BACKGROUND
Prostate cancer happens when normal cells in the prostate gland change into abnormal cells and grow out of control. The prostate gland makes some of the fluid that is part of semen. This gland sits below the bladder and in front of the rectum, and forms a ring around the urethra, the tube that carries urine out of the body
DISEASE OCCURRENCE IN POPULATION
Prostate cancer is the second most common cancer in men worldwide, with over 1.2 million cases and 358,000 deaths annually, according to data from the World Health Organization (WHO) GLOBOCAN database. A man’s life time risk of this disease is one out of seven. Internationally, the incidence of prostate cancer varies by more than 50-fold, with the highest rates being in North America, Australia, and northern and central Europe and the lowest rates being in southeastern and south-central Asia and northern Africa.
During 1998-2002, prostate cancer was the fourth common malignancy among males in Karachi (Pakistan) with an age standardized incidence rate was 10.1 per 100,000 men whereas mean age of the cases were 67.4 years. According to another report, estimated incidence of prostate cancer in 2012 is 3,014 with mortality rate of 2,356.
RISK FACTORS
- Age: Prostate cancer is very rare in men younger than 40, but the chance of having prostate cancer rises rapidly after age 50. About 6 in 10 cases of prostate cancer are found in men over the age of 65.
- Race / ethnicity: Prostate cancer occurs more often in African-American men and in Caribbean men of African ancestry than in men of other races. African-American men are also more than twice as likely to die of prostate cancer as white men.
- Family history: If men in your family have had prostate cancer, your risk may be increased. Also, if you have a family history of genes that increase the risk of breast cancer (BRCA1 or BRCA2) or a very strong family history of breast cancer, your risk of prostate cancer may be higher.
- Obesity: Obese men diagnosed with prostate cancer may be more likely to have advanced disease that’s more difficult to treat.
- Smoking: Most studies have not found a link between smoking and prostate cancer risk. Some research has linked smoking to a possible small increase in the risk of death from prostate cancer, but this finding will need to be confirmed by other studies.
- Workplace exposure: There is some evidence that firefighters are exposed to substances (toxic combustion products) that may increase their risk of prostate cancer.
- Inflammation of the prostate: Some studies have suggested that prostatitis (inflammation of the prostate gland) may be linked to an increased risk of prostate cancer, but other studies have not found such a link. Inflammation is often seen in samples of prostate tissue that also contain cancer. The link between the two is not yet clear, but this is an active area of research.
- Vasectomy: Some studies have suggested that men who have had a vasectomy (minor surgery to make men infertile) have a slightly increased risk for prostate cancer. But other studies have not found an increased risk among men who have had this operation. Research on this possible link is still under way.
SIGN AND SYMPTOMS
Prostate cancer often causes no symptoms at first. But if symptoms do occur, they can include:
- Needing to urinate more often than usual
- A urine stream that is slower than usual
- Trouble having an erection
- Blood in the urine or semen
These symptoms can also be caused by conditions that are not prostate cancer. But if you have these symptoms, you should let your doctor or nurse know.
DIGNOSTIC TESTS
Doctors use a blood test called a Prostate specific antigen (PSA) test and an exam called a rectal exam to check for prostate cancer. In a rectal exam, your doctor puts a finger in your anus and up into your rectum. He presses on the rectum wall to feel for abnormal areas on the prostate.
If your doctor suspects you have prostate cancer, he will follow up with one or more tests. These can include:
- Biopsy: A doctor will take a small sample of tissue from the prostate. Then another doctor will look at the sample under a microscope to see if it has cancer.
Ultrasound, MRI scans, or other imaging tests: These tests create images of the inside of the body and can show abnormal growths.
TREATMENT OPTIONS
Your prostate cancer treatment options depend on several factors, such as how fast your cancer is growing, how much it has spread and your overall health, as well as the potential benefits or side effects of the treatment.
Immediate treatment may not be necessary
For men diagnosed with low-risk prostate cancer, treatment may not be necessary right away. Some men may never need treatment. Instead, doctors sometimes recommend active surveillance.
In active surveillance, regular follow-up blood tests, rectal exams and possibly biopsies may be performed to monitor progression of your cancer. If tests show your cancer is progressing, you may opt for a prostate cancer treatment such as surgery or radiation.
Surgery to remove the prostate
Surgery for prostate cancer involves removing the prostate gland (radical prostatectomy), some surrounding tissue and a few lymph nodes. Radical prostatectomy can be performed in several ways:
- Using a robot to assist with surgery: During robot-assisted surgery, the instruments are attached to a mechanical device (robot) and inserted into your abdomen through several small incisions. The surgeon sits at a console and uses hand controls to guide the robot to move the instruments. Robotic prostatectomy may allow the surgeon to make more-precise movements with surgical tools than is possible with traditional minimally invasive surgery.
- Making an incision in your abdomen: During retropubic surgery, the prostate gland is taken out through an incision in your lower abdomen.
Radiation therapy
Radiation therapy uses high-powered energy to kill cancer cells. Prostate cancer radiation therapy can be delivered in two ways:
- Radiation that comes from outside of your body (external beam radiation): During external beam radiation therapy, you lie on a table while a machine moves around your body, directing high-powered energy beams, such as X-rays or protons, to your prostate cancer. You typically undergo external beam radiation treatments five days a week for several weeks.
- Radiation placed inside your body (brachytherapy): Brachytherapy involves placing many rice-sized radioactive seeds in your prostate tissue. The radioactive seeds deliver a low dose of radiation over a long period of time. Your doctor implants the radioactive seeds in your prostate using a needle guided by ultrasound images. The implanted seeds eventually stop emitting radiation and don’t need to be removed.
Hormone therapy
Hormone therapy is treatment to stop your body from producing the male hormone testosterone. Prostate cancer cells rely on testosterone to help them grow. Cutting off the supply of testosterone may cause cancer cells to die or to grow more slowly.
Hormone therapy options include:
- Medications that stop your body from producing testosterone: Medications known as luteinizing hormone-releasing hormone (LH-RH) agonists prevent the testicles from receiving messages to make testosterone.
- Medications that block testosterone from reaching cancer cells: Medications known as anti-androgens prevent testosterone from reaching your cancer cells.
- Surgery to remove the testicles (orchiectomy): Removing your testicles reduces testosterone levels in your body.
Hormone therapy is used in men with advanced prostate cancer to shrink the cancer and slow the growth of tumors. In men with early-stage prostate cancer, hormone therapy may be used to shrink tumors before radiation therapy, which can increase the likelihood that radiation therapy will be successful.
Freezing prostate tissue
Cryosurgery or cryoablation involves freezing tissue to kill cancer cells.
During cryosurgery for prostate cancer, small needles are inserted in the prostate using ultrasound images as guidance. A very cold gas is placed in the needles, which causes the surrounding tissue to freeze. A second gas is then placed in the needles to reheat the tissue. The cycles of freezing and thawing kill the cancer cells and some surrounding healthy tissue.
Initial attempts to use cryosurgery for prostate cancer resulted in high complication rates and unacceptable side effects. However, newer technologies have lowered complication rates, improved cancer control and made the procedure easier to tolerate. Cryosurgery is more frequently used as a salvage therapy for men who haven’t been helped by radiation therapy.
Chemotherapy
Chemotherapy uses drugs to kill rapidly growing cells, including cancer cells. Chemotherapy can be administered through a vein in your arm, in pill form or both.
Chemotherapy may be a treatment option for men with prostate cancer that has spread to remote body locations. Chemotherapy may also be an option for cancers that don’t respond to hormone therapy.
Biological therapy
Biological therapy (immunotherapy) uses your body’s immune system to fight cancer cells. One type of biological therapy called sipuleucel-T has been developed to treat advanced, recurrent prostate cancer.
This treatment takes some of your own immune cells, genetically engineers them in a laboratory to fight prostate cancer, then injects the cells back into your body through a vein. Some men do respond to this therapy with some improvement in their cancer, but the treatment is very expensive and requires multiple treatments.
PRECAUTIONS
You can reduce your risk of prostate cancer if you:
- Choose a healthy diet full of fruits and vegetables: Avoid high-fat foods and instead focus on choosing a variety of fruits, vegetables and whole grains. Fruits and vegetables contain many vitamins and nutrients that can contribute to your health. Whether you can prevent prostate cancer through diet has yet to be conclusively proved. But eating a healthy diet with a variety of fruits and vegetables can improve your overall health.
- Choose healthy foods over supplements: No studies have shown that supplements play a role in reducing your risk of prostate cancer. Instead, choose foods that are rich in vitamins and minerals so that you can maintain healthy levels of vitamins in your body.
- Exercise most days of the week: Exercise improves your overall health, helps you maintain your weight and improves your mood. There is some evidence that men who don’t exercise have higher PSA levels, while men who exercise may have a lower risk of prostate cancer. Try to exercise most days of the week. If you’re new to exercise, start slow and work your way up to more exercise time each day.
- Maintain a healthy weight: If your current weight is healthy, work to maintain it by exercising most days of the week. If you need to lose weight, add more exercise and reduce the number of calories you eat each day. Ask your doctor for help creating a plan for healthy weight loss.
- Food safety precautions for people with prostate cancer: Infection is a concern for people living with cancer, especially during times when the immune system is weak. Handling and storing food safely is an important precaution to reduce exposure to unsafe germs and bacteria.
Food safety tips:
- Wash hands before eating or preparing foods.
- Wash vegetables and fruits.
- Standard guidelines recommend keeping foods colder than 41°F and hotter than 140°F.
Keep raw meats and meat juices away from other foods.
REFERENCES
- Siegel RL, Miller KD, Jemal A. Cancer statistics, 2019. CA Cancer J Clin 2019; 69:7.
- American Cancer Society. Cancer Facts & Figures 2018. Available at https://www.cancer.org/content/dam/cancer-org/research/cancer-facts-and-statistics/annual-cancer-facts-and-figures/2018/cancer-facts-and-figures-2018.pdf. Accessed: February 16, 2018.
- Siegel R, Ma J, Zou Z, Jemal A. Cancer statistics. CA: Cancer J Clin 2015; 65: 5-29.
- Bhurgri Y, Kayani N, Pervez S, Ahmed R, Tahir I, Afif M, et al. Incidence and trends of prostate cancer in Karachi South, 1995- 2002. Asian Pac J Cancer Prev 2009; 10: 45-8.
- Pakzad R, Mohammadian-Hafshejani A, Ghoncheh M, Pakzad I, Salehiniya H. The incidence and mortality of prostate cancer and its relationship with development in Asia. Prostate international. 2015 Dec 1;3(4):135-40.
- http://www.uptodate.com/contents/prostate-cancer-the-basics?source=search_result&search=PROSTATE+cancer+patient+information&selectedTitle=1~150
- http://www.mayoclinic.org/diseases-conditions/prostate-cancer/basics/tests-diagnosis/con-20029597