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Objective: To evaluate the impact of staging 68 Ga-PSMA-11 PET imaging on radiotherapy (RT) dose and volumes in patients with prostate cancer., Methods: Forty-five patients (89% high or very high risk by NCCN criteria) who underwent 68 Ga-PSMA-11 PET imaging prior to definitive treatment for prostate cancer between December 2015 and December 2016 were included. Locations of 68 Ga-PSMA-11-avid lesions were compared to Radiation Therapy Oncology Group consensus pelvic nodal volumes (clinical target volume [CTV]); coverage of lesions outside the consensus CTV was considered a major change, while dose-escalation to lesions within the consensus CTV was considered a minor change., Results: All patients had 68 Ga-PSMA-11 PET uptake in the prostate. Twenty-five patients (56%) had N1/M1a disease on 68 Ga-PSMA-11 PET scan, of whom 21 (47%) were previously N0. Six patients (13%) had bone metastases on 68 Ga-PSMA-11 PET scan, of whom 4 had prior negative bone scans. Eight patients (18%) had lymph node metastases outside the consensus CTV. Twelve patients (27%) received a RT boost to nodes within the consensus CTV. Six patients (13%) had limited bone metastases treated with focal RT. Overall PSMA PET imaging resulted in major and/or minor changes to RT plans in 24 patients (53%)., Conclusion: 68 Ga-PSMA-11 PET imaging resulted in RT changes in 53% of patients. Prospective investigation is needed to evaluate the clinical benefit of RT changes based on staging 68 Ga-PSMA-11 PET imaging., (Published by Elsevier Inc.)

The Cancer of the Prostate Strategic Urological Research Endeavor (CaPSURE) is an ongoing longitudinal observational study of current trends in prostate cancer staging and treatment across a spectrum of different treatment facilities in the United States. To date, the study has documented 2 principal findings: (a) a large variation exists in the treatment choices applied to similar patient presentations across the range of facility type, size, and geographic location in the United States; and (b) although it does not seem to make much difference in mortality outcomes which approach--hormonal therapy, radiotherapy, or surgery--is applied to men at low or intermediate risk, a survival benefit exists with surgery for men at high risk., (Copyright © 2011. Published by Elsevier Inc.)

For most of the past 25 years, 1 of the favored approaches to treating prostate cancer has been the suppression of circulating testosterone with luteinizing hormone-releasing hormone (LHRH) agonists. LHRH agonists produce a downregulation of LHRH receptors and an uncoupling of the LHRH signal transduction mechanism. This leads to a marked reduction in the secretion of bioactive hormones stimulating testosterone production and eventual induction of a reversible, but transient and incomplete, state known as "selective medical hypophysectomy." The treatment with LHRH agonists has proved effective in many settings; however, the dosage and timing strategies depend critically on the patient's disease risk and progression. More recent investigations have suggested that a newer, quicker acting, pure gonadotropin-releasing hormone antagonist might be a preferable treatment approach. It remains a fundamental truth, however, that hormonal therapy is both overused and more toxic than generally appreciated. Therefore, a complete understanding of the indications and applications of this approach is essential for the practice of evidence-based medicine., (Copyright © 2011. Published by Elsevier Inc.)

Objectives: We conducted a secondary analysis of the Radiation Therapy Oncology Group protocol 9413 to compare whether the timing of antiandrogen therapy (concomitant versus adjuvant) and testosterone levels influences the incidence of rectal and urinary toxicity in whole pelvic radiotherapy., Methods: We analyzed two of four study arms, in which all patients received radiotherapy to the whole pelvis followed by a boost to the prostate. The two arms differed solely in the timing of the total of 4 months of total androgen deprivation: arm I (320 patients, given concomitantly) and arm III (319 patients, given as adjuvant therapy). The influence of testosterone levels (measured at baseline and yearly thereafter) and its recovery on late rectal and urinary toxicity were modeled by multivariate logistic regression analysis and Fine and Gray's regression models., Results: The occurrence of late rectal toxicity (grade 0-1 versus 2-5, P = 0.16) and late urinary toxicity (grade 0-1 versus 2-5, P = 0.52) was not significantly different statistically between the two arms. The time to testosterone recovery was significantly lower in the adjuvant arm (mean difference of 3.2 months, P = 0.0103). Age and radiation field size are statistically significant risk factors for late urinary toxicity (P = 0.01 and P = 0.02). Baseline testosterone levels, before beginning total androgen deprivation, were a statistically significant predictive factor for late urinary toxicity (P = 0.03)., Conclusions: Older patients and patients with low testosterone levels at baseline are risk factors for late urinary and rectal toxicities, possibly through impaired tissue repair.

Objectives: To describe our experience in developing a technique for implanting fiducial markers (gold markers and electromagnetic transponders) in the prostate by the transrectal approach under ultrasound guidance., Methods: Our technique requires an endocavitary probe (ultrasound transducer) designed for prostate imaging, an ultrasound system with software to visualize the biopsy trajectory on the imaging screen, and a needle guide specifically designed to fit the probe. Critical aspects of the technique include identifying appropriate implantation locations in the gland, correctly orienting the bevel of the implantation needles, ensuring that the bevel is completely within the gland before deploying markers, and achieving adequate spacing of the markers., Results: Since 1999 we have successfully implanted gold markers in 705 patients. Only 1 patient has developed a urinary tract infection requiring additional antibiotic therapy. There have been no instances of severe rectal bleeding or gross hematuria requiring further intervention. Complication rates have been similarly low for electromagnetic transponders implanted in 44 patients., Conclusions: Implantation of fiducial markers is being used to achieve greater accuracy of external beam radiation therapy for prostate cancer. Our experience can serve as a guide to clinicians for performing this increasingly important procedure in an effective and problem-free manner.

Objectives: To evaluate the significance of pretreatment prostate-specific antigen (pPSA) levels as a predictor of overall survival simultaneously with previously established prognostic factors. The pPSA level is a major predictor of treatment failure after radiotherapy and surgery, but to date has not been shown to predict survival., Methods: This analysis was based on data from 927 patients with clinically localized prostate cancer treated with radiotherapy alone between 1987 and 1998. These patients were stratified into four prognostic risk groups, and multivariate analysis was used to determine the independent impact of pPSA level on PSA failure, progression-free survival (death from any cause after PSA failure), and overall survival (death from any cause)., Results: In a multivariate analysis simultaneously considering the prognostic risk group, a pPSA level greater than or equal to 20 ng/mL was associated with a higher risk of PSA failure and worse progression-free and overall survival., Conclusions: The pPSA level is an independent predictor of survival in patients initially treated with radiotherapy alone.

Objectives: To evaluate the effect of the dose to the bulb of the penis on postradiation potency., Methods: Twenty-one patients reporting potency before three-dimensional conformal radiotherapy had the dose delivered to the bulb of the penis evaluated. This was then compared with the patient assessments of post-treatment sexual function to determine whether a dose-volume relationship exists., Results: Among the patients analyzed to date, a strong dose-volume relationship and the likelihood of remaining potent after treatment seems to exist. Patients receiving a dose of less than 40 Gy to 70% of the bulb of the penis appear to have a much greater likelihood of maintaining potency. Patients receiving 70 Gy or more to 70% of the bulb of the penis appear to be at very high risk of experiencing radiation-induced impotence (P = 0.03)., Conclusions: More studies are needed to confirm these observations. If confirmed, these data suggest that by using three-dimensional-based treatment planning and carefully designed treatment fields, the potency of men treated with radiotherapy might be substantially improved.

Objectives: To report the toxicity profile of patients treated with three-dimensional conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) receiving doses of 82 Gy or more to portions of their prostate., Methods: Forty-four patients treated with radiation therapy for prostate cancer between June 1992 and August 1998 at the University of California, San Francisco received a maximal dose within the target volume (Dmax) of 82 Gy or more. Eighteen patients were boosted selectively to a limited portion of their prostate using IMRT, whereas 26 patients were treated with 3D-CRT and had unselected "hot spots" within their prostate. The Radiation Therapy Oncology Group (RTOG) acute and late toxicity scales were used to score gastrointestinal (GI) and genitourinary (GU) morbidity., Results: Median follow-up and Dmax were 23.1 months (range 10.0 to 84.7) and 84.5 Gy (range 82.0 to 96.7), respectively. Of the patients, 59.1% and 34.1% developed some level of acute GU and GI toxicity, respectively. One patient experienced grade 3 acute GI toxicity. No other grade 3 or greater acute toxicity was observed. The 2-year actuarial rates for freedom from late GI and GU morbidity were 77.1% (95% confidence interval [CI] 60.4% to 87.5%) and 79.5% (95% CI 62.7% to 89.3%), respectively. Although no grade 3 or greater late GU morbidity has been observed to date, 3 patients experienced grade 3 late GI morbidity. However, these cases involved rectal bleeding and were effectively managed with laser coagulation/fulguration., Conclusions: Doses of 82 Gy or more to a portion of the prostate gland can be tolerated with acceptable morbidity. This observation supports the continued investigation of IMRT as a means for improving disease control in prostate cancer.

Consecutive patients with abnormal rectal examinations underwent transrectal needle prostate biopsy at VA Medical Center, New Orleans. Each patient was randomized to receive either gentamicin 1.5 mg/kg intravenously (IV) or 500 mg ciprofloxacin (Cipro-Miles) p.o., before and after the biopsy. Serum and prostate tissue levels of ciprofloxacin and gentamicin were measured by high-pressure liquid chromatography and by competitive binding immunoassay, respectively. Blood cultures were obtained, and the patients were observed for twenty-four hours after biopsy. After discharge the patients were followed up by telephone. The incidence of bacteremia and postbiopsy symptoms were less with ciprofloxacin. Prostate tissue levels of this drug were higher than gentamicin, while serum levels were roughly equivalent. Ciprofloxacin is less nephrotoxic, can be given orally, and has a better antimicrobial spectrum. We, therefore, recommend it as prophylaxis against bacteremia in transrectal prostate needle biopsy. Furthermore, it appears that prostatic drug levels are more important than serum levels in preventing bacteremia.