Prostatic Neoplasms: Loblaw DA

Loblaw DA, Virgo KS, Nam R, Somerfield MR, Ben-Josef E, Mendelson DS, Middleton R, Sharp SA, Smith TJ, Talcott J, Taplin M, Vogelzang NJ, Wade JL, Bennett CL, Scher HI, Anonymous00323. · American Society of Clinical Oncology, Alexandria, VA 22314, USA. · J Clin Oncol. · Pubmed #17404365 No free full text.

Abstract: PURPOSE: To update the 2004 American Society of Clinical Oncology (ASCO) guideline on initial hormonal management of androgen-sensitive, metastatic, recurrent, or progressive prostate cancer (PCa). METHODS: The writing committee based its recommendations on an updated systematic literature review. Recommendations were approved by the Expert Panel, the ASCO Health Services Committee, and the ASCO Board of Directors. RESULTS: Seven randomized controlled trials (four new), one systematic review, one meta-analysis (new), one Markov model, and one delta-method 95% CI procedure for active controlled trials (new) informed the guideline update. RECOMMENDATIONS: Bilateral orchiectomy or luteinizing hormone-releasing hormone agonists are recommended initial androgen-deprivation treatments (ADTs). Nonsteroidal antiandrogen monotherapy merits discussion as an alternative; steroidal antiandrogen monotherapy should not be offered. Combined androgen blockade should be considered. In metastatic or progressive PCa, immediate versus symptom-onset institution of ADT results in a moderate decrease (17%) in relative risk (RR) for PCa-specific mortality, a moderate increase (15%) in RR for non-PCa-specific mortality, and no overall survival advantage. Therefore, the Panel cannot make a strong recommendation for early ADT initiation. Prostate-specific antigen (PSA) kinetics and other metrics allow identification of populations at high risk for PCa-specific and overall mortality. Further studies must be completed to assess whether patients with adverse prognostic factors gain a survival advantage from immediate ADT. For patients electing to wait until symptoms for ADT, regular monitoring visits are indicated. For patients with recurrence, clinical trials should be considered if available. Currently, data are insufficient to support use of intermittent androgen blockade outside clinical trials

Loblaw DA, Mendelson DS, Talcott JA, Virgo KS, Somerfield MR, Ben-Josef E, Middleton R, Porterfield H, Sharp SA, Smith TJ, Taplin ME, Vogelzang NJ, Wade JL, Bennett CL, Scher HI, Anonymous00081. · Cancer Policy and Clinical Affairs, 1900 Duke St, Suite 200, Alexandria, VA 22314, USA. · J Clin Oncol. · Pubmed #15184404 No free full text.

Abstract: PURPOSE: To develop a clinical practice guideline for the management of men with metastatic, recurrent, or progressive carcinoma of the prostate. The focus of this document is on the use, combinations, and timing of various forms of androgen deprivation therapy (ADT) for the palliation of men with androgen-sensitive disease. METHODS: An expert panel and writing committee were formed. The questions to be addressed by the guideline were determined, and a systematic review of the literature was performed, which included a search of online databases, bibliographic review, and consultation with content experts. A priori criteria were used to select studies for analysis and study authors were contacted when necessary. RESULTS: There were 10 randomized controlled trials, six systematic reviews, and one Markov model available to inform the guidelines. CONCLUSION: A full discussion between practitioner and patient should occur to determine which therapy is best for the patient. Bilateral orchiectomy or luteinizing hormone releasing hormone agonists are the recommended initial treatments. Nonsteroidal antiandrogen therapy may be discussed as an alternative, but steroidal antiandrogens should not be offered as monotherapy. Patients willing to accept the increased toxicity of combined androgen blockage for a small benefit in survival should be offered nonsteroidal antiandrogen in addition to castrate therapy. Until data from studies using modern medical diagnostic/biochemical tests and standardized follow-up schedules become available, no specific recommendations can be issued regarding the question of early versus deferred ADT. A discussion about the pros and cons of early versus deferred ADT should occur.

Loblaw DA, Cheung P. · Department of Radiation Oncology, University of Toronto, Sunnybrook and Women's College Health Sciences Centre, Toronto, Ontario, Canada. · Can J Urol. · Pubmed #16526985 No free full text.

