Watchful waiting
Sometimes, men are advised to wait to see if they need treatment. This is called watchful waiting. These men have regularly scheduled exams and tests to closely monitor their condition. Many men, especially older men, whose prostate cancer is slow growing and found at an early stage, may not need treatment.
Regular follow-up blood tests, rectal exams and possibly biopsies may be performed to monitor for evidence of progression of your cancer. Watchful waiting may be particularly appropriate if you're elderly, in poor health or both. Many such men will live out their normal life spans without treatment and without the cancer spreading or causing any problems. On the other hand, if a decision is made to treat the cancer, treatment options currently available include:
Surgery
Surgery -- a common treatment in early stages of prostate cancer. Surgery to remove the entire prostate is called radical prostatectomy. During this procedure, the surgeon uses special techniques to completely remove your prostate and local lymph nodes, while trying to spare muscles and nerves that control urination and sexual function. It may optimally treat cancer in its early stages and may help extend life in the later stages, however with possible side effects which may include impotence and urinary incontinence.
Three surgical approaches are available for a prostatectomy, retropubic, perineal and laparoscopic:
Retropubic surgery. In this approach, the gland is taken out through an incision in your lower abdomen that typically runs from just below your navel to an inch above the base of your penis.
Perineal surgery. With the perineal approach, an incision is made between your anus and scrotum. There's generally less bleeding with perineal surgery, and recovery time may be shorter, especially if you're overweight.
Robotic assisted laparoscopic surgery. The advent of robot-assisted laparoscopy signalled a new era in minimally invasive surgery, allowing surgeons to perform complex reconstructive procedures after radical prostatectomy with the benefit of reduced blood loss, less pain and quicker postoperative recovery.
Another type of surgery involves removing part of the prostate called a transurethral resection of the prostate (TURP). In this surgery, part of the prostate that surrounds the urethra is removed. This surgery is usually done on men who cannot have a radical prostatectomy because of other medical problems. It is also sometimes done before starting another kind of treatment. This surgery can relieve symptoms caused by the tumour, but does not cure the cancer because not all of the cancer will be removed with this surgery.
Radiation
In radiation therapy (also called radiotherapy), high-energy x-rays are used to damage and kill cancer cells and stop them from growing and dividing. Like surgery, radiation therapy is local therapy; it can affect cancer cells only in the treated area.
Unlike surgery, which is best used in early stage disease, radiation can be used in all stages of prostate cancer. It can be used as an alternative to surgery in localized disease, or it may be used after surgery to reduce the chance of recurrence when there is a high possibility that there are remaining cells in the area. In disease that has spread, it may be given to relieve pain or other problems.
There are two types of radiation therapy, external and internal.
External beam radiation uses a machine outside of the body to deliver high-energy x-rays beams to the specific area around the tumour. This is usually done on an outpatient basis, five days per week, for about seven weeks. Our very modern machines now have sophisticated technological capabilities such as 3-D Conformal Radiation Therapy and Intensity-Modulated Radiation Therapy.
Treatment is accurately planned and delivered with computer assistance. These advanced techniques allow high doses to deposited conformally around the tumour and adjacent areas which must be treated while reducing exposure to surrounding tissues which do not need to be treated.
Most men have mild side effects from this type of treatment, but most of the side effects resolve shortly after treatment is completed. Most men do not have problems with erections or intercourse immediately after radiation therapy. However, radiation can cause sexual side effects in some men later in life. During treatment some men experience urinary problems.
The most common signs and symptoms are urgency to urinate and frequent urination. These problems usually are temporary and gradually diminish in a few weeks after completing treatment. Long-term problems are uncommon.
Rectal problems such as loose bowel movements, scant rectal bleeding, discomfort during bowel movements and a sense that you have to have a bowel movement (rectal urgency) — may arise during treatment. Once the course of treatment is complete, these symptoms generally subside. However, a few men may continue to experience rectal problems months after treatment, but these improve on their own in most men.
Internal radiation is called brachytherapy. Brachytherapy is done by use of radioactive implants that may be permanent or temporary. Its main advantage over external beam treatment is its ability to deposit a higher dose to the tumour in the area encompassed by the radioactive sources while sparing or subjecting to a lower dose the adjacent normal tissues.
