The number of men developing metastatic prostate cancer is increasing rapidly, research published in 2016 in the journal Prostate Cancer and Prostatic Diseases suggests. The number of new cases of metastatic, or stage 4, prostate cancer shot up 72 percent between 2004 and 2013, according to the Northwestern Medicine study. Overall, one in nine men in the U.S. will develop prostate cancer during his lifetime, according to the American Cancer Society. While the five-year survival rate for men with early-stage prostate cancer is nearly 100 percent, the numbers are far worse for those with a metastatic form of the disease. About two-thirds of men with metastatic prostate cancer succumb to it within five years of their diagnosis, says Dr. Sean Cavanaugh, the radiation oncology director of the CTCA Genitourinary Cancer Institute.
Here are five symptoms of metastatic prostate cancer:
-- Bone pain.
-- Urinary symptoms.
-- Swollen legs.
-- Weight Loss.
What Is Metastatic Prostate Cancer?
Metastatic prostate cancer is prostate cancer that has escaped that part of the body and spread to other regions, says Dr. Abhinav Sidana, director of urologic oncology at the University of Cincinnati's College of Medicine. When cancer cells leave the prostate, they often spread to nearby tissue such as lymph nodes but can also invade the bladder, rectum, bone, brain, liver and lungs, Sidana says. Prostate cancer found beyond the prostate is also known as advanced, or stage 4, prostate cancer.
Metastatic prostate cancer symptoms vary greatly depending on the level of the disease, Sidana says. Advanced cancer in the backbone can cause bone pain, fractures and spinal cord compression, the latter perhaps leading to leg weakness. Urinary symptoms, like difficulty urinating or voiding your bladder frequently or in small volumes is another common symptom of metastatic prostate cancer. Other signs of stage 4 prostate cancer include swollen legs, fatigue and weight loss, he says.
Pain is not only a symptom of metastatic prostate cancer but also a complication because it affects your quality of life, says Dr. Philip A. Salem, a Houston-based oncologist and author of "Defeating Cancer: Knowledge Alone is Not Enough." He served on White House health care advisory committees under Presidents George H.W. Bush and Bill Clinton. "Nobody likes pain," he says. Some patients become unable to move because of intense metastatic prostate cancer pain. Bone metastasis in stage 4 prostate cancer can also lead to neurological complications that can cause partial paralysis, Salem says. Metastatic prostate cancer can also obstruct the urethra, which can block the flow of urine from the bladder. Some patients may need a catheter inserted into their urethra, on a temporary or permanent basis, depending on how they respond to treatment.
Stage 4 prostate cancer can also spread to lymph nodes in the pelvis, Salem says. Enlarged lymph nodes can obstruct the ureter, a tube that connects the kidney, which produces urine, to the bladder. This could lead to swelling and destruction of the kidney. "It can cause serious infection, which could kill the patient," he says. In severe cases, metastatic prostate cancer can spread to the brain and cause stroke-like symptoms, he says. Metastatic prostate cancer might also lead to leg fractures in some patients, Cavanaugh says. The disease can cause a tumor to grow in, say, your femur, which can weaken the bone and lead to a break, he says. Stage 4 prostate cancer can also result in erectile dysfunction.
Hormone treatment is the primary method for treating metastatic prostate cancer, says Dr. Raj Satkunasivam, a urologic oncologist with Houston Methodist Hospital in Houston. The treatment, known as androgen deprivation therapy, involves the injection of hormones that deplete testosterone in the body. This therapy attacks cancer cells, he says. Some patients with stage 4 prostate cancer benefit from a combination of hormone treatments and chemotherapy, Satkunasivam says.
A third form of treatment, immunotherapy, enhances the immune system of the body so it can target and destroy cancer cells, Salem says. This approach is in the research stage and is promising, but more research is needed, he says.
Hormone treatment can cause an array of side effects, including impotence, decreased libido, depression, hot flashes, weight gain, fatigue and loss of muscle or bone mass, says Dr. David Y.T. Chen, director of the urologic oncology fellowship program at Fox Chase Cancer Center in Philadelphia. "It's very common for men (on hormone therapy) to have sexual dysfunction," Chen says. Chemotherapy also can have a raft of unpleasant side effects, such as fatigue, nausea, hair loss, a reduced white cell count that could make you vulnerable to infection and gastrointestinal problems like vomiting and diarrhea.
Metastatic Prostate Cancer Survival Rate
On average, 30 percent of men who are diagnosed with metastatic prostate cancer survive for at least five years, according to the American Cancer Society. Some patients with stage 4 prostate cancer can survive longer with aggressive treatment, but their quality of life will be compromised by the therapy, says Dr. Nancy Price Mendenhall, a professor of radiation oncology at the University of Florida in Gainesville. "Every patient must decide for himself what kind of intervention is best for him," she says. "He will have to weigh the risk of side effects and their impact on his quality of life with the likely effectiveness of the intervention."