What is the Prostate?
The prostate is a walnut-sized organ that produces fluid and nutrients
for sperm during ejaculation. The gland is located just under the
bladder and in front of the rectum, the lower part of the bowel. The
urethra, the narrow tube that spans the length of the penis and that
carries both urine and semen out of the body, runs through the prostate.
The glandular cells of the prostate normally function to produce a
fluid that is released into the urethra during ejaculation. This fluid
forms part of the seminal fluid, which nourishes the sperm. Secretions
from the prostate increase the pH of the semen and help to neutralize
the acidity of the female vagina.
The prostate is surrounded by blood and lymphatic vessels:
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Blood vessels are part of the circulatory system. They supply oxygen
and nutrients and remove waste from the cells of the prostate.
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Lymphatic vessels are part of a large network termed the lymphatic
system. These vessels collect and carry fluid and cells from the tissues
of the body. Smaller lymphatic vessels merge with larger ones, as
streams merge into a river. Large vessels empty into grape-like clusters
of lymphatic tissue called lymph nodes. The lymphatic vessels of the
prostate carry lymphatic fluid to a mass of lymph nodes located in the
pelvic region.Prostate
cancer is the uncontrolled growth of cells in the prostate gland, a
gland found only in men. Although the prostate is made up of several
cell types, almost all prostate cancers develop in the glandular cells.
Cancer of gland cells is known as adenocarcinoma.
Prostate cancer symptoms usually start in the area of the gland that can be felt by a doctor during a DRE, thus leading to early prostate cancer diagnosis.
Most men will not experience any symptoms of prostate cancer if it is caught early. However, some men do, and these symptoms may include the following.
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A need to urinate frequently, especially at night
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Difficulty starting urination or holding back urine
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Weak or interrupted flow of urine
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Painful or burning urination
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Difficulty in having an erection
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Painful ejaculation
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Blood in urine or semen
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Frequent pain or stiffness in the lower back, hips, or upper thighs
Although most patients will have urinary symptoms related primarily to
BPH, a workup for prostate cancer may be indicated by a DRE or an abnormal Prostate Specific Antigen (PSA) blood test.
Diagnosis of prostate cancer
A Pelvic ultrasound scan in males is used to view the bladder and prostate (An ultrasound examination, also commonly referred to as a sonogram).
Amongst other conditions, ultrasound can detect enlargement of the prostate (benign prostatic hypertrophy) and tumours.
The bladder is an organ made of smooth muscle that stores urine until
ready for release. The most common reason for bladder ultrasound is to
assess bladder emptying by measuring residual urine after urination.
Many conditions may result in disorders of bladder emptying and these
include an enlarged prostate,
urethral stricture or bladder dysfunction. Bladder ultrasound may also provide information about the bladder wall, the presence of
diverticula of the bladder, the size of the prostate, the presence of stones or large tumors in the bladder.
Another common indication for ultrasound is obtaining the volume or size of the prostate for treatment planning purposes.
Digital rectal exam Digital rectal exams (DRE) are very useful for the detection of
abnormalities, including cancer, in the rectum. A doctor inserts a
gloved, lubricated finger in the rectum and feels for abnormalities. In
men, digital rectal exams are also used to detect changes in prostate
that could indicate an abnormal condition, including cancer. The
procedure is very quick and although it may be uncomfortable, it is not
painful.
An enlarged prostate means the gland has grown bigger. Prostate
enlargement happens to almost all men as they get older. As the gland
grows, it can press on the urethra and cause urination and bladder
problems. An enlarged prostate is often called benign prostatic hyperplasia (BPH) or benign prostatic hypertrophy.
BPH involves hyperplasia
(an increase in the number of cells) rather than hypertrophy (a growth
in the size of individual cells), but the two terms are often used
interchangeably, even amongst urologists
PSA test The prostate specific antigen is a glycoprotein produced by prostate cells and is a normal component of semen.
When abnormal events occur in the prostate, such as prostate cancer,
the overabundance of prostate cells, the overproduction of PSA, or the
leaking of PSA into the bloodstream may result in a measurable increase
in the level of PSA in the blood. Blood test are used to assess the
level of PSA in the blood. A higher-than-normal level of PSA might
indicate a problem with the prostate, including, but not limited to,
cancer.
