Screening, Uncertainty, and Health Care Costs

The other day, a clinician running a worksite health program told me how proud he was that his clinic had discovered three cases of prostate cancer over the last year.   Employers are increasingly providing incentives and even requirements that their employees undergo biometric screening, and in some instances this screening includes a prostate specific antigen (PSA) test.   It’s intuitive that screening to find prostate cancer early should save lives and should also save dollars, since early treatment must surely be less expensive than treatment of metastatic disease.

In fact, the weight of evidence appears suggests that PSA screening either saves no lives (large randomized American study), or saves a very small number of lives (large randomized European study ). The cost of PSA screening and the cascade of medical care exacts a high financial toll – and also a high toll in terms of medical complications for those found to have prostate cancer.  The slightly positive European study suggested that for every life saved 49 men would have to be treated; prostate surgery and radiation therapy very frequently lead to incontinence and erectile dysfunction.  A nonrandomized observational study comparing Medicare beneficiaries in Seattle (high rate of prostatectomy) and Connecticut  (low rate) for 15 years (1987-2001) showed higher prostate cancer mortality rate in Seattle.

This week’s JAMA   (Harvard Link)has a thoughtful review of the efficacy of both prostate cancer screening (PSA blood test), and breast cancer screening (mammography.)  Both are less effective at decreasing mortality than screening for cervical or colon cancer.  Gina Kolata reviews this in the New York Times on October 22. 

We Americans eschew uncertainty, and on my fiftieth birthday, a PSA test would reduce my uncertainty – and give me some directional information about whether or not I had prostate cancer).  However, doing this test increases overall cost without demonstrable increase in quality. Thus, performing this test actually destroys value.  We will have to give up value-destroying tests that happen to decrease uncertainty just a bit to control health care costs.

Here is the US Preventive Services Task Force report on PSA screening.  Conclusion: "Current evidence is insufficient to assess the balance of benefits and harms of screening for prostate cancer in men younger than age 75 years...Given the uncertainties and controversy surrounding prostate cancer screening in men younger than age 75 years, a clinician should not order the PSA test without first discussing with the patient the potential but uncertain benefits and the known harms of prostate cancer screening and treatment. Men should be informed of the gaps in the evidence and should be assisted in considering their personal preferences before deciding whether to be tested."