Abstract: Within the field of radiation oncology in the last 10 years, there have been two major thematic advances in the understanding and treatment of prostate cancer. Computerized treatment planning and high precision delivery techniques have already revolutionized the treatment of this disease. Three randomized studies have reported improved biochemical disease-free survival rates in patients from low- to high-risk disease with higher radiation doses. When given conformally, the higher doses do not appear to increase severe toxicity. The second important discovery was that prostate cancer reacts differently than other tumors to radiation whereby higher doses of radiation per day ("hypofractionated radiation") seem to be more effective in killing prostate cancer cells. A meta-summary of four reports summarizing 21 studies presented herein produced an alpha/beta ratio of 1.3 Gy. The early experience of two hypofractionated trials in intermediate- and high-risk prostate cancer where the equivalent of > 80 Gy (in 2 Gy per day fractions) delivered in 5-6 weeks is reported. In summary, hypofractionated radiation coupled with high-precision techniques may allow for better prostate cancer control rates, shorter treatment times and less toxicity.

Tang CI, Loblaw DA, Cheung P, Holden L, Morton G, Basran PS, Tirona R, Cardoso M, Pang G, Gardner S, Cesta A. · Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada. · Clin Oncol (R Coll Radiol). · Pubmed #18838256 No free full text.

Abstract: AIMS: Most men with low-risk localised prostate cancer prefer treatments with high control rates and minimal disruption to their lives. Hypofractionating external radiation treatments can theoretically maintain high bioequivalent tumour doses, decrease treatment visits and decrease acute and late toxicities. The aim of this study was to assess the toxicity and feasibility of a hypofractionated accelerated regimen for these patients. MATERIALS AND METHODS: The present study was a phase I/II study in which patients with T1-2b, Gleason < or = 6 and prostate-specific antigen (PSA) < or = 10 ng/ml prostate cancer received 35Gy in five fractions, once a week over 29 days. Treatment was delivered with intensity-modulated radiotherapy on standard linear accelerators, with daily image guidance using gold seed fiducials, and a 4mm clinical target volume to planning target volume margin. RESULTS: As of January 2008, the target accrual of 30 patients had been reached and all had completed treatment and at least 6 months of follow-up. Dose-volume histogram objectives were achievable in all patients. Treatment was very well tolerated with no grade 3 or 4 genitourinary toxicity, gastrointestinal toxicity nor fatigue observed (95% confidence interval 0-12%). As a group, compared with baseline, the following additional grade 2 toxicities were observed: 13% genitourinary, 7% gastrointestinal and 10% fatigue. At 6 months all scores had returned to or improved over baseline. The median PSA before treatment was 6.0 ng/ml. At 6 months, the median PSA was 1.8 ng/ml and 75% had a PSA < or = 3.0 ng/ml. CONCLUSIONS: This novel technique using standard linear accelerators seems feasible and is well tolerated. Further follow-up will be carried out to document late toxicity and efficacy.

Choo R, Pearse M, Danjoux C, Gardner S, Morton G, Szumacher E, Loblaw DA, Cheung P. · Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA. · Int J Radiat Oncol Biol Phys. · Pubmed #18436391 No free full text.

Abstract: PURPOSE: To evaluate the acute and late gastrointestinal (GI) and genitourinary (GU) toxicity of postoperative radiotherapy (RT) after radical prostatectomy (RP). METHODS AND MATERIALS: A total of 78 patients with pT3 or positive surgical margins after RP were treated with RT plus 2 years of androgen suppression, according to a Phase II study. Acute and late GI and GU toxicity was prospectively assessed using the National Cancer Institute's Expanded Common Toxicity Criteria, version 2.0. The incidence of late GI and GU toxicity was estimated using a cumulative incidence method. A Cox proportional regression analysis was performed to evaluate the predictive factors for late toxicity. RESULTS: The median patient age was 61 years at RP. The median interval between RP and postoperative RT was 4.2 months. The median follow-up was 42.4 months. Of the 78 patients, 76 and 74 were available for the acute and late toxicity analysis, respectively. Of these patients, 66%, 29%, and 1% experienced Grade 1, 2, and 3 acute GI or GU toxicity, respectively. The cumulative incidence of Grade 2 or greater and Grade 3 or greater late GI toxicity at 36 months was 8.1% and 0%, respectively. The cumulative incidence of Grade 2 or greater and Grade 3 or greater late GU toxicity at 36 months was 16.4% and 2.7%, respectively. None had Grade 4 or greater late toxicity. The severity of acute GU toxicity (less than Grade 2 vs. Grade 2 or greater) was a significant predictor factor for Grade 2 or greater late GU toxicity after adjusting for pre-existing GU dysfunction. CONCLUSIONS: Postoperative RT was generally well tolerated. Grade 3 or greater late GI or GU toxicity was uncommon.

