Prostate Cancer

Prostate cancer grows slowly and there are usually no obvious warning signs in the early stages of the disease, so the patient may not be aware of the tumour even if it has been in the body for many years. However, when the tumour grows bigger or starts to spread to other parts of the body, the patient may experience the following symptoms:

• Frequent urination, especially at night
• Difficulty passing urine
• Redness and pain when urinating or ejaculating
• Blood in the urine or semen
• Leakage of urine even after urination

In addition, if the cancer has spread to the bones, spine or pelvis, the patient may feel stiffness or pain, fatigue, loss of appetite and weight loss.

However, in addition to prostate cancer, an enlarged prostate gland will also show similar symptoms, so if you notice any of the above, you should have it checked as soon as possible.

The prostate gland is part of the male reproductive system and is located between the neck of the bladder [Note 1] and the urethra, and is similar in shape to a walnut. The prostate gland secretes a white fluid that mixes with sperm to form semen. 

Generally speaking, older men often have enlarged prostate glands, most of which are benign. However, if there is a genetic mutation in the cells and they become a malignant tumour, it is called prostate cancer.

The distribution of prostate cancer patients is affected by different risk factors. Most of the patients mentioned above are over 65 years old, which is the most important factor, and the following conditions are also involved:

• Family history of prostate cancer in men, e.g. father, elder brother, etc.
• Consumption of high calorie and high fat foods over a long period of time.
• Lack of exercise over a long period of time
• Smoking habit
• A history of prostate cancer

Based on the above risk factors, to prevent prostate cancer, it is important to develop a good diet and consume more high-fibre and low-fat foods, such as soy products, fresh fruits and vegetables, to prevent or delay the formation of prostate cancer.

If prostate cancer is detected late and not treated in time, there is a chance that the disease may worsen. One scenario is that the cancer cells may metastasize to other parts of the body, for example, to nearby lymph glands through lymphatic vessels, or to the discs, lumbar vertebrae, femur and ribs, where the patient may experience more severe pain.

The cancer may also spread to the lungs, pleura, liver, kidneys, adrenal glands, and brain.

If you notice symptoms of suspected prostate cancer, you should seek medical advice as soon as possible and undergo an in-depth examination. The doctor will perform all or some of the following tests:

• Anal examination
• Blood test
• Ultrasound
• Biopsy
• Urological endoscopy

If prostate cancer is diagnosed after these tests, the doctor may need to perform more in-depth tests:

• Bone X-rays or scans
• Ultrasound, CT or MRI of the abdomen
• Lung X-ray

Once the doctor has a good understanding of the patient's condition through these tests, he or she will decide on the treatment to be used. As prostate cancer tumors grow slowly and may not be life-threatening, and as most of the patients are older, doctors will take into account additional factors including the patient's health status, the extent of the tumor's impact, and the level and rate of increase of prostate-specific antigen (PSA) in the blood serum.

In addition, the Gleason score can be used to determine which treatment is more appropriate for the patient based on the rate of growth and risk of spread of the tumour, the higher the Gleason score, the higher the risk of prostate cancer, which is categorized as follows:

• Low risk

If the cancer has invaded no more than half of the prostate, and the serum prostate-specific antigen index is less than 10 ng/mL, the Gleason score is less than 7.

• Intermediate risk

A tumour that would not be classified as high or low risk.

• High risk

Cancer has begun to invade the peripheral tissues of the prostate, with a serum prostate-specific antigen index greater than 20 ng/mL and a Gleason score greater than 7.

There are four types of treatment for prostate cancer:

• Active surveillance
• Radical prostatectomy
• Caesarean section

Surgery is performed through a long incision from the umbilicus to the pubic bone.

• Minimally invasive surgery

A few small incisions are made and a special instrument is inserted into the body to remove the prostate while the surgeon observes the operation through a screen, which reduces the patient's pain.

• Robotic Surgery

A robotic arm is operated by the surgeon to perform minimally invasive surgery through several small incisions. The robotic device provides better visualisation, including stereoscopic, high-definition and 10x magnification functions, and can be flexibly manipulated with greater accuracy.

Patients may experience incontinence after prostatectomy. About 15% of patients over 70 years of age will have persistent incontinence, while less than half of patients under 50 years of age will have permanent incontinence. It is also quite common for patients to experience erectile dysfunction after prostatectomy, as the tissue responsible for erectile control may be touched or removed during the procedure. However, many patients are able to maintain a sex life with oral medications, vacuum erection devices [Note 3] or sponge injections into the penis.

• Radiotherapy
• Commonly known as "electrotherapy", it can be divided into two forms: external and internal:
• External

It is suitable for patients with various risks. The procedure is similar to an X-ray, in which the patient lies on a machine that uses high-energy rays to destroy cancer cells in the patient's body and prevent them from dividing. Generally speaking, the procedure lasts for about 7.5 weeks and is performed five times a week, each time taking about 20 to 30 minutes. There is no need for anaesthesia or surgery, and the patient does not need to be hospitalised. However, as the rectum is close to the prostate gland, it is exposed to high doses of radiation, which may result in minor bleeding or ulceration in the future.

• In Vivo

The procedure is only suitable for low to medium risk prostate cancer. Surgery involves implanting multiple radioactive metal pellets into the prostate gland for brachytherapy. The radiation level of these metal pellets will gradually decrease and there is no need to remove them again. Although the time required for the intracorporeal radiotherapy procedure is short, the radiation does not cover the tissues in the vicinity of the gland. It is not common in Hong Kong and clinical experience is scarce.

• Hormonal Therapy

Hormonal therapy can be used as an adjuvant to radiotherapy to eradicate higher risk tumours, or to relieve advanced prostate cancer that has spread to other parts of the body. It is also the only treatment that is suitable for patients who are too old and frail to undergo surgery or radiotherapy. Simply put, this treatment involves interfering with male hormones to cause the prostate tumour to shrink, and the most direct and long-lasting way to do this is to remove the testicle. The most direct and long-lasting way is to remove the testicles. Alternatively, patients may choose to have an injection every three months that interferes with the pituitary gland's endocrine secretion, indirectly suppressing testicular production of testosterone. However, no matter which method of hormone therapy is used, the suppression of testosterone itself will lead to various side effects, including fatigue, osteoporosis, increase in blood glucose and blood lipids, increase in body weight, etc. Some patients may even suffer from loss of libido, impotence, and muscle atrophy.

After treatment, patients should continue to pay attention to their diet, especially reducing the intake of fat, and should do a moderate amount of exercise every day to maintain a good physical condition, which will help strengthen the immune system and reduce the chance of recurrence. Patients who are obese should lose weight to protect their heart. In terms of sex life, some patients may face impotence, and may switch to embracing and stroking to maintain sexual contact with their partners.

Note 1: The bladder neck is a tubular structure that extends 1 to 2 centimetres from the urethral opening into the urethra.

Note 2: Prostate Specific Antigen (PSA) is a glycoprotein synthesized and secreted by the epithelial cells of the prostate gland.

Note 3: A vacuum erection device is a cone that fits over the penis with a pump that is placed at the base of the penis to pump out air, creating a vacuum that allows blood to flow into the sponge, causing the penis to become erect.

1. [Prostate Cancer Treatment] Symptoms, Causes and Treatment ｜Heal Oncology Centre from https://heal-oncology.com/cancer/prostate-cancer/
2. Smart Patient Website - Prostate Cancer｜Hospital Authority from https://www21.ha.org.hk/smartpatient/SPW/zh-hk/Disease-Information/Disease/?guid=788c2a62-d583-4ad1-b124-a7209d0ec8e5
3. Prostate Cancer｜Prostate Cancer Support Service in Hong Kong｜Cancer Foundation from https://www.cancer-fund.org/prostate-cancer/
4. Hong Kong Anti-Cancer Society from https://www.hkacs.org.hk/tc/knowcancer_detail.php?id=6
5. Prostate cancer - Symptoms and causes｜Mayo Clinic from https://www.mayoclinic.org/diseases-conditions/prostate-cancer/symptoms-causes/syc-20353087