Doctors answer the most frequently asked questions:
Cancer is characterized by uncontrolled growth of abnormal cells. After a while, groups of these cells form a detectable lump known as a tumour. Cancer can affect any type of cell in an organ, a gland, muscle tissue, blood or the lymphatic system. In the case of prostate cancer, the secretory cells are usually the ones that become cancerous. In theory, there are two types of prostate cancer: slow-growing and aggressive. In reality, most cases are somewhere between the two, growing at a moderate rate. For the moment, science does not have the tools to accurately predict the growth rate of a person’s cancer once it has been diagnosed.
Over time, the malignant cells in cancerous tumours can invade neighbouring tissue or organs. They may even spread to the rest of the body through the blood or lymphatic system. The presence of prostate cancer cells anywhere outside of the prostate is called metastasis. The most common sites of metastasis in prostate cancer are the lymph nodes and the bones.
Yes. Prostate cancer is the most common cancer among Canadian men (excluding non-melanoma skin cancer). According to the Canadian Cancer Society, in 2011, an estimated 25,500 Canadian men were diagnosed with prostate cancer and 4,100 died of it. Every day, on average, 70 Canadian men are diagnosed with prostate cancer and 11 die of it. One in seven men will develop prostate cancer during his lifetime (the risk is highest after age 60) and one in 28 will die of it.
Prostate cancer often develops without symptoms, and those affected are frequently completely unaware they have the disease until it is detected by a doctor. In fact, 80 percent of prostate cancer cases are discovered during routine medical checkups. Furthermore, those affected may feel perfectly healthy and be symptom-free regardless of the stage of the disease when detected.
BPH is a benign growth of the prostate. Why the prostate grows and eventually blocks the passage of urine is unclear but is considered a normal consequence of aging. As opposed to prostate cancer, the cells that grow and multiply are normal in every way and there is no risk of spread to other parts of the body. BPH does not require treatment unless symptoms are bothersome.
Our knowledge of prostate cancer is currently incomplete, particularly when it comes to risk factors. Age and family history of prostate cancer are the most important risk factors. Diet and other environmental factors may also contribute. Most men diagnosed with prostate cancer are over 65 years of age.
Men with a family history of prostate cancer run a higher risk of developing the disease and are more likely to do so at a younger age. A man whose father or brother had prostate cancer is twice as likely to suffer from the disease as someone with no family history. If two relatives had it (for example, father and a brother or two brothers), the risk is even greater. It has been determined that a familial or hereditary predisposition is found in only about 15 percent of prostate cancer cases. It appears likely that both genetics and the environment play a role in the development of prostate cancer.
It is possible that alterations in dietary intake, coupled with the consumption of certain potential micronutrients, may have an impact on prostate cancer. For now nothing is proven and approved for the prevention of prostate cancer.
Urologists and radiation oncologists usually treat prostate cancer when first diagnosed. In the case of metastasis, and especially when chemotherapy is involved, medical oncologists often become part of the team. In addition, the patient’s healthcare team (including family doctors, nurses, radiation oncology technologists and volunteers) is there to offer comfort and support.
The tests required to make the diagnosis are generally not painful but may be uncomfortable. A combination of three tests help detect prostate cancer: Digital Rectal Exam (DRE), PSA blood test and prostate biopsy. The DRE involves the doctor inserting a gloved finger into the patient’s rectum and palpating the gland. In its normal state, the prostate is smooth and rubbery. The doctor therefore checks for a lump or induration (hardening). Although useful, the DRE is by no means a perfect diagnostic test since it is not possible to examine the entire prostate. Most cases of prostate cancer diagnosed in Canada are not detected through a physical examination but with the help of PSA testing. To determine whether cancer is present requires a biopsy that is done with the guidance of an ultrasound probe placed in the rectum. This is a little painful but necessary to make the diagnosis of prostate cancer. It is only done when the DRE or PSA is abnormal.
Prostate specific antigen (PSA) is a glycoprotein (a protein mixed with a molecule of sugar) produced by normal prostate cells. A certain amount of PSA is also found in the bloodstream. The levels of PSA may vary according to age and race. The more cells there are in the prostate, the more PSA is produced; therefore, the concentration is naturally higher in men over the age of 40 because of the increased size of the gland, even if there is no cancer. In cases of cancer, more PSA may leak into the blood and therefore, in most patients, levels are higher.
