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Posts tagged ‘Radical Prostatectomy vs Watchful Waiting’

PIVOT-prostate-cancer-intervention-versus-observation-trial-dataTimothy J. Wilt MD, MPH presented an update on the VA, NCI, AHRQ Prostate cancer Intervention Versus Observation Trial (PIVOT) on the final day of the 2012 European Association of Urology (EAU) Congress in Paris.

I previously wrote on this blog about the PIVOT data presented by Professor Wilt in the plenary session at the 2011 American Urological Association Annual meeting.

The PIVOT trial objective according to Dr Wilt, was to answer the following question:

Among men with clinically localized prostate cancer detected during the early PSA era, does the intent to treat with radical prostectomy reduce all-cause & prostate cancer mortality compared to observation?

PIVOT enrolled 731 men from 1994 to 2002 who were randomized to either receive radical prostatectomy or undergo just observation.

The results from the trial provide level 1 evidence based medicine (highest standard) concerning the survival benefits conferred by radical prostactectomy (with the potential for quality of life impacts such as incontinence & erectile dysfunction), as compared to not undertaking surgery, but instead doing observation only in the form of watchful waiting or active monitoring.

Dr Wilt told the urologists in the EAU 2012 Congress plenary session, that after a median follow-up of 10 years (interquartile range = 7.3 to 12.6), the median survival was 12.7 years. Wilt told the audience that:

“Prostate cancer mortality was uncommon occurring in only 7.1% of men, it did not vary considerably by patient age, race, comorbidities or health status, but did vary considerably by tumor risk status ranging from 3 % in men with low risk disease to 13 % in men with high risk disease.”

PIVOT Prostate Cancer Mortality Results

No of Deaths: 52/731 (7.1%)

    • Low risk  (3.4%)
    • High risk (8.4%)
    • High risk (13.3%)

In the men who had death judged to be due to prostate cancer, absolute differences between treatments were less than 1%,” Wilt said.

As far as I could determine, the data presented at EAU 2012 was no different from the PIVOT data presented at AUA 2011 other than being another year mature.

A subgroup analysis showed that surgery conferred no survival benefit over watchful waiting except for high-risk patients.  In his EAU 2012 presentation, Dr Wilt described the subgroup findings in more detail (emphasis added):

Low Risk Prostate Cancer

“In men with low risk prostate cancer, disease mortality occurred in less than 3% and did not differ between radical prostatectomy and observation”  (HR=1.48; ARR=1.4, P=0.54). This favored observation.”

High Risk Prostate Cancer

“Among men with high risk tumors, prostate cancer mortality occurred in approximately 13%. Radical prostatectomy produced a 60% relative risk reduction  (HR = 0.4, ARR = 8.4) of borderline significance (P=0.04).

Intermediate Risk Prostate Cancer

“Among men with intermediate risk prostate cancer, we found a non-significant reduction of 4.6%.”

PSA <= 10ng/ml

“In men with PSA <= 10ng/ml there was no significant difference between radical prostatectomy and watchful waiting.” (HR = 0.92, ARR=0.3%, P=0.82).  The findings were virtually identical throughout the course of the study. The lines are essentially superimposable for prostate cancer mortality in men treated with observation or with radical prostatectomy.”

PSA > 10ng/ml

“Among men with baseline PSA > 10ng/ml, radical prostatectomy reduced prostate cancer death by a relative 64% and an absolute difference of 7.2%. You can see the curves begin to separate at approximately 7 years.” (HR=0.36, ARR= 7.2%, P=0.03)

PIVOT-Prostatectomy-versus-observation-data-conclusion-2012Dr Wilt’s conclusion based on the latest study data was that:

“In men with localized prostate cancer detected during the early PSA era, radical prostatectomy compared to observation did not significantly reduce all-cause and prostate cancer mortality. Absolute differences through at least 12 years were less than 3%” 

These results are important findings that should impact the treatment of men diagnosed with early stage, low risk prostate cancer.

The fact that the survival curves do not diverge except for high-risk patients presenting with a PSA > 10ng/mL, may also have an impact on the ongoing PSA prostate screening debate.

If the PIVOT data results in more men being put on watchful waiting/active monitoring, then it should lower the overtreatment that screening currently produces.  Urologists will, however, need to be prepared to counsel their patients accordingly and forego the economic benefits that undertaking surgery affords many of them.

Urologists at the EAU in Paris greeted the PIVOT trial data in silence and an absence of social media interaction (I did not see any urologists tweet enthusiastically about it).

Many urologists who have trained many years to perform complex surgical techniques may find the idea of watchful waiting an anathema.

Adopting a policy of watchful waiting in many prostate cancer patients may also place economic pressures placed on those urologists who need a throughput of patients to recover or amortize the cost of expensive technology such as the da Vinci robotic system.

The PIVOT trial data is, however, level 1 evidence based medicine that cannot be ignored.

