Tag Archive for: watchful waiting

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Article of the month: MRI and active surveillance for prostate cancer

Every week the Editor-in-Chief selects the Article of the Week from the current issue of BJUI. The abstract is reproduced below and you can click on the button to read the full article, which is freely available to all readers for at least 30 days from the time of this post.

In addition to the article itself, there is an accompanying editorial written by a prominent member of the urological community. This blog is intended to provoke comment and discussion and we invite you to use the comment tools at the bottom of each post to join the conversation.

Finally, the third post under the Article of the Week heading on the homepage will consist of additional material or media. This week we feature a video from Dr. Hyun M. Lee discussing his paper.

If you only have time to read one article this week, it should be this one.

Role of multiparametric 3.0-Tesla magnetic resonance imaging in patients with prostate cancer eligible for active surveillance

Bong H. Park, Hwang G. Jeon, Seol H. Choo, Byong C. Jeong, Seong I. Seo, Seong S. Jeon, Han Y. Choi and Hyun M. Lee

Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
Current address: Bong H. Park, Department of Urology, Incheon St. Mary’s Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea

OBJECTIVE

• To evaluate predictors of more aggressive disease and the role of multiparametric 3.0-T magnetic resonance imaging (MRI) in selecting patients with prostate cancer for active surveillance (AS).

PATIENTS AND METHODS

• We retrospectively assessed 298 patients with prostate cancer who met the Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, defined as T1c/T2, PSA level of ≤10 ng/mL, PSA density (PSAD) of <0.2 ng/mL2, Gleason score <7, and one or two positive biopsy cores.

• All patients underwent preoperative MRI, including T2-weighted, diffusion-weighted, and dynamic contrast-enhanced imaging, as well as radical prostatectomy (RP) between June 2005 and December 2011.

• Imaging results were correlated with pathological findings to evaluate the ability of MRI to select patients for AS.

RESULTS

• In 35 (11.7%) patients, no discrete cancer was visible on MRI, while in the remaining 263 (88.3%) patients, a discrete cancer was visible.

• Pathological examination of RP specimens resulted in upstaging (>T2) in 21 (7%) patients, upgrading (Gleason score >6) in 136 (45.6%), and a diagnosis of unfavourable disease in 142 (47.7%) patients.

• The 263 patients (88.3%) with visible cancer on imaging were more likely to have their cancer status upgraded (49.8% vs 14.3%) and be diagnosed with unfavourable disease (52.1% vs 14.3%) than the 35 patients (11.7%) with no cancer visible upon imaging, and these differences were statistically significant (P < 0.001 for all).

• A visible cancer lesion on MRI, PSAD, and patient age were found to be predictors of unfavourable disease in multivariate analysis.

CONCLUSION

• MRI can predict adverse pathological features and be used to assess the eligibility of patients with prostate cancer for AS.

 

Editorial: Multiparametric MRI and active surveillance for prostate cancer: future directions

A growing body of data exists suggesting an important role of MRI in selecting men with prostate cancer for active surveillance (AS). In the present study, Park et al. [1] show that a suspicious lesion on MRI was independently predictive of adverse pathology after radical prostatectomy (RP). This finding supports existing data suggesting that suspicious lesions on MRI confer an increased risk of disease reclassification among men enrolled in AS [2]. Indeed, in our institutional AS experience we found that men with a suspicious lesion on MRI were more likely to have biopsy reclassification with extended follow-up [3].While these data are provocative, much work remains to be done before the adoption of MRI as a standard screening tool for entry into AS for men with very low-risk prostate cancer.

Introduction of functional sequence imaging into multiparametric MRI protocols has resulted in improved detection and characterisation of clinically localised prostate cancer. However, before widespread implementation into AS protocols can occur, increased rigor and standardisation in image interpretation is needed. As in the present study, 5-point Likert scales have become an increasingly popular method of quantifying a lesions likelihood of representing cancer [1]. Still other authors have quantified a lesions level of suspicion using both weighted and non-weighted scoring systems based on the number of positive MRI sequences [3,4]. While useful for statistical analysis, these reporting methods are fraught with concerns of inter-observer variability and generalizability. Additionally, a recent report by Lee et al. [5] found that a simple measurement of lesion diameter on diffusion-weighted MRI was predictive of insignificant disease after RP. Combining the plethora of functional and morphological data obtained by multiparametric MRI into a standardised, reproducible tool will greatly facilitate implementation of MRI into current AS screening protocols.

