Essay: Prostate cancer – definition, risk factors, symptoms & diagnosis

Prostate cancer is the most common malignant tumor of the male (except for skin cancers) and the second more deaths because, second only to lung cancer. Despite the high mortality, most prostate cancers usually have slow-growing growing years restricted to the prostate without causing metastases.
In this paper we address the following points about prostate cancer (prostate adenocarcinoma):
What is and what it is for the prostate.
Risk factors for prostate cancer.
Symptoms of prostate cancer.
Diagnosis of prostate cancer.
Treatment of prostate cancer.
WHAT IS THE PROSTATE?
The prostate is a gland in the size of a walnut (3 cm diameter) with approximately 20 grams of weight, and this only in males. Located at the base of the bladder and surrounds the initial part of the urethra channel that carries urine from the bladder to the penis.
The prostate is part of the male reproductive system and is responsible for secretion of an alkaline fluid (with high pH) that protects the sperm from the vagina acidic environment and increases their mobility by facilitating the arrival thereof to the egg.
As has close relationship with the urethra, changes in prostate size may compress it and obstruct drainage of urine, leading to symptoms of prostatism, which will be explained later.
Anatomy próstataComo the prostate is leaning to the right, it can be palpated by digital rectal examination, one of the simplest methods of evaluation of the gland. An enlarged prostate size or irregular shape due to the presence of a tumor can be easily identified by this method. We’ll talk in more detail about the digital rectal examination on the diagnosis.
The prostate can grow and cause symptoms for three reasons:
– Benign prostatic hyperplasia (read: Benign Prostatic Hyperplasia – Symptoms and Treatment).
– Prostate cancer.
– Prostatitis (read: PROSTATITIS – Symptoms, Causes and Treatment).
For more details on the prostate, read: WHAT IS THE PROSTATE?
Benign prostatic hyperplasia and prostatitis have been addressed in a separate text. For now, we will stick to prostate cancer.
PROSTATE CANCER
As mentioned at the beginning of this text, prostate cancer is the most common male cancer. It is a tumor that is usually indolent, slowly growing and may remain asymptomatic for many years.
We do not know that prostate cancer arises and there are few identified risk factors; the main thing is age, with this rare cancer in patients younger than 40 years old and extremely common after 80 years. As humans begin to live more years, prostate disease start to get more and more frequent. As prostate cancer usually has slow growth, remaining asymptomatic for many years, many older people have the disease and do not know. In fact, it is estimated that between 50% and 80% of men over 80 years have prostate cancer at some stage of development.
In addition to age, are also risk factors have been identified:
– Afrodescendência (in this group, prostate cancer is more common and often more aggressive).
– Family history.
– Obesity (read: OBESITY AND METABOLIC SYNDROME | Definitions and consequences).
– Smoking (read: HARM CIGARETTE | Smoking cessation).
SYMPTOMS OF PROSTATE CANCER
Symptoms of prostate cancer typically occurs due to obstruction of the urethra by the tumor. However, as the disease tends to progress slowly, this obstruction usually only becomes apparent in very advanced stages of cancer.
Cancer próstataAo otherwise benign prostatic hyperplasia that causes the prostate to grow uniformly and symmetrically, prostate tumor growth is irregular and localized. Therefore, depending on the area where the cancer arises, there can be urethral compression and therefore symptoms of an enlarged prostate.
In the illustration to the side show two examples of prostate cancer: on the left, who grew next to the urethra causing its compression; right, another that it came away from the urethra and cause urinary symptoms only when very large.
When the tumor grows toward the urethra and cause obstruction, the most common symptoms are:
– Difficulty urinating
– Weak urine jet
– Pain during urination
– The need to urinate frequently, since, with obstruction of the passage of urine, the bladder is continuously filled, achieving only small empty volumes each time.
Here it is noteworthy that, for the reasons explained in the preceding paragraphs, these urinary symptoms are much more common in benign prostatic hyperplasia than in prostate cancer. Most elderly patients with urinary complaints have actually prostate hyperplasia. Since both diseases are very common in the elderly, the patient may even have hyperplasia and cancer together, but the symptoms are usually caused by the first.