Hopefully, this analysis of the PIVOT trial data will be published in a peer-reviewed journal in the not too distant future so that it can reach a wider audience than those urologists who attended the AUA 2011 and EAU 2012 plenary sessions.

Update July 18, 2012

The results of the PIVOT trial presented at AUA 2011 and EAU 2012 have been published in the New England Journal of Medicine (online first, July 18, 2012).

NEJM PIVOT prostate cancer

A survey of patients who had their prostate removed showed there was no significant difference in complication rates between open retropubic radical prostatectomy (ORRP) and robotic assisted laparoscopic surgery (RALRP).

This is an important finding because 85% of prostatectomies in the United States are undertaken using robotic-assisted techniques, yet there has been little published data to show that this technique improves functional outcomes.

At the European Association of Urology (EAU) annual congress last year in Vienna some of the challenges and opportunies with robotic surgery were raised:

  • lack of data on improved functional outcome
  • need for licensing of robotic surgeons
  • high learning curve – it takes 250 patients to become proficient

In reality, we see hospitals marketing their robotic surgery to patients in shopping malls and with advertisements on the side of buses.  You can read Gary Schwitzer’s thoughts on some of the recent marketing claims & “gizmo idolatry.”

This is why a survey comparing the results of open to robotic assisted prostate removal surgery is important evidence based medicine. Published online first in the Journal of Clinical Oncology, Barry and colleagues randomly surveyed 800 men who filed Medicare claims between August and December 2008.  685 completed surveys were returned, and information on adverse events was obtained.

The data highlights the dramatic effect on quality of life that prostate cancer surgery can have, irrespective of the surgical technique. The men rated themselves:

31.1% – moderate or big problem with continence  (95% CI 27.5 to 34.8%)

88.0% – moderate or big problem with sexual function (95% CI 85.4% to 90.6%)

Breaking this down by technique (robotic surgery versus open prostatectomy):

Continence: 27.1% of men (Open) versus 33.3% (Robotic) – not significant (P=0.113)

Sexual Function: 89.0% of men (Open) versus 87.5% (Robotic) – not significant (P=0.57)

The authors conclude in their JCO paper:

Our results do not demonstrate a lower risk of problems with incontinence or sexual function after RALRP compared with ORRP.

In fact, after adjusting for potential confounders, there was at least a strong trend toward a higher risk of patient-reported moderate or big problems with incontinence following RALRP.

The authors in their discussion do raise the interesting question as to whether patients were led to believe that they would have fewer side effects with robotic surgery, which may have impacted the survey findings.  This merits further investigation.

There is clearly a need for patients to give informed consent, and be aware of the risks and complications of prostate cancer surgery, particularly with regards fundamental quality of life issues such as continence or sexual function.

The accompanying JCO editorial by Matthew Cooperberg and colleagues from UCSF is well worth reading and raises the question as to whether men with prostate cancer should expect better outcomes than those reported in the survey?

What the survey by Barry et al did not do is look at the volume of procedures and experience level of the surgeon, both of which are associated with outcomes.

Cooperberg noted that “surgeons performing fewer than 5 prostatectomies per year account for approximately half the national volume.

A chilling statistic, and if you factor in the learning curve of more than 200 procedures to be competent at robotic surgery, it is perhaps not surprising that some men experience higher complication rates than others.

Which brings me back to the importance of the PIVOT (Prostate Cancer Intervention versus Observation Trial) data presented in the plenary session at the 2011 annual meeting of the American Urological Association (AUA) in May last year.

Why has this practice changing data not been published in a peer-reviewed journal yet?

The fact that the updated PIVOT study results presented at AUA 2011 have not been published (to the best of my knowledge) is a disservice not only to the medical and scientific community, but to men with prostate cancer whose treatment should be guided by evidence-based medicine.

The long-term results of the PIVOT trial presented by Professor Wilt showed no benefit of radical prostatectomy over watchful waiting, except for high-risk patients.  Yet, the reality is that many men end up having surgery. This may be considered overtreatment and an exposure of more men than is necessary to the complications of prostatectomy, irrespective of whether this is robotic or open surgery.

The decision to undergo radical prostatectomy should be an informed one, not only as to the risks and benefits of the surgical technique, but also whether the surgery should be performed in the first place as compared to “watchful waiting.”

I hope the paper and editorial published in the JCO this month will generate some debate. Next month I will be at the European Urology Association annual congress in Paris.


ResearchBlogging.orgBarry, M., Gallagher, P., Skinner, J., & Fowler, F. (2012). Adverse Effects of Robotic-Assisted Laparoscopic Versus Open Retropubic Radical Prostatectomy Among a Nationwide Random Sample of Medicare-Age Men Journal of Clinical Oncology DOI: 10.1200/JCO.2011.36.8621

Cooperberg, M., Odisho, A., & Carroll, P. (2012). Outcomes for Radical Prostatectomy: Is It the Singer, the Song, or Both? Journal of Clinical Oncology DOI: 10.1200/JCO.2011.38.9593

Update August 12, 2012 – Paper published in European Urology shows lower incontinence and greater rate of erection recovery with robot-assisted radical prostatectomy

A paper published online (July 20, 2012) in the journal, European Urology by Franceso Porpiglia provides some evidence that robot-assisted radical prostatectomy offers functional benefits to patients. I have not read the full paper only the freely available abstract.

