urinary incontinence after (125)I prostate brachytherapy was evaluated using a patient self-assessment questionnaire based on the NCI Common Toxicity Criteria (version 2). Grade 0 is defined as no incontinence; Grade 1 incontinence occurs with coughing, sneezing, or laughing; Grade 2 is spontaneous incontinence with some control; and Grade 3 is no control. One hundred fifty-three patients received monotherapy (145 Gy) (125)I implants between October 1996 and December 2001, and 112 (75%) responded to our survey. Median follow-up was 47 months (range, 14-74 months). Patient characteristics included a preimplant prostate-specific antigen < or =10, Gleason score < or =6, and stage < or =T2b. CT-based postimplant dosimetry was analyzed approximately 30 days after the procedure, and dose-volume histograms of the prostate and the prostatic urethra were generated based on contoured volumes. Dosimetric parameters evaluated as predictive factors for incontinence included the prostate volume; total activity implanted; number of needles; number of seeds; seed activity; urethral D(5), D(10), D(25), D(50), D(75), and D(90) doses; prostate D(90) doses; and prostate V(100), V(200), and V(300). Clinical parameters evaluated included age, Gleason score, prostate-specific antigen, preimplant International Prostate Symptom Score (I-PSS), and length of follow-up.

RESULTS

Urethral D(10) dose and preimplant I-PSS predicted for urinary incontinence on multivariate analysis (p = 0.002 and p = 0.003, respectively). Twenty-eight patients reported Grade 1 incontinence (26%), and 5 patients reported Grade 2 (5%). Patients with Grade 1 and 2 incontinence were analyzed together, because of the small number of patients who experienced Grade 2. No patients reported Grade 3 incontinence. Mean urethral D(10) was 314 +/- 78 Gy in patients with Grade 0 compared with 394 +/- 147 Gy in patients with Grades 1, 2 incontinence (p = 0.002). The incidence of incontinence doubled as the urethral D(10) dose increased above 450 Gy. Patients with Grade 0 had a mean preimplant I-PSS score of 6.6 +/- 4.5 compared with 10.0 +/- 6.4 for Grades 1, 2 (p = 0.003). A significant increase in the incidence of incontinence was noted when the preimplant I-PSS was greater than 15. No relationship was noted between incontinence and prostate volume, total activity implanted, or the number of needles used (p = 0.83, p = 0.89, p = 0.36, respectively).

CONCLUSION

Urethral D(10) dose and preimplant I-PSS are predictive for patients at higher risk of urinary incontinence. To decrease the risk of this complication, an effort should be made to keep the urethral D(10) dose as close to the prescribed dose as possible, and the preimplant I-PSS should be thoroughly evaluated in an attempt to select patients with scores less than 15.

A Spanner in the works: the use of a new temporary urethral stent to relieve bladder outflow obstruction after prostate brachytherapy

PURPOSE

Assessment of the Spanner, a new temporary urethral stent to relieve bladder outflow obstruction and urinary symptoms after brachytherapy.

METHODS AND MATERIALS

Five patients with unusually severe urinary morbidity after (125)I brachytherapy were recruited. The mean time after implant was 40 days (range 25-90). Spanner intraprostatic stents were introduced using topical anesthetic without complication.

RESULTS

All patients were able to void spontaneously with no post-void residual volume of urine. The flow rates increased in all cases (p=0.03) and the International Prostate Symptom Scores were significantly improved after stent insertion in all patients (p=0.03). All patients experienced some degree of pain or dysuria during stent use.

CONCLUSIONS

Bladder outflow obstruction was effectively treated with the Spanner intraprostatic stent, however pain limited the use of the device in the early post-brachytherapy patient group. Pharmacotherapy, stent design modification, or smaller stent diameter may increase the utility of stents after brachytherapy.

What is the optimal dose for 125I prostate implants? A dose-response analysis of biochemical control, posttreatment prostate biopsies, and long-term urinary symptoms

PURPOSE

To define the optimal dose for 125I prostate implants by correlating post implant CT dosimetry findings with urinary symptoms, biochemical failure, and posttreatment biopsies.

