Prostate Cancer

Prostate cancer is malignant and uncontrolled growth of cells in the prostate, a small gland located between the bladder and the penis.

Compared to other types of cancer, prostate cancer is usually slow growing and dependent on testosterone to grow. This cancer usually involves the epithelial cells of the inner lining of the prostate gland, and is therefore classified as an adenocarcinoma.

Tumor cells in prostate cancer.
Prostate cancer cells.

Prostate Cancer Symptoms

In early stages, there are no noticeable symptoms of prostate cancer. It is estimated that between 60 to 70% of men of 80 years of age or older living with prostate cancer do not show symptoms.

In later stages, prostate cancer symptoms include:

Inability to urinate
Difficulty in starting to urinate (hesitancy in urinating)
Weak urine stream or dribbling
Frequent urination
Waking up in the middle of the night to urinate or due to urges to urinate (also called nocturia)
Pain or burning sensation while urinating (called dysuria)
Blood in the urine (hematuria)
Feeling that the bladder is not empty even after multiple attempts of urination
Pain in the lower back, hip or pelvis, abdomen, and upper thighs.

These symptoms are similar to other diseases, such as benign prostatic hyperplasia, prostatitis, and urinary tract infection.

In advanced cases of prostate cancer, where the cancer has metastasized or spread to other organs of the body, the following symptoms may be present:

Loss of appetite and weight loss
Swelling or edema of the legs and feet
Pain in the bone, especially in the abdomen, pelvis, and lower back.

Prostate Cancer Diagnosis

Your doctor would use the following tests to diagnose prostate problems:

Digital rectal exam
In this exam, enlarged prostate can be felt by inserting a lubricated finger into the rectum.

Urinalysis or laboratory analysis of the urine
Prostate-specific antigen (PSA) test
In this test, elevated level of prostate-specific antigen (PSA) in the blood may indicate an enlargement, infection, and also prostate cancer.

PSA test is often used as a screening test for prostate cancer, however, positive result does not equal proof of cancer because other prostate conditions also can cause high PSA levels.
Prostate Biopsy
To confirm the presence of prostate cancer, a sample of the prostate tissue is taken.

In this procedure, a needle is inserted through the rectum (called a transrectal biopsy), through the urethra, or through the perineum (the area between the anus and the scrotum). The most common technique is transrectal, often with the guide of an ultrasound.

Histopathology of adenocarcinoma of the prostate.

Prostate cancer (adenocarcinoma)

Risk Factors for Developing Prostate Cancer

Although the exact cause of prostate cancer is unknown, certain risk factors are known to increase the likelihood of developing this condition:

Age
Age is the most important risk-factor in prostate cancer. Both incidence and mortality rate increases significantly with age: more than 75% of new diagnosis and 90% of death occur in men older than 65.
Race / Ethnicity
African Americans are at greater risk of developing and dying from prostate cancer when compared to Caucasian population in the United States. On the other hand, Asian men in Japan and China have much lower incidence of prostate cancer diagnosis.
Genetics
Family history plays a key role in determining your chances of developing prostate cancer. Both having relatives diagnosed before the age of 55 and the number of family member with the disease increases your risk, for example:

Relative with cancer	Increase in risk
1 (brother / father)	2x
2	5x
3+	Almost certainty

Diet
Prostate cancer is more commonly found in countries with high-fat diet. Indeed, diet maybe the determining factor why Asian men in China and Japan are at much lower risk of developing this condition.
Obesity
Being overweight or having a body mass index or over 32.5 is a risk factor as well. Weight gain at an earlier age and keeping that weight on may bring a greater risk of developing the more aggressive form of prostate cancer.
Testosterone
While the link between testosterone and prostate cancer is not well established, it is thought that the growth of the cancer cells are nourished by testosterone - and thus controlling the level of this hormone may help prevent or slow down prostate cancer.

Nevertheless, studies have shown that high testosterone level, vasectomy, and frequent sexual activities do not cause prostate cancer.
Exposure to toxins and carcinogens
Exposure to high levels of cadmium, pesticides such as methyl bromide, herbicides and cigarette smoke can increase the risk. Veterans exposed to Agent Orange, a herbicide used to defoliate trees in jungle warfare, may be twice as likely to develop prostate cancer.

Prostate Cancer Treatment

Treatment for prostate cancer include:

Radiation Therapy
In this treatment, high-energy rays or radiactive particles are used to kill rapidly growing cells, such as cancer cells. The two forms of radiation therapy are external beam therapy, where high-energy rays are aimed at the prostate, and interstitial radiation or brachytherapy, where radiactive materials or seeds are implanted directly into or near the cancer.
Surgery
Surgical treatment of prostate cancer usually means removal of the prostate gland or prostatectomy. This can be done either through an incision in the lower abdomen (retropubic approach) or between the rectum and the scrotum (perineal approach).

laparoscopic surgery

Watchful Waiting

In many instances, however, your doctor may not recommend any treatment. Instead, the patient is advised to monitor the situation closely by having frequent medical checkups, PSA testing, and biopsies in combination with dietary changes.

This watchful waiting (also called active surveillance, expectant therapy or simply just observation) is often used since prostate cancer grows so slowly that a man is likely to die naturally or of other causes than the cancer itself. If the cancer becomes a health threat, then the treatment options above may be used.

Reference:
Yahoo! Health - Prostate Cancer
National Prostate Cancer Coalition
MedlinePlus - Prostate Cancer