What is Prostate Cancer?
Prostate cancer is a malignancy of the prostate gland, a structure that rests below the bladder in the male urinary tract. Patients are often asymptomatic early in the disease but may eventually develop urinary symptoms such as urinary frequency, trouble passing urine, and blood urine the urine. The cancer often spreads to the spine; therefore, patients can develop back pain as well. Risk factors for the cancer include advanced age, family history, and black race.
Most patients do not die from the cancer itself – rather most individuals die of other causes and happen to have coexisting prostate cancer. The United States Preventative Task Force does not recommend for or against prostate cancer screening and suggests that the decision be based on a discussion between the doctor and patient.
What Causes Prostate Cancer?
Prostate cancer is a malignancy of the prostate gland. In general, cancer is considered a problem with uncontrolled cell division. Cancer cells do not respond to normal regulatory signals that slow or stop cellular division in healthy cells and tissues. Uncontrolled cellular expansion can eventually result in metastatic disease – spread of the cancer to other tissues and organs. In fact, prostate cancer tends to initially spread to regional lymph nodes followed by the spine.
The most important risk factor is advanced age (age >40). Other risk factors typically include family history also African American men tend to develop this cancer at a younger age and usually have a more aggressive form of the disease.
How Common is Prostate Cancer?
Prostate cancer is common in the United States – primary care doctors frequently screen for the disease using a blood test called prostate specific antigen (PSA). The condition often requires referral to a urologist. Occasionally, the condition requires involvement of oncologists and radiation oncologists.
The annual incidence is approximately 0.1% in men their 50’s, 0.6% in men in their 60’s, and 1% in men in their 70’s. The prevalence also increases with age. Men age 31-40 have a prevalence of about 9%-31% compared to men age 71-80, who have a prevalence of approximately 31%-83%.
Signs and Symptoms
Prostate cancer is frequently asymptomatic in its early states and about 80% of men are incidentally detected by PSA screening. Patients may have urinary symptoms such as:
- Urinary frequency (polyuria)
- Burning on urination (dysuria)
- Blood in the urine (hematuria)
- Urinating frequently at night (nocturia)
- Incomplete bladder emptying
Urinary symptoms are often related to coexisting benign prostatic hyperplasia (BPH) and may not represent symptoms specific to prostate cancer. Those that have metastatic disease to the bones may complain of bone pain – particularly involving the back.
Patients may have a palpable mass or induration during examination of the prostate.
Prostate cancer screening detects most cases of prostate cancer. This is usually performed with a blood test called prostate-specific antigen (PSA). If this test is elevated, your doctor will likely repeat the study. They will also usually obtain a urine analysis to evaluate for blood in the urine. Often times, your doctor will also perform a rectal examination to feel the prostate and evaluate for any masses or irregularities.
Screening is a controversial topic as it may not lead to significant benefit in terms of morbidity and mortality. Screening may also result in unnecessary procedures or tests that are costly and potentially harmful. The US Preventative Task Force recommends that the decision to perform prostate cancer screening be a discussion between the doctor and patient.
If your PSA is elevated and you are interested in further work up of prostate cancer, your doctor will typically refer you to a urology specialist. They will discuss the risks and benefits of prostate biopsy - this procedure is typically guided with a rectal ultrasound.
Prostate Cancer Medications
Prostate cancer treatment depends on whether the cancer is localized or has spread to other tissues. Men with localized cancer and a life expectancy more than 10 years typically benefit from either radiation therapy or radical prostatectomy (surgical prostate removal).
Patients with high-risk features or those that have metastatic spread of the disease typically benefit from antiandrogen therapy – this treatment involves reducing testosterone levels either medically or surgically. Testosterone reduction is an important aspect of treatment as testosterone often fuels the growth of prostate cancer.
Medical options for antiandrogen therapy typically include:
- GnRH agonists – Zoladex (Goserelin), Vantas (histrelin), Lupron (Leuprolide), and Trelstar (triptorelin)
- Pure GnRH antagonists – Firmagon (degarelix)
- Antiandrogens – Casodex (Bicalutamide), Eulexin (flutamide), and Nilandron (nilutamide).
- Androgen inhibitors – Xtandi (Enzalutamide) and Zytiga (Abiraterone)
Some patients prefer surgical androgen deprivation – this cost-effective strategy involves bilateral removal of the testes (orchiectomy). This is less commonly performed in North America and may be associated with psychological issues.
- National Comprehensive Cancer Network (NCCN). NCCN Clinical practice guidelines in oncology. http://www.nccn.org/professionals/physician_gls/f_guidelines.asp (Accessed on May 2, 2017). - https://www.nccn.org/professionals/physician_gls/default.aspx
- Barry MJ, Nelson JB. Patients Present with More Advanced Prostate Cancer since the USPSTF Screening Recommendations. J Urol 2015; 194:1534. Pokhrel PK, Loftus SA. Ocular emergencies. Am Fam Physician 2007; 76:829.
- Winters BR, Wright JL, Holt SK, et al. Extreme Gleason Upgrading From Biopsy to Radical Prostatectomy: A Population-based Analysis. Urology 2016; 96:148. - https://www.ncbi.nlm.nih.gov/pubmed/27313123
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.