Signs and symptoms of prostate cancer

During the early stages of prostate cancer, there are usually no distinct symptoms. At the early stages, most men normally discover they have prostate cancer after a routine check-up or blood test. 

Some noticeable symptoms include one or more of the following:

•         The patient urinates more often, especially at night
•         Patient may find it hard to start urinating or keep urinating once he or she has started
•         In the urine, blood may be observed
•         During urination and ejaculation (less common), pain may be expected
•         Achieving or maintaining an erection may not be easy (less common).

   The following symptoms could also occurred at the later stages of prostate cancer: 

• Bone pain, often occurred in the pelvis, ribs, or spine (vertebrae),
• Pain could be felt at the proximal part of the femur 
• If cancer has spread to the spine and compressed the spinal cord, it will cause leg weakness, urinary incontinence, as well as fecal(faeces) incontinence. (Incontinence means a lack of control) 

  For more information visit: http://www.medicalnewstoday.com/articles/150086.php?page=2#causes_of_prostate_cancer

Diagnosis for Prostate Cancer

Tests for Prostate Cancer
Normally, patients are diagnosed with prostate cancer when they are screened with a prostate-specific antigen (PSA) blood test or a digital rectal exam (DRE). At early stages, patients may not realized they have prostate cancer as the symptoms are not obvious while at advanced stages, patients may suspect they have prostate cancer due to more apparent symptoms. In order to confirm the diagnosis, tests are required. Prostate biopsy is the only accurate, actual diagnosis of prostate cancer. These are some of the general tests for prostate cancer and I will explain some in detail, for example:

Medical history and physical examination
PSA blood test
Transrectal ultrasound (TRUS)
Prostate biopsy- Grade (Gleason score) of prostate cancer
Imaging tests to look for prostate cancer spread
Lymph node biopsy

Medical history and physical examination
Doctors will ask if you have any urinary or sexual problems, and how long you have had them as they are the common symptoms of prostate cancer. They may also asked for your family history as it is considered a possible risk factor. Doctors will examine through the DRE. If the patient is tested positive, the DRE can sometimes help identify if it’s only on one side of the prostate, if it’s on both sides, it’s likely to have spread beyond the prostate to nearby tissues. Doctors may examined other parts of the body and order additional tests.

PSA blood test
Although PSA is used mainly to screen for prostate cancer in men without symptoms, it’s one of the first tests done in men who have symptoms that might be caused by prostate cancer. Generally, men without prostate cancer have PSA levels under 4 nanograms per milliliter (ng/mL) of blood. The chance of having prostate cancer increases as the PSA level increases.

Prostate biopsy- Grade (Gleason score) of prostate cancer
Prostate cancers are graded according to the Gleason system. This system assigns a Gleason grade based on how similar the cancer prostate tissue is compared to the normal prostate tissue.
If the cancer prostate tissue is very similar to normal prostate tissue, a grade of 1 is assigned.
If the cancer prostate tissue is very different, it is given a grade of 5.
Grades 2-4 have features in between these extremes.
Generally, prostate cancer is grade 3 or higher, and grades 1 and 2 are not regarded.

Imaging tests to look for prostate cancer spread
Imaging tests use x-rays, magnetic fields, sound waves, or radioactive substances to create pictures of the inside of patient's body.
Bone Scan:
If prostate cancer spreads to distant sites, it often goes to the bones first. A bone scan can help show whether cancer has reached the bones.
For bone scan, patients are injected with a small amount of low-level radioactive material, which settles in damaged areas of bone throughout the body. A special camera detects the radioactivity and creates a picture of patients' skeletons.
A bone scan may suggest cancer in the bone, but to make an more accurate diagnosis, other tests such as plain x-rays, CT or MRI scans, or even a bone biopsy are recommended.
Computed tomography (CT) scan:
A CT scan uses x-rays to make detailed, cross-sectional images of your body. It can sometimes help tell if prostate cancer has spread into nearby lymph nodes. If your prostate cancer has relapsed after treatment, the CT scan can often tell if it is growing into other organs or structures in your pelvis.
However, MRI is a better choice for looking at the prostate gland itself.
Magnetic resonance imaging (MRI):
Similar to CT scans, MRI scans show detailed images of soft tissues in the body. However, MRI scans use radio waves and strong magnets instead of x-rays. Hence, the patient is very safe as he or she is not exposed to radiation. A contrast material called gadolinium may be injected into a vein before the scan to better see details.
MRI scans can give a very clear picture of the prostate and show if the cancer has spread outside the prostate into the seminal vesicles or other nearby structures. This can be paramount in determining the treatment options. 
To improve the accuracy of the MRI, you might have a probe, called an endorectal coil, placed inside your rectum for the scan. This can be uncomfortable. If needed, medicine can be given before the scan to make the patient feel sleepy (sedation).

Lymph node biopsy
In a lymph node biopsy, one or more lymph nodes are removed to look for the presence of cancer cells. It can be used to find out if the cancer has spread from the prostate to nearby lymph nodes.

