Prostate cancer is one of the most common cancers among men. Prostate cancer, also known as carcinoma of the prostate, is the development of cancer in the prostate, a gland in the male reproductive system. The prostate is below the bladder and in front of the rectum. The size of the prostate changes with age. Prostate cancer affects mainly older men. About 80% of cases are in men over 65, and less than 1% of cases are in men under 50. This type of cancer grows relatively slowly often causing no symptoms until it is in an advanced stage. The cancer cells may spread from the prostate to other parts of the body, particularly the bones and lymph nodes. Almost all prostate cancers are adenocarcinomas, which is particularly formed from glandular structures in epithelial tissues. The specific causes of prostate cancer are not known for certainty however, there are many possible factors that could be the cause such as age, lifestyle, race, medications and genetics, to name a few.

 

Treatment of prostate cancer is based on the stage of the cancer. Among some of the treatments, if the cancer is in its early stage, are observing and waiting, radical prostatectomy, brachytherapy, intense modulated radiotherapy, hormonal therapy etc. If the cancer is detected at a more advanced stage, there are therapy combinations that can be performed along with surgically removing the prostate. The known treatments however, can result in complications such as metastasis of the cancer, which means the cancer can spread to other parts of the body through bloodstream or the lymphatic system. It can also cause urinary incontinence as well as erectile dysfunctions, loss of fertility, and bowel dysfunction.

A new treatment described as “truly transformative” can treat early stage prostate cancer without causing severe side effects. This treatment uses lasers and a drug made from deep-sea bacteria to eliminate the cancer in a non-invasive way. The technique could save many patients from the trauma of surgery and many complicated side effects. The new treatment uses a light-sensitive chemical made by bacteria that destroys tumors by releasing ‘free radical’ molecules after activation by laser light. Optic laser fibers are inserted through the perineum in the prostate to cover the desired treatment area and then the drug is administered intravenously over 10 minutes. The drug is then activated in the treatment zone for 20 minutes by laser light to kill the cancerous cells.

 

Illustration of light sensing drug being activated through multiple optical fibers positioned inside the prostate gland: (a) and (b) show two different instances during the same treatment session.

Experts at University College London conducted this study and the results were published in The Lancet Oncology journal. Scientists at the Weizmann Institute of Science in Israel developed the technique several years ago after the discovery of light-sensitive bacteria. The study involved over 400 prostate cancer patients and 50% of the patients with early stage prostate cancer who received this treatment had no signs of the disease two years after the treatment as compared to the other standard treatments when only 13.5% of treated patients show no signs of cancer. What is truly transformative about this new treatment called 'vascular-targeted photodynamic therapy’ is that side effects are very minimal compare to standard treatments that can result in lifelong impotence and incontinence. The drug used called photosensitizer destroys the cancer cells and most importantly the blood vessels that supplies the cancer to grow without flooding the entire bloodstream which greatly reduces dangerous side effects. Also, the healthy tissue is not damaged and is far less invasive than removing the prostate surgically or destroying the cancer cells with radiotherapy. Another important side effect eliminated was the impact on sexual activity and urination, which diminished completely after 3 months of treatment.

Even though the tumor progresses slowly around 11,000 men die from prostate cancer in UK. The treatment is not yet available for patients but the drug firm Steba Biotech is meeting the European Medicines Agency in April to discuss applying for a safety license. This new treatment is a safe way to treat low-risk, localized prostate cancer. The laser therapy will allow more men to consider a tissue-preserving approach and defer or avoid radical therapy.

 

COPYRIGHT: This article is property of We Speak Science, a non profit institution co-fonded by Dr. Detina Zalli (Harvard University) and Dr. Detina Zalli (Imperial College London). The article is written by Argita Zalli and Kristjana Frangaj ( Cornell University, Department of Molecular Biology and Genetics)

 

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