METHODS AND MATERIALS

Patients with T1-T2, Gleason score 2-6 prostate cancer treated with I-125 brachytherapy were analyzed. Group 1 (276 patients) was observed from 18 to 108 months (median, 34 months) and had urinary symptoms prospectively assessed using the International Prostate Symptom Score (IPSS) system. Group 2 (181 patients) observed from 24 to 108 months (median, 44 months) and did not receive hormonal therapy. Implant dose was defined as the D90 (dose delivered to 90% of the prostate on a dose-volume histogram). Patients were analyzed by dose categories: <140 Gy, 140 to <160 Gy, 160 to <180 Gy, and > or =180 Gy. In Group 1, the mean pre- to postimplant IPSS scores were compared in different dose categories by using a matched paired t test. In Group 2, the effect of dose on biochemical control was tested with actuarial methods by using the American Society for Therapeutic Radiology and Oncology definition and on local control with posttreatment biopsies (113 patients).

RESULTS

A comparison of pre- with postimplant IPSS revealed no significant changes in scores in the dose groups <180 Gy except for small changes in urgency and bladder emptying in the dose group <140 Gy. In dose group >180 Gy, mean scores changed from 0.5 to 1.0 (p=0.002) for emptying, 0.76 to 1.29 (p=0.004) for weak stream, 0.24 to 0.51 (p=0.009) for straining, 1.55 to 1.82 (p=0.05) for nocturia, and 6.3 to 8.45 (p=0.0009) for the total score. Freedom from biochemical failure (FFBF) at 5 years was 68% for doses <140 Gy, 97% for 140 to <160 Gy, 98% for 160 to <180 Gy, and 95% for > or =180 Gy (p=0.0025). Overall, patients with doses <140 Gy (median follow-up, 66 months) had an FFBF of 68%, compared with 96% for patients with doses > or =140 Gy (median follow-up, 35 months; p=0.0002). Multivariate analysis found dose to be the most significant factor affecting FFBF. Positive biopsies were found in 23% for doses <140 Gy, 21% for 140 to <160 Gy, 10% for 160 to <180 Gy, and 8% for > or =180 Gy. Overall, biopsies were positive in 22% for doses <160 Gy vs. 9% for > or =160 Gy (p=0.05).

CONCLUSIONS

Optimal 125I prostate implants should deliver a D90 of 140-180 Gy, on the basis of postimplant dosimetry. Doses of <140 Gy are associated with increased biochemical failure, and doses >180 Gy with a small increase in long-term urinary symptoms.

Influence of prostate volume on dosimetry results in real-time 125I seed implantation

PURPOSE

Achieving a minimal dose of 140 Gy to 90% of the prostate (D90) on postimplant dosimetry has been shown to yield improved biochemical control by 125I brachytherapy, and a D90 >180 Gy can be associated with increased long-term toxicity of seed implantation. Significant enlargement of the prostate on postimplant CT compared with the ultrasound (US) volume at implantation (CT/US ratio) has been associated with lower dose results, but other factors predicting for high or low doses are not well established. We determined whether the prostate size at implantation influenced the CT/US ratio results affecting postimplant dosimetry or predicted for D90 values <140 or >180 Gy in patients implanted with 125I in a community hospital setting.

METHODS AND MATERIALS

The dosimetry results from 501 patients from 33 community hospitals were analyzed after full dose 125I implantation. Implant radioactivity was obtained from reference tables relating millicuries to prostate volume (PV). Seeds were placed under real-time US guidance with peripheral weighting in a uniform method for all prostate sizes. CT-based dosimetry was performed 1 month after implantation. Dose-volume histogram parameters were analyzed for volume effects, including D90, the dose to 10% and 30% of the rectal wall, and the dose to 30% of the urethra and bladder. The PV was defined as small (<25 cm3), medium (25 to <40 cm3), or large (> or =40 cm3).