Lim TS, Cheung PC, Loblaw DA, Morton G, Sixel KE, Pang G, Basran P, Zhang L, Tirona R, Szumacher E, Danjoux C, Choo R, Thomas G. · Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada. · Int J Radiat Oncol Biol Phys. · Pubmed #18355982 No free full text.

Abstract: PURPOSE: To evaluate the acute toxicities of hypofractionated accelerated radiotherapy (RT) using a concomitant intensity-modulated RT boost in conjunction with elective pelvic nodal irradiation for high-risk prostate cancer. METHODS AND MATERIALS: This report focused on 66 patients entered into this prospective Phase I study. The eligible patients had clinically localized prostate cancer with at least one of the following high-risk features (Stage T3, Gleason score >or=8, or prostate-specific antigen level >20 ng/mL). Patients were treated with 45 Gy in 25 fractions to the pelvic lymph nodes using a conventional four-field technique. A concomitant intensity-modulated radiotherapy boost of 22.5 Gy in 25 fractions was delivered to the prostate. Thus, the prostate received 67.5 Gy in 25 fractions within 5 weeks. Next, the patients underwent 3 years of adjuvant androgen ablative therapy. Acute toxicities were assessed using the Common Terminology Criteria for Adverse Events, version 3.0, weekly during treatment and at 3 months after RT. RESULTS: The median patient age was 71 years. The median pretreatment prostate-specific antigen level and Gleason score was 18.7 ng/L and 8, respectively. Grade 1-2 genitourinary and gastrointestinal toxicities were common during RT but most had settled at 3 months after treatment. Only 5 patients had acute Grade 3 genitourinary toxicity, in the form of urinary incontinence (n = 1), urinary frequency/urgency (n = 3), and urinary retention (n = 1). None of the patients developed Grade 3 or greater gastrointestinal or Grade 4 or greater genitourinary toxicity. CONCLUSION: The results of the present study have indicated that hypofractionated accelerated RT with a concomitant intensity-modulated RT boost and pelvic nodal irradiation is feasible with acceptable acute toxicity.

Pearce A, Choo R, Danjoux C, Morton G, Loblaw DA, Szumacher E, Cheung P, Deboer G, Chander S. · Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta, Canada. · Int J Radiat Oncol Biol Phys. · Pubmed #16563657 No free full text.

Abstract: PURPOSE: To examine the effect of salvage radiotherapy (RT) plus 2-year androgen suppression (AS) on quality of life (QOL). METHODS AND MATERIALS: A total of 74 patients with biopsy-proven local recurrence or PSA relapse after radical prostatectomy were treated with salvage RT plus 2-year AS, as per a phase II study. Quality of life was prospectively assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire 30-Item Version 3.0 with the added prostate cancer-specific module at baseline and predefined follow-up visits. RESULTS: Patients experienced a significant increase in bowel dysfunction (23%) by the end of RT (p < 0.0001). This bowel dysfunction improved after RT but remained slightly elevated (5-10%) throughout the 2-year AS period. This extent of residual bowel dysfunction would be considered of minimal clinical importance. A similar, but less pronounced, pattern of change did occur for urinary dysfunction. Erectile function showed no change during RT, but had an abrupt decline (10%) with initiation of AS that was of moderate clinical significance (p < 0.01). None of the other QOL domains demonstrated a persistent, significant change from baseline that would be considered of major clinical significance. CONCLUSION: The combined treatment with salvage RT plus 2-year AS had relatively minor long-term effects on QOL.

Nam RK, Zhang WW, Trachtenberg J, Seth A, Klotz LH, Stanimirovic A, Punnen S, Venkateswaran V, Toi A, Loblaw DA, Sugar L, Siminovitch KA, Narod SA. · Division of Urology, Sunnybrook Research Institute, Department of Radiation Oncology, Sunnybrook Health Sciences, University of Toronto, Toronto, Ontario, Canada. · Clin Cancer Res. · Pubmed #19223501 No free full text.

