The prostate is a walnut-sized gland located between the bladder and the penis that serves a role in sexual reproduction. A malignancy or cancer is a disease where cells in the body grow out of control. A malignancy that develops from the tissues of the prostate gland is known as prostate cancer and is one of the most common cancers and cause of death among men worldwide. Factors that put males at risk of developing this cancer are age (>55-69 years of age), genetics (a family history of prostate cancer) and race (African ancestry). What makes this cancer a silent killer is that, many men with it may never develop symptoms until advanced disease has set in. The epidemiology of prostate cancer in the population of Trinidad and Tobago (T&T), with its diversity in ancestral groups, has not yet been described. However, based on case reports, the mortality rate is presumed to be one of the highest in the world. This would indicate a high incidence and prevalence of prostate cancer in T&T, putting a large number of Trinbagonian males within a high risk group for prostate cancer. Being a high risk group of such a fatal disease that often is symptomless, would mean that screening for this disease is essential to diagnose it at an early stage so that prompt, effective and appropriate treatment can be instituted to prevent it being a cause of death (by spreading).
Screening is looking for the presence of disease before it causes symptoms. Within the context of prostate cancer, the goal of screening is to find it at this early localised stage when it is symptomless and may be of high risk of spreading if not treated. Screening for prostate cancer begins with a Digital Rectal Exam (DRE) and a blood test called a Prostate Specific Antigen test (PSA test). A DRE involves your doctor passing his index finger into the back passage and feeling the size and consistency of the prostate gland. In the presence of prostate cancer the gland may be asymmetrical in shape and hard and can help your doctor identify more severe lesions if present. PSA is a substance made by the prostate and is what is tested for in the PSA test. Blood PSA levels are elevated above normal values in conditions that affect the prostate, especially when prostate cancer is present. As a general rule, the higher the PSA blood level, the more likely a prostate problem is present. An elevated PSA level is not specific for the presence of prostate cancer only, however, may also indicate a prostate infection or an enlarged prostate (Benign Prostate Hyperplasia). It may even result from using certain medications or after certain medical procedures like a prostate exam. Also, there is the possibility that the test could give a false positive of an elevated PSA. As many factors result in an elevated PSA, your doctor would need to rule these out before going to the next step of a prostate biopsy or further investigations to rule out a diagnosis of prostate cancer as the cause of your elevated PSA.
The benefit of screening for prostate cancer with the PSA test is that prostate cancer, that may be at high risk of spreading, may be found and treated before it spreads. Thus, the chance of death from prostate cancer in some men is lowered. However, a false positive test can result in a battery of unnecessary tests, like a prostate biopsy, which may cause unnecessary worry about one's health. Men in the age range of 55-69, especially with a family history of prostate cancer and of African ancestry, should make an individual decision of being screened for prostate cancer with a DRE and PSA test. Before making that decision, they should be informed by discussing with their doctor the potential benefits and risks of screening for prostate cancer.
Men who are 70 years or older should not be routinely screened for prostate cancer. If it is present in this age group, it is so slow growing that death will likely be from another cause and instituting treatment may not improve the outcome and likely to cause more distress to the patient. However, this should not be a deterrent to seeking your doctor's advice (if you have symptoms that should concern you).
As a man ages, the prostate tends to increase in size, and because of its location, this narrows the urethra resulting in decreased urine flow. This is known as Benign Prostate Hyperplasia (BPH as mentioned above) - also another cause for a rise in PSA. In prostate cancer a similar situation may arise that may lead to the following symptoms:
o Difficulty starting urination.
o Weak or interrupted flow of urine.
o Frequent urination, especially at night.
o Difficulty emptying the bladder completely.
o Pain or burning during urination.
o Blood in the urine or semen.
o Pain in the back, hips, or pelvis that does not go away.
o Painful ejaculation.
However, different people have different symptoms with prostate cancer, and remember, as mentioned above, it often has no symptoms. Thus, screening is essential in the absence of symptoms, especially if you fall within a high risk group as defined by the risk factors mentioned above. If however, you do have symptoms that worry you, a visit to your doctor is recommended. Keep in mind that these symptoms may be due to a prostate condition other than prostate cancer.
If your PSA level is found to be higher than the normal range for your age and your doctor has ruled out other causes for an elevated PSA, he may then proceed to ruling out the diagnosis of prostate cancer by asking for a prostate biopsy. A biopsy is when a small piece of prostate tissue is obtained and looked at under the microscope for cancer cells. It can also indicate via a special score the likelihood of the cancer spreading if it is present. It is the main tool for diagnosing prostate cancer. However, to ensure the biopsy is made in the right place and cancer is not missed, your doctor may employ other techniques such as ultrasound or Magnetic Resonance Imaging (MRI) to guide in taking the biopsy.
If cancer is diagnosed, other tests may be needed to determine if there is spread. This is called staging and is necessary to determine what treatment needs to be instituted. There are different modalities of treatment of prostate cancer depending on the stage. These range from conservatively monitoring, surgery, radiotherapy, chemotherapy and hormone therapy. Details of these are beyond the scope of this article and may be explored in following articles.
Not everyone needs to be screened for prostate cancer, but those who fall into the high risk group as defined by age (55-69), a family history of prostate cancer and of African ancestry, need to make an informed decision whether to be screened or not after discussing with their doctor. Once the decision is made, DRE and PSA tests are done. If both are negative then screening can be repeated in two years. If the DRE is negative and the PSA elevated or the DRE is abnormal regardless of the PSA value, further evaluation will be required to make the diagnosis and treat.
As an informed population we are better equipped for the fight against cancer. Let us do our part to win the war.