The CaP Calculator: a new, sophisticated, decision-support tool


Long, long ago (in September 2008), we initially reported on the existence of a prostate cancer decision support tool (then in very early-stage development) known as the CaP Calculator. The creator of this calculator, Dr. Matthew Katz, informed us this morning that the first publication giving complete details about the CaP Calculator and its use has just been published online in BJU International, and he kindly provided us with full copy of the article.

The CaP Calculator, like other prognostic calculators and nomograms, is designed to assist physicians and their patients in doing two things:

  • Estimating disease extent based on data available at the time of diagnosis
  • Projecting outcomes of patients based on data available at the time of diagnosis and their proposed treatment

What distinguishes the CaP Calculator from other decision support tools for prostate cancer is that it has been designed to provide results based on a range of different models already available. In other words, instead of having to pick one particular nomogram or calculator or set of tables (e.g., the Kattan nomograms or the Partin  tables), the CaP Calculator provides its users with data from several models at once — thus giving the doctor and his patient a more complete range of data that they can use together to make treatment decisions.

We are not going to give a detailed discussion of all of the details of the CaP Calculator here. Such information is already available in a thorough and well-presented format on the CaP Calulator web site, as follows:

Among the more impressive things that Dr. Katz has been able to do in building this new calculator is to enlist the help and support of many prominent members of the urology and radiation oncology communities who have been involved in developing the earlier tools on which this calculator is based. You just have to look at the names of the participants in the development of the calculator and the coauthors of the initial paper referred to earlier to see that academic specialists with an interest in prostate cancer decision-support tools have put their full support behind this project over the past 18 months.

So what does the CaP Calculator do for patients?

It must be emphasized that the CaP Calculator has been designed for use primarily by physicians and other health care professionals, and not primarily intended for direct use by patients. The reason for this is twofold. First, to get the best out of the calculator, you may have to be able to enter a lot of very specific data (e.g., the exact percentage of cancer in each biopsy core, and the presence or absence of Gleason grade 4 or 5 cancer in each core). Not all of these data would necessarily be easily available to patients. Unlike other online decision support tools, you can’t get the best out of the CaP Calulator if you just enter a PSA level, a Gleason score, a clinical stage, and limited data about numbers of positive and negative biopsy scores. Second, interpretation of the output of the CaP Calculator is dependent on the actual input, and — because the calculator gives a range of possible outcome data — interpreting the output appropriately also requires significant clinical experience.

The “New” Prostate Cancer InfoLink would like to think that, over time, the CaP Calculator will:

  • Become a standard tool for decision-support across the surgical and radiation oncology community in helping doctors and their patients to some to the best possible decisions about treatment of localized prostate cancer
  • Continue to evolve as new data come available for long-term outcomes from active surveillance, HIFU, and focal therapy
  • Evolve such that a more “patient friendly” version of the calculator can be accessible to patients and family members that could perhaps include some online guidance as to how to best interpret the calculator’s output for discussion with one’s doctor.

From this point on, however, The “New” Prostate Cancer InfoLink (both here and through our associated social network) intends to regularly advise patients with newly diagnosed, localized prostate cancer (i.e., clinical stage T1-T3) to ask their doctors to “run their numbers” through the CaP Calculator to estimate both the extent of their disease and their potential outcomes based on relevant treatment data available.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: