1. Which of the following statements about prostate cancer is not true?
A. Prostate cancer incidence increases with age.
B. Most cases of prostate cancer are slowly progressive and do not cause major morbidity or lead to death.
C. Laboratory testing is available to differentiate the rapidly progressive and fatal forms of prostate cancer from those that do not rapidly progress and do not cause death.
D. The test for serum prostate-specific antigen concentration has had a significant impact on increased detection of this cancer.
The correct answer is C. Currently, there are no laboratory tests to differentiate rapidly progressive prostate cancer that leads to death from the indolent forms. A man who has been diagnosed with prostate cancer, therefore, is unable to know whether prostatectomy will be lifesaving or relatively unnecessary. This is a major dilemma at the current time because of the complications of impotence and incontinence, which may arise from prostatectomy.
2. Which one of the following statements about the clinical utility of prostate-specific antigen (PSA) is controversial?
A. It is useful to determine success of treatment.
B. It is useful as an indicator of the extent of disease, particularly bone metastases.
C. It is useful for monitoring recurrence of prostate cancer.
D. It is useful as a screening test for prostate cancer in men older than 50 years.
The correct answer is D. The use of the PSA level as a screening test for prostate cancer is highly controversial. PSA levels correlate with the size of the prostate, and, therefore, a larger gland results in a higher PSA value even if there is no prostate cancer. Men with benign prostatic hyperplasia (BPH) can also show elevations in serum PSA.
3. Which of the following choices is not used as a tumor marker for testicular cancer?
B. Lactate dehydrogenase (LD)
D. Human chorionic gonadotropin (hCG)
The correct answer is A. More than 90% of testicular cancers arise from germ cell tumors. These tumors produce substances, which include choices B, C, and D, that can be used as tumor markers. All of these markers are most useful to evaluate the patient for complete removal of the tumor and detect cancer recurrence, as well as monitor the effects of treatment to eliminate the testicular cancer.