Prostate Cancer Screening in Singapore

Prostate cancer is the 3^rd most common cancer among men in Singapore. The rate is high at 24 men per 100,000 every year. It results in the sixth most common cancer death among men in Singapore.

Men with a family history have a higher risk of prostate cancer as are African-American men. Prostate cancer can be a slow growing cancer that just doesn’t kill anyone or it can be an aggressive cancer that spreads to other body areas and kills. The slow growing kind has a median survival of more than 10 years and many of these men die from other causes before that time. The aggressive kind has a survival average of more than 2 years. A fifty year old man has a 42 percent chance of having microscopic prostate cancer by the time he is in his seventies.

Given the evidence, there is a lack of evidence to support screening for prostate cancer in the average population. This is because too many cases of prostate cancer are indolent and slow growing. The small portion that is aggressive, already have distant metastases at the time of diagnosis and treatment is just palliative. The cancer itself is not curable. If there is a test that could identify the aggressive tumors, it would be the perfect test for checking for prostate cancer.

Current screening for prostate cancer is relatively risk free. Even a prostate biopsy has less than a 1 percent chance of complications. A prostate biopsy is uncomfortable, though, and most men would prefer not to undergo it. It can cause hematospermia (blood in the sperm), hematuria (blood in the urine) or infection. False positive tests often have a bad psychological outcome. There is a high risk of false negative biopsies so people have to worry about the biopsy missing the cancer.

Patients are subject to the risks of screening. Due to over-diagnosis, they wind up with a radical prostatectomy that leads to impotence, bowel problems, and urinary incontinence. This can happen for slow growing tumors that wouldn’t have amounted to much anyway. There is a risk of perioperative mortality that is just too unacceptable for a slow growing tumor.

There is no evidence that a PSA test or digital rectal examination can detect a cancer of the prostate with a maximum number of true positives and true negatives. Those that have a high rate of screening die at the same rate as those with a low rate of screening. There is no difference in the reduction of the rate of prostate cancer deaths.

Those who should be screened are men between 50 and 75 who are expected to live ten years or more. Men with a strong family history of prostate cancer or African Americans should be screened earlier than those with no risk factors. Patients should be counseled as to the pros and cons of screening for prostate cancer.