For more information, check out this website:
 http://www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-diagnosis

Pathophysiology of prostate cancer

Prostate cancer forms when the rate of cell death and cell division are not equal, which leads to uncontrolled tumor growth. After the beginning of the transformational event, further mutation of a large number of genes, such as genes for p53 and retinoblastoma, that lead to tumor progression and proliferation of cancer. Around 95% of the prostate cancer are adenocarcinomas.

About 4% of the cases of prostate cancer have transitional cell morphology and believed to arise from the urothelial lining of the prostatic urethra. The few cases that have neuroendocrine morphology are believed to arise from the neuroendocrine stem cells normally present in the prostate or from aberrant differentiation programs during cell transformation.

Squamous cell carcinomas constitute less than 1% of all prostate carcinomas. In many cases, prostate carcinomas with squamous differentiation arise after radiation or hormone treatment.

Of prostate cancer cases, 70% arise in the peripheral zone, 15-20% arise in the central zone, and 10-15% arise in the transitional zone. Most prostate cancers are multifocal, with the synchronous involvement of multiple zones of the prostate, which may be due to clonal and nonclonal tumors.

When these cancers are locally invasive, the transitional-zone tumors spread to the bladder neck, while the peripheral-zone tumors extend into the ejaculatory ducts and seminal vesicles. Penetration through the prostatic capsule and along the perineural or vascular spaces occurs relatively late.

The mechanism for distant metastasis is poorly understood. Cancer spreads to bone early, often without significant lymphadenopathy. Currently, 2 predominant theories have been proposed for spread: the mechanical theory and the seed-and-soil theory.

The mechanical theory attributes metastasis to direct spread through the lymphatics and venous spaces into the lower lumbar spine. Advocates of the seed-and-soil theory, however, believe that tissue factors that allow for preferential growth in certain tissues, such as bone, must be present. Lung, liver, and adrenal metastases have also been documented. Specific tissue growth factors and extracellular matrices are possible examples.

The doubling time in early stage disease is variable. In the majority of cases, doubling time is longer than 4 years. Only a small percentage of prostate cancers double in less than 2 years. Doubling time tends to accelerate as the tumor grows and becomes more aggressive. Larger tumors usually have a higher Gleason grade and a faster doubling time.

The standard approach for grading prostate cancer depends on a Gleason score, which is based on pathologic evaluation of a prostatectomy specimen and is commonly estimated from prostate biopsy tissue. Prostate cancer patterns are assigned a number from 1-5; the score is created by adding the most common pattern and the highest-grade patterns.

This picture shows about how prostate cancer looks like under the microscope. Immunohistochemical stains showing normal basal cells(brown) in a benign gland with no basal cells in malignant glands (on the right side with no brown staining). Malignant glands show increased expression of racemase (red cytoplasmic stain).

For information check out: http://emedicine.medscape.com/article/1967731-overview#showall

Study of prostate cancer

Prostate cancer - a disease which only affects men.

The prostate is in front of the rectum, and directly under the bladder. It is about the size of a walnut. There are thousands of tiny glands in the prostate - they produce a fluid that forms part of the semen. This fluid protects and nourishes the sperm. With the use of prostate muscle fibers, prostate is also involve in urine control. When the urethra pass through the prostate, these muscle fibers in the prostate contract and release, controlling the flow of urine flowing through the urethra.

In most of the cases, the prostate cancer starts in the gland cells. Most of the time prostate cancer is a slow progressing disease. Actually, many men die of old do not even know that they had prostate cancer. The patient only knows it when they carried out an autopsy with a doctor. Many cases shows that around 80% of the men died without knowing they have prostate cancer, even the doctors.

The main causes of prostate cancer are due to the following factors:

1.Age: age is considered as a primary factor, older man will have a higher risk of getting prostate cancer, it is rare among men under the age of 45, but much more common after the age of 50.

2.Diet: studies have shown that lack in vitamin D, and diet of  high in red meat may raise a person's chances of developing prostate cancer.

3.Sexual transmitted disease: men who had gonorrhea will have a higher chance of developing prostate cancer, according to research by the University of Michigan Health System.

4.Genetic factors: Genetic background may contribute to prostate cancer risk, as suggested by associations with race, family, and specific gene variants. Men who have a first-degree relative (father or brother) with prostate cancer have twice the risk of developing prostate cancer, and those with two first-degree relatives affected have a fivefold greater risk compared with men with no family history.

Prostate cancer(http://www.medicalnewstoday.com/articles/150086.php?page=2#causes_of_prostate_cancer)

Welcome to our blog!!!!

Hi everyone!!

We are Year 1 students from Biomedical Science(BMS) in Ngee Ann Polytechnic(NP). This blog is a project for our module- Introduction to Medical Science, and the purpose of this blog is to share important knowledge about prostate cancer with you! Over the course of this 2 months, we will definitely post something about the mechanism of prostate cancer. However, we cannot decide to tell you more about the diagnosis or treatment of prostate cancer, so why not you comment below and we will decide based on your comments. We hope you will find our blog posts educational and interesting at the same time.

Thank you and enjoy our blog!