In temporary implants, small pellets of radioactive material on a string are inserted into the prostate. Once they are removed, there is no radioactivity in the body. Permanent implants are small radioactive seeds (pellets) that are inserted into the prostate. The pellets loose their radioactivity over time, which may be weeks or months. This therapy is generally used in men with smaller or moderate-sized prostates with small and lower-grade cancers. Sometimes, hormone therapy is used for a few months to shrink the size of the prostate before seeds are implanted.
Side effects of seed implants are somewhat different from those of external-beam radiation. Seed implants deliver a higher dose of radiation to your urethra causing urinary symptoms such as frequent, slower and painful urination to occur in nearly all men. Medication may be required to treat these symptoms, and some men require medications or the use of intermittent self-catheterisation to help them urinate.
Urinary symptoms tend to be more severe and longer lasting with seed implants than with external-beam radiation. Rectal symptoms, however, may be less frequent and less severe. Some men experience impotence due to radioactive seed implants.
Hormone therapy
This form of treatment prevents the prostate cancer from getting stimulated by the male hormones (androgens), which it needs for growth. It is usually used for prostate cancer that has metastasised. Hormone therapy can make the cancer stop growing or shrink, but it does not cure the cancer. There are several different hormone therapies including the removal of the testicles (orchiectomy), hormonal drugs, or chemicals. One approach uses luteinizing hormone-releasing hormone agonists (LHRH), given as shots (injections) to decrease the amount of testosterone made in the testicles. The female hormone estrogen, taken in pill form, is also sometimes used for this purpose. Other hormones called anti-androgens, given as pills, are used to stop the body from using androgens. Alternative hormones can be used if the initial ones stop working. Hormone therapy is sometimes given along with other types of treatment.
In most men with advanced prostate cancer, this form of treatment is effective in helping to slow the growth of tumours. Because it is effective in shrinking tumours, doctors use hormone therapy in some early-stage cancers in combination with radiation and sometimes with surgery. Hormones shrink large tumours so that surgery or radiation can remove or destroy them more easily. Given after these treatments, the drugs can inhibit the growth of stray cells left behind.
Simply depriving prostate cancer of testosterone does not usually kill all of the cancer cells. Within a few years, the cancer often learns to thrive without testosterone. Once this happens, hormone therapy is less likely to be effective. However, other treatment options still exist.
Side-effects of hormone therapy may include breast enlargement, reduced sex drive, impotence, hot flashes, weight gain and reduction in muscle and bone mass. Some of these drugs can also cause nausea, diarrhoea, fatigue and liver damage.
Chemotherapy
This type of treatment uses chemicals that destroy rapidly growing cells. Chemotherapy can be quite effective in treating prostate cancer, but it cannot cure it. Because it has more side effects than hormone therapy does, chemotherapy is often reserved for men who have hormone-resistant prostate cancer, especially if their cancer is causing symptoms.
Recently, two landmark randomised controlled trials demonstrated for the first time that overall survival for patients with metastatic hormone refractory prostate cancer can be improved with a systemic docetaxel-based combination chemotherapy.
Prevention
The huge difference in prostate cancer incidence rates between Asians and Caucasians have led investigators to compare differences in lifestyle and diet between Asians in their native countries and Asian migrants to high risk countries.
Early epidemiological studies suggested a possible causal association between dietary animal fat and prostate cancer.
Many other dietary factors have been studied with regards to prostate cancer risks and their roles may be summarized into two contributing causes:
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as an influence on circulating androgens or oestrogens |
| 2. |
as a general protective effect against mitogens. Dietary factors that have been cited as a possible contributing factor to the low incidence in Asians include low dietary fat, isoflavonoids in soybeans, polyphenols in green tea, lycopene in cooked tomatoes, Selenium and Vitamin E. |
Therefore, for a healthier diet that may reduce the risk of prostate cancer, we recommend a reduction of intake of red meat, dairy products, saturated fats, and egg yolk, and consumption of plenty of fruits and vegetables each day. The potential of selenium and vitamin E (taken alone or in combination) for preventing prostate cancer is currently being evaluated in a clinical trial.
Weber Lau
Senior Consultant
Dept of Urology
Singapore General Hospital
Terence Tan
Senior Consultant
Radiation Oncology
National Cancer Centre, Singapore
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