Abstract: PURPOSE: Several single nucleotide polymorphisms (SNP) have been associated with the risk of prostate cancer. The clinical utility of using SNPs in the early detection of prostate cancer has not been evaluated. EXPERIMENTAL DESIGN: We examined a panel of 25 SNPs from candidate genes and chromosomal regions in 3,004 unselected men who were screened for prostate cancer using serum prostate-specific antigen (PSA) and digital rectal examination. All underwent a prostate biopsy. We evaluated the ability of these SNPs to help predict the presence of prostate cancer at biopsy. RESULTS: Of the 3,004 patients, 1,389 (46.2%) were found to have prostate cancer. Fifteen of the 25 SNPs studied were significantly associated with prostate cancer (P=0.02-7x10(-8)). We selected a combination of 4 SNPs with the best predictive value for further study. After adjusting for other predictive factors, the odds ratio for patients with all four of the variant genotypes compared with men with no variant genotype was 5.1 (95% confidence interval, 1.6-16.5; P=0.006). When incorporated into a nomogram, genotype status contributed more significantly than PSA, family history, ethnicity, urinary symptoms, and digital rectal examination (area under the curve=0.74). The positive predictive value of the PSA test ranged from 42% to 94% depending on the number of variant genotypes carried (P=1x10(-15)). CONCLUSIONS: SNP genotyping can be used in a clinical setting for the early detection of prostate cancer in a nomogram approach and by improving the positive predictive value of the PSA test.

Nam RK, Sugar L, Yang W, Srivastava S, Klotz LH, Yang LY, Stanimirovic A, Encioiu E, Neill M, Loblaw DA, Trachtenberg J, Narod SA, Seth A. · Division of Urology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada. · Br J Cancer. · Pubmed #17971772 links to  free full text

Abstract: The prostate-specific gene, TMPRSS2 is fused with the gene for the transcription factor ERG in a large proportion of human prostate cancers. The prognostic significance of the presence of the TMPRSS2:ERG gene fusion product remains controversial. We examined prostate cancer specimens from 165 patients who underwent surgery for clinically localised prostate cancer between 1998 and 2006. We tested for the presence of TMPRSS2:ERG gene fusion product, using RT-PCR and direct sequencing. We conducted a survival analysis to determine the prognostic significance of the presence of the TMPRSS2:ERG fusion gene on the risk of prostate cancer recurrence, adjusting for the established prognostic factors. We discovered that the fusion gene was expressed within the prostate cancer cells in 81 of 165 (49.1%) patients. Of the 165 patients, 43 (26.1%) developed prostate-specific antigen (PSA) relapse after a mean follow-up of 28 months. The subgroup of patients with the fusion protein had a significantly higher risk of recurrence (58.4% at 5 years) than did patients who lacked the fusion protein (8.1%, P<0.0001). In a multivariable analysis, the presence of gene fusion was the single most important prognostic factor; the adjusted hazard ratio for disease recurrence for patients with the fusion protein was 8.6 (95% CI=3.6-20.6, P<0.0001) compared to patients without the fusion protein. Among prostate cancer patients treated with surgery, the expression of TMPRSS2:ERG fusion gene is a strong prognostic factor and is independent of grade, stage and PSA level.

Nam RK, Zhang WW, Loblaw DA, Klotz LH, Trachtenberg J, Jewett MA, Stanimirovic A, Davies TO, Toi A, Venkateswaran V, Sugar L, Siminovitch KA, Narod SA. · Division of Urology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada. · Prostate Cancer Prostatic Dis. · Pubmed #17876339 No free full text.

