Metastatic prostate cancer: What you need to know
Sometimes, prostate cancer develops quickly and spreads to other organs. This is known as stage IV prostate cancer and is said to be metastatic.
What is the prostate?
The prostate is a small organ that plays a role in protecting sperm and producing semen.
The prostate gland is a small, walnut-shaped organ that sits between the bladder and rectum in men.
During ejaculation, sperm cells travel from the testicles through the seminal vesicles to the prostate gland. The prostate secretes special fluids that help the sperm cells survive.
This combination of fluid and sperm cells is known as semen, and it exits the body through the urethra.
What is metastatic prostate cancer?
In many cases, prostate cancer grows very slowly; so slowly in fact, that many men do not even know that they have the disease. In other men, however, the disease metastasizes — spreads to organs outside of where it originated.
There are two types of metastatic prostate cancer:
- Local metastasis: Prostate cancer with local metastasis means that the cancer has spread to other organs within the pelvis. This usually means the local lymph nodes, but can include any organ or structure in the pelvis.
- Distant metastasis: Distant metastasis means that the prostate cancer has spread beyond the pelvis. The bones, spine, brain, liver, and lungs are common sites of cancer metastasis.
Potential symptoms of prostate cancer include difficulty urinating, pain during urination, and a sense of needing to urinate urgently.
Symptoms of prostate cancer can include:
- urinary urgency
- difficulty starting or stopping urination
- weak or interrupted urine flow
- painful or burning urination
- erectile dysfunction
- painful ejaculation
- blood in the urine or semen
Anyone experiencing these symptoms should consult with their doctor as soon as possible. While many other conditions can cause similar symptoms, it is important to rule out prostate cancer.
Once a person has been diagnosed with prostate cancer, the signs of metastasis will vary depending on the where the cancer spreads and how quickly it is growing.
For example, a person with prostate cancer and local metastasis to nearby lymph nodes may not experience any change in symptoms.
However, a person with metastasis to the bones may experience bone pain.
Other symptoms of metastasis may include:
- feeling unwell
- reduced appetite
- weight loss
- swelling in the legs or feet
Advanced prostate cancer can cause many other health problems depending on where the cancer has spread to and how quickly it is spreading.
- Urinary problems: Cancerous growths can press on the bladder, urethra, or other pelvic organs. Prostate cancer can also spread to those organs and cause urinary retention, blood in the urine, incontinence, and difficulties emptying the bladder.
- Bowel problems: Advanced prostate cancer can cause bowel problems, such as constipation, diarrhea, urgency, obstruction, and incontinence. This is often due to the use of pain medications, or the spread of prostate cancer to the bowel or rectum. Dietary changes, dehydration, and inactivity can also cause bowel problems.
- Sexual problems: It is not uncommon for men with advanced prostate cancer to have difficulties getting or maintaining an erection. Some men also have decreased libido or an inability to ejaculate.
- Bone pain or fractures: Prostate cancer that has spread to the bones can cause significant bone pain. It can also weaken the bones, making a person susceptible to breaks and fractures.
- Hypercalcemia: Calcium is stored in the bones but can leak out into the blood if prostate cancer spreads to the bones. High levels of calcium in the blood can cause fatigue, increased thirst or need to urinate, nausea and vomiting, constipation, and loss of appetite.
- Anemia: Anemia means a decrease in the number of red blood cells that are available to carry oxygen throughout the body. This can lead to severe fatigue, shortness of breath, and looking pale. It is usually caused by cancer that has spread to the bone marrow but can also be a side effect of cancer treatments.
- Lymphedema: Prostate cancer that has spread to the lymph nodes can cause blockages within the vessels that transport lymph around the body. This causes swelling in the legs or scrotum.
There are many types of treatments available for advanced prostate cancer. A doctor or oncologist will develop a treatment plan that takes into account the individual's symptoms, prognosis, goals for treatment, age, and general health.
Hormone therapy for advanced prostate cancer shuts down the production of male sex hormones. This can help prevent the cancer from continuing to grow. Common drugs include abiraterone (Zytiga) and enzalutamide (Xtandi).
Chemotherapy is a type of medication that destroys cancer cells or prevents them from multiplying. People are usually given chemotherapy once the prostate cancer has stopped responding to hormone therapy.
Chemotherapy is usually a combination of two or more drugs that are administered intravenously, injected, or taken as a pill.
Immunotherapy is a type of medication that modifies the body's immune system to find and destroy cancer cells.
Treatment for prostate cancer that has spread to the bones includes drugs such