Yes. PSA levels can be normal (below 4) in patients who do have the disease. According to a study published in 2004 in the New England Journal of Medicine, PSA concentrations remain normal in 15 percent of men who have the disease. This result is known as a “false negative”.
No. Elevated PSA levels indicate a prostate condition, but not necessarily prostate cancer. In addition to age, race and benign prostatic hyperplasia, the possible causes of high PSA levels include inflammation of the prostate and urinary tract infection. In most cases, levels return to normal once the problem is treated. Any trauma to the prostate (biopsy, surgery, etc) can also cause a temporary increase in PSA, leading to what is known as a “false positive” result. It is therefore very important not to jump to conclusions. It should be noted, however, that a digital rectal exam (DRE) very rarely causes such an elevation.
Not in any significant manner.
If the cancer is localized and limited to the prostate, cure is very likely and patients will have choices. Treatment will depend on the aggressivity of the cancer and on the patient’s age, life expectancy and preference. Options may include active surveillance or treatment with surgery or radiation therapy.
No. Even if the digital rectal examination or the prostate biopsies show cancer on only one side, prostate cancer is a multifocal disease and multiple microscopic cancer foci (an average of seven) are generally found throughout the prostate. This is why it is essential to remove the entire prostate in the case of surgery and to treat the entire prostate in the case of external beam radiation therapy or brachytherapy.
Doctors cannot precisely predict exactly how aggressive a newly diagnosed cancer is and the risk of progression, although they do have some tools to help guide the patient, namely the Partin tables, the Kattan nomograms and the Albertsen life tables. These helpful evaluation scales may help predict the risk the cancer poses for the patient.
No, but some prostate cancers may progress very slowly. They can be present for years and never spread, produce symptoms or threaten the life of the patient. Older men (generally those over the age of 70) with slow-growing cancer may very likely die of another condition before the cancer becomes a threat. When all signs indicate the cancer is slowgrowing, the selected course of action may be to wait for symptoms to appear before beginning treatment. It is important in certain cases to weigh the inconvenience of treatment with the risk posed by the cancer.
Generally treatment for prostate cancer may lead to some degree of sexual dysfunction (which is usually treatable); however, libido and orgasms are preserved unless hormone therapy is given. Urinary incontinence is infrequent and is usually due to surgery. Radiation therapy may lead to rectal and bladder irritation. Hormone therapy generally leads to loss of libido and sexual problems as well as hot flashes.
When PSA rises after treatment of any kind, this usually indicates the cancer has come back. Unfortunately no treatment can guarantee a cure. Depending on how aggressive the cancer was at the time of diagnosis, the risk the cancer will recur will vary. PSA testing allows the doctor to detect the recurrence of prostate cancer early and may allow for additional treatment to control the disease before it has spread to other organs.
Yes. There is hope, even at the latest stage of prostate cancer. Even though cure is not possible, with hormone therapy patients may live several years with a very good quality of life. Research continues to improve patients’ life expectancy and quality of life.
This has been the biggest area of research over the last 10 years, and many new treatments have become available that have helped prolong men’s lives and quality of life. Chemotherapy and therapy to help strengthen bones are available, and we are seeing the emergence of other new treatments that are keeping patients alive and well longer. Many new and exciting treatments are still under investigation.
Yes. If the cancer is caught early, remains confined to the prostate and is treated in a timely manner, it can generally be cured.
Because of our northern latitude, the sun’s rays are weaker in the fall and winter. We therefore recommend that Canadian adults consider taking a vitamin D supplement. Talk to your doctor about taking 1000 international units (IU) a day during fall and winter months.
Research enables us to improve the way we treat cancer. Our understanding of cancer and all the new treatments we now have are due to research that involved men with prostate cancer. By participating in a clinical trial, you could have access to new therapies. It involves close follow-up to determine how effective the new treatment is compared to the standard (if any exists) and to identify the side effects. In the vast majority of cases, the advantages of being part of a clinical trial are much greater than the disadvantages. Patients who are interested should always ask their doctor about any ongoing studies that may be of benefit to them.
Research enables us to improve the way we treat cancer. Our understanding of cancer and all the new treatments we now have are due to research that involved men with prostate cancer. By participating in a clinical trial, you could have access to new therapies. It involves close follow-up to determine how effective the new treatment is compared to the standard (if any exists) and to identify the side effects. In the vast majority of cases, the advantages of being part of a clinical trial are much greater than the disadvantages. Patients who are interested should always ask their doctor about any ongoing studies that may be of benefit to them.