New nonabsorbable stent versus a microsurgical procedure for vasectomy reversal: evaluating tissue reactions at the anastomosis in rabbits

To investigate whether a newly designed nonabsorbable polymeric stent for the reconstruction of the vas deferens provided less stricturing at the site of the anastomosis in comparison with the conventional microsurgical reconstruction of the vas deferens. Prospective randomized study in 26 rabbits, comparing the one-layer microscopic sutured procedure with a biocompatible stent. University animal laboratory center. Pre- and postoperative average total sperm count, motility, and progressive motile sperm density (PMSD) levels were measured. Histologic sections were taken from the area of the anastomosis, testes, and epididymi after final semen analysis. Rates of stricture and semen parameters. The vas deferens of the rabbits that received a stent showed an inflammatory reaction within the vas wall adjacent to the stent. Transmural histiocytic or eosinophilic reactions were seen in 2/13 (15%) of the stented animals, with atrophy of the epithelium. Histologic cross-sections of the stented vas deferens demonstrated patency. Microscopically sutured rabbits showed more partial obstructions at the site of the anastomosis (5/13 [38%]) with transmural infiltration of lymphocytes and histiocytes. Despite these partial obstructions the vasa were patent. There was a statistically significant difference in favor of the stent with respect to the total sperm count (P=.05). No differences were seen in motility (P=.057) or PMSD (P=.13). The newly developed stent provided patency rates comparable with the conventional one-layer microscopic procedure but showed significantly less stricturing of the anastomose

The use of a newly designed nonabsorbable polymeric stent in reconstructing the vas deferens: a feasibility study in New Zealand white rabbits

OBJECTIVES: To investigate the use of a newly designed stent in the reconstruction of the vas deferens. MATERIALS AND METHODS: In 26 New Zealand White rabbits, 13 conventional one-layer microscopic reconstructions were compared with 13 stented reconstructions of the vas deferens. The newly designed nonabsorbable polymeric stent was shaped to facilitate the rejoining of the two loose ends of the vas deferens, using a central ridge to prevent migration. Semen was collected before and after surgery, using an artificial vaginal system (26 samples before and 115 after surgery). The individual and average total sperm count, motility and progressive motile sperm density (PMSD), were compared after surgery for both groups. After the final semen analysis, rabbits were killed and patency was assessed histologically at the site of the anastomosis. RESULTS: After an initial decline the mean total sperm count increased in both groups. The increase was significantly larger (P = 0.05) in the stented rabbits. The mean motility and PMSD showed no significant differences between both groups (P = 0.11 and 0.71, respectively). Histological examination of the anastomosed area showed partial obstruction (>50% narrowing of the original lumen) in five of the 13 conventionally treated rabbits, with no strictures in the stented group. Despite the narrowing in the conventional group the patency rates were not affected. The mean (range) operating time for the conventional and stented groups was 132 (99-168) and 98 (62-113) min, respectively (P < 0.001). CONCLUSIONS: The total sperm counts, motility and PMSD showed no or little difference after surgery between the conventional and stented rabbits. The stented reconstruction was easy, had no secondary stricturing and reduced the operating tim

A Prospective Multicenter Comparison Study of Risk-adapted Ultrasound-directed and Magnetic Resonance Imaging-directed Diagnostic Pathways for Suspected Prostate Cancer in Biopsy-naive Men

