Good!
The correct answer is A. Men have between a 15-20% lifetime risk of developing prostate cancer. The PSA test was introduced in the late 1980s and quantifies a glycoprotein produced by the prostate that spills over into the blood. Although current guidelines differ by society, clinical practice and standard of care is to test high risk men over the age of 40 years for PSA levels. Any level greater than 4.0 ng/mL requires a prostate biopsy. The positive and negative predictive values of the test vary tremendously with patient population, but roughly 30% of patients with elevated PSA levels will have prostate cancer.
Although some physicians follow marginal elevations in PSA levels for a few months (choice B), this patient has a nearly 3-fold increase above that required for further workup (4.0ng/mL).
Just as the PSA test has poor sensitivity, its specificity (false positives) is also variable, ranging from 80-97%. For this reason, elevations may not indicate the presence of cancer, but perhaps are due to benign prostatic hypertrophy (choice C). However, until the biopsy is performed, a determination as to the cause of the PSA elevation is not possible (choice D). As stated above, roughly 30% of patients with elevated PSA levels will have prostate cancer (the probability of prostate cancer given an elevated PSA is 30%).
Since the incidence of false-negative results is approximately 30-50% (sensitivity), there is no possible way to determine that this patient is cancer free unless biopsies are taken (choice E).
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