In Singapore, prostate cancer is the third most common cancer diagnosed in men. Here is a look at the risk factors, symptoms and treatment options.
Prostate cancer is one of the most common types of cancer in men.
In Singapore, it is the third most frequently diagnosed cancer among men, after colorectal and lung cancers, and accounts for about one in seven cancer diagnoses in men, according to the Singapore Cancer Registry Report 2015. Figures show that Chinese and Indian men are more likely to be hit by prostate cancer than their Malay counterparts.
What is prostate cancer?
Prostate cancer is a tumour that grows in the prostate – a small walnut-sized gland below the bladder which produces seminal fluid. Most prostate cancers are slow-growing and confined to the prostate gland. However, there are also aggressive types which can spread quickly to other parts of the body, especially the bones and lymph nodes. If it is detected early, when the tumour is still confined to the prostate gland, the chance of successful treatment is higher.
Who is at risk?
Risk factors include:
- Age:The risk of prostate cancer increases with age. It usually affects men after the age of 50 and is most commonly seen in men over 70 years old.
- Weight and diet:Men who are overweight or obese, and those who eat excessive amounts of meat or food high in animal fat have a higher risk.
- Family history:Men with family members who have had prostate cancer have a higher risk.
- Sexual activity:Men who start having sex at an early age, and those who have a history of sexually-transmitted diseases or multiple sexual partners, have a higher risk.
What are the symptoms and signs?
In many cases, there are no symptoms; it is believed that as many as 80 per cent of men who reach the age of 80 will have prostate cancer. As most cases of prostate cancer are slow-growing, many men may die of other age-related diseases without ever realising that they have this cancer.
When symptoms do emerge in more advanced stages, they may include weight loss, bone pain, difficulty passing urine, burning sensation or pain during urination, or blood in the urine.
When should I see a doctor?
While it is possible that these symptoms may be caused by something less serious, they could also be a warning sign for prostate cancer. If you have any sign or symptom that worries you, make an appointment to see a doctor so that further tests can be done.
How is the cancer diagnosed and assessed?
Screening tests include:
- Digital rectal examination (DRE):A physical examination in which a doctor will gently insert a gloved, lubricated finger into the anus to feel for any lump or growth in the prostate.
- Prostate-specific antigen (PSA) test:The most common initial test for prostate cancer, this is a blood test that measures the level of PSA, a protein produced by cells in the prostate gland. The higher the PSA level, the more likely that cancer cells are present. However, an elevated PSA reading may also be caused by other factors as well.
Diagnostic tests include:
- Prostate biopsy:If prostate cancer is suspected, a biopsy involving the removal of sample tissue from the prostate is carried out. If the result is positive, a bone scan or computer scanning of the pelvis may be done to determine the extent of the cancer.
- Transrectal ultrasound:Sound waves are used to visualise the prostate gland. This is most often used during a biopsy, to guide the needles into the part of the prostate gland where the tumour is suspected.
If prostate cancer is diagnosed, these tests may be done:
- PSA levels:Measuring PSA levels may help determine the extent of the cancer. PSA levels of over 20ng/mL may be suggestive of higher risk disease.
- Tests for metastasis:If a biopsy indicates cancer, other tests will have to be done to determine how far the cancer has spread. Bone scans and X-rays may reveal whether the cancer has invaded the bones, while computed tomography (CT) or magnetic resonance imaging (MRI) scans can further pinpoint the location of the cancer.
How is prostate cancer treated?
In some cases, because prostate cancer may take many years to progress, doctors may choose to monitor the tumour rather than treat it immediately. This is because treatment depends on factors such as the stage of the cancer, symptoms, age, and general health of the patient. Treatment options include:
- Surgery:If the cancer is localised, the prostate gland may be surgically removed. Chances of a full recovery are high in such cases, but possible side effects include urinary incontinence and impotence.
- Radiation therapy:High-energy rays are used to target and kill cancer cells. This may be used when the cancer is localised, or to control symptoms if the cancer has spread, for example, to the bone.
- Hormonal therapy:When the cancer has spread beyond the prostate, hormonal therapy may be used to counter the effects of testosterone and slow down the growth of the cancer.
- Chemotherapy:Chemotherapy is sometimes used if the prostate cancer has spread outside the prostate gland and hormone therapy is no longer working. Recent research has also shown that chemotherapy might be helpful if given along with hormone therapy..
- Bone-targeted therapy:If the prostate cancer spreads to other parts of the body, it often goes to the bones first. Bone metastases can be painful and can cause other problems, such as fractures or high blood calcium levels. Treatments more specifically targeting bone metastases include bisphosphonates, denosumab and radiopharmaceuticals (drugs that contain radioactive elements).
Prostate cancer: Symptoms & signs
In most cases, prostate cancer may not show any sign or symptom in its early stages. When symptoms do emerge in more advanced stages, they include:
- Pelvic, back or hip pain
- Bone pain that refuses to go away
- Urinary difficulties e.g. burning or painful urination, inability to urinate, or blood in urine
- Blood in semen