Prostate Cancer
What is Prostate Cancer?
Prostate cancer is a malignant tumour of the male prostate gland that is located right below the bladder and envelops the urethra – the tube through which the body removes urine.
It is one of the most common neoplasms and the second cause of cancer deaths in men.
This type of cancer is unusual, as it evolves silently. In most cases, there are no symptoms while the tumour is growing and issues only arise when the disease is at an advanced stage.
The cancer occurs due to abnormalities in the gland cells. In normal situations, the cells grow and divide to form new ones. Some die and are replaced, following what is considered to be the normal lifecycle of a cell. This process changes in the case of cancer.
At a certain moment, and for unknown reasons, cells become more aggressive due to changes in DNA. They start to multiply uncontrollably and more quickly than other prostate cells. Moreover, old and sick cells do not die, accumulating in the organ and leading to the tumour.
Causes of Prostate Cancer
Old age
Men over 50 years of age are in greater risk of developing this disease.
Family history
The risk is higher if a close relative (a father, brother or uncle) has had prostate cancer.
Ethnicity
This tumour is more common in black people.
Testosterone
Degeneration and cell multiplication in the prostate is caused by the male hormone testosterone.In addition to the above, dietary habits also have a major impact.
Diets rich in saturated fat and protein with high red meat consumption can also be a cause.
Obesity and exposure to toxins also seem to enhance the probability of tumours.
Types of Prostate Cancer
Prostate enlargement is not always due to cancer. In some cases, this may be benign. It means the disease is not as aggressive and the probability of the patient’s life being at risk is lower. These patients can be treated with far fewer risks of complications or after effects.
Unlike benign tumours, malignant tumours like prostate cancer can grow locally and invade other close organs or metastasise, i.e. spread and affect other organs far from the original source.
In prostate cancer, these two types of cancer cell behaviour can occur:
- In the absence of early diagnosis, cancerous cells can multiply and spread beyond the prostate to other neighbouring organs.
- It is also possible that cancerous cells free themselves from the tumour, travel via the lymphatic system or bloodstream and cause the formation of “tumours” in other organs (metastases). This process is known as metastisation.
A malignant prostate tumour can comprise various types of cells, but in most cases they are adenocarcinoma. In rarer situations – less than 1% of cases – it may be another type of cancer. Tumours can occur in the prostate like small-cell carcinoma and sarcoma.
Prostate Cancer Symptoms
Prostate cancer is usually asymptomatic for years, evolving without any manifestation.
However, some signs can exist that raise suspicions. The symptoms depend naturally on the stage of the cancer’s evolution.
Early-Stage Symptoms
In cases where the cancer is detected/diagnosed at an early stage, the symptoms manifest themselves due to the localised enlargement of the tumour.
Bear in mind that the symptoms are not exclusive to prostate cancer, i.e. they can also be found in other diseases. It is very important therefore to undergo a differential diagnosis.
In prostate cancer, the symptoms are above all related to the lower urinary tract.
They are split into three categories: bladder filling, bladder emptying and post-urination.
1. Bladder emptying symptoms manifest themselves through:
- Weak and/or thin urine jet;
- Interruption of the jet (not urinating everything in one go);
- Length of time needed to urinate;
- Length of time before starting to urinate;
- Burning sensation when urinating;
- Need for abdominal effort in order to urinate.
2. Bladder filling symptoms include:
- Sudden need to urinate;
- Inability to retain urine when there is a sudden need to urinate;
- Increased frequency of urinating (frequent urinating);
- Increased number of times urinating during the night;
- Pain/sensation of weight below the navel.
3. Post-urination symptoms include:
- Sensation of not emptying the bladder completely;
- Dripping urine after urination.
As the tumour is generally asymptomatic, these symptoms may never occur. They may be seen at locally advanced stages of the disease or when the cancer is associated with a benign enlargement in the prostate’s volume.
Other less typical symptoms may also occur, such as blood in the urine, urinary infections, back pain or, later, acute urine retention (trapped urine, inability to urinate, which can occur suddenly).
As the cancer evolves, patients experience another type of symptoms.
Metastasized Cancer Symptoms (Advanced)
If the cancer has metastasized, i.e. spread to other organs and around the body, symptoms may be caused by the metastases themselves and caused by them.
The most common symptoms of advanced prostate cancer are:
- Pains in the bones, back or other places;
- Loss of weight;
- Lack of strength and tiredness (due to anaemia, frequent in cancer patients).
Symptoms of spinal cord compression can also occur due to spinal metastases, generally very intense back pain, weakness and numbness in the lower limbs.
Intestinal changes, bladder control and pathological bone fractures are also possible.
Prostate Cancer Diagnosis
All men aged over 50 should screen for prostate cancer, according to the recommendations of the main urological associations (in Europe and the USA).
However, special attention is needed when there is a family history of cancer (father, brother, grandfather or uncle).