Abstract: We conducted a genome-wide association study of 3090 sporadic prostate cancer patients and controls using the Affymetrix 10 000 SNP GeneChip. Initial screening of 40 prostate cancer cases and 40 non-cancer controls revealed 237 SNPs to be associated with prostate cancer (P<0.05). Among these SNPs, 33 were selected for further association analysis of 2069 men who had undergone a cancer-screening prostate biopsy. Results identified five loci as being significantly associated with increased prostate cancer risk in this larger sample (rs 1930293, OR=1.7, P=0.03; rs 717809-2p12, OR=1.3, P=0.03; rs 494770-4q34, OR=1.3, P=0.01; rs 2348763-7p21, OR=1.5, P=0.01; rs 1552895-9p22, OR=1.5, P=0.002). To validate these association data, 61 additional HapMap tagSNPs spanning the latter five loci were genotyped in this subject cohort and an additional 1021 men (total subject number=3090). This analysis revealed tag SNP rs 4568789 (chromosome 1q25) and tag SNP rs 13225697 (chromosome 7p21) to be significantly associated with prostate cancer (P-values 0.009 and 0.008, respectively). Haplotype analysis revealed significant associations of prostate cancer with two allele risk haplotypes on both chromosome 1q25 (adjusted OR of 2.7 for prostate cancer, P=0.0003) and chromosome 7p21 (adjusted OR of 1.3, P=0.0004). As linkage data have identified a putative prostate cancer gene on chromosome 1q25 (HPC1), and microarray data have revealed the ETV1 oncogene to be overexpressed in prostate cancer tissue, it appears that chromosome 1q25 and 7p21 may be sites of gene variants conferring risk for sporadic and inherited forms of prostate cancer.

Nam RK, Toi A, Klotz LH, Trachtenberg J, Jewett MA, Appu S, Loblaw DA, Sugar L, Narod SA, Kattan MW. · Division of Urology, Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada. · J Clin Oncol. · Pubmed #17704405 No free full text.

Abstract: PURPOSE: To construct a clinical nomogram instrument to estimate individual risk for having prostate cancer (PC) for patients undergoing prostate specific antigen (PSA) screening, using all risk factors known for PC. PATIENTS AND METHODS: We conducted a cross-sectional study of 3,108 men who underwent a prostate biopsy, including a subset of 408 volunteers with normal PSA levels. Factors including age, family history of PC (FHPC), ethnicity, urinary symptoms, PSA, free:total PSA ratio, and digital rectal examination (DRE) were incorporated in the model. A nomogram was constructed to assess risk for any and high-grade PC (Gleason score >or= 7). RESULTS: Of the 3,108 men, 1,304 (42.0%) were found to have PC. Among the 408 men with a normal PSA (< 4.0 ng/mL), 99 (24.3%) had PC. All risk factors were important predictors for PC by multivariate analysis (P, .01 to .0001). The area under the curve (AUC) for the nomogram in predicting cancer, which included age, ethnicity, FHPC, urinary symptoms, free:total PSA ratio, PSA, and DRE, was 0.74 (95% CI, 0.71 to 0.81) and 0.77 (95% CI, 0.74 to 0.81) for high-grade cancer. This was significantly greater than the AUC that considered using the conventional screening method of PSA and DRE only (0.62; 95% CI, 0.58 to 0.66 for any cancer; 0.69; 95% CI, 0.65 to 0.73 for high-grade cancer). From receiver operating characteristic analysis, risk factors including age, ethnicity, FHPC, symptoms, and free:total PSA ratio contributed significantly more predictive information than PSA and DRE. CONCLUSION: In a PC screening program, it is important to consider age, family history of PC, ethnicity, urinary voiding symptoms, and free:total PSA ratio, in addition to PSA and DRE.

Cheung P, Sixel K, Morton G, Loblaw DA, Tirona R, Pang G, Choo R, Szumacher E, Deboer G, Pignol JP. · Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada. · Int J Radiat Oncol Biol Phys. · Pubmed #15890583 No free full text.

Abstract: Purpose: The objective of the study was to access toxicities of delivering a hypofractionated intensity-modulated radiotherapy (IMRT) boost with individualized intrafraction planning target volume (PTV) margins and daily online correction for prostate position. Methods and materials: Phase I involved delivering 42 Gy in 21 fractions using three-dimensional conformal radiotherapy, followed by a Phase II IMRT boost of 30 Gy in 10 fractions. Digital fluoroscopy was used to measure respiratory-induced motion of implanted fiducial markers within the prostate. Electronic portal images were taken of fiducial marker positions before and after each fraction of radiotherapy during the first 9 days of treatment to calculate intrafraction motion. A uniform 10-mm PTV margin was used for the first phase of treatment. PTV margins for Phase II were patient-specific and were calculated from the respiratory and intrafraction motion data obtained from Phase I. The IMRT boost was delivered with daily online correction of fiducial marker position. Acute toxicity was measured using National Cancer Institute Common Toxicity Criteria, version 2.0. Results: In 33 patients who had completed treatment, the average PTV margin used during the hypofractionated IMRT boost was 3 mm in the lateral direction, 3 mm in the superior-inferior direction, and 4 mm in the anteroposterior direction. No patients developed acute Grade 3 rectal toxicity. Three patients developed acute Grade 3 urinary frequency and urgency. Conclusions: PTV margins can be reduced significantly with daily online correction of prostate position. Delivering a hypofractionated boost with this high-precision IMRT technique resulted in acceptable acute toxicity.