Normal PSA values In general, a PSA level less than 4 ng/ml is considered normal, and
greater than 10 ng/ml is considered high. Levels between 4 and 10 ng/ml
represent a grey area in which a doctor may consider a digital rectal
exam before recommending further testing.
Interpretation of PSA test results The interpretation of PSA levels is not straightforward. Elevated PSA
levels indicate something has caused more PSA than usual to enter the
bloodstream from the prostate, but the test is not able to identify the
cause of the elevation. Several factors can cause a rise in PSA levels,
such as a prostate infection or benign enlargement of the prostate.(1) Many men with elevated PSA levels DO NOT
have prostate cancer. Additionally, not all prostate cancers cause PSA
levels to rise. These cancers would not be detected by the PSA test.
Prostate cancer, unlike many other cancers, often grows slowly, and does
not always pose a significant health risk. Some prostate cancers do
grow quickly, but neither the PSA test nor any available test today can
differentiate between slow and fast growing prostate cancers. While some
people will benefit from having the PSA test, patients should discuss
the benefits and limitations of this test with their health care
provider before having it performed and when interpreting the results. (http://sciencedoing.blogspot.in/2013/08/prostate-specific-antigen-misnomer-and.html)
Normal ranges by age group commonly used include
- Men below age 50: PSA less than 2.5
- Men 50 - 59 years: PSA level less than 3.5
- Men 60 - 69 years: PSA level less than 4.5
- Men older than 70 years: PSA level less than 6.5
Increased levels of PSA may suggest the presence of prostate cancer.
However, prostate cancer can also be present in the complete absence of
an elevated PSA level, in which case the test result would be a false negative.PSA levels can be also increased by prostatitis, irritation, benign prostatic hyperplasia (BPH), and recent ejaculation, producing a false positive result. Digital rectal examination (DRE) has been shown in several studies
to produce an increase in PSA. However, the effect is clinically
insignificant, since DRE causes the most substantial increases in
patients with PSA levels already elevated over 4.0 ng/mL.
Free PSA Most PSA in the blood is bound to serum proteins. A small amount is not
protein bound and is called 'free PSA'. In men with prostate cancer the
ratio of free (unbound) PSA to total PSA is decreased. The risk of
cancer increases if the free to total ratio is less than 25%. (See graph
at right.) The lower the ratio is, the greater the probability of
prostate cancer. Measuring the ratio of free to total PSA appears to be
particularly promising for eliminating unnecessary biopsies in men with PSA levels between 4 and 10 ng/mL. However, both total and free PSA increase immediately after ejaculation, returning slowly to baseline levels within 24 hours.
Biopsy Non invasive diagnostic techniques, like MRI, Ultrasound, CT or PET, are very useful but in some cases when a suspicious abnormality (lesion) is discovered a doctor may perform a biopsy
to determine its exact characteristics. A biopsy is the removal of
either a portion of a lesion (incisional) or the entire lesion
(excisional). The tissues is then sent to a lab where a pathologist
will diagnose the sample. There are two categories of biopsies.
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Fine Needle Aspiration (FNA):
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Benign - the mass is not of much concern and will not cause any significant problems as long as it remains unchanged.
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Atypically indeterminate - a diagnosis cannot be obtained from the sample. Other tests are needed to determine the nature of the lesion.
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Suspicious/probably malignant
- not a diagnosis of cancer. This type of diagnosis requires additional
investigation because the sample has abnormal characteristics. This
lesion should be biopsied with a more complete method to determine
whether a malignancy (cancer) is present.
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Malignant - a diagnosis of cancer; should be biopsied and tested for exact tumor makeup to prepare for treatment.
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Unsatisfactory - a diagnosis cannot be determined from the sample
because of insufficient sample size, processing or other machine or
human errors.
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Core Needle Biopsy (CNB): Because cancer cells are dividing in an abnormal fashion, they make the
tissue around them appear disorganized. By examining collections of
cells (tissue) instead of individual cells, pathologists get a good
sense for the health of the organ from which the sample was removed. The
study of tissues is called histology and the study of abnormal tissues
is called histopathology.
