Authors: Dr. Colin Michie; Dr. Elizabeth dos Santos, Medical Oncology, British Virgin Islands; Dr. Carel Rikken, Urological Surgeon, St. Martin.
Dr. Colin Michie has worked as a paediatrician in the United Kingdom, Africa, the Caribbean and the Middle East. He is specialised in nutrition, haematology and infectious diseases. Now the Associate Academic Dean for the American University of the Caribbean Medical School in St. Maarten, his enthusiasm is training medical students and healthcare teams to ensure they deliver better value health care.
Sperm and swimming
It is tough being a sperm – so much swimming, so much competition, and just one aim: get to the egg – a simple life. Half of the sperm will give rise to female babies, most will produce right-handed humans and one or two will give rise to St. Martiners with bandy legs.
Sperm are champion swimmers. Splashing around in Mullet Bay is fine for a whole human, but for sperm a twentieth of a millimetre long, the work of moving is much greater. Their tail rotates like a corkscrew three or four times a second so they can cover 1-4 millimetres a minute. This is much more efficient than whole humans doing crawl or even butterfly. Quite a few sperm do not swim too straight either, so only a few will get out front to cover the 18 centimetres to where the egg is likely to be. Human sperm are faster than those of a gorilla, but sperm from those green monkeys in Iguana Bay probably swim twice as fast. A helpful enzyme keeps semen liquid and breaks down mucus in the uterus too. It is called prostate specific antigen (PSA).
Sperm do not do gym. There is a period of waiting, followed by a single race. It takes 72 days to make a human sperm in the testicles. Over the course of a man’s life, he can manufacture up to 12 trillion of them. Once released, sperm can swim for up to five days in the uterus. The sperm engine uses the fruit sugar fructose, rather than glucose. This unusual fuel is supplied mostly from the seminal vesicles (about 75%) as well as the prostate (about 25%). This is the frontline of a dedicated human resources team, designed to start a pregnancy, keeping the species in business!
The prostate gland – is it your hidden enemy?
The prostate gland is not required for life. Like wisdom teeth, the coccyx, extra nipples or the hymen, we can do without it. It is the size of a small guava; it is a spongy glandular tissue. It sits under the bladder, wrapped around the urethra and in front of the rectum. After puberty, the prostate produces some seminal fluid, squeezed out by pelvic floor muscles during orgasm.
About a third of men never experience problems with their prostate. A number of men will suffer as the gland becomes enlarged later in life. It can compress the urethra making the bladder work harder causing frequent urination, particularly at night, and a slower urine flow. Prostate gland enlargement is mostly caused by non-malignant cells.
Cancer in the prostate is the most common cancer diagnosis made in men in the USA and the Caribbean. The rates of this cancer are considerably higher in this part of the world. It is a common cause of death from cancer in older men. Out of 100 men, 13 are likely to develop it and two-three die from it. Prostate cancers mostly grow slowly and often do not cause symptoms when they are small. Fewer than 10% of men with prostate cancer die within five years of diagnosis. Good, safe treatments are available if an early diagnosis is made.
Who needs a prostate check?
Those most likely to develop this cancer are older, of Caribbean descent, with a history of prostate cancer in their father, son or brother. Developing more aggressive cancers at a younger age is a feature more commonly seen in African American populations. For these reasons, it is important to check your prostate if you are over 45 years of age. It may be that you have nothing to worry about. Having a discussion with your doctor, who can help you decide, is important! You may think this unnecessary, or you may imagine the worst outcome, but having a medical check is an important decision to make for your health.
Medical checks carried out by doctors consist of three parts. First, a history to assess your personal risks; then a physical check of the prostate with a rectal examination to examine its size and shape; and finally, a blood test may be ordered for prostatic specific antigen, the enzyme made by the prostate. Levels of this in the circulation are an important factor that helps determine if there is a cancer present. Men usually find this subject embarrassing and difficult, just as do women with cervical screening. As communities around the world, we need to recognise this hurdle and overcome barriers relating to the functions of our sex organs. More discussion is useful!
If a cancer is suspected, imaging of the prostate with ultrasound and sometimes an MRI can be helpful. Early stages of prostate cancer cannot be detected on a physical examination; if there is something unusual on the physical examination, biopsies of the prostate can be performed. If cancer is found, it is possible to perform radiation treatments, surgery, or both. These are best performed by experts in this type of problem as biopsies and treatments can be complicated. It is important to decide if any of these invasive procedures are needed. As with other malignancies, specific treatments are available to destroy cancerous cells with chemotherapy, immunotherapy or hormonal therapy if any of these is needed.
Reduce your risks of prostate cancer to yourself, or your family
Do you want to reduce your risk of prostate cancer? There is good advice from Caribbean research. Start with a check-up. Do not smoke tobacco. Exercise regularly and adopt a healthy diet with less meat, particularly red or processed meats and animal fat. More vegetables and fruits are beneficial. Each of these changes has a protective effect against many cancers. Another less discussed strategy, likely to be prostate protective to some extent, is to increase the number of your ejaculations. Several studies including one which followed men over many years showed that those who had more ejaculations each week, in the absence of risky sexual behaviours, had a lower risk of developing some prostate cancers.
Last month, the causes of delays in finding prostate cancer in men from Trinidad and Tobago were published. Patients there all needed more information about prostate cancer. They tended to talk with pharmacists and traditional healers rather than doctors about sexual problems. Their fears of being examined were found to be a powerful reason for avoiding medical consultation. Avoiding medical screening and early diagnosis created a community burden as well as distress and greater hardship for the men themselves, those that cared for or those that worked with them. Supports from families, church groups and communities are strong on this island. Within these groups, more discussion is needed about taboos related to prostate cancer. When do we remove this fig leaf and make a change in St. Martin?
Immune cells can be used to fight your prostate cancer!
Amazing treatments are being developed to manage prostate cancer. These show how modern science can redirect immune cells to improve health in those with this disease. This will provide hope for a better future for those with this condition.
Cancer cells multiply without the usual controls, which make them grow and spread differently. Cancers challenge the immune system which normally has ways to get rid of them. The reason many cancers grow and cause illness is that they dupe immune cells into protecting rather than attacking them. So to improve cancer treatments, it can be of value to kick the immune system back into action.
An early “immune” treatment was reported in 2005 as being effective in patients with prostate cancer. This approach was approved in 2010 because of its obvious advantages in some groups of patients. The same approach is now being tested in other cancers including skin and breast cancer.
For this early immune treatment, a patient’s white cells are collected (a little like collecting blood for a transfusion). Some of the white cells are then “excited” to attack a marker found on prostate cancer cells. This stimulation is organised in a laboratory. The activated cells are then put back into the patient. The stimulated cells attack the prostate cancer, whether they are in the prostate gland or if they have spread as a metastasis somewhere else in the patient’s body.
Other immune-type treatments
Because they often have fewer side effects than other treatments, immunological treatments of several types have been tested in patients with prostate cancer. For instance, vaccines have been designed to direct specific immune attacks on malignant prostate cells. One vaccine contains two types of virus to enhance immune attackers. Another contains molecules of prostate cancer on carrier cells to encourage more immune cells to destroy malignant cells.
Some specific proteins – antibodies – can be used to manipulate the immune system safely too. They can be designed to block immune cells that protect cancers. Other antibodies can be used to interfere with the protection processes – these have been referred to as “checkpoint” treatments. Trials are in progress in which antibodies are combined with vaccines to maximise the strengths of each in helping patients. The take-home message is that scientists are not sleeping on this problem. The powers of the immune system can sometimes be developed to help fight cancers.