Currently most prostate cancers are detected at early stages, before they cause symptoms by examining PSA, the prostate ultrasound and digital rectal examination.
The hematuria and hematospermia (blood in the urine and sperm, respectively) can occur in prostate cancer, but are not common symptoms. In such cases one should also think of kidney stones, urinary tract infection or bladder cancer. (Read: hematuria (bloody urine).
Erectile dysfunction can be a symptom of prostate cancer, but it is also unusual. The vast majority of cases of erectile difficulty in the elderly is not caused by prostate cancer (read: SEXUAL IMPOTENCE | Causes and Treatment).
Some patients who do not undergo tests for disease screening can only discover the tumor when prostate metastases begin to cause symptoms. If the tumor arise away from the urethra, it will cause metastases before cause urinary symptoms. In this case, most common symptoms are pain and fractures metastases to the bone.
To avoid situations like this latter, the international societies of urology recommend screening for prostate carcinoma of all men over 45 years old.
To learn more about the symptoms of prostate disease, read: SYMPTOMS OF PROSTATE.
PROSTATE CANCER DIAGNOSIS
There is a points table called SCORE International Prostate Symptom. Seven questions and each receives a score from 0 to 5
How many times was the feeling of not completely emptying the bladder?
How many times had to urinate again less than two hours after urinating?
How many times noted that, when urinating, stopped and started again several times?
How many times noted that it was difficult to contain urine?
How many times noted that the urine stream was weak?
How many times had to force to begin urination?
How often, on average, we had to get up at night to urinate?
0 = None
1 = Less than 1 time in 5
2 = Less than half of the times
3 = About half the time
4 = More than half the time
5 = Almost always
Light: 0 to 7;
Moderate: 8-19;
Severe: 20 or more
The score above assesses the severity of prostatic symptoms, but does not differentiate between BPH, prostatitis and cancer. The differential diagnosis involves the digital rectal exam, PSA dosage, transrectal ultrasound and prostate biopsy.
DRE – próstataO of rectal cancer can detect those tumors that grow toward the rectum. However, up to 35% of prostate cancers at an early stage are not detected by touch. The illustration above shows an example of tumor not detectable by digital rectal examination.
PSA is a prostate disease marker, collected by blood tests, which rises in the HPB and especially in prostate cancer.
PSA less than 2.5 = Low risk of cancer.
PSA between 2.5 and 10 = Intermediate risk of cancer.
PSA greater than 10 = high risk of cancer.
PSA greater than 20 = very high risk of cancer and high chance of disease with metastases.
When PSA and digital rectal cancer raise suspicions, prostate biopsy should be performed (read: BIOPSY PROSTATE | Indications and complications).
Once carried out the diagnosis of cancer, it should assess the degree of invasion (tumor stage) and aggressiveness (Gleason score).
The Gleason score is obtained after analysis of prostate biopsy, ranging from 1 to 10; the higher the value, the more aggressive are the cancer cells.
Patients with local tumor invasion signals, Gleason higher than 6 or very high PSA at high risk of disseminated disease and should perform bone scan to identify possible bone metastases.
After this initial evaluation of prostate cancer is divided into four groups:
– Group I: early disease with microscopic and confined to the prostate tumor (PSA less than 10 and Gleason less than 6)
– Group II: Tumor confined to the prostate, but big enough to be palpated by digital rectal examination (PSA less than 20 or Gleason = 7)
– Group III: Tumor already invasion of organs around the prostate
– Group IV: Distant metastases
PROSTATE CANCER TREATMENT
Prostate cancers in early stages are potentially curable by surgery and radiotherapy. Low aggressive cancers take between ten to twenty years to invade other tissues. When occur in patients with advanced age can not be treated, because the risks and consequences of treatment not justified by someone with lower life expectancy than is required for tumor progression.
Complications of treatment include impotence, urinary incontinence and decreased libido.
advanced tumors without metastasis is treated with radiotherapy.
Tumors with metastases are treated with drugs that make hormonal blockade (inhibition of testosterone) and usually have a poor prognosis.