The diagnostic exams help identify the presence of a tumour before any symptoms occur, assess how far the cancer has evolved and characterise the tumour.
There are two essential diagnostic exams available:
- Digital rectal exam (DRE) (prostate palpation to detect the existence of nodules or abnormalities with a hard consistency);
- Prostate-Specific Antigen (PSA) test.
Complementary diagnostic methods may be necessary afterwards:
- Transrectal ultrasound (TRUS)
- Nuclear magnetic resonance (NMR)
- Computed tomography scan (CT scan)
Confirmation of the diagnosis always depends on the results of the prostate biopsy.
Dr. José Santos Dias explains how to proceed if diagnosed with prostate cancer.
Do you have any symptoms that would suggest prostate cancer?
Prostate Cancer Treatments
Prostate cancer treatment depends on the stage at which the disease is diagnosed.
Treatment should start as soon as possible after the diagnosis is confirmed. However, this can depend on the tumour’s stage of evolution, the severity of the situation and the possible need for more complementary exams to clarify certain features of the disease.
At this stage, it is important to talk to your doctor and clarify any doubts you may have. Discuss the different treatment options and their associated side effects.
It is normal for the treatment to involve multidisciplinary teams with different areas of specialisation, like urology, oncology and radiotherapy.
When diagnosed early, treatment is curative, i.e. the aim is to eliminate the cancer and cure the disease.
In more advanced cases, however, the treatment is palliative. The aim is to control the disease, prevent it from evolving and limit patients’ pains, improving quality of life.
Dr. José Santos Dias discusses the steps and exams used to define the characteristics and stages of prostate cancer.
Prostate Cancer Prognosis
The prognosis for this disease depends on the stage and evolution of the tumour (whether it is still local or has already spread). It also depends on the PSA level prior to treatment, histological degree (Gleason grading) and the consequent aggressivity of the tumour.
Localised tumours
After undergoing treatment for a localised tumour, the survival rates are:
- 98-100% after 5 years;
- 90-95% after 10 years.
The success rates for surgery, brachytherapy and external radiotherapy are similar.
Locally advanced tumours
The prognosis for locally advanced tumours is obviously worse. The survival rates are:
- Around 75% after 5 years;
- 60% after 10 years.
Advanced tumours
Hormone therapy patients have survival rates that vary according to age, tumour differentiation and the presence or absence of other simultaneous diseases.
Life expectancy falls abruptly if the tumour becomes resistant to castration (previously known as hormone resistant).
However, even in this case, significant progress has been achieved in the therapeutics for these patients with new drugs already being used in clinical practice. Drugs like abiraterone, enzalutamide, apalutamide and darolutamide show great results in treating these patients, who, several years ago, when reaching this stage, had much lower life expectancy and, furthermore, poor quality of life. This pattern has been completely changed today.
Dr. José Santos Dias
Clinical Director of the Instituto da Próstata
- Bacherlor's Degree from the Faculty of Medicine at the University of Lisbon
- Specialist in Urology
- Fellow of the European Board of Urology
- Autor dos livros "Tudo o que sempre quis saber Sobre Próstata", "Urologia fundamental na Prática Clínica", "Urologia em 10 minutos","Casos Clínicos de Urologia" e "Protocolos de Urgência em Urologia"
FAQs about Prostate Cancer
What are the chances of a man getting prostate cancer?
What is the prostate for?
What causes prostate cancer?
What are the symptoms or signs of prostate cancer?
How is prostate cancer diagnosed?
References
- DIAS, José Santos. Urologia Fundamental: na prática clínica. Lisboa: Lidel - Edições Técnicas, Lda, 2010.
- DIAS, José Santos. Tudo o que sempre quis saber sobre a Próstata. Lisboa: Lidel - Edições Técnicas, Lda, 2014.
- Tests to Diagnose and Stage Prostate Cancer - https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/how-diagnosed.html
- Prostate cancer - Symptoms and Causes - https://www.mayoclinic.org/diseases-conditions/prostate-cancer/symptoms-causes/syc-20353087
- Prostate cancer metastasis: Where does prostate cancer spread? - https://www.mayoclinic.org/diseases-conditions/prostate-cancer/expert-answers/prostate-cancer-metastasis/faq-20058270
- Deteção do Cancro da Próstata https://www.sns.gov.pt/noticias/2017/08/14/detecao-do-cancro-da-prostata/
- Prosate Cancer: Are There Symptoms? - https://www.webmd.com/prostate-cancer/video/marks-prostate-cancer-symptoms
- Survival Rates for Prostate Cancer - https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/survival-rates.html
- American Cancer Society. Cancer Facts & Figures 2020. Atlanta, Ga: American Cancer Society; 2020.
- Howlader N, Noone AM, Krapcho M, et al (eds). SEER Cancer Statistics Review, 1975-2016, National Cancer Institute, Bethesda, MD, https://seer.cancer.gov/csr/1975_2016/, based on November 2018 SEER data submission, posted to the SEER website, April 2019.