BY: Kwame Sherrif Awiagah (BSc, MPhil)
The month of September is a particular month set aside for awareness creation for many different types of cancer affecting humanity. The month is observed by many international and national organizations promoting a specific kind of cancer awareness. The month is inundated with awareness campaigns, public lectures, seminars, health screening, and public policy advocacy to support some types of cancers. One of such cancers is Prostate cancer. Prostate cancer is primarily a disease of men affecting mostly men aged 40years and above, rarely below 40years. In September, termed the blue month, you are implored to take action against prostate cancer.
Epidemiology of Prostate cancer
The international agency for Research on Cancer (IARC) estimates that one (1) out of every three (3) men aged 40 years and above is at risk of prostate cancer. Prostate cancer is the 2nd most diagnosed cancer worldwide, and the 6th leading cause of cancer deaths among men globally. An estimated 1,276,000 new prostate cancer cases and 359,000 prostate cancer deaths were recorded in 2018 worldwide.
IARC projects that 2.3million new cases and 740,000 deaths from prostate cancer will be recorded globally by 2040. These are estimates generated using mathematical modeling based on the growth and aging of the population.
In developing countries with 10.5 per 100,000 incidences of prostate cancer and where health care is still a challenge, cancers are predicted to be the significant causes of morbidity and mortality by 2040. Quality data on all forms of cancers are challenging to access or unavailable altogether in many African countries due to the absence of National Cancer Registries. Eighty thousand nine hundred seventy-one new prostate cancer cases were recorded in 2018, and 178,634 projected to be recorded in 2040 in Africa.
In Ghana, where prostate cancer incidence is increasing and is the 2nd leading cause of cancer deaths in men, there is no National Cancer Registry for effective data management relating to cancer morbidity and mortality. However, two independently managed cancer registries in Kumasi and Accra are managed by part-time staff (and interns) in Komfo Anokye Teaching Hospital and Korle-Bu Teaching Hospital, respectively.
The Prostate Gland
The prostate gland is a muscular walnut-sized gland that encircles the urethra (a tube that carries urine and semen through the Penis) and ejaculatory duct, located inferior to the urinary bladder, at the base of the Penis, and anterior to the rectum. It measures two by four by 3 cm and weighs about 30g. The prostate gland consists mostly of glandular tissues, connective tissues, and smooth muscles.
The prostate gland produces thin, milky secretion known as the prostatic fluid. This fluid forms 30% of the semen with the primary function to protect, support, and assist in the transport of sperm after ejaculation. Hormones are essential for the functioning of the prostate gland. These are the dihydrotestosterones and testosterones collectively known as androgens (male hormones).
As an organ of the male, the prostate gland is only functional for male reproduction but not a vitality for life. As men advances in age, the gland enlarges, and overtime may lead to one of several prostate conditions known as Benign Prostatic Hyperplasia/Hypertrophy, which presents with an obstruction to urine flow.
Prostate Cancer
Like many cancers, prostate cancer develops when healthy cells of the prostate glands grow and change independently of the regular cell control system resulting in tumor formation. A tumor formed this way can be Benign or Malignant. A Benign tumor will mostly grow slowly and be confined to the prostate gland, unlike a malignant tumor, which can develop gradually or rapidly but with the certainty of spreading to other tissues or organ systems as it advances.
An intriguing feature of prostate cancer is that it grows very slowly and may be confined to the prostate gland (even at its advanced stage) for a long time before spreading to other parts of the body. Of course, aggressive tumors grow much faster and rapidly spread to other parts of the body. Different types of algorithms are used for staging prostate tumors.
The most commonly used are the clinical staging and pathological staging. Clinical staging uses both clinical examinations and laboratory investigations to detect cancer. On the other hand, the pathologic stage is usually done after surgery when tissues of the prostate gland and some lymph nodes are removed. The cancer staging outcome provides a fair idea of the type of tumor, and further laboratory and imaging studies needed.
Know the signs
For many patients with prostate cancer, clinical signs and symptoms mimic those of enlarged prostate gland, prostatitis (inflammation of the prostate gland), other prostate conditions, genitourinary tract infections, and other non-urological conditions. Common among these non-specific symptoms are frequent micturition, painful urination, obstruction to urine flow presenting as urine retention, discomfort or pain during sitting position, new onset of erectile dysfunction, straining during urination, blood in urine, and seminal fluids. Once cancer begins to spread, symptoms will be vaguer and may not be perceived by the patient as symptoms related to the prostate condition. Some of these symptoms include a change in bowel habit, unexplained weight loss, easy fatigue, pain that may be felt in the back, hips, etc., fluid buildup in the leg and pelvic region, and loss of appetite.
How at risk are you?
The etiology of prostate cancer remains the subject of investigations by researchers in urology and oncology. However, well-established prostate cancer risk factors include advanced age, family history, genetic factors, ethnicity, dietary habits, and obesity.
Advanced Age: Prostate cancer risk increases with advanced age, usually after 40years in men with familial history and 50 years in men without a family history. Age remains the most positive risk factor for prostate cancer. Indeed, it has been reported that up to 30% of men aged 50years and above demonstrated histological evidence for prostate cancer having died from causes other than prostate cancer through autopsy report.
Family history and genetic factors: Up to 20% of men diagnosed with prostate cancer have a family history of the disease not related to genetic factors but as a consequence of their association with a common environmental hazard (carcinogenic) and lifestyle factors. Many inheritable genes have also been implicated in prostate cancer risks. Common among them is the “BRCA1 and 2 mutations that showed a clinically aggressive form of prostate cancer “. Again, BRCA2 mutation is also associated with a higher incidence of familial prostate cancer.