Cytological examination (prostate secretion) The study of cells, their origin, structure, function, and pathology is
called cytology.
Cells are continually shed (exfoliated) from tissues
that line the cavities and hollow organs of the body. These exfoliated
cells may float in the fluid and mucous material bathes or passes
through these cavities. These cells can be examined microscopically to
determine their tissue of origin and whether or not they are malignant.
(As a further guide, histology is the study of tissues, while cytology is the study of cells.)
Histopathological examination Diagnosis of prostatic carcinoma requires a synthesis of a constellation
of histological attributes that allows for a definitive diagnosis. A
conceptual framework for a rationale approach to this diagnosis entails
application of major and minor criteria:
Major criteria
- Architectural:
infiltrative small glands or cribriform glands too large or irregular
to represent high‐grade prostatic intraepithelial neoplasia (PIN)
- Single cell layer (absence of basal cells)
- Nuclear atypia: nuclear and nucleolar enlargement
Minor criteria
- Intraluminal wispy blue mucin (blue‐tinged mucinous secretions)
- Pink amorphous secretions
- Mitotic figures
- Intraluminal crystalloids
- Adjacent high‐grade PIN
- Amphophilic cytoplasm
- Nuclear hyperchromasia
Gleason score The pathologist assigns a Gleason score based on the sum of two numbers: the first number is the grade of the most common tumor
pattern, the second number is the grade of the second most common
pattern.
A pathologist examines the biopsy specimen and attempts to give a score to the two patterns.
- First called the primary grade, represents the majority of tumor (has to be greater than 50% of the total pattern seen).
- Second - a secondary grade - relates to the minority of the tumor
(has to be less than 50%, but at least 5%, of the pattern of the total
cancer observed).
If there are three patterns the first number is the most common
and the second is the one with the highest grade. For example, if the
most common tumor pattern was grade 3, but some cells were found to be
grade 4, the Gleason Score would be 3+4 = 7. The Gleason Grade or Gleason Pattern ranges from 1 to 5, with 5 having
the worst prognosis. The Gleason Score ranges from 2 to 10, with 10
having the worst prognosis. For Gleason Score 7, a Gleason 4+3 is a more
aggressive cancer than a Gleason 3+4.
The scoring system is named after Donald Gleason, a pathologist at the Minneapolis Veterans Affairs Hospital who developed it; 'modified Gleason score' has higher performance than the original one,
and is currently assumed standard in urological pathology.
Gleason patterns are associated with the following features:
- Pattern 1 - The cancerous prostate closely resembles normal prostate
tissue. The glands are small, well-formed, and closely packed.
- Pattern 2 - The tissue still has well-formed glands, but they are larger and have more tissue between them.
- Pattern 3 - The tissue still has recognizable glands, but the cells are darker. At high magnification, some of these cells have left the glands and are beginning to invade the surrounding tissue.
- Pattern 4 - The tissue has few recognizable glands. Many cells are invading the surrounding tissue
- Pattern 5 - The tissue does not have recognizable glands. There are
often just sheets of cells throughout the surrounding tissue.
In present form of the Gleason system, prostate cancer of Gleason
pattern 1 and 2 are almost never seen, and by definition are almost
never seen on biopsy. Gleason pattern 3 is by far the most common. Thus a
Gleason score 3+3=6 cancer is to be regarded as LOWEST grade seen in
practice, and indeed these cancers usually have rather good prognoses.
Staging and grading of prostate cancer: After examination and biopsy, doctors will "stage" and "grade" prostate cancer with a system of letters and numbers.
Grade: Grade refers to the expected aggressiveness of
the tumor based on the biopsy. The most common grading system is the
Gleason system. Grades 1 and 2 are closer in appearance to normal
glands, and are the slowest growing, better behaving tumors. Grades 4
and 5 have more variations in size of tumor cells and loss of glandular
appearance, and are the more aggressive tumors.
