Prostate cancer is a malignant tumor of the prostate gland. The prostate gland is located in the pelvis below the urinary bladder, behind the pelvic bones and in-front of the rectum (the lower part of the large bowel). Normally it produces seminal fluid that nourishes and aids in the transport of sperm. The urethra passes through the prostate gland which accounts for the urinary symptoms sometimes seen in patients with benign or malignant enlargement of the prostate.
Prostate cancer is the most common cancer in men in the United States and the second most common cause of cancer related death in this population. While the cause of this disease in unknown, each year more than 230,000 new cases of prostate cancer are diagnosed in the United States. On average one in six men will develop this form of cancer in his lifetime. Prostate cancer that is detected early and is still confined to the prostate gland has a better chance of successful treatment. The clinical behavior of prostate cancer varies widely. The majority of prostate cancers detected by screening are slow-growing and will never threaten the life of the individual or become symptomatic. Other cancers can behave aggressively with spread to other organs in the body, most commonly the bone or lymph nodes.
Symptoms of Prostate Cancer
Most prostate cancers are diagnosed when a man is asymptomatic due to a rise in prostate-specific antigen or PSA. The other way in which prostate cancer is diagnosed is when a hard nodule is found on routine digital rectal examination by the patient’s primary care physician or urologist.
Prostate cancer may not have any signs or cause symptoms in its early stages. However, prostate cancer that is more advanced may cause signs and symptoms such as:
• Trouble urinating
• Decreased urinary stream
• Urinary frequency and urgency
• Blood in the urine
• Blood in the semen
• Swelling in the legs
• Rarely difficulty with erections
• Discomfort in the pelvic area
• Bone pain
Risk Factors of Prostate Cancer
• Older age: The incidence of prostate cancer increases with age. Most cancers are diagnosed between the age of 60 and 75 years of age.
• African American: The incidence of prostate cancer is higher in African Americans than Caucasians and other ethnicities.
• Family history: Family history of prostate cancer is also a risk factor for this disease. People with one first degree relative with prostate cancer have a two-fold increased life time risk. The risk increases to four-fold if two or more relatives are affected. Some genetic syndromes as BRCA1 and BRCA2 are associated with a 1.8 times and 4.7 times increase in relative risk of prostate cancer.
• Obesity: Obese men diagnosed with prostate cancer are more likely to have advanced disease that is more difficult to treat.
How Prostate Cancer is Diagnosed
Prostate cancer is usually diagnosed by an ultrasound guided 12-14 core biopsy of the prostate gland, usually done by a urologist. The pathologist examines the biopsy specimen to confirm the diagnosis of prostate cancer and assigns a Gleason score to the tumor. A Gleason score is a measure of the aggressiveness of the tumor growth known as the grade. Gleason score is one of the prognostic factors and together with the stage of the tumor (how far the tumor has spread) and PSA level helps the doctor determine the patient risk group (low, intermediate, or high risk).
Treatment Options for Prostate Cancer at Tufts Medical Center
Treatment of localized prostate cancer
This refers to delaying treatment for newly diagnosed low-risk prostate cancer until the cancer increases in size, extent or grade with the intention of curing the patient at this point. The purpose of this approach is avoid the side effects of treatment in a cancer that otherwise may not cause symptoms or affect the life span of the individual. This usually requires monitoring the PSA, digital rectal examination periodically and planning repeat biopsies of the prostate in regular intervals, for example every year.
Surgery options are open (retropubic radical prostatectomy) or laparoscopic (robotic) approaches. The advantage of surgery is that it can achieve complete removal of tumor in most cases of localized prostate cancer. This advantage may give the patient about 95% chance of being disease free for ten years in individuals with low risk prostate cancer. Possible side effects of surgery include incontinence and impotence which are minimized with the use of nerve sparing technique employed here at Tufts Medical Center.
Radiation therapy includes both external beam radiotherapy and brachytherapy (implanting seeds in the prostate gland). The advantage of radiotherapy is that it has very good long term control of the disease and there are no randomized studies showing better outcome for surgery compared to radiation therapy. Side effects of radiotherapy though, are somewhat different than surgery. With radiation therapy, there is much less incidence of incontinence but more incidence of irritation to structures around the prostate gland such as the rectum which may cause diarrhea, and the urinary bladder which may cause urinary symptoms.
Cyrosurgery (cryoablation) destroys cancer cells by rapidly freezing and thawing cancerous tissue. This is less invasive than surgery and can often be done on an outpatient basis but is associated with a much higher incidence of impotence compared to surgery and radiation therapy.
Hormonal therapy can be used for a limited time together with radiotherapy in patients with intermediate or high risk category but should not be used alone for treatment of localized prostate cancer except in unusual cases when other options are not feasible and some treatment is required.
Treatment of Metastatic Prostate Cancer
Chemotherapy is usually used as a second line option after failure of hormonal therapy. The chemotherapeutic agent commonly used in this situation (Docetaxel or Taxotere) is given intravenously every 3 weeks and with the use of some medications is usually well tolerated. Some new molecularly targeted investigational agents are being incorporated in the treatment of patients with metastatic prostate cancer.
Other FDA-approved treatment agents include:
Cabazitaxel chemotherapy, the Sipuleucel-T (Provenge) vaccine, and denosumab and zoledronic acid to prevent bone complications such as fracture.
Programs + Services
Visit the Genitourinary Oncology Program at Tufts Medical Center which offers men comprehensive care for prostate, kidney, and testicular tumors.
Learn about innovative research conducted by Paul Mathew, MD at Tufts MC in Boston, focused on stopping prostate cancer from spreading to the bone.
The Urology Cancer Center at Tufts MC provides surgical and medical management of urologic cancers including kidney, adrenal, bladder, prostate, penile and testicular cancer.
Research + Clinical Trials
This study is being done to evaluate what effects, if any, the study drug Enzalutamide has on prostate cancer when given alone or in combination with hormonal agents Abiraterone and Prednisone. It will look at how the study drug alone compares to the study drug plus these hormonal agents in keeping the cancer from progressing.