Ethnicity: Prostate cancer risks are highest among African American men than their counterpart whites with the lowest prevalence been among American Indians and Asia or pacific islanders. These differences nonetheless correlate with socioeconomic and biological factors that tend to disfavor blacks compared with other racial groups. For instant black men are less likely to go for prostate health screening compared with their white counterparts, and scientists have documented a “significantly higher PSA levels were seen in Black men, with or without prostate cancer when compared to White men” and “African-American men have the more common chromosome 8q24 variants, which are associated with increased prostate cancer risk” Other researchers have demonstrated that “African-American men display a more aggressive form of the disease, which has also been associated with genetic and biologic differences.”
Dietary habits: The role of diet in prostate cancer development has been reported by many researchers who identified an association between some nutritional practices and the risk of prostate cancer development. Saturated animal fat, red meat, calcium, milk, dairy products, and low folate and vitamin B12 have been implicated as dietary products with increased risk of developing prostate cancers. These nutritional products have their respective daily allowances beyond which an association can be established with prostate cancer development.
Lifestyle and environmental carcinogens: Obesity, Smoking, and alcohol abuse are lifestyle factors associated with increased risk for most human cancers, including prostate cancer. An exposure to various environmental carcinogenic agents used in herbicides, including Agent Orange used during Vietnam War as a defoliant and insecticides, has increased the risk for developing prostate cancer even though this can make the progress of cancer much slower compared with other factors.
Diagnosing Prostate cancer.
Diagnosing prostate cancer begins with history taking and Medical Examinations. Based on this, the doctor will prescribe the following to come up with a working diagnosis.
Digital Rectal Examination: this is a test done in the doctor's office or exanimation room. The prostate gland location allows the doctor to assess the prostate gland's structure and texture by inserting a gloved finger in the rectum.
Prostate-Specific Antigen Test (PSA): PSA is an enzyme produced by the prostate gland and circulate in the blood. Though there are no specific levels of circulating PSA in the blood, it increases beyond a certain cancer threshold. Other conditions that may increase PSA levels are BPH, Prostatitis, and shortly after ejaculation.
It is a standard tool for screening prostate cancers in many countries, including Ghana. However, some authorities do not recommend its use, especially in the aged with a life expectancy of less than 10years. A PSA version is the free PSA test, which measures the PSA level that is not bound to protein against the standard PSA test, which measures both bound and unbound PSA in the blood. The free PSA test allows a measure of the ratio of free PSA to PSA through which doctors can tell if an elevated PSA level is due to Malignant tumors.
Biomarkers: This test measures specific substances produced by malignant tumors or by the body in response to the tumors and expressed in blood, urine, or body tissues. While research is still ongoing to develop more effective biomarkers for prostate cancer, some useful biomarkers are used to diagnose or screen for prostate cancer risks, including Prostate Health Index, 4Kscore, Decipher, Prolaris, ProMark, and Oncotype Dx Prostate.
Biopsy for Histopathology: This procedure involves taking tissues from the prostate gland through a surgical procedure; the tissue is then prepared and visualized under a microscope that allows the pathologist to tell if the tissues are malignant, same time grade the tumor cells.
Other diagnostic procedures include imagery and blood works that may not be specific for prostate cancer, are carried out to make an informed decision on treatment and/or management options.
Treatment options available.
The decision and plan for individual prostate cancer management depend on many individual factors, including the type and stage of cancer, patient’s age, presence of co-morbidities, the patient’s informed treatment preference, and overall health status of the patient.
For most patients, active surveillance and watchful waiting are all that is required. Patients on active management undergo scheduled testing to ensure that cancer does not progress or spread to other parts of the body. This allows the team to intervene early enough as it becomes necessary while avoiding the side effects associated with some treatments.
Patients on watchful waiting may not benefit from scheduled testing and usually recommended for patients with less than 5years of life expectancy. This group of patients is followed up for the discomfort and addressed accordingly.
Surgery, Chemotherapy, Radiation therapy, and Hormonal therapies are different treatment options available to patients and the multi-disciplinary team members to choose based on recommended guidelines.
You can reduce your risk factor (s)
“Although the data about the role of specific lifestyle factors fostering prostate cancer development have often been conflicting, most of the studies evidence a diet rich in fruits, vegetables, and anti-oxidant micronutrients, and poor in saturated fats and “well-done” red meats, may significantly reduce risks of prostate cancer development, as well as the risk of diseases typical of the industrialized world” (World J Oncol. 2019).
Lifestyle modification is a well-researched prostate cancer risk reduction strategy that offers men an opportunity to increase their quality of life even in advanced age. It is the only cancer prevention strategy that has no proven side effects and yet very cost-effective.
Conclusion
Once prostate cancer was thought to be a disease of the industrialized world, the evidence available now contradicts this assertion. Prostate cancer incidence is rapidly decreasing in developed countries while increasing in the developing world.
Preventive measures that also include effective prostate cancer screening is the most proven measure to reduce prostate cancer incidence among the at-risk group. Take the initiative today to discuss with your doctor your prostate cancer risk and how to prevent or modify it.
References
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About the author
He is a Medical Virologist, Senior Nurse at Korle-Bu Teaching Hospital, and a member of the Medical Journalists’ Association – Ghana and a member of the World Federation of Science Journalists.