As a step in the right direction, Stamatakis et al. [4] recently generated a nomogram for predicting biopsy reclassification in men on AS after taking into consideration both functional and morphological characteristics of MRI lesions. Adding an additional layer of complexity, they also assessed the utility of calculated values, e.g. lesion density (lesion volume/prostate volume), in predicting biopsy reclassification. Briefly, their analysis showed that the number of lesions, lesion suspicion, and lesion density were predictive of biopsy reclassification. While nomogram validation and testing of its predictive value on pathological outcomes is needed, this represents a major advance in the standardised application of MRI to AS cohorts.

Despite great strides in the application of multiparametric MRI to AS cohorts, a significant concern about the false-negative rate exists. Considering the present report, of the 35 men with no visible lesion on MRI, 14.3% men had unfavourable pathology after RP [1]. This is similar to previous studies reporting disease reclassification rates of <18% [2,6]. These men with normal imaging and high-grade cancer highlight the importance of incorporating imaging and clinical data when selecting men for AS. Better defining the false-negative rate of multiparametric MRI, and effectively identifying men with a normal MRI and high-grade disease remain major challenges.

Considering all of the available data, it is becoming increasingly clear that MRI has the potential for improving the identification of patients for whom AS would be safe. It is currently the practice at our institution to refer eligible men for multiparametric MRI before enrolment in AS. Our future scholarly efforts should be directed at the standardisation of reporting MRI data and the development of user-friendly AS criteria that synthesise MRI results with clinicopathological data.

Jeffrey K. Mullins and H. Ballentine Carter
James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA

References

  1. Park BH, Jeon HG, Choo SH et al. Role of multiparametric 3.0-Tesla magnetic resonance imaging in patients with prostate cancer eligible for active surveillance. BJU Int 2014; 113: 864–70
  2. Margel D, Yap SA, Lawrentschuk N et al. Impact of multiparametric endorectal coil prostate magnetic resonance imaging on disease reclassification among active surveillance candidates: a prospective cohort study. J Urol 2012; 187: 1247–52
  3. Mullins JK, Bonekamp D, Landis P et al. Multiparametric magnetic resonance imaging findings in men with low-risk prostate cancer followed using active surveillance. BJU Int 2013; 111: 1037–45
  4. Stamatakis L, Siddiqui MM, Nix JW et al. Accuracy of multiparametric magnetic resonance imaging in confirming eligibility for active surveillance for men with prostate cancer. Cancer 2013; 119: 3359–66
  5. Lee DH, Koo KC, Lee SH et al. Tumor lesion diameter on diffusion weighted magnetic resonance imaging could help predict insignificant prostate cancer in patients eligible for active surveillance: preliminary analysis. J Urol 2013; 190: 1213–7
  6. Guzzo TJ, Resnick MJ, Canter DJ et al. Endorectal T2-weighted MRI does not differentiate between favorable and adverse pathologic features in men with prostate cancer who would qualify for active surveillance. Urol Oncol 2012; 30: 301–5

 

Video: MRI can assess the eligibility of patients with prostate cancer for AS

Role of multiparametric 3.0-Tesla magnetic resonance imaging in patients with prostate cancer eligible for active surveillance

Bong H. Park, Hwang G. Jeon, Seol H. Choo, Byong C. Jeong, Seong I. Seo, Seong S. Jeon, Han Y. Choi and Hyun M. Lee

Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
Current address: Bong H. Park, Department of Urology, Incheon St. Mary’s Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea

OBJECTIVE

• To evaluate predictors of more aggressive disease and the role of multiparametric 3.0-T magnetic resonance imaging (MRI) in selecting patients with prostate cancer for active surveillance (AS).

PATIENTS AND METHODS

• We retrospectively assessed 298 patients with prostate cancer who met the Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, defined as T1c/T2, PSA level of ≤10 ng/mL, PSA density (PSAD) of <0.2 ng/mL2, Gleason score <7, and one or two positive biopsy cores.

• All patients underwent preoperative MRI, including T2-weighted, diffusion-weighted, and dynamic contrast-enhanced imaging, as well as radical prostatectomy (RP) between June 2005 and December 2011.

• Imaging results were correlated with pathological findings to evaluate the ability of MRI to select patients for AS.