BACKGROUND: European Association of Urology guidelines recommend a risk-adjusted biopsy strategy for early detection of prostate cancer in biopsy-naive men. It remains unclear which strategy is most effective. Therefore, we evaluated two risk assessment pathways commonly used in clinical practice. OBJECTIVE: To compare the diagnostic performance of a risk-based ultrasound (US)-directed pathway (Rotterdam Prostate Cancer Risk Calculator [RPCRC] #3; US volume assessment) and a magnetic resonance imaging (MRI)-directed pathway. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective multicenter study (MR-PROPER) with 1:1 allocation among 21 centers (US arm in 11 centers, MRI arm in ten). Biopsy-naive men with suspicion of prostate cancer (age >/=50 yr, prostate-specific antigen 3.0-50 ng/ml, +/- abnormal digital rectal examination) were included. INTERVENTION: Biopsy-naive men with elevated risk of prostate cancer, determined using RPCRC#3 in the US arm and Prostate Imaging Reporting and Data System scores of 3-5 in the MRI arm, underwent systematic biopsies (US arm) or targeted biopsies (MRI arm). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was the proportion of men with grade group (GG) >/=2 cancer. Secondary outcomes were the proportions of biopsies avoided and GG 1 cancers detected. Categorical (nonparametric) data were assessed using the Mann-Whitney U test and chi(2) tests. RESULTS AND LIMITATIONS: A total of 1965 men were included in the intention-to-treat population (US arm n = 950, MRI arm n = 1015). The US and MRI pathways detected GG >/=2 cancers equally well (235/950, 25% vs 239/1015, 24%; difference 1.2%, 95% confidence interval [CI] -2.6% to 5.0%; p = 0.5). The US pathway detected more GG 1 cancers than the MRI pathway (121/950, 13% vs 84/1015, 8.3%; difference 4.5%, 95% CI 1.8-7.2%; p /=2 cancers were detected in the MRI group than in the US group (52% vs 43%; difference 9.2%, 95% CI 3.0-15%; p /=2 cancers equally well. The risk-adapted US-directed pathway performs well for prostate cancer diagnosis if prostate MRI capacity and expertise are not available. If prostate MRI availability is sufficient, risk assessment should preferably be performed using MRI, as this avoids more biopsies and detects fewer cases of GG 1 cancer. PATIENT SUMMARY: Among men with suspected prostate cancer, relevant cancers were equally well detected by risk-based pathways using either ultrasound or magnetic resonance imaging (MRI) to guide biopsy of the prostate. If prostate MRI availability is sufficient, risk assessment should be performed with MRI to reduce unnecessary biopsies and detect fewer irrelevant cancers

A Prospective Multicenter Comparison Study of Risk-adapted Ultrasound-directed and Magnetic Resonance Imaging–directed Diagnostic Pathways for Suspected Prostate Cancer in Biopsy-naïve Men

Background: European Association of Urology guidelines recommend a risk-adjusted biopsy strategy for early detection of prostate cancer in biopsy-naïve men. It remains unclear which strategy is most effective. Therefore, we evaluated two risk assessment pathways commonly used in clinical practice. Objective: To compare the diagnostic performance of a risk-based ultrasound (US)-directed pathway (Rotterdam Prostate Cancer Risk Calculator [RPCRC] #3; US volume assessment) and a magnetic resonance imaging (MRI)-directed pathway. Design, setting, and participants: This was a prospective multicenter study (MR-PROPER) with 1:1 allocation among 21 centers (US arm in 11 centers, MRI arm in ten). Biopsy-naïve men with suspicion of prostate cancer (age ≥50 yr, prostate-specific antigen 3.0–50 ng/ml, ± abnormal digital rectal examination) were included. Intervention: Biopsy-naïve men with elevated risk of prostate cancer, determined using RPCRC#3 in the US arm and Prostate Imaging Reporting and Data System scores of 3–5 in the MRI arm, underwent systematic biopsies (US arm) or targeted biopsies (MRI arm). Outcome measurements and statistical analysis: The primary outcome was the proportion of men with grade group (GG) ≥2 cancer. Secondary outcomes were the proportions of biopsies avoided and GG 1 cancers detected. Categorical (nonparametric) data were assessed using the Mann-Whitney U test and χ2 tests. Results and limitations: A total of 1965 men were included in the intention-to-treat population (US arm n = 950, MRI arm n = 1015). The US and MRI pathways detected GG ≥2 cancers equally well (235/950, 25% vs 239/1015, 24%; difference 1.2%, 95% confidence interval [CI] −2.6% to 5.0%; p = 0.5). The US pathway detected more GG 1 cancers than the MRI pathway (121/950, 13% vs 84/1015, 8.3%; difference 4.5%, 95% CI 1.8–7.2%; p < 0.01). The US pathway avoided fewer biopsies than the MRI pathway (403/950, 42% vs 559/1015, 55%; difference −13%, 95% CI −17% to −8.3%; p < 0.01). Among men with elevated risk, more GG ≥2 cancers were detected in the MRI group than in the US group (52% vs 43%; difference 9.2%, 95% CI 3.0–15%; p < 0.01). Conclusions: Risk-adapted US-directed and MRI-directed pathways detected GG ≥2 cancers equally well. The risk-adapted US-directed pathway performs well for prostate cancer diagnosis if prostate MRI capacity and expertise are not available. If prostate MRI availability is sufficient, risk assessment should preferably be performed using MRI, as this avoids more biopsies and detects fewer cases of GG 1 cancer. Patient summary: Among men with suspected prostate cancer, relevant cancers were equally well detected by risk-based pathways using either ultrasound or magnetic resonance imaging (MRI) to guide biopsy of the prostate. If prostate MRI availability is sufficient, risk assessment should be performed with MRI to reduce unnecessary biopsies and detect fewer irrelevant cancers

