THE "NEW" PROSTATE CANCER INFOLINK

A recent article in the Journal of Urology offers some insight into the risk for a diagnosis of prostate cancer in a large, relatively young cohort of men undergoing regular health checks in the period between 1991 and 2008.

del Junco et al. have reviewed data on the incidence of prostate cancer in United States Air Force (USAF) servicemen aged between 35 and 64 years.  Since the mid 1990s, these service personnel have been required to have regular, periodic health assessments. However, mandatory PSA tests were not included until 2003. Data for the period 1991-94 predate the necessity for periodic health assessments, and (for context) it is worth knowing that, as of May 2009, the USAF had some 320,000 active military service personnel.

The authors were able to use the available data to determine age-adjusted prostate cancer incidence rates over time, how these tumors segregate into low and intermediate/high risk categories, and information on subsequent treatment choice.

The key findings are as follows:

• The absolute number of newly diagnosed cases of prostate cancer per year was low (29 in 1991-94; 83 in 1995-99; 127 in 2000-04; 98 in 2005-08).
• Age-adjusted rates of prostate cancer in white active duty servicemen diagnosed between 2005 and 2008 (when PSA testing was provided) were three times higher than the age-adjusted rates between 1991 and 1994 (before mandatory periodic health assessments).
• A similar trend was evident in black servicemen, but the numbers of men involved was too small to draw conclusions about the increase in risk.
• Prostate cancer rates in active duty USAF service personnel between 1995 and 2008 were significantly higher that those calculated for the Surveillance, Epidemiology and End Results population for the two racial groups.
• A significantly higher percentage of active duty servicemen than retirees (62 vs 40 percent) presented with low-risk disease.
• Among patients with low-risk disease, significantly more active duty servicemen elected surgical treatment than retirees (93 vs 53 percent).

Unfortunately, even though we know that the authors broke down the numbers of men diagnosed into six 5-year-long age groups (35-39, 40-44, … 60-64 years), the full text of the paper does not give us that actual number of men diagnosed in each age group over the entire time period.

One needs to be careful about over-interpreting these data. For example:

• The USAF, like the rest of the U.S. armed services, has an “open access” medical system, with no cost to the individual service members.
• The mandatory periodic health assessment system, in place since 1995, means that 100 percent of active servicemen in the USAF get regular health checks, which is far higher than the situation in the general male population of the USA.
• There is a (probably slight) possibility that something about employment in the USAF may affect risk for prostate cancer.
• The high rate of selection of surgery as a treatment choice may be heavily influenced by USAF medical standards for employment (“a diagnosis or ongoing surveillance for cancer” may disqualify a serviceman from worldwide deployability or continued service).

What does seem clear from this study is that if  the entire male population of the USA was having regular health checks (and that’s a big “if”), we might be finding a lot more early cases of prostate cancer than we currently do. Whether this would simply be an added risk for a diagnosis of very low-risk, clinically insignificant cases of prostate cancer (and a concomitant increase in risk for over-treatment) is not a question that can be answered on the basis of these data.

Filed under: Diagnosis, Management, Risk | Tagged: age, health, risk, U.S. Air Force |