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Bittner N.,Tacoma Valley Radiation Oncology Centers | Merrick G.S.,Wheeling Jesuit University | Galbreath R.W.,Wheeling Jesuit University | Butler W.M.,Wheeling Jesuit University | And 2 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2010

Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores (≤6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and ≤6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy. © 2010 Elsevier Inc. Source


Bittner N.,Tacoma Valley Radiation Oncology Centers | Butler W.M.,Wheeling Jesuit University | Reed J.L.,Wheeling Jesuit University | Murray B.C.,Wheeling Jesuit University | And 3 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2010

Purpose: To evaluate intrafraction prostate displacement among patients immobilized in the prone position using real-time monitoring of implanted radiofrequency transponders. Methods and Materials: The Calypso localization system was used to track prostate motion in patients receiving external beam radiation therapy (XRT) for prostate cancer. All patients were treated in the prone position and immobilized with a thermoplastic immobilization device. Real-time measurement of prostate displacement was recorded for each treatment fraction. These measurements were used to determine the duration and magnitude of displacement along the three directional axes. Results: The calculated centroid of the implanted transponders was offset from the treatment isocenter by ≥2 mm, ≥3 mm, and ≥4 mm for 38.0%, 13.9%, and 4.5% of the time. In the lateral dimension, the centroid was offset from the treatment isocenter by ≥2 mm, ≥3 mm, and ≥4 mm for 2.7%, 0.4%, and 0.06% of the time. In the superior-inferior dimension, the centroid was offset from the treatment isocenter by ≥2 mm, ≥3 mm, and ≥4 mm for 16.1%, 4.7%, and 1.5% of the time, respectively. In the anterior-posterior dimension, the centroid was offset from the treatment isocenter by ≥2 mm, ≥3 mm, and ≥4 mm for 13.4%, 3.0%, and 0.5% of the time. Conclusions: Intrafraction prostate displacement in the prone position is comparable to that in the supine position. For patients with large girth, in whom the supine position may preclude accurate detection of implanted radiofrequency transponders, treatment in the prone position is a suitable alternative. © 2010 Elsevier Inc. All rights reserved. Source


Bittner N.,Tacoma Valley Radiation Oncology Centers | Merrick G.S.,Wheeling Jesuit University | Wallner K.E.,Radiation Oncology | Butler W.M.,Wheeling Jesuit University | And 2 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2010

Purpose: To compare biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) rates among high-risk prostate cancer patients treated with brachytherapy and supplemental external beam radiation (EBRT) using either a mini-pelvis (MP) or a whole-pelvis (WP) field. Methods and Materials: From May 1995 to October 2005, 186 high-risk prostate cancer patients were treated with brachytherapy and EBRT with or without androgen-deprivation therapy (ADT). High-risk prostate cancer was defined as a Gleason score of ≥8 and/or a prostate-specific antigen (PSA) concentration of ≥20 ng/ml. Results: With a median follow-up of 6.7 years, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 91.7% vs. 84.4% (p = 0.126), 95.5% vs. 92.6% (p = 0.515), and 79.5% vs. 67.1% (p = 0.721), respectively. Among those patients who received ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 93.6% vs. 90.1% (p = 0.413), 94.2% vs. 96.0% (p = 0.927), and 73.7% vs. 70.2% (p = 0.030), respectively. Among those patients who did not receive ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 82.4% vs. 75.0% (p = 0.639), 100% vs. 88% (p = 0.198), and 87.5% vs. 58.8% (p = 0.030), respectively. Based on multivariate analysis, none of the evaluated parameters predicted for CSS, while bPFS was best predicted by ADT and percent positive biopsy results. OS was best predicted by age and percent positive biopsy results. Conclusions: For high-risk prostate cancer patients receiving brachytherapy, there is a nonsignificant trend toward improved bPFS, CSS, and OS rates when brachytherapy is given with WPRT. This trend is most apparent among ADT-naïve patients, for whom a significant improvement in OS was observed. © 2010 Elsevier Inc. All rights reserved. Source


Bittner N.,Tacoma Valley Radiation Oncology Centers | Butler W.M.,Wheeling Jesuit University | Kurko B.S.,Wheeling Jesuit University | Merrick G.S.,Wheeling Jesuit University
Practical Radiation Oncology | Year: 2015

To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods and materials: Three Calypso Beacon (Varian Medical Systems, Palo Alto, CA) transponders were implanted into 2 prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data were acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data were acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from the phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was <. 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusions: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible. © 2015 American Society for Radiation Oncology. Source


Bittner N.,Tacoma Valley Radiation Oncology Centers | Merrick G.S.,Wheeling Hospital | Butler W.M.,Wheeling Jesuit University | Bennett A.,Wheeling Jesuit University | Galbreath R.W.,Wheeling Jesuit University
Journal of Urology | Year: 2013

Purpose: We determined the incidence of cancer detection by transperineal template guided mapping biopsy of the prostate in patients with at least 1 previously negative transrectal ultrasound guided biopsy. Materials and Methods: From January 2005 to January 2012 at least 1 negative transrectal ultrasound guided biopsy was done in 485 patients in our clinical database before proceeding with transperineal template guided mapping biopsy. No study patient had a previous prostate cancer diagnosis. The incidence of patients with 1, 2, or 3 or greater previous transrectal ultrasound guided biopsies was 55.3%, 25.9% and 18.8%, respectively. Transperineal template guided mapping biopsy was done in 74.8% of patients for increasing or occasionally persistently increased prostate specific antigen, in 19.4% for atypical small acinar proliferation and in 5.8% for high grade prostatic intraepithelial neoplasia. Results: For the entire study population a median of 59 cores was submitted at transperineal template guided mapping biopsy. Cancer was ultimately detected in 226 patients (46.6%) using the transperineal template guided method, including 196 (86.7%) with clinically significant disease according to the Epstein criteria. The most common cancer detection site on transperineal template guided mapping biopsy was the anterior apex. Conclusions: Transperineal template guided mapping biopsy detected clinically significant prostate cancer in a substantial proportion of patients with negative transrectal ultrasound guided biopsy. This technique should be strongly considered in the context of increasing prostate specific antigen with failed confirmation of the tissue diagnosis. © 2013 American Urological Association Education and Research, Inc. Source

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