RESULTS

• In 35 (11.7%) patients, no discrete cancer was visible on MRI, while in the remaining 263 (88.3%) patients, a discrete cancer was visible.

• Pathological examination of RP specimens resulted in upstaging (>T2) in 21 (7%) patients, upgrading (Gleason score >6) in 136 (45.6%), and a diagnosis of unfavourable disease in 142 (47.7%) patients.

• The 263 patients (88.3%) with visible cancer on imaging were more likely to have their cancer status upgraded (49.8% vs 14.3%) and be diagnosed with unfavourable disease (52.1% vs 14.3%) than the 35 patients (11.7%) with no cancer visible upon imaging, and these differences were statistically significant (P < 0.001 for all).

• A visible cancer lesion on MRI, PSAD, and patient age were found to be predictors of unfavourable disease in multivariate analysis.

CONCLUSION

• MRI can predict adverse pathological features and be used to assess the eligibility of patients with prostate cancer for AS.

 

Not So Watchful Waiting?

SPCG-4 of Robotic Prostatectomy versus WW: April #urojc summary

This month’s twitter based international urology journal club, found by using #urojc, kicked off with the highly anticipated 20 year follow-up of the Scandinavian Prostate Cancer Group Study Number 4 (SPCG-4). This article had twitter buzzing in mid-March when it was published in the New England Journal of Medicine making it an ideal article for April’s journal club. This paper became an instant urology “classic.”

Bill-Axelson et al. published this 18 year follow up of a randomized control trial which separated individuals with early prostate cancer into two groups: watchful waiting or radical prostatectomy. Notable results of the study included a relative risk reduction of 44% from prostate cancer for those who underwent a radical prostatectomy compared to with watchful waiting with the NNT = 8, decreased use of androgen-deprivation therapy in this group, and the benefit of surgery being the most prominent in men <65 years with a 55% decrease in the relative risk of death due to prostate cancer.

Given that these results contradict the well known results of the Prostate Cancer Intervention versus Observation Trial (PIVOT), which started after the advent of PSA screening – the discussion of this article was particularly interesting. They are however, very different studies in terms of era and the populations studied.

During the 48 hour discussion period, key topics discussed were:

  • The applicability of these findings given the many advances in prostate cancer screening, diagnosis, and treatment since the 1990’s
  • The factors that influence the NNT
  • The impact of androgen deprivation therapy within both groups
  • How to weigh the impact of adverse effects including erectile dysfunction and urinary incontinence especially in the context of today’s treatment which includes radiation therapy, an option not addressed in this SPCG-4 study
  • The importance of this study should we face the possibility of shifting back to a pre-PSA era with the new USPSTF recommendations regarding PSA screening

As soon as the discussion opened, a question was posed if this was considered a contemporary cohort:

However, this thought was countered by:

The conversation continued to include the importance of time in NNT as pointed out Stacy Loeb. The point was later made, that the NNT might actually be lower with today’s advents of management in high-risk cancer patients.

There was a brief discussion on the statistic that 60% of the participants in the watchful waiting group underwent ADT treatment versus only 40% in the radical prostatectomy group.

Impact of adverse effects was also briefly discussed. The article stated that 84% of prostatectomy patients had ED versus 80% of the patients in WW.  However, incontinence was only present in 11% of the watchful waiting group versus 40% of the surgery group. These statistics are interesting to compare, when the third option of radiation therapy is introduced. With RT being a viable alternative today compared to the 1990’s when the initial enrollment for the SPCG-4 study was done, weighing the risk/benefits of treatment becomes much more complicated.

The importance of weighing QOL was not forgotten during this discussion.

Finally, there was some great conversation alluding to the relevance of this study in the future given the new guidelines of the USTPSF which recommend against using PSA to screen for prostate cancer in healthy men of all ages on the account that there is no realized benefit.

Overall the importance of this study can be easily summarized as follows:

We welcomed a new member!

A huge thank you to the American Urological Association who supported the Best Tweet prize of a video box set. The winner is Fardod O’Kelly for the following tweet:

Thank you to everyone who joined the discussion. We look forward to seeing you at the May #urojc! 

Meena Davuluri is a 3rd year medical student at Upstate Medical University in Syracuse, NY. She is interested in pursuing a career in Urology. Her interests include cost-effective decision analysis and health policy regarding healthcare delivery models. Follow her on Twitter @MeenaDavuluri.

 

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