Social media refers to Web-based applications through which users create and exchange user-generated content. Most social media networks are available free of charge to everyone who creates an account. Content is generated and shared in real time with users interacting through computers and mobile devices. These qualities make social media of unique utility to medicine: rapid exchange of ideas across the globe in one minute can impact patient care the next.

Academic medicine is showing increased adoption of social media. Major medical journals (eg, British Medical Journal, The Lancet, New England Journal of Medicine, and the Journal of the American Medical Association) all have a presence on Facebook and Twitter. The peer-reviewed biographic database Scopus prominently displays social media impact in the sidebar of every article and abstract page.¹ Urologists in particular have been quick to adopt social media for academic purposes. Matta and colleagues² reported the dramatic increase in Twitter use at the American Urological Association (AUA) and Canadian Urological Association annual meetings. A combined 29 urologists generated 159 tweets at the 2012 meetings, compared with 268 urologists generating 2765 tweets in 2013. Several urology journals such as European Urology and the BJU International have embraced social media by creating Associate Editor roles for social media and digital media, respectively, and have actively encouraged the growth of social media among their readership. Two recent publications underscore the increasing use of social media in urology. 

Use of Social Media in Urology: Data From the American Urological Association

Loeb S, Bayne CE, Frey C, et al.

BJU Int. 2014;113:993-998.

To better understand the utilization of social media by its members, the AUA emailed a 34-question survey to a random sample of 2000 attending urologists and 2047 resident/fellow members in December 2012. Of the 382 (9.4%) surveys that were completed, 245 (64%) were attending urologists. The majority of members (74%) reported having at least one social media account. Level of training (86% residents/fellows vs 66% for attending physicians) and age (83% of those under 40 years vs 56% over 40 years) were associated with the likelihood of having a social media account.

The most commonly used social media accounts were Facebook (93%), LinkedIn (46%), and Twitter (36%). Members used social media for personal reasons 70% of the time. Only 16% used some social media accounts for personal use and others for business, and even fewer used the same accounts for personal and business (8%) or just business alone (4%).

Members reported privacy on social media as a strong priority. Most residents (89%) and attending physicians (52%) have changed their default privacy settings, most commonly to prevent the public and patients from accessing postings and photos. However, the minority of respondents had actually been contacted by a patient on social media (39% of attending physicians vs 10% of residents/fellows).

To complement the AUA survey as it related to present day social medial trends, the authors used the Symplur Web site (Symplur LLC; www.symplur.com) to examine Twitter usage during the 2013 AUA annual meeting. Specifically, Symplur analyzed the amount of Twitter traffic using the indexing hashtag #AUA13. During the 30 days before and after the meeting, a total of 644 unique contributors generated 5058 Tweets for a total of 9,163,185 impressions (sum of all tweets by participants multiplied by number of followers per participant). For comparison, the authors also examined Symplur analytics using the #EAU13 hashtag for the European Association of Urology (EAU) annual meeting held approximately 2 months earlier in March 2013. During the 60-day period around that meeting, there were a total of 1819 tweets from 246 contributors for 1,686,351 impressions.

Limitations of this study include the low response rate to the survey and the use of Symplur analytics, which may underestimate the amount of Twitter participation in meetings because it only captures active use with the designated hashtag. Nevertheless, this study still represents the largest collection of surveyed data on social media use among urologists to date. The examination of Twitter traffic using the meeting hashtags #AUA13 and #EAU13 confirm the increasing utilization of social media among urologists and will provide a useful benchmark for future research on the topic.

International Urology Journal Club via Twitter: 12-Month Experience

Thangasamy IA, Leveridge M, Davies BJ, et al.

Eur Urol. 2014;66:112-117

In this novel publication, the authors describe the initial experience with an international urology journal club performed monthly on Twitter. The discussion occurs via tweets of 140 or fewer characters and is indexed using the hashtag #urojc. Each month, the journal club features an article from a major peer-reviewed journal. Anyone with an Internet connection can read the #urojc discussion, but participation requires a free Twitter account.

During the first 12 months of the international urology journal club, 189 unique participants from 19 countries and 6 continents contributed to the discussion. The mean number of new participants each month was 14. Overall, participants contributed a mean of 195 tweets generating a mean 130,832 impressions each month. The best tweet each month was awarded a prize.

The monthly #urojc articles heavily favored urologic oncology (seven prostate cancer articles, two bladder cancer articles, and one renal cancer article). Additionally, 1 month featured a urolithiasis article, and another month featured an article on live case demonstrations. Each month, article authors and/or key thought leaders joined the #urojc chat.

The international urology journal club is gaining and sustaining active participation in a global capacity not possible in an offline setting. At the time of writing, the international urology journal club’s Twitter account
(@iurojc) has over 1600 followers. Moreover, February’s #urojc discussion on complications after primary tumor treatment of prostate cancer was recently summarized in Lancet Oncology.³ Indeed, the international urology journal club has pioneered a new approach to journal clubs that is now being replicated in other specialties.

In summary, social media provides a new way for urologists to engage in real-time discussion and disseminate knowledge. Social media use has been exponentially increasing at urological meetings. Twitter in particular is a unique platform for engagement, and the international urology journal club has successfully met every month with participation from attending and trainee urologists around the globe.

References

1. Altmetric for Scopus. Altmetric Web site. http://support.altmetric.com/knowledgebase/articles/83246-altmetric-for-scopus. Accessed April 6, 2014.
2. Matta R, Doiron C, Leveridge MJ. The dramatic rise of social media in urology: trends in twitter use at the American and Canadian Urological Association Annual Meetings in 2012 and 2013. J Urol. 2014;192:494-498.
3. Linton KD, Woo HH. Twitter International Urology Journal Club. Complications of prostate cancer treatment. Lancet Oncol. 2014;15:e150-e151.

Prostate-specific Antigen Velocity Risk Count to Discern Significant From Indolent Prostate Cancer

Dara Lundon, MD,¹ Stacy Loeb, MD, MSc² 

¹Department of Urology, New York University, New York; ²Department of Urology and Population Health, New York University and the Manhattan Veterans Affairs Medical Center, New York, NY

[ Rev Urol.2014;16(3):154-156 doi: 10.3909/riu0624b]

© 2014 MedReviews®, LLC

Prostate-specific antigen (PSA) velocity (PSAV) is the calculation of changes in PSA level over time, and was initially suggested more than a decade ago as a means to distinguish benign prostate enlargement from prostate cancer.¹ Since that time, conflicting data on the value of PSA kinetics have been reported. D’Amico and colleagues showed that PSAV predicts the risk of prostate cancer-specific mortality after treatment,² and the Baltimore Longitudinal Study of Aging (BLSA) demonstrated that a PSAV > 0.35 ng/mL/y more than 10 to 15 years prior to diagnosis predicts the future risk of life-threatening prostate cancer.³ However, other studies have questioned the utility of PSAV in clinical practice.⁴ For example, Wolters and colleagues⁵ reported that PSAV was significantly associated with significant prostate cancer on univariate analysis but was not an independent predictor in the multivariable model.⁵

The clinical utility of PSA kinetics is an extremely important issue for many reasons. First, there is ongoing controversy regarding the over-diagnosis of indolent prostate cancer. Thus, there is a need for screening modalities with greater specificity for clinically significant disease. In addition, many active surveillance programs use PSA kinetics as a trigger for intervention, particularly because noninvasive markers serve as an attractive alternative to repeated prostate biopsies.^6,7

To overcome concerns regarding variability in PSA measurements, Carter and colleagues⁸ proposed a novel mechanism of calculation called PSAV risk count; serial PSA velocities are calculated, and the number of times that they exceed a threshold of 0.4 ng/mL/y are counted to tabulate a score. For example, a PSAV risk count of 2 means that the PSAV exceeded 0.4 ng/mL/y twice in a row; a PSAV risk count of 1 occurs when the PSAV exceeds 0.4 ng/mL/y only once, and the risk count is 0 when none of the PSAVs exceed the 0.4 ng/mL/y threshold value. Using data from the BLSA, Carter and colleagues demonstrated that the PSAV risk count provided additional information regarding the presence of life-threatening prostate cancer compared with a single determination of either PSA or PSAV. This review describes two recent studies on PSAV risk count.

Prostate Specific Antigen Velocity (PSAV) Risk Count Improves the Specificity of Screening for Clinically Significant Prostate Cancer

Loeb S, Metter E, Kan D, et al.

BJU Int. 2012;109;508-514.

The purpose of this study was to determine if PSAV risk count could improve the specificity of PSA screening for prostate cancer and high-grade disease. They used data from a large US prostate cancer screening study, in which PSA and digital rectal examination (DRE) were performed at 6- to 12-month intervals.⁹ Prostate biopsy was recommended for PSA levels > 4 ng/mL (before 1995) or > 2.5 ng/mL (after 1995), and/or suspicious findings on DRE.

Toward this end, 18,214 out of 35,536 men who participated in the prostate cancer screening study had sufficient PSA data as to allow calculation of PSAV risk count. In this screened population, the authors analyzed whether PSA velocity risk count could improve the specificity of PSA screening for overall and high-grade prostate cancer. Specifically, the study examined whether PSAV risk count significantly improved the discrimination of biopsy outcome compared with age and PSA alone. Multivariable models and net reclassification analysis were also reported. 

In the entire study population, a PSAV risk count of 2 was associated with 40% sensitivity, 96% specificity, 40% positive predictive value, and 96% negative predictive value for prostate cancer. On multivariate analysis with age and PSA, a PSAV risk count of 2 was associated with an 8.2-fold increased risk of prostate cancer. To predict any prostate cancer diagnosis, the area under the curve (AUC) for a base model including PSA and age was 0.89, which improved significantly with the addition of PSAV risk count (AUC 0.90; P = .026).

To avoid misclassification of participants who did not undergo a prostate biopsy, and to specifically evaluate the relationship of PSAV risk count to tumor features, subset analysis was performed in 1524 men undergoing initial prostate biopsy. In the biopsy subset, prostate cancer was diagnosed in 25.6%, and the Gleason score was ≥ 7 in 17.7. On multivariate analysis, PSAV risk count (odds ration [OR] 5.4; P = .0002) was more strongly associated with Gleason 8 to 10 prostate cancer than PSA (OR 1.07; P = .29) or age (OR 1.06; P = .07). Receiver operating characteristic analysis for the prediction of Gleason 8 to 10 prostate cancer on biopsy demonstrated that a model with PSA and age was significantly improved by the addition of PSAV risk count (AUC increased from 0.625 to 0.725; P = .031). Net reclassification analysis confirmed that PSAV risk count significantly altered the probability of detecting Gleason score ≥ 7 and ≥ 8 disease on biopsy.

Several stratified analyses were also performed. For example, multivariate models performed after stratification by total PSA (< 2.6, 2.6-4, and > 4 ng/mL) showed that PSAV risk count maintained a significant association with prostate cancer detection in all PSA categories (respective ORs of 4.2, 2.3, and 3.6).To determine the utility of PSAV risk count over a longer interval, a separate analysis was performed, which included 14,024 men with at least four successive PSA measurements. In this subgroup, they determined the association between risk counts ranging from 0 to 3 with prostate cancer detection, in which a risk count of 3 indicated that all three serial PSAV measurements exceeded 0.4 ng/mL/y. A risk count of 3 was found in 15% of men with prostate cancer, compared with 1% without prostate cancer (P < .0001). On multivariate analysis with age and PSA, a risk count of 3 (compared with a risk count of 0-2) was associated with a 7.4- fold increased odds of prostate cancer (95% CI, 5.5-10.0; P < .0001).

In summary, this study demonstrated that men with two successive PSAV measurements > 0.4 ng/mL/y (a risk count = 2), had approximately an eightfold increased risk for prostate cancer, and a fivefold increased risk of very high-grade disease when compared with those with a risk count of 0 or 1, after controlling for age and serum PSA concentration. Limitations to this study include the requirement for multiple serial PSA tests to calculate PSAV risk count, such that 48.8% of screening study participants could not be evaluated. There was a notably higher rate of prostate cancer diagnosis (14.1% vs 6.2%) amongst this excluded group, and similarly it will not be possible to calculate risk count for men presenting to the clinic with a high initial PSA level and limited prior PSA history. Also, the majority of this cohort was white which limits the generalizability of the results. Despite these limitations, this large series showed a robust independent association between PSAV risk count with cancer detection and biopsy Gleason score.

Prostate Specific Antigen Velocity Risk Count Predicts Biopsy Reclassification for Men with Very Low Risk Prostate Cancer

Patel HD, Feng Z, Landis P, et al.

J Urol. 2014;191:629-637

The purpose of this study was to examine, for the first time, whether PSAV risk count could help monitor patients on active surveillance. Specifically, this study examined whether PSAV risk count predicted reclassification of disease on repeat biopsy in the Johns Hopkins active surveillance cohort, and whether it provided incremental prognostic value compared to existing clinical predictors. 

In this program, men are followed by semiannual serum PSA measurements and DRE, as well as annual ≥ 12-core prostate biopsy. Using data from 1995 and 2012, 668 men met all very low-risk criteria (clinical stage T1c disease, PSA density (PSAD) less than 0.15 ng/mL/cc, Gleason score 6 or less, two or fewer biopsy cores with cancer, and 50% or less involvement of any core with cancer).¹⁰ 

In the primary analysis including men with at least 30 months on surveillance, higher PSAV risk count was significantly associated with biopsy progression by Gleason score and/or extent of tumor. The 5-year probability of freedom from disease reclassification on biopsy was 9.7%, 18.7%, and 39.5% for men with a risk count of 0, 1, and 2, respectively (P < .01). 

On multivariable analysis, risk counts of 3 and 2 were associated with significant 4.63-fold and 3.73-fold increased hazard ratios for biopsy progression. Overall, they estimated that 581 (42%) of the surveillance biopsies in the cohort could have been avoided in men with a risk count of 0 or 1. Finally, they showed that the addition of PSAV risk count significantly improved discrimination compared to a base model including age, race, PSAD, and cancer on the first surveillance biopsy. Moreover, PSAV risk count was superior to overall PSAV during follow-up, suggesting that this method of calculation is more suitable for use during active surveillance.

It is important to note that PSAV risk count was less reliable during the initial 2 to 3 years on AS, given the potential for misclassification and limited PSA data, underscoring the importance of surveillance biopsies during this period. However, after this initial period, PSAV risk count had a very high negative predictive value (91.5%) and could potentially reduce the number of serial biopsies.

Finally, 35 men from this population were eventually treated with prostatectomy, of which 68.6% were due to biopsy reclassification. At the time of surgery, Gleason ≥ 7 disease was found in 29.4% with a PSAV risk count ≤ 1, versus 68.8% with a risk count > 1. Only a single patient experienced biochemical progression during follow-up, and this patient had a PSAV risk count of 2.

In summary, PSAV risk count was associated with disease reclassification to unfavorable biopsy characteristics in men with very low risk prostate cancer on active surveillance. PSAV risk count also improved model discrimination. With additional validation of these findings in other surveillance cohorts, PSAV risk count may provide another noninvasive way to monitor patients during active surveillance. This could potentially decrease the frequency of biopsies and their associated risk for complications in the long term. A limitation of this study is that the Johns Hopkins cohort was comprised of selected very low-risk patients, which may limit the generalizability to other programs with different inclusion criteria. 

Discussion

Several differences between these studies by Loeb and Patel and colleagues should be highlighted. These include sample size (18,214 vs 668), type of population (screening study vs active surveillance cohort), and primary objective (detecting overall and high-grade disease vs predicting biopsy reclassification during active surveillance).

Despite these differences, both studies provide a consistent message that PSAV risk count was independently associated with increased risk of unfavourable pathology and clinically significant prostate cancer. Additional prospective studies are warranted to examine the role of PSAV risk count as part of screening and active surveillance paradigms. 

Funding for SL: The research reported in this publication was supported by the National Institutes of Health under Award number K07CA178258. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

References

1. Carter HB, Pearson JD, Metter EJ, et al. Longitudinal evaluation of prostate-specific antigen levels in men with and without prostate disease. JAMA;1992:267:2215-2220.
2. D’Amico AV, Chen MH, Roehl KA, Catalona WJ. Preoperative PSA velocity and the risk of death from prostate cancer after radical prostatectomy. N Engl J Med. 2004;351;125-135.
3. Carter HB, Ferrucci L, Kettermann A, et al. Detection of life-threatening prostate cancer with prostate-specific antigen velocity during a window of curability. J Natl Cancer Inst. 2006;98:1521-1527.
4. Vickers AJ, Savage C, O’Brien MF, Lilja H. Systematic review of pretreatment prostate-specific antigen velocity and doubling time as predictors for prostate cancer. J Clin Oncol. 2009;27:398-403.
5. Wolters T, Roobol MJ, Bangma CH, Schröder FH. Is prostate-specific antigen velocity selective for clinically significant prostate cancer in screening? European Randomized Study of Screening for Prostate Cancer (Rotterdam). Eur Urol. 2009;55: 385-392.
6. Klotz L. Active surveillance with selective delayed intervention for favorable risk prostate cancer. Urol Oncol. 2006;24:46-50. 
7. Soloway MS, Soloway CT, Williams S, et al. Active surveillance; a reasonable management alternative for patients with prostate cancer: the Miami experience. BJU Int. 2008;101:165-169.
8. Carter HB, Kettermann A, Ferrucci L, et al. Prostate-specific antigen velocity risk count assessment: a new concept for detection of life-threatening prostate cancer during window of curability. Urology. 2007;70:685-690.
9. Smith DS, Catalona WJ. Rate of change in serum prostate specific antigen levels as a method for prostate cancer detection. J Urol. 1994;152:1163-1167.
10. Epstein JI, Walsh PC, Carmichael M, Brendler CB. Pathologic and clinical findings to predict tumor extent of nonpalpable (stage T1c) prostate cancer. JAMA. 1994;271:368-374.

Prevalence of Infections Associated With Prostate Biopsy

Meena Davuluri,¹ Stacy Loeb, MD, MsC 

¹Upstate Medical Center, Syracuse, NY; ²Department of Urology and Population Health, New York University and the Manhattan Veterans Affairs Medical Center, New York, NY

[ Rev Urol.2014;16(3):156-157 doi: 10.3909/riu0624c]

© 2014 MedReviews®, LLC

It has been estimated that approximately 1 million transrectal ultrasound (TRUS)-guided prostate biopsies are done in both the United States and Europe each year.¹ Previous studies using administrative claims reported an increase in infection-related hospitalizations after biopsy over time in the United States and Canada.¹ However, these studies had limited data on important factors, such as culture results and the type of prophylaxis received, which might help shed light on potential ways to reduce this problem. Accordingly, several international groups have recently undertaken detailed studies on the prevalence of postbiopsy infections that include data on the type of antimicrobial prophylaxis and resistance patterns. 

Infection Related Hospitalizations After Prostate Biopsy in a Statewide Quality Improvement Collaborative

Womble PR, Dixon MW, Linsell SM, et al.; Michigan Urological Surgery Improvement Collaborative

J Urol. doi: 10.1016/j.juro.2013.12.026. [published online ahead of print December 15, 2013]

The goal of the study was to establish the rate of infection-related hospitalizations after prostate biopsy within the state of Michigan by the Michigan Urological Surgery Improvement Collaborative (MUSIC). This registry prospectively collects a variety of clinical data including detailed information on prostate biopsies. Quality assurance for the data collection is achieved by regular on-site audits of all participating practices. 

For this study, exclusion criteria were individuals who were not a part of MUSIC practices and those practices who had performed fewer than 30 TRUS biopsies. A total of 3911 biopsies were ultimately included. Statistical analysis was used to examine the relationship between the type of antimicrobial prophylaxis and infection-related hospitalizations. 

Consistent with previous studies, they reported a total hospitalization rate of 0.97% following prostate biopsy. Although the hospitalization rates varied between 0% to 4.2% among the various MUSIC practices, this difference was not statistically significant. Of these hospital admissions, 92% were infection related, and 91% of patients with cultures grew Escherichia coli. The remaining cultures grew Pseudomonas species. Overall, fluoroquinolone resistance was found in 79% of patients. The study did not find any statistically significant association between prior prostate biopsy, prebiopsy enema, or prostate size with the risk of infectious complications. 

Overall, 96% of the patients had received a fluoroquinolone as antibiotic prophylaxis. Interestingly, patients given a different type of antibiotic prophylaxis that was not compliant with the American Urological Association guidelines were more significantly likely to have infection-related hospitalizations (P = .0026). The authors discuss the importance of adherence to guidelines as a simple first step, and also to consider local resistance profiles. 

This study was limited by the fact that it only included a group of practices in the state of Michigan. Particularly due to geographic differences in antibiotic resistance, these results may not be generalizable to other locations. Additionally, information regarding the number of cores taken per biopsy and further details regarding hospitalizations (ie, intensive care unit admissions and other downstream issues) may have provided more insight. 

Infective Complications After Prostate Biopsy: Outcome of the Global Prevalence Study of Infections in Urology (GPIU) 2010 and 2011, A Prospective Multinational Multicentre Prostate Biopsy Study

Wagenlehner FM, van Oostrum E, Tenke P, et al. 

Eur Urol. 2013;63:521-527

The Global Prevalence Study of Infections in Urology examined the infective complications after prostate biopsy in 84 centers spanning five continents. The goal was to determine the prevalence of infection, as well as to identify specific risk factors. The investigators used an internet-based platform to collect data on baseline patient characteristics and follow-up data during the 2 weeks after biopsy, including urinary tract infection (UTI), hospital admission, urine cultures, and antibiotic treatment. 

Overall, 702 men were included in the database. The vast majority (97.4%) underwent transrectal biopsy and received fluoroquinolone prophylaxis (90.8%). Postbiopsy follow-up data were available for 521 of the participants; 27 developed a symptomatic UTI (5.2%). Within this group, 16 required hospitalization (3.1%), and 10 of the UTIs were culture-positive. E coli was the isolated organism in 8 of the 10 cultures, and all 8 were resistant to fluoroquinolones. Statistical analysis did not reveal any subgroups at higher risk of developing infection. Parameters assessed included age, prostate size, PSA, history of UTI, preoperative bowel preparation, antibiotic prophylaxis, fluoroquinolone prophylaxis, and repeat biopsy. 

This study is unique as it offers a glimpse at biopsy-related infections across a very broad geographic area. Limitations of this study are rooted in its design. As the authors note, the cross-sectional nature of the study precluded the ability to analyze any changes in infective patterns over time. Furthermore, each site only contributed a median of four evaluable patients per year, and 2-week outcomes were only available in 74.2% of patients. Overall, the small sample size in many subgroups limited the statistical power to evaluate risk factors.

 Both of these studies provide unique epidemiologic data on the prevalence of infections after prostate biopsy. They confirm that postbiopsy, infection-related hospitalizations are, in fact, a serious concern that must be discussed with patients undergoing the procedure. The majority of patients in both the Michigan and global surveys still receive fluoroquinolones as prophylaxis, but increases in resistance may require a shift in the protocol moving forward. Additional studies are necessary to examine the cost effectiveness of alternative options, such as expanded prophylaxis and targeted prophylaxis using rectal swab cultures.

References

1. Loeb S, Carter HB, Brendt SI, et al. Complications after prostate biopsy: data from SEER-Medicine. J Urol. 2011;186:1830-1834.
2. American Urological Association: Best Practice Policy Statement on Urologic Surgery Antimicrobial Prophylaxis (2008). www.auanet.org/education/guidelines/antimicrobial-prophylaxis.cfm. Accessed May 2014. 
3. Nam RK, Saskin R, Lee Y, et al. Increasing hospital admission rates for urological complications after transrectal ultrasound guided prostate biopsy. J Urol. 2013;189(suppl):S12-S17. 
4. Womble PR, Dixon MW, Linsell SM,et al.; Michigan Urological Surgery Improvement Collaborative. Infection related hospitalizations after prostate biopsy in a statewide quality improvement collaborative [published online ahead of print December 15, 2013]. J Urol. doi: 10.1016/j.juro.2013.12.026.
5. Wagenlehner FM, van Oostrum E, Tenke P, et al. Infective complications after prostate biopsy: outcome of the Global Prevalence Study of Infections in Urology (GPIU) 2010 and 2011, a prospective multinational multicentre prostate biopsy study. Eur Urol. 2013;63:521-527.