Write a discussion preparation, analyze and evaluate the various measures of screening tests validation. Apply the concepts of sensitivity and specificity to prostate cancer screening, and evaluate the cost-effectiveness of having screenings for men over 50 years of age learn about cancer epidemiology. As the second leading cause of death in the United States, interventions to prevent cancer or to identify it early in its course would lead to improved longevity and decreased health care costs. You will also look at the predictive value of screening by examining the efficacy of prostate cancer screening programs. You will also discuss screening programs in your home state and evaluate the cost-effectiveness of screenings for men over the age of 50. The Importance of Positive Predictive Value for Prostate Cancer Screening
An excellent illustration of the importance of positive predictive value [predictive value (+)] is the prostate cancer screening controversy. Prostate cancer is the most common cancer among men in the United States; according to the National Cancer Institute over 240,000 men will be diagnosed with the disease in 2012 and 28,000 will die from it. The disease can be detected early through a simple blood test to measure levels of prostate-specific antigen (PSA). PSA is a molecule found in cells that make up the prostate gland and is released when tumors disrupt the prostate cells. The PSA test was originally developed to tell whether prostate cancer was coming back in men already treated for prostate cancer. However, doctors began giving the test to healthy men with no symptoms of prostate cancer. Routine PSA screening became widespread in the United States by 1991, a year before the start of the first large clinical trial designed to determine if PSA screening actually saved lives. Although the sensitivity of the PSA test is good, it is not perfect as not all men with prostate cancer have elevated PSA levels. The specificity is more problematic because PSA blood levels can be elevated for other reasons besides cancer. For example, as men age, their prostate glands tend to enlarge and even benign conditions of the prostate can cause elevated PSA levels, as can an infection of the prostate, a condition called prostatitis. This means that a lot of men will have definitive diagnostic tests that turn out to reveal that cancer doesnt exist. Indeed, although PSA screening can detect prostate cancer in its early, curable stages, the positive predictive value is low and 1,000 men must be screened to save 1 mans life from prostate cancer. Men with suspicious PSA levels may go on to have a prostate biopsy. This is done with a needle; usually about a dozen small cores are taken. Its unpleasant but usually uneventful. Even so, about 70 out of 10,000 biopsies result in infection, bleeding, or urinary difficulties. Men found to have prostate cancerabout 25% to 35% of men biopsiedhave a number of options. One is to closely watch cancer to see if it gets worse. In this case, the harm is anxiety and possibly waiting too long to get treatment. In the United States, most men opt for one of several available treatments for prostate cancer. These treatments are very effective at curing cancer but they have a high rate of side effects including impotence, incontinence, heart attacks, and occasionally even death from the treatment of tiny tumors that never would have killed them. After comparing those harms to the benefit of saving one life, the U.S. Preventive Services Task Force calculated that the harms of PSA screening outweigh the benefits.
Last Completed Projects
| topic title | academic level | Writer | delivered |
|---|