Active Surveillance for Favorable-Risk Prostate Cancer: A Short Review

Nathan Lawrentschuk,Laurence Klotz 대한비뇨의학회 2010 Investigative and Clinical Urology Vol.51 No.10

Active surveillance is becoming a more widely accepted management strategy in men with low-risk localized prostate cancer. This is in recognition of the knowledge that most men with such cancer are likely to die from other causes. The obvious benefits of active surveillance are reduced morbidity by delaying or avoiding radical gland therapy. These advantages should be balanced against appropriate selection criteria and triggers for moving to radical therapy while on active surveillance. The optimal method by which to identify the small number of men who will progress by use of clinical, biopsy, and imaging data is yet to be defined. Nevertheless, active surveillance is an appealing management option in selected men with prostate cancer and represents a solution to the significant problem of the overdiagnosis of clinically insignificant disease that accompanies prostate-specific antigen (PSA) screening.

Realistic Anatomical Prostate Models for Surgical Skills Workshops Using Ballistic Gelatin for Nerve-Sparing Radical Prostatectomy and Fruit for Simple Prostatectomy

Nathan Lawrentschuk,Uri Lindner,Laurence Klotz 대한비뇨의학회 2011 Investigative and Clinical Urology Vol.52 No.2

Purpose: Understanding of prostate anatomy has evolved as techniques have been refined and improved for radical prostatectomy (RP), particularly regarding the importance of the neurovascular bundles for erectile function. The objectives of this study were to develop inexpensive and simple but anatomically accurate prostate models not involving human or animal elements to teach the terminology and practical aspects of nerve-sparing RP and simple prostatectomy (SP). Materials and Methods: The RP model used a Foley catheter with ballistics gelatin in the balloon and mesh fabric (neurovascular bundles) and balloons (prostatic fascial layers) on either side for the practice of inter- and intrafascial techniques. The SP model required only a ripe clementine, for which the skin represented compressed normal prostate, the pulp represented benign tissue, and the pith mimicked fibrous adhesions. A modification with a balloon through the fruit center acted as a “urethra.”Results: Both models were easily created and successfully represented the principles of anatomical nerve-sparing RP and SP. Both models were tested in workshops by urologists and residents of differing levels with positive feedback. Conclusions: Low-fidelity models for prostate anatomy demonstration and surgical practice are feasible. They are inexpensive and simple to construct. Importantly, these models can be used for education on the practical aspects of nerve-sparing RP and SP. The models will require further validation as educational and competency tools, but as we move to an era in which human donors and animal experiments become less ethical and more difficult to complete, so too will low-fidelity models become more attractive.

Effects of Partial Nephrectomy on Postoperative Blood Pressure

Nathan Lawrentschuk,Greg Trottier,Karli Mayo,Ricardo A Rendon 대한비뇨의학회 2012 Investigative and Clinical Urology Vol.53 No.3

Purpose: The effects of partial nephrectomy (PN) on postoperative blood pressure (BP) are not known, and PN has the potential to worsen BP. We therefore sought to determine whether PN alters postoperative BP. Materials and Methods: Patients who underwent PN for suspected malignancy at our institution from 2002 to 2008 were included. Data on BP and medication from before and after PN were retrieved from family physicians. BP and number of antihypertensive medications were compared after surgery with preoperative values by use of paired t tests and Chi-squared analyses, respectively. Results: Of 74 patients undergoing PN and providing consent, 48 met the inclusion and exclusion criteria, with a median follow-up of 24 months. For the early postoperative period (1 month to 1 year after surgery), the mean BPs (132.3/77.0 mmHg) were unchanged compared with preoperative values (132.4/78.0 mmHg; p=0.59 systolic BP and p=0.30 diastolic BP). For the later postoperative period (beyond 1 year after surgery), the mean postoperative systolic BP was unchanged from the mean preoperative systolic BP (131.2 mmHg vs. 132.4 mmHg, respectively; p>0.30). However, the corresponding average diastolic BP was lower in the long term (78.0 mmHg versus 76.4 mmHg respectively; p=0.01). No significant difference in the mean number of BP medications prescribed preoperatively, at one year, and beyond one year was identified (p>0.37). Conclusions: PN does not result in initial or long-term postoperative deterioration in BP. Purpose: The effects of partial nephrectomy (PN) on postoperative blood pressure (BP) are not known, and PN has the potential to worsen BP. We therefore sought to determine whether PN alters postoperative BP. Materials and Methods: Patients who underwent PN for suspected malignancy at our institution from 2002 to 2008 were included. Data on BP and medication from before and after PN were retrieved from family physicians. BP and number of antihypertensive medications were compared after surgery with preoperative values by use of paired t tests and Chi-squared analyses, respectively. Results: Of 74 patients undergoing PN and providing consent, 48 met the inclusion and exclusion criteria, with a median follow-up of 24 months. For the early postoperative period (1 month to 1 year after surgery), the mean BPs (132.3/77.0 mmHg) were unchanged compared with preoperative values (132.4/78.0 mmHg; p=0.59 systolic BP and p=0.30 diastolic BP). For the later postoperative period (beyond 1 year after surgery), the mean postoperative systolic BP was unchanged from the mean preoperative systolic BP (131.2 mmHg vs. 132.4 mmHg, respectively; p>0.30). However, the corresponding average diastolic BP was lower in the long term (78.0 mmHg versus 76.4 mmHg respectively; p=0.01). No significant difference in the mean number of BP medications prescribed preoperatively, at one year, and beyond one year was identified (p>0.37). Conclusions: PN does not result in initial or long-term postoperative deterioration in BP.