A Prospective Multicenter Comparison Study of Risk-adapted Ultrasound-directed and Magnetic Resonance Imaging-directed Diagnostic Pathways for Suspected Prostate Cancer in Biopsy-naïve Men

BACKGROUND: European Association of Urology guidelines recommend a risk-adjusted biopsy strategy for early detection of prostate cancer in biopsy-naïve men. It remains unclear which strategy is most effective. Therefore, we evaluated two risk assessment pathways commonly used in clinical practice. OBJECTIVE: To compare the diagnostic performance of a risk-based ultrasound (US)-directed pathway (Rotterdam Prostate Cancer Risk Calculator [RPCRC] #3; US volume assessment) and a magnetic resonance imaging (MRI)-directed pathway. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective multicenter study (MR-PROPER) with 1:1 allocation among 21 centers (US arm in 11 centers, MRI arm in ten). Biopsy-naïve men with suspicion of prostate cancer (age ≥50 yr, prostate-specific antigen 3.0-50 ng/ml, ± abnormal digital rectal examination) were included. INTERVENTION: Biopsy-naïve men with elevated risk of prostate cancer, determined using RPCRC#3 in the US arm and Prostate Imaging Reporting and Data System scores of 3-5 in the MRI arm, underwent systematic biopsies (US arm) or targeted biopsies (MRI arm). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was the proportion of men with grade group (GG) ≥2 cancer. Secondary outcomes were the proportions of biopsies avoided and GG 1 cancers detected. Categorical (nonparametric) data were assessed using the Mann-Whitney U test and χ2 tests. RESULTS AND LIMITATIONS: A total of 1965 men were included in the intention-to-treat population (US arm n = 950, MRI arm n = 1015). The US and MRI pathways detected GG ≥2 cancers equally well (235/950, 25% vs 239/1015, 24%; difference 1.2%, 95% confidence interval [CI] -2.6% to 5.0%; p = 0.5). The US pathway detected more GG 1 cancers than the MRI pathway (121/950, 13% vs 84/1015, 8.3%; difference 4.5%, 95% CI 1.8-7.2%; p < 0.01). The US pathway avoided fewer biopsies than the MRI pathway (403/950, 42% vs 559/1015, 55%; difference -13%, 95% CI -17% to -8.3%; p < 0.01). Among men with elevated risk, more GG ≥2 cancers were detected in the MRI group than in the US group (52% vs 43%; difference 9.2%, 95% CI 3.0-15%; p < 0.01). CONCLUSIONS: Risk-adapted US-directed and MRI-directed pathways detected GG ≥2 cancers equally well. The risk-adapted US-directed pathway performs well for prostate cancer diagnosis if prostate MRI capacity and expertise are not available. If prostate MRI availability is sufficient, risk assessment should preferably be performed using MRI, as this avoids more biopsies and detects fewer cases of GG 1 cancer. PATIENT SUMMARY: Among men with suspected prostate cancer, relevant cancers were equally well detected by risk-based pathways using either ultrasound or magnetic resonance imaging (MRI) to guide biopsy of the prostate. If prostate MRI availability is sufficient, risk assessment should be performed with MRI to reduce unnecessary biopsies and detect fewer irrelevant cancers