RESULTS

The PV ranged from 9 to 79 cm3 (median 32.7). A D90 > or =140 Gy was achieved in 452 patients (90%). The median D90 was 164 Gy (range 90-230) and increased from 149.5 Gy in small prostates to 164 Gy in medium (p <0.001) and 176 Gy in large (p <0.001) prostates. A D90 <140 Gy occurred in 20% of small vs. 9% of medium and 3% of large prostates (p = 0.003). A D90 >180 Gy occurred in 7% of small and 10% of medium vs. 25% of large glands (p <0.001). The rectal dose increased significantly with an enlarging PV. The bladder and urethral doses increased from the small to medium PVs, although did not increase further in the large glands. The median CT/US ratios showed a significant volume relationship, decreasing with enlarging PVs, but were not associated with a D90 <140 or >140 Gy. The D90 results for <140 Gy and >140 Gy occurred at equal activities per volume.

CONCLUSION

Ninety percent of patients implanted by community-level practitioners using reference tables and real-time US-guided implantation achieved a D90 outcome of > or =140 Gy. Significant differences in dose outcomes <140 Gy and >180 Gy occurred related to PV. Those with prostates <25 cm3 had a 20% frequency of D90 <140 Gy, unrelated to excessive postimplant volume enlargement or insufficient activity per reference table, suggesting that the activity-to-volume recommendations may not allow for much variance in final seed position. Such seed displacement may contribute to lower doses, most commonly in small glands. One may consider increasing the activity implanted in small prostates, because a D90 >180 Gy occurred in only 7% of these cases. Patients with glands >40 cm3 were 25% likely to have a D90 result >180 Gy and were at only 3% risk of a D90 <140 Gy. These patients may benefit from intraoperative dosimetry or a reduction in implant activity.

The effect of hormonal manipulation on urinary function following permanent prostate brachytherapy

PURPOSE

To evaluate the effect of hormonal manipulation on catheter dependency, the resolution of urinary symptomatology, and the need for postbrachytherapy transurethral/transincisional resection (TURP/TUIP).

METHODS AND MATERIALS

Seven hundred sixteen consecutive patients (median follow-up, 29 months) underwent brachytherapy for clinical T1b-T3a (1997 AJCC) prostate cancer from January 1998 through August 2002. Of the evaluated cohort, 400 patients were hormone naïve, 227 received short-course cytoreductive (< or = 6 months) hormonal therapy, and 89 received extended (>6 months) hormonal therapy. An alpha-blocker was initiated prior to implantation and continued at least until the International Prostate Symptom Score (I-PSS) returned to baseline levels. Evaluated parameters included age, T-stage, preimplant I-PSS, ultrasound volume, treatment planning volume, hormonal status, supplemental external beam radiation therapy (XRT), isotope, urethral dose, total implant activity, D90, and V100/150/200. Catheter dependency and the incidence of TURP/TUIP were also evaluated.

RESULTS

Six hundred fifty three patients (91.2%) had the urinary catheter permanently removed on day 0 with 15 patients (2.1%) requiring a catheter beyond 4 days. The I-PSS returned to within 1 point of the antecedent value at a median of 4 months. Sixteen patients (2.2%) underwent postimplant TURP/TUIP. A Cox regression indicated that preimplant I-PSS, supplemental XRT, planning target volume, hormonal therapy, and number of seeds were the strongest predictors for I-PSS resolution. Using all available data, the strongest predictors for I-PSS at 18 months following brachytherapy included variants of I-PSS, isotope, and days of catheter dependency. The maximum I-PSS, planning target volume, and XRT best predicted for prolonged (#10878;4 days) catheter dependency. The need for postimplant TURP/TUIP was most closely associated with days of catheter dependency and the maximum increase in I-PSS. However, when only data available prior to implantation was entered into the model, hormonal therapy predicted for postsurgical intervention.

CONCLUSIONS

In this retrospective evaluation, hormonal manipulation did not statistically impact short-term or prolonged urinary catheter dependency or I-PSS at 18 months, but did influence time to I-PSS normalization and the need for postbrachytherapy surgical intervention.

Comparing PSA outcome after radical prostatectomy or magnetic resonance imaging-guided partial prostatic irradiation in select patients with clinically localized adenocarcinoma of the prostate

OBJECTIVES

To determine whether high-dose radiation delivered to a subvolume of the prostate gland (peripheral zone) using intraoperative magnetic resonance imaging-guided brachytherapy provided comparable 5-year prostate-specific antigen (PSA) control rates to radical prostatectomy (RP) in select patients compared prospectively but in a nonrandomized setting.

METHODS

Between 1997 and 2002, 322 and 196 patients with clinical Stage T1c, PSA less than 10 ng/mL, biopsy Gleason score 3 + 4 or less, and without perineural invasion underwent RP or intraoperative magnetic resonance imaging-guided brachytherapy, respectively, and had a 2-year minimal follow-up. Cox regression multivariable analysis was used to evaluate whether the initial therapy, pretreatment PSA level, biopsy Gleason score, percentage of positive biopsies, or prostate gland volume were predictors of the time to post-therapy PSA failure. PSA failure was estimated using the Kaplan-Meier method and defined using the American Society for Therapeutic Radiology Oncology consensus definition.

RESULTS

Only the percentage of positive prostate biopsies (P(Cox) = 0.02) was a significant predictor of the time to post-treatment PSA failure. However, the distribution of this parameter between RP and brachytherapy-treated patients was not significantly different (P(chi-square) = 0.25). The initial therapy did not predict for the time to post-therapy PSA failure (P(Cox) = 0.18). The 5-year estimate of PSA control was 93% versus 95% (P(log-rank) = 0.16) for the RP and brachytherapy patients, respectively.

CONCLUSIONS

Despite only partial prostatic irradiation using intraoperative magnetic resonance imaging-guided brachytherapy, similar 5-year estimates of PSA control were found for both brachytherapy and RP-managed patients.

Salvage brachytherapy for local recurrence after radical prostatectomy and subsequent external beam radiotherapy

OBJECTIVES

To evaluate the technical feasibility, safety, and efficacy of seed implantation for local recurrence after radical prostatectomy and external beam radiotherapy.

METHODS

Between October 1999 and March 2002, 10 patients with targeted, histologically proven local relapse after surgery and subsequent external beam radiotherapy (only in 8 patients), underwent permanent brachytherapy with palladium-103 and iodine-125 after complete restaging. In all patients, an intraoperative morphovolumetric ultrasound study of the target was performed, with a planning target volume ranging from 5 to 26.7 cm(3). The preimplant prostate-specific antigen values ranged from 1.1 to 6.31 ng/mL.

RESULTS

Postplan dosimetry was performed to determine the percentage of the target volume that received a dose equal to, or greater than, the prescribed dose (range 84.5% to 95.9%) and the dose that was delivered to the 90% of the target volume (range 85.08% to 129.43%). The urinary scores, measured using the International Prostate Symptom Score, had normalized at 3 months. Only 1 patient had worsened incontinence during the first 2 months, with subsequent restoration of the previous situation. The other patients did not have any changes in their previous clinical condition. One patient experienced occasional gross hematuria that had been present after external beam radiotherapy. No rectal complications were reported. After a median follow-up of 20.6 months, 7 patients showed a decreasing or stable prostate-specific antigen level.

CONCLUSIONS

This preliminary experience has demonstrated that seed implantation of a neoplastic local recurrence is technically feasible and safe and allows for accurate dosimetry when the area to be treated can be defined by ultrasonography. Longer follow-up, accurate patient selection, and larger series of patients could help to better define the oncologic outcome.

Brachytherapy for prostate cancer

The use of prostate brachytherapy for the treatment of early-stage, low-grade, low-volume carcinoma of the prostate continues to rise. Given the prolonged natural history of these early lesions, treatment failures may take many years or even a decade or more before becoming clinically evident. It is therefore likely that as the brachytherapy data mature, clinicians will be asked to help manage a potentially large cohort of men who have failed this local therapy--a scenario that will provide a number of unique challenges for the treatment of the disease and the management of the lower urinary tract. This article offers a contemporary review and suggestions with regard to the follow-up of patients who have undergone prostate brachytherapy, including low-dose rate permanent implants and high-dose rate temporary implants for the management of localized prostate cancer. In addition, current controversies in defining biochemical failure following radioactive implantation--including important data regarding the "prostate-specific antigen bounce" phenomenon--are discussed. Finally, a comprehensive review of the management of local recurrence following brachytherapy is offered.