Spermatocytic Seminoma With Sarcoma: An Indication for Adjuvant Chemotherapy in Localized Disease

David Wetherell,Nathan Lawrentschuk,Dennis Gyomber 대한비뇨의학회 2013 Investigative and Clinical Urology Vol.54 No.12

Spermatocytic seminoma (SCS) with sarcoma is an extremely rare testicular tumor with only 11 cases previously described in the literature. We present the 12th case of SCS with sarcoma in a 29-year-old male. SCS itself is an uncommon germ cell tumor with a relatively indolent clinical course that mostly affects males around the fifth decade of life. Sarcomatous differentiation of SCS occurs in 5% to 6% of cases and correlates with a higher possibility of metastatic disease and a poor prognosis. Clinically, this tumor manifests as a slow-growing testicular mass often with an accelerated period of secondary growth. After a concise review of the literature, we conclude that SCS with sarcoma should be treated by radical inguinal orchidectomy with strong consideration given to adjuvant chemotherapy.

Prevention of sepsis prior to prostate biopsy

Liam Toner,Damien M Bolton,Nathan Lawrentschuk 대한비뇨의학회 2016 Investigative and Clinical Urology Vol.57 No.2

Purpose: Urosepsis is the most feared complication of transrectal prostate biopsy. The incidence may be increasing from <1% to 2%–3% in contemporary series. Historically, fluoroquinolones have been effective antibiotic prophylaxis to prevent infective complications but antibiotic resistance is increasing. The increase in antibiotic resistance may contribute to reported increases in urosepsis and hospitalization after transrectal biopsy. This article will review other methods clinicians may employ to reduce the incidence of infective complications after prostate biopsy. Materials and Methods: A systematic review of the literature was conducted using literature databases PubMed and Ovid MEDLINE in August 2015 in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) criteria. Results: Effective strategies to reduce infective complications after transrectal prostate biopsy include augmented prophylaxis with other antibiotics, rectal swab culture directed antibiotic prophylaxis or a transperineal biopsy approach. Needle disinfection, minimizing the number of biopsy needles and rectal disinfectants may also be of use. These methods may be of particular utility in patients with risk factors for developing urosepsis such as recent antibiotic use and overseas travel. Conclusions: The scientific literature describes various techniques designed to reduce infective complications caused by prostate biopsy. Clinicians should consider incorporating these novel techniques into their contemporary practice.

Vancomycin resistant enterococci in urine cultures: Antibiotic susceptibility trends over a decade at a tertiary hospital in the United Kingdom

Liam Toner,Nathan Papa,Sani H. Aliyu,Harveer Dev,Nathan Lawrentschuk,Samih Al-Hayek 대한비뇨의학회 2016 Investigative and Clinical Urology Vol.57 No.2

Purpose: Enterococci are a common cause of urinary tract infection and vancomycin-resistant strains are more difficult to treat. The purpose of this surveillance program was to assess the prevalence of and determine the risk factors for vancomycin resistance in adults among urinary isolates of Enterococcus sp. and to detail the antibiotic susceptibility profile, which can be used to guide empirical treatment. Materials and Methods: From 2005 to 2014 we retrospectively reviewed 5,528 positive Enterococcus sp. urine cultures recorded in a computerized laboratory results database at a tertiary teaching hospital in Cambridge, United Kingdom. Results: Of these cultures, 542 (9.8%) were vancomycin resistant. No longitudinal trend was observed in the proportion of vancomycin-resistant strains over the course of the study. We observed emerging resistance to nitrofurantoin with rates climbing from near zero to 40%. Ampicillin resistance fluctuated between 50% and 90%. Low resistance was observed for linezolid and quinupristin/dalfopristin. Female sex and inpatient status were identified as risk factors for vancomycin resistance. Conclusions: The incidence of vancomycin resistance among urinary isolates was stable over the last decade. Although resistance to nitrofurantoin has increased, it still serves as an appropriate first choice in uncomplicated urinary tract infection caused by vancomycin-resistant Enterococcus sp.

National nephrectomy registries: Reviewing the need for population-based data

John Pearson,Timothy Williamson,Joseph Ischia,Damien M Bolton,Mark Frydenberg,Nathan Lawrentschuk 대한비뇨의학회 2015 Investigative and Clinical Urology Vol.56 No.9

Nephrectomy is the cornerstone therapy for renal cell carcinoma (RCC) and continued refinement of the procedure through research may enhance patient outcomes. A national nephrectomy registry may provide the key information needed to assess the procedure at a national level. The aim of this study was to review nephrectomy data available at a population-based level in Australia and to benchmark these data against data from the rest of the world as an examination of the national nephrectomy registry model. A PubMed search identified records pertaining to RCC nephrectomy in Australia. A similar search identified records relating to established nephrectomy registries internationally and other surgical registries of clinical importance. These records were reviewed to address the stated aims of this article. Population-based data within Australia for nephrectomy were lacking. Key issues identified were the difficulty in benchmarking outcomes and no ongoing monitoring of trends. The care centralization debate, which questions whether small-volume centers provide comparable outcomes to high-volume centers, is ongoing. Patterns of adherence and the effectiveness of existing protocols are uncertain. A review of established international registries demonstrated that the registry model can effectively address issues comparable to those identified in the Australian literature. A national nephrectomy registry could address deficiencies identified in a given nation's nephrectomy field. The model is supported by evidence from international examples and will provide the population-based data needed for studies. Scope exists for possible integration with other registries to develop a more encompassing urological or surgical registry. Need remains for further exploration of the feasibility and practicalities of initiating such a registry including a minimum data set, outcome indicators, and auditing of data.

The use of tissue fiducial markers in improving the accuracy of post-prostatectomy radiotherapy

Chao, Michael,Ho, Huong,Joon, Daryl Lim,Chan, Yee,Spencer, Sandra,Ng, Michael,Wasiak, Jason,Lawrentschuk, Nathan,McMillan, Kevin,Sengupta, Shomik,Tan, Alwin,Koufogiannis, George,Cokelek, Margaret,Foro The Korean Society for Radiation Oncology 2019 Radiation Oncology Journal Vol.37 No.1

Purpose: The aim of this retrospective study was to investigate the use of a radiopaque tissue fiducial marker (TFM) in the treatment of prostate cancer patients who undergo post-prostatectomy radiotherapy (PPRT). TFM safety, its role and benefit in quantifying the set-up uncertainties in patients undergoing PPRT image-guided radiotherapy were assessed. Materials and Methods: A total of 45 consecutive PPRT patients underwent transperineal implantation of TFM at the level of vesicourethral anastomosis in the retrovesical tissue prior to intensity-modulated radiotherapy. Prostate bed motion was calculated by measuring the position of the TFM relative to the pelvic bony anatomy on daily cone-beam computed tomography. The stability and visibility of the TFM were assessed in the initial 10 patients. Results: No postoperative complications were recorded. A total of 3,500 images were analysed. The calculated prostate bed motion for bony landmark matching relative to TFM were 2.25 mm in the left-right, 5.89 mm in the superior-inferior, and 6.59 mm in the anterior-posterior directions. A significant 36% reduction in the mean volume of rectum receiving 70 Gy (rV₇₀) was achieved for a uniform planning target volume (PTV) margin of 7 mm compared with the Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group recommended PTV margin of 10 mm. Conclusion: The use of TFM was safe and can potentially eliminate set-up errors associated with bony landmark matching, thereby allowing for tighter PTV margins and a consequent favourable reduction in dose delivered to the bladder and rectum, with potential improvements in toxicities.