The clinical trial evaluated the functional outcomes of 120 men in a randomized clinical trial where half (n=60) received radical prostatectomy (RARP) that was robot-assisted and the other half (n=60) who had the operation laparoscopically without robot assistance (LRP).

Following the surgery performed by Dr Porpiglia, the functional outcomes between the two groups were compared. Those men operated on with robot assistance showed:

  • Lower incontinence. “Continence after 3 mo was 80% in the RARP group and 61.6% in the LRP group (p = 0.044), and after 1 yr, the continence rate was 95.0% and 83.3%, respectively (p = 0.042)”
  • Better erection recovery. “Among preoperative potent patients treated with nerve-sparing techniques, the rate of erection recovery was 80.0% and 54.2%, respectively (p = 0.020).”

The challenge of this study is that although it was randomized, it reflects the results of only one surgeon with a small number of patients.

Dr Matthew Cooperberg (@cooperberg_ucsf) was quoted by Reuters saying that this was likely the best study we were going to get showing the benefits of RARP over LRP. On twitter he said the real question was now between radical prostatectomy and external radiation therapy (XRT).

Data from the Prostate Cancer Intervention versus Observation Study (PIVOT) presented today in the plenary session of the 2011 annual meeting of American Urological Association (AUA) will have a major impact on the practice of Urology.

The VA/NCI/AHRQ cooperative study, initiated in 1994, was designed to assess the effect of radical prostatectomy (RP) compared to observation only or “watchful waiting” in men with localized prostate cancer.

What makes the PIVOT study so important is that it is the first randomized trial in the United States to look at RP versus “watchful waiting.”  In all, 13,022 men were screened at 52 US centers, from which 5023 men were deemed eligible.  Surprisingly, 4292 declined randomization and 731 men were enrolled in the trial.

The primary endpoint was all-cause mortality and the secondary endpoint, Prostate Cancer (PCa) mortality.  The two groups of patients were comparable between the observation and RP groups (mean age 66.8, 67.0 years); PSA Mean (10.2, 10.1), Gleason Score < 6 (70.1%, 69.8%).

Timothy Wilt (Minnesota) presented the results today at AUA 2011 (Abstract#407)

All-Cause Mortality

  • Absolute Risk Reduction (ARR) between Observation & RP = 2.9%,
  • Hazard Ratio = 0.88 (95% 0.71-1.08), P=0.22



Prostate Cancer Mortality – all patients

  • AR = 2.7%  (95% CI -1.3 to 6.2)
  • Hazard Ratio=0.63 (95% CI 0.36-1.09), p=0.09

In other words looking at the groups as a whole there was no benefit of RP on survival.  Wilt presented further analysis on subgroups with low-risk local pathology, intermediate risk-local pathology and high risk PSA>10.

Only in the high-risk groups (PSA>10) was there a significant benefit to RP, in terms of lowering Prostate Cancer Mortality.

  • HR= 0.36 (0.15 to 0.89); p=0.03
  • ARR = 7.2% (0 to 14.8)

Wilt’s conclusion from the data was that compared to observation, RP produced

“reductions in all-cause and prostate cancer mortality that were not significant and less than 3% in absolute terms over 12 years.”

He added that:

“Surgery did not reduce mortality more than observation in men with low PSA or low risk from Prostate Cancer”

However, these “results suggest a benefit from surgery in men with higher PSA or higher risk of disease.”

The PIVOT trial provides evidence-based medicine results that will directly influence how urologists treat early stage prostate cancer.  Several urologists and others at AUA tweeted about the PIVOT data.  Using Storify, these provide some sentiments and perspective from practicing urologists in the live audience.

The conclusion from this data is that low risk, early stage prostate cancer patients should be observed by “watchful waiting” rather than undergo radical prostatectomy (RP).  This may have a financial impact on urologists who previously may have favored RP in low risk patients.

Update May 23, 2011

A webcast with audio and slides of Dr Wilt’s plenary presentation of the PIVOT data is now available on the AUA website.

Update March 6, 2012

Dr Wilt presented an update on the PIVOT trial at the 2012 European Association of Urology (EAU) Congress in Paris. You can read my blog post from the meeting:

PIVOT data continues to show no survival benefit for prostatectomy over watchful waiting in men with low to medium risk early prostate cancer.”

 Update July 18, 2012

The data from the PIVOT trial presented in the plenary sessions at AUA 2011 and EAU 2012 has finally been published online first (July 18, 2012) in The New England Journal of Medicine.NEJM PIVOT trial prostate cancer

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