Prostate Cancer Questions Answered
Article date: August 27, 2008
Prostate cancer affects tens of thousands of men in the United States every year. Screening can often find this cancer in its early stages. Yet the question of whether men should be routinely screened for prostate cancer is not clear-cut.
Here, the American Cancer Society's Chief Medical Officer, Otis Brawley, MD, answers some common questions about prostate cancer screening and the Society's recommendations.
The American Cancer Society does not have a blanket recommendation for prostate cancer screening for men over the age of 50. The ACS convened a panel of experts to look at the data and that panel recommends that men with more than a 10-year life expectancy be given the option of screening within the healthy person physical examination. This recommendation realizes that screening has not been proven to save lives, but screening might save lives. It also recognizes that there are some proven harms associated with screening. Screening, for example, leads to unnecessary treatment in some men who are diagnosed with localized disease. While screening has not been proven to save lives, it may. The ACS calls for informed decision making.
It is true that many organizations have looked at the same data and determined that screening cannot be recommended at this time and some even recommend against screening. These latter groups only recommend screening modalities that are proven to save lives.
The ACS also recommends that men at high risk for prostate cancer be given the option of screening beginning at age 45. Men at high risk include men with a family history, meaning a brother or father with a diagnosis of prostate cancer before age 65. Men of African heritage are also considered at high risk.
The US Preventive Services Task Force recently reviewed the scientific literature and concluded that evidence of screening benefit is extremely limited. They decided they cannot recommend for or against screening among men age 50 to 75, and they recommend against screening for men age 75 and above. The ACS recommendation recognizes the limits of the science and suggests that men be involved in the decision to be screened or not be screened. We do not put an upper age limit on who should be given the option of screening but suggest that men with less than a 10-year life expectancy not be screened. The average 75-year-old American male has a life expectancy of about 10 years. The ACS recommendation recognizes that there are some 75- and 80-year-olds in better-than-average health with more than a 10-year life expectancy. We recommend they be given the option of screening. Both the US Preventive Services Task Force and ACS recommend that men at high risk might choose to start screening earlier. The American College of Physicians and American Academy of Family Physicians actually recommend against prostate cancer screening, but they do suggest that the patient and physician discuss screening.
Prostate cancer is a major killer. We are truly handicapped by the fact that screening and many of the commonly used treatments have not been proven to save lives. All the major professional organizations in the US, Canada, and Europe recognize that screening has not been shown to save lives.
It is difficult to comprehend, but there are prostate cancers that are confined to the prostate and never destined to metastasize (spread to other parts of the body). Screening diagnoses a large number of men who would never be bothered by the disease. In one clinical trial, more than 12% of average risk men were diagnosed through screening over 7 years. This group of men is estimated to have a lifetime risk of death of less than 4%. This study suggests that 2 out every 3 men in this study did not need to be diagnosed nor treated. While this study suggests that the proportion of men in the overall population who are diagnosed with cancers that do not need therapy is as high as 67% of men with localized disease, others estimate it to be as low as 30%. We have very poor ways of predicting who needs treatment because their prostate cancer might kill them, and who does not need therapy because their tumor is of no threat to them.
Many health care provider organizations and many well-meaning community groups encourage prostate cancer screening and offer mass screening at health fairs and other activities. The American Cancer Society is concerned that so many do not understand that the benefits of screening are still undetermined. The ACS recommends against such mass screening activities because one cannot be assured that the patient has the opportunity to hear a balanced explanation of screening in an environment in which he can feel comfortable to ask questions and make an informed decision.
A man considering screening should know that there is a chance he will be diagnosed with a disease that may lead to unnecessary treatment. The treatment can cause urinary incontinence, impotence, and even death. The man should also know that some experts believe that some men do benefit from screening in that their life could be saved. We know of the harms of screening, as scientific study has proven them to exist; the benefits are a theoretic possibility as yet unproven. A man who is very worried about prostate cancer might choose to get screened. A man who is less concerned with prostate cancer might choose not to be screened. Both decisions are appropriate and reasonable and should be respected.
There are several accepted treatments for early or potentially localized prostate cancer. Certain of these treatments may be more appropriate for specific patients given their prostate cancer stage, certain pathology features of the disease, and the general health of the patient. It is important that every patient review all the available treatments and choose a modality in which he is comfortable. Patients should ask their physician what treatments they are eligible for.
Radical prostatectomy, or surgery, is the treatment with the longest history. Radiation therapy, either external beam or by brachytherapy (seed implant) are accepted standard treatments appropriate for many men. Radiation and surgical side effects and efficacy can be very similar. Cryotherapy, or freezing, of the prostate is being assessed in certain centers.
Treatment options for more advanced disease are more limited. Radiation and/or hormonal therapy are the mainstays, and chemotherapy is used in cases that are non-responsive to hormonal therapy. It is imperative that the patient have a good conversation with his physicians about treatment options.
A large proportion of prostate cancers diagnosed through screening will never grow, spread and cause death. Given the stage and pathologic features of a cancer, as well as the age and health of the patient, some patients may reasonably choose "observation therapy," which is also called "watchful waiting," in lieu of aggressive initial treatment. This involves active observation and monitoring of the prostate, often with physical examination, blood tests (including PSA), and transrectal ultrasounds. If the tumor appears to be progressing, more aggressive therapy may be started. In some studies of men choosing observation therapy, nearly half never received any aggressive prostate cancer treatment in their lifetime. These men died "with prostate cancer" and not "of prostate cancer."
Reviewed by: Members of the ACS Medical Content Staff
ACS News Center stories are provided as a source of cancer-related news and are not intended to be used as press releases.
Thank you for your feedback.