Stage: The clinical stage of a cancer is the extent of
disease, whether it is localized, spread regionally, or spread more
widely to lymph nodes or bones.
A system of staging used by the National Cancer Institute and most doctors is called TNM Staging (clinical and pathological).
This stands for:
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Tumor size - how big the tumor is and has it spread in the area
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Lymph Nodes - are any lymph nodes positive for cancer and how many
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Metastasis - has the cancer spread to any other parts of the body
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some related blog post
Prostate Cancer Risk Factors
The risk of developing prostate cancer can be linked to age, race/ethnicity, and family history of the disease.
How to Reduce the Risk of Prostate Cancer
Lycopene and antioxidants found in tomatoes and other pink and red
foods may reduce prostate cancer risks. Men should consume a diet that
includes a variety of fruits and vegetables. Because these foods tend to
be lower in calories, choosing these foods instead of those higher in
calories may also to less obesity.
Antioxidant and lycopene rich food supplement is beneficial, as from latest research findings
# 2013-08-24, WASHINGTON, Aug. 23 (Xinhua) -- U.S. researchers said Friday that a
greater consumption of fruits and vegetables may reduce the risk of
developing invasive bladder cancer in women.
Researchers from the University of Hawaii wrote in the Journal of
Nutrition that they analyzed data collected from 185,885 older adults
over a period of 12.5 years. Overall, 152 women and 429 men were
diagnosed with invasive bladder cancer.
After adjusting for variables related to cancer risk, such as age,
the researchers found that women who consumed the most fruits and
vegetables had the lowest bladder risk.
The researchers said women consuming the most yellow-orange
vegetables were 52 percent less likely to have bladder cancer than women
consuming the least yellow-orange vegetables.
The study also suggested that women with the highest intake of vitamins A, C and E had the lowest risk of bladder cancer.
There were, however, no associations between fruit and vegetable intake and invasive bladder cancer in men, it said.
"Our study supports the fruit and vegetable recommendation for cancer
prevention," researcher Song-Yi Park at the University of Hawaii Cancer
Center said in a statement.
"However, further investigation is needed to understand and explain
why the reduced cancer risk with higher consumption of fruits and
vegetables was confined to only women," Park added.
* Genetics:
Recently, a mutation in a gene called HOXB13
has been linked to early onset prostate cancer that runs in families.
This mutation is rare, though, found in less than 2% of the men with
prostate cancer that were studied.
The HOXB13 gene and most of the genes
that have been studied so far are from chromosomes that are inherited
from both parents. Some research has found that a certain variant of
mitochondrial DNA, which is inherited only from a person's mother, might
double or even triple a man's risk of developing prostate cancer.
One of the biggest problems now facing men
with prostate cancer and their doctors is figuring out which cancers are
likely to stay within the gland and which are more likely to grow and
spread (and definitely need treatment). New discoveries may help with this in the near future. For example, the product of a gene known as EZH2
seems to appear more often in advanced prostate cancers than in those
at an early stage. Researchers are now trying to decide whether the
presence of this gene product, or others, indicates that a cancer is
more aggressive. This could eventually help tell which men need
treatment and which might be better served by active surveillance.
* a new diagnostic tool :
# checking for the presence of the protein Engrailed-2 (EN2) in the urine. Homeobox protein engrailed-2 is a protein that in humans is encoded by the EN2 gene. A method for diagnosing prostate cancer
by detection of EN2 in urine has developed. The results of a clinical
trial of 288 men suggest that EN2 could be a marker for prostate cancer
which might prove more reliable than current methods that use prostate-specific antigen
(PSA). If effective, a urine test is considered easier and less
embarrassing for the patient than blood tests or rectal examinations
# thankfully consulted and referred from:
http://www.webmd.com/urinary-incontinence-oab/picture-of-the-prostate
http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-new-research
http://www.cancerquest.org
https://winshipcancer.emory.edu
http://training.seer.cancer.gov
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860598/
http://www.cancer.gov/dictionary?cdrid=45696
http://en.wikipedia.org
http://en.wikipedia.org/wiki/EN2_%28gene%29
http://news.xinhuanet.com/english/health/2013-08/24/c_132658367.htm
