The role of mpMRI in monitoring of men on active surveillance

At least one paper has stated that some 40 percent of men diagnosed with low-risk prostate cancer here in the US are now being initially managed on active surveillance. If active surveillance is being done properly, this is a good thing! However, …

What “being done properly” is when we refer to active surveillance is still something of a moving target and depends on a whole variety of different factors, including:

  • The patient’s age, health status, and individual risk level
  • The patient’s level of concern about his risk for progression over time
  • Whether the patient’s physician and the patient himself have access to high quality multiparametric MRI (mpMRI) scanning capabilities and associated MRI/TRUS-fusion biopsy technology
  • The experience of the individual physician in managing patients on active surveillance

A factor that can be critical to all of this — and which has yet to be fully resolved — is the role of mpMRI in three particular scenarios:

  • The decision to place the patient on active surveillance in the first place
  • Whether serial mpMRI scans can or should be used to monitor the patient over time (and if so how often an mpMRI should be given)
  • Whether serial mpMRIs can actually “replace” serial prostate biopsies in the monitoring of men on active surveillance

So for those who are interested in a review of the current status of research into these issues, we recommend a recent review by Alam et al. from the Johns Hopkins group. The paper is entitled, “Active surveillance of prostate cancer: current state of practice and utility of multiparametric magnetic resonance imaging“, and the full text of the paper is available at the link provided.

Some readers may find the review to present a rather cautious and “conservative” mindset as to the application of mpMRI in the management of men on active surveillance. The basic “take away” points made by the authors are the following:

  • “Active surveillance (AS) is a management strategy in which men with favorable-risk prostate cancer avoid or delay immediate intervention in favor of close monitoring.”
  • “Traditionally, monitoring on AS has consisted of frequent digital rectal examination, serum PSA testing, and transrectal ultrasound-guided biopsy. New tools such as multiparametric magnetic resonance imaging (mpMRI) are being actively incorporated into previously reported protocols.”
  • “Current data have not yet identified a favorable subset of men with intermediate-risk disease. Therefore, these patients should be counseled appropriately about the potentially increased risks of AS.”
  • “There are substantial limitations to our understanding of mpMRI in the AS setting, as the majority of data have been obtained from retrospective experiences in which mpMRI was not uniformly applied.”
  • “Current data demonstrate that mpMRI alone does not preclude the need for prostate biopsy. Furthermore, systematic biopsy should continue to be performed at the time of targeted biopsy in most settings.”

With regard to the fourth bullet point just above, the authors refer readers of an article about the Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) checklist (see Moore et al.), which is a standardized protocol developed by a European School of Oncology Task Force for reporting outcomes using mpMRI in AS.

What readers need to appreciate is that — from a researcher’s perspective — the important issue is to be able to achieve two quite different and potentially conflicting ideals:

  • That no man placed on active surveillance ever gets a forms of prostate cancer that can progress to metastatic disease before it can be cured
  • That no man started on active surveillance is advised to have invasive treatment that he doesn’t really need

The individual patient is going to look at this very differently at the present time. Some will be more willing to take risks and stay on active surveillance because they value their quality of life above their risk for progressive prostate cancer. Others will be more willing to take risks with their outcome from one of many different forms of treatment because of their fear of progressive prostate cancer.

It is going to take us a while to find common ground among all parties about “the right” ways to apply mpMRI along with other tests in the management of man on active surveillance. After all, some men might well need to be on active surveillance for 25 years and longer.

10 Responses

  1. Since I do not know the answer, is mpMRI a procedure that health insurance companies will cover on a repeated basis for men having chosen active surveillance as their treatment option? If so, how many mpMRIs are authorized in a given year? Also, does Medicare as well as “all” health insurers provide this repeated service?

  2. Thanks for this and all the work you do for us, @Sitemaster. A study like this always gives me long pause. …

    BTW; the study says that 40% of newly-diagnosed, low-risk patients are managed on AS in the USA, not 40% of all new patients. I assume then your first line is referring to another study; is that the case?

  3. Dear SUM:

    Thanks for catching the missing words “low-risk”, which have now been added in above!

  4. Dear Chuck:

    The willingness of payers to cover the costs associated with mpMRIs (as compared to repeat biopsies) is an evolving situation. I don’t think there is a simple answer to your question at this time.

    With regard to frequency of mpMRIs, … if they are being done appropriately, it is hard to believe that many patients would require such a scan more than once a year (but there are always exceptions to every general rule).

  5. I am increasingly advocating a template mapping biopsy as the confirmatory biopsy (but not for follow-up biopsies after that). It has about 80% accuracy. mpMRI is not very good at finding low-grade tumors (or very small higher grade tumors that may disqualify the patient from staying on AS), yet those are the areas that bear watching in follow-up biopsies. I think it’s a good idea to get one good whole-gland map of where the cancer is. It’s just my hypothesis — it would make a good randomized clinical trial.

  6. Allen:

    I worry about the potential complications of template mapping biopsies in all but the most experienced and skilled centers.

    If they were going to do a trial, it would be meaningless if it was just done at academic centers.


  7. That’s a good point. I would make the same point about mpMRIs — their availability has far outreached the number of experienced radiologists capable of correctly interpreting them. For now, I think the use of both should be limited to experienced academic centers.

  8. DearAllen:

    The situation with mpMRIs is actually somewhat different because it is now commonplace for MRI data to be read remotely through the application of telemedicine. In other words, so long as the MRI is being appropriately conducted, it can be read by an appropriately experienced uroradiologist almost anywhere. I think the condition should be that such mpMRIs are indeed being read by suitably qualified and experienced radiologists … but they don’t necessarily have to be locally available.

  9. Do you have a sense of how often that happens in the real world? My sense is that radiologists without a lot of experience think they are better at it than they are. (BTW — the same holds true for pathologists reading biopsy cores.) As with everything in medicine, the better doctors and diagnosticians are not accessible to patients in remote communities, and unless they make an effort to talk to people like us on the Internet, they will get substandard care without ever knowing that anything better is available.

  10. I know that tele-radiology is quite common. Do I know exactly how it is applied in the case of reading mpMRIs? No. I don’t.

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