Current role of multiparametric magnetic resonance imaging in the management of prostate cancer

Nikolas Christopher Katelaris,Damien Michael Bolton,Mahesha Weerakoon,Liam Toner,Phillip Mark Katelaris,Nathan Lawrentschuk 대한비뇨의학회 2015 Investigative and Clinical Urology Vol.56 No.5

The purpose of this review was to evaluate the current role of multiparametric magnetic resonance imaging (mp-MRI) in the managementof prostate cancer (PC). The diagnosis of PC remains controversial owing to overdetection of indolent disease, whichleads to overtreatment and subsequent patient harm. mp-MRI has the potential to equilibrate the imbalance between detectionand treatment. The limitation of the data for analysis with this new technology is problematic, however. This issue has been compoundedby a paradigm shift in clinical practice aimed at utilizing this modality, which has been rolled out in an ad hoc fashionoften with commercial motivation. Despite a growing body of literature, pertinent clinical questions remain. For example, can mp-MRI be calibrated to reliably detect biologically significant disease? As with any new technology, objective evaluation of the clinicalapplications of mp-MRI is essential. The focus of this review was on the evaluation of mp-MRI of the prostate with respect to clinicalutility.

Incidence of Bladder Cancer in Sri Lanka: Analysis of the Cancer Registry Data and Review of the Incidence of Bladder Cancer in the South Asian Population

Weranja K. B. Ranasinghe,Daswin De Silva,M.V.C. De Silva,Tamra I J Ranasinghe,Nathan Lawrentschuk,Damien Bolton,Raj Persad 대한비뇨의학회 2012 Investigative and Clinical Urology Vol.53 No.5

Purpose: To investigate the incidence of bladder cancer (BC) in Sri Lanka and to compare risk factors and outcomes with those of other South Asian nations and South Asian migrants to the United Kingdom (UK) and the United States (US). Materials and Methods: The incidence of BC in Sri Lanka was examined by using two separate cancer registry databases over a 5-year period. Smoking rates were compiled by using a population-based survey from 2001 to 2009 and the relative risk was calculated by using published data. Results: A total of 637 new cases of BC were diagnosed over the 5-year period. Sri Lankan BC incidence increased from 1985 but remained low (1.36 and 0.3 per 100,000 in males and females) and was similar to the incidence in other South Asian countries. The incidence was lower, however, than in migrant populations in the US and the UK. In densely populated districts of Sri Lanka, these rates almost doubled. Urothelial carcinoma accounted for 72%. The prevalence of male smokers in Sri Lanka was 39%, whereas Pakistan had higher smoking rates with a 6-fold increase in BC. Conclusions: Sri Lankan BC incidence was low, similar to other South Asian countries (apart from Pakistan), but the actual incidence is likely higher than the cancer registry rates. Smoking is likely to be the main risk factor for BC. Possible under-reporting in rural areas could account for the low rates of BC in Sri Lanka. Any genetic or environmental protective effects of BC in South Asians seem to be lost on migration to the UK or the US and with higher levels of smoking, as seen in Pakistan. Purpose: To investigate the incidence of bladder cancer (BC) in Sri Lanka and to compare risk factors and outcomes with those of other South Asian nations and South Asian migrants to the United Kingdom (UK) and the United States (US). Materials and Methods: The incidence of BC in Sri Lanka was examined by using two separate cancer registry databases over a 5-year period. Smoking rates were compiled by using a population-based survey from 2001 to 2009 and the relative risk was calculated by using published data. Results: A total of 637 new cases of BC were diagnosed over the 5-year period. Sri Lankan BC incidence increased from 1985 but remained low (1.36 and 0.3 per 100,000 in males and females) and was similar to the incidence in other South Asian countries. The incidence was lower, however, than in migrant populations in the US and the UK. In densely populated districts of Sri Lanka, these rates almost doubled. Urothelial carcinoma accounted for 72%. The prevalence of male smokers in Sri Lanka was 39%, whereas Pakistan had higher smoking rates with a 6-fold increase in BC. Conclusions: Sri Lankan BC incidence was low, similar to other South Asian countries (apart from Pakistan), but the actual incidence is likely higher than the cancer registry rates. Smoking is likely to be the main risk factor for BC. Possible under-reporting in rural areas could account for the low rates of BC in Sri Lanka. Any genetic or environmental protective effects of BC in South Asians seem to be lost on migration to the UK or the US and with higher levels of smoking, as seen in Pakistan.