Prostatic Neoplasms: Beriwal S

Bice WS, Prestidge BR, Kurtzman SM, Beriwal S, Moran BJ, Patel RR, Rivard MJ, Anonymous00014. · Foundation for Medical Physics Research, San Antonio, TX 78216, USA. · Brachytherapy. · Pubmed #18782682 No free full text.

Abstract: PURPOSE: Published clinical information on the safety and efficacy of (131)Cs implants is limited. We provide consensus recommendations for (131)Cs prostate brachytherapy based on experience to date. METHODS AND MATERIALS: The Cesium Advisory Group (CAG) consists of experienced (131)Cs users. Recommendations are based on three clinical trials, one of which has completed accrual and has been published in the peer reviewed literature, and combined CAG experience of more than 1200 (131)Cs implants. RESULTS: We recommend using 1.059cGyh(-1)U(-1) as the dose rate constant for the IsoRay source. The prescription for monotherapy implants is 115Gy and when combined with 45-50Gy external beam it is 85Gy. Suggested individual source strength ranges from 1.6 to 2.2U. The release criterion for (131)Cs implants is 6mRh(-1) at 1m. (131)Cs brachytherapy should be performed differently from (125)I and (103)Pd brachytherapy: source placement is further from the urethra and rectum; the prostate V(150) should be < or =45%; sufficient margins may be obtained while limiting source placement to the capsule or close to the capsule. The increased dose rate may cause degradation of postimplant quantifiers due to edema. However, large variability in the magnitude and rate of resolution of edema make determination of the most representative postoperative imaging time impossible. The CAG recommends postimplant imaging on the day of the implant. Recommended postimplant evaluation goals include prostate D(90) greater than the prescription dose; maintaining D(u)(,30)<140% of the prescription dose and keeping V(r)(,100)<0.5cm(3). CONCLUSION: It was the consensus of the CAG that optimal (131)Cs implants should be performed differently from those performed with (125)I or (103)Pd. Guidelines have been established to allow for safe and effective delivery of (131)Cs prostate brachytherapy.

Jacobs BL, Gibbons EP, Smith RP, Beriwal S, Komanduri K, Benoit RM. · Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. · Technol Cancer Res Treat. · Pubmed #19044326 No free full text.

Abstract: 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 D(90) >110%, V(100) >90%, V(150) <50%, and V(200) <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 D(90): 114.0%, 105.61%, and 0.15; for V(100): 95.1%, 91.6%, and 0.22; for V(150): 51.5%, 46.4%, and 0.40; and for V(200): 15.8%, 17.9%, and 0.42. The differences between the mean values for USD and CTD for D(90) (p<0.01), V(100) (p<0.01), and V(150) (p<0.05) were statistically significant. For D(90), 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 V(100) 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 V(200). Significant variation in D(90), V(150), and V(200) 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.

Gibbons EP, Smith RP, Beriwal S, Krishna K, Benoit RM. · Department of Urology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA. · Brachytherapy. · Pubmed #18793877 No free full text.

Abstract: PURPOSE: The present study evaluates the postimplant dosimetry when free-hand needles were placed to overcome interference from the pubic arch. METHODS AND MATERIALS: A review of all patients who underwent prostate brachytherapy at our institution from 2001 to 2006 was performed. Postimplant dosimetry in men requiring free-hand needle placement was compared with postimplant dosimetry in men not requiring free-hand needle placement. RESULTS: Of the 145 patients who underwent prostate brachytherapy, 8 patients required free-hand needle placement. The mean prostate volume in the free-hand needle cohort was 46.0cc with a mean of 3.4 free-hand needles placed. In the 137 patients not requiring free-hand needle placement, the mean volume was 39.7cc. The mean D(90), V(100), V(150), and rectal V(100) for the free-hand cohort was 129.5%, 96.3%, 81.6%, and 1.45cc, respectively. The mean D(90), V(100), V(150), and rectal V(100) in men not requiring free-hand needle placement was 126.8%, 97.1%, 78.7%, and 1.03cc, respectively. CONCLUSION: The present study finds that adequate postimplant dosimetry can be obtained if free-hand needles are required due to pubic arch interference.

Williamson R, Smaldone MC, Gibbons EP, Smith RP, Beriwal S, Benoit RM. · Department of Urology, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania 15213, USA. · Urology. · Pubmed #18708241 No free full text.

Abstract: OBJECTIVE: To determine the safety of prostate brachytherapy in patients with clinically localized prostate cancer who have undergone proctocolectomy with ileal pouch-anal anastomosis (IPAA). METHODS: We performed a retrospective chart review of patients with a prior history of IPAA reconstruction who underwent prostate brachytherapy at our institution. Clinical records were reviewed for demographic characteristics, postoperative dosimetry, changes in bowel function, and oncologic outcomes. Data were analyzed using descriptive statistics. RESULTS: Five patients with an IPAA underwent prostate brachytherapy for clinically localized prostate cancer. Mean time from colorectal reconstruction to prostate brachytherapy was 6.3 years. Adequate dosimetry (mean D90 114.9%, mean V100 91.1%, mean R100 0.76 mL) was achieved in each patient. Bowel frequency worsened in the immediate postoperative period in all patients, but all patients returned to their baseline bowel pattern by 4 months after their procedure. Serious complications, such as J-pouch ulcers, fistulas, or fecal incontinence, did not occur in these patients. CONCLUSIONS: Prostate brachytherapy is a safe treatment option in patients with clinically localized prostate cancer and a history of proctocolectomy and IPAA reconstruction.

Smith RP, Beriwal S, Komanduri K, Gibbons E, Benoit R. · Department of Radiation Oncology, University of Pittsburgh Medical Center, St. Maragret's Hospital, 815 Freeport Road, Pittsburgh, PA 15238, USA. · Brachytherapy. · Pubmed #18599357 No free full text.

Abstract: PURPOSE: This study reports on prostate edema after prostate brachytherapy using Cesium-131 ((131)Cs) and describes our method to compensate. METHODS AND MATERIALS: Thirty-one patients underwent brachytherapy using an afterloading technique. Volume measurements of the prostate were taken at various time intervals relative to the date of implant. Real-time operating room dosimetry was used for seed placement on the postneedle prostate volume. The prostate volumes at the various time points were used to determine the effect of prostate edema on dosimetry. RESULTS: Increase in prostate volume occurred immediately after needle placement, as measured by both ultrasound (mean increase of 17.7% (0-75.0%) from 36.8 to 46.9 cc) and Day 0 CT (mean increase of 15.3% (0-54.8%) to 45.9 cc). Day 0 assessment of dosimetry revealed a median D(90) of 102.7% (86.7-133.4%), median V(100) of 91.8% (75.9-98.4%), median V(150) of 44.4% (23.8-81.3%), and median V(200) of 16.3% (7.8-36.9%). This edema dissipated over the next 4 weeks, with resultant changes in dosimetric parameters. By 4 weeks, prostate volume had returned to the preimplant volume (37.7 cc) with increased D(90) (118.2%), V(100) (95.6%), V(150) (63.9%), and V(200) (28.4%). CONCLUSIONS: There is significant immediate edema with prostate brachytherapy. This affects the dosimetry of the implant substantially. Because of this edema, our planning for brachytherapy is done on the postneedle implant volume. Quality assurance studies should be done on the same day as the implant to avoid substantial overestimation of dosimetric parameters.