Prostate
Prostate cancer is the most common cancer in men. Seed implants / brachytherapy are the best and most cost-effective treatment of prostate cancer. Texas Radiotherapy offers cutting-edge treatment including MARS and SBRT/SABR. We also perform better and safer prostate biopsies utilizing MRI-guidance and a transperineal approach.
Overview
Prostate cancer is most commonly adenocarcinoma that originates in the cells of the prostate. The prostate gland is a small walnut-sized gland that is part of the male reproductive system. The prostate produces fluid that assists the sperm in the semen. The seminal vesicles are glands behind and above the prostate gland and produce most of the ejaculatory fluid. The prostate is located beneath and behind the bladder; the prostate also sits in front of the rectum.
Prostate cancer is the most common malignancy (other than skin cancer) in men. On an annual basis, approximately 1.1 Million Men are diagnosed with prostate cancer across the world and there are over 300,000 deaths each year from prostate cancer. Typically, prostate cancer grows slowly and is often confined to the prostate gland. There are many prostate cancers that can be watched and do not require treatment. However, some cases are much more aggressive and can spread or metastasize quickly.
The prostate cells produce an enzyme named Prostate Specific Antigen or PSA. PSA is produced exclusively by prostate cells. The PSA is measured by a routine blood test. Elevated levels of PSA are often the first sign of prostate cancer. Prostate cancer that's detected early with PSA screening is highly curable.
Cancers We Treat
Symptoms
Most of the time, there are no signs or symptoms of prostate cancer. Symptoms arise when Prostate cancer is discovered at an advanced stage. These symptoms can also occur with non-cancerous conditions such as benign prostatic hypertrophy (BPH) or prostatitis.
Symptoms include:
- Difficulty starting the urinary stream
- Weak urinary stream
- Blood in ejaculate
- Pelvic discomfort
- Bone pain
- Erectile dysfunction
Risk Factors
It’s not clear what causes prostate cancer. Doctors know that prostate cancer begins when some cells in your prostate become abnormal. Mutations in the abnormal cells’ DNA cause the cells to grow and divide more rapidly than normal cells do. The abnormal cells continue living, when other cells would die. The accumulating abnormal cells form a tumor that can grow to invade nearby tissue. Some abnormal cells can also break off and spread (metastasize) to other parts of the body.
One in six men will develop prostate cancer in their lifetime. Factors that can increase your risk of prostate cancer include:
Your risk of prostate cancer increases as you age.
African Americans have a greater risk of prostate cancer than men of other races and also tend to have more aggressive prostate cancers.
Some genetic mutations associated with breast cancer (BRCA1 or BRCA2) may also be linked to higher rates of prostate cancer.
Obese men are more likely to develop advanced disease and die from prostate cancer. It is recommended to exercise most days of the week. Exercise improves your overall health, helps you maintain your ideal weight and improves your mood.
Men who consume high levels of fat are more likely to develop prostate cancer and have a more aggressive form of the disease. It is recommended that you have a healthy diet that consists of fruits and vegetables.
Screening & Diagnosis
Prostate cancer screening tests
Screening should typically begin at age 45 or earlier at age 40 if there is a family history or in African Americans.
Diagnosing prostate cancer
If a DRE or PSA test raises concerns, your doctor will likely recommend a biopsy.
Digital rectal examination (DRE)
Your doctor inserts a gloved and lubricated finger into the rectum to feel for any nodules in the prostate and to estimate prostate volume.
Biopsy
Tissue samples are typically obtained from 12 standard locations throughout the prostate.
Prostatic specific antigen (PSA)
This is a common blood test that detects a protein produced solely by prostate cells. It is elevated in prostate cancer, but also in some non cancerous conditions (BPH, infection, inflammation). It is used in the diagnosis of prostate cancer, but also during follow up after treatment to determine if the cancer is gone.
Transrectal Ultrasound-guided biopsy of the prostate (TRUS)
The most common approach to performing a biopsy is performed by using an ultrasound probe in the rectum and then samples are obtained by passing a needle through the rectal wall into the prostate. TRUS prostate biopsies are associated with an up to 7% risk of a serious infection requiring hospitalization (sepsis). In addition, antibiotics (fluoroquinolones) are typically prescribed preventatively for TRUS biopsies.
MRI-TRUS fusion Transperineal biopsy of the prostate
Due to the sepsis rates from TRUS biopsies and increasing antibiotic resistance, a different approach to prostate biopsies is becoming more common throughout the world - transperineal biopsy. In a transperineal biopsy, the needle passes from the skin below the scrotum into the prostate. Transperineal biopsies are much “cleaner” and are associated with a near zero percent chance of serious bacterial infection. Transperineal biopsies can be performed with sedation in an operating room or in the office with local anesthesia (lidocaine prostate block).
With this technology, MRI images are fused with the TRUS image to identify suspicious lesions noted on MRI in the prostate for biopsy. This technique is more accurate in identifying aggressive disease than standard biopsy. Additionally, transperineal biopsies can reach parts of the prostate that are nearly impossible to reach during a transrectal biopsy. In addition, patients report less discomfort with transperineal as opposed to transrectal biopsies.
In some instances, CT scan, bone scan or PET scan may be requested for staging purposes, i.e. to determine if there are signs of cancer spread. These tests are usually only requested for patients with more aggressive disease (unfavorable intermediate or high-risk).
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Gleason’s score
When a biopsy confirms the presence of cancer, the Gleason’s score determines the level of aggressiveness of the cancer cells or the Grade. The score is comprised of the primary cellular pattern + the secondary pattern or appearance of the cells. Each pattern is scored from 1 to 5, with 1 being least aggressive and 5 being most aggressive. Prostate cancers are actually scored from 6 - 10. Gleason’s 6 cancers are low grade, 7 is intermediate and 8 and above are high grade.
Risk Groups
A patient’s risk group is more important than Stage (NCCN) for most prostate cancer experts. Risk groups are determined by PSA, clinical stage and Gleason’s score. Groups range from very low to very high.
Low risk - PSA < 10, Gleason’s 6, Clinical stage T2a or less.
Intermediate risk - PSA 10-20, Gleason’s 7, T2b-2c.
High risk - PSA >20, Gleason’s 8 and above, T3a or higher.
Treatment Options
Your prostate cancer treatment options depend on your overall health and your risk group classification. There are only three acceptable options of treatment for localized prostate cancer: Active surveillance, surgery and radiation therapy.
Active Surveillance
Your prostate cancer treatment options depend on your overall health and your risk group classification. There are only three acceptable options of treatment for localized prostate cancer: Active surveillance, surgery and radiation therapy. Side effects unfortunately include fatigue, mood changes, hot flashes, weight gain, loss of libido and inability to have erections.
Surgery to remove the prostate
Surgical treatment for prostate cancer involves removing the entire prostate, the seminal vesicles and sometimes also some lymph nodes in the pelvis. There are two types of prostatectomies: open and robotic-assisted. Most are robotic assisted currently. Radical prostatectomy carries a risk of urinary incontinence and erectile dysfunction.Side effects unfortunately include fatigue, mood changes, hot flashes, weight gain, loss of libido and inability to have erections.
Radiation therapy or radiotherapy
Radiation therapy uses high-powered energy to kill cancer cells. Prostate cancer radiation therapy can be delivered in two ways:
Externally (External Beam Radiation Therapy - EBRT)
During external beam radiation therapy, you lie on a table while a machine moves around your body, directing high-powered X-rays to your prostate cancer. You typically undergo external beam radiation treatments five days a week for typically 8-9 weeks or for 5 weeks if combined with brachytherapy. Modern day techniques include IMRT and VMAT.
Alternatively, a technique called Stereotactic Body Radiation Therapy (SBRT) or Stereotactic Ablative Radiotherapy (SABR) can be used. This involves typically 5 days of treatment over two weeks time delivering much higher daily doses of radiation therapy. Many machine platforms have such capabilities including the Radixact.
Proper targeting of the prostate is important since the prostate is shifted day-to-day by differences in fullness of the bladder and rectum. In order to account for the position changes, gold fiducial markers are placed into the prostate so that x-ray images can localize the markers and ensure accurate radiation therapy.
Internally (Brachytherapy)
Brachytherapy involves placing many rice-sized radioactive seeds in the prostate gland under ultrasound guidance. The radioactive seeds deliver high doses of radiation to a very confined region and thus the much higher doses of radiation therapy can be delivered than with any other technique. Since higher doses can be delivered with brachytherapy than with any other means, brachytherapy is the “Gold Standard” of radiation therapy for low- and favorable intermediate-risk patients (monotherapy = brachytherapy alone) or in combination therapy (brachytherapy plus external beam radiation therapy, EBRT) in unfavorable intermediate- or high-risk patients).
A recent clinical trial (ASCENDE-RT) concluded that intermediate- or high-risk patients that received combination therapy were twice as likely to have PSA control of their cancers than patients who received EBRT alone. (https://doi.org/10.1016/j.ijrobp 2016.11.026)
Side effects of radiation therapy can include painful, frequent or urgent urination, as well as rectal symptoms such as loose stools or pain when passing stools. Erectile dysfunction can also occur.
MRI-assisted Radiosurgery (MARS)
At Texas Radiotherapy, we perform MARS, which is the next generation of prostate seed implants. MRI imaging is utilized to design and guide the placement of the radioactive seeds during the implant procedure, which leads to better and safer seed implants than without MRI-assistance.
Hormone therapy
Hormone therapy or androgen deprivation therapy (ADT) is often used in combination with radiation therapy. ADT is a treatment to stop your body from producing the male hormone testosterone, which the prostate cancer cells use as “food”. ADT is commonly given as injections that typically last anywhere from 1 - 6 months or in pill form. ADT temporarily puts the prostate cancer to sleep. It also will shrink the size of the prostate and it works in conjunction with radiation therapy to improve treatment results. Side effects unfortunately include fatigue, mood changes, hot flashes, weight gain, loss of libido and inability to have erections.
Comparing Treatments
For an objective, easy to use and interactive comparison of treatment results for all treatments of localized prostate cancer by risk group, view The Prostate Cancer Results Study Group at www.prostatecancerfree.org. This is a comparison of all available studies published in the literature which are updated annually and organized by well-respected Radiation Oncologists and Urologists. The Disease-Free Survival (DFS) is analyzed by Risk Group (Low, Intermediate, and High). For each of the Risk Groups, the DFS for patients treated with Brachytherapy alone in low risk patients, or combined with External Radiation and/or Androgen Blockade for intermediate- and high-risk patients, is superior to any of the other treatments, including Radical Prostatectomy and External Radiation.
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Making Radiation Therapy Safer
SpaceOAR hydrogel
SpaceOAR is a bioabsorbable hydrogel that is implanted between the prostate and the rectum and the gel moves the rectum 5-10 mm from the prostate. Typically, the prostate and rectum are only separated by a tiny layer of fat. Therefore, even with the most advanced forms of radiation treatment, a small sliver of rectum receives the highest doses of radiation therapy.
By adding “Space” between the prostate and rectum, the highest doses of radiation therapy instead occur in the gel and the dose that then reaches the rectum is dramatically reduced. The doses to the erectile structures are also reduced. This procedure allows modern day radiation therapy to be even safer and results in dramatically less complications.