Lock M, Loblaw DA, Choo R, Imrie K. · Department of Radiation Oncology, University of Toronto, Toronto Sunnybrook Regional Cancer Centre, Toronto, Ontario, Canada. · Can J Urol. · Pubmed #11564276 No free full text.

Abstract: BACKGROUND: PC-SPES is a herbal remedy gaining acceptance amongst prostate cancer patients and health care providers due to credible laboratory and clinical studies. However, PC-SPES has not been assessed in the standard rigorous approval process mandated for conventional agents. OBJECTIVES: To present a case of a patient with prostate cancer who, while using PC-SPES, developed disseminated intravascular coagulation (DIC). A review of the literature was conducted to determine if there is a relationship between PC-SPES and hemorrhagic disorders. Methods: Searches were conducted in MEDLINE (1966-December 2000) and the Cochrane Collaboration's database. RESULTS: There are 116 clinical and laboratory based studies of PC-SPES published to date. There are no randomized controlled trials. Clinical studies have demonstrated a significant reduction in prostate specific antigen (PSA) levels within 6 weeks. Improved quality-of-life, reduction in the volume of tumor deposits and reduction in analgesic use has been demonstrated in hormone refractory patients. Laboratory studies suggest that the beneficial effects of PC-SPES are unrelated to physiologic estrogens. However, PC-SPES has a side-effect profile similar to diethylstilbestrol. There is data demonstrating a <5% risk of thromboembolic events, but this is the first report of DIC. CONCLUSION: The study of PC-SPES is in its infancy. This case may serve as a cautionary note to health care providers and patients regarding herbal remedies. Those using PC-SPES should have an increased level of surveillance for bleeding disorders.

Loblaw DA, Wallner K, Dibiase S, Russell K, Blasko J, Ellis W. · Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Ontario, Canada. · Tech Urol. · Pubmed #10798802 No free full text.

Abstract: PURPOSE: To better define the role of small prostate volume in selecting patients for brachytherapy. MATERIALS AND METHODS: Thirty patients with a transrectal ultrasound (TRUS)-based prostate volumes less than 20 cc were treated at the University of Washington by permanent isotope implantation for prostatic carcinoma. Preimplant TRUS studies were taken at 0.5-cm intervals from the base of the gland to the apex. Planning margins of 1 to 5 mm were added to the prostatic margins, and sources were routinely planned to be placed as much as 5 mm outside of the prostatic margin. The prescription dose was 144 and 115 Gy for full-dose iodine 125 and palladium 103 monotherapy, respectively. For patients receiving supplemental external-beam irradiation, the implant doses were 120 and 90 Gy for 125I and 103Pd, respectively. The morning following the implant, axial computed tomographic (CT) images of the prostate were obtained at 0.5-cm intervals with patients in the supine position. Follow-up ranged from 11 to 28 months (median 21 months). RESULTS: The median coverage of the postimplant prostate volume by the prescription dose was 92%. To calculate the incidence of source migration, the number of sources placed at the time of implant was compared with the number identified on postimplant CT scan. The median number of sources implanted was 84 (range 65-103) compared to an average of 82 identified postoperatively, which is consistent with a source migration rate of two. A median of 31 sources appeared to be outside of the prostatic margins, as identified on postimplant CT scan (range 14-53). Of the 23 patients contacted at the time of this report, one had developed acute postimplant urinary retention that resolved within 2 weeks of implantation. At last follow-up, patient pre- and postimplant AUA scores were not substantially different, with the median AUA score increasing from 7 (range 2-21) to 8 (range 1-27). CONCLUSIONS: Patients with small prostate volumes appear to have acceptable morbidity and target coverage with prostate brachytherapy. Based on the data reported here, we do not believe that a small prostate volume in itself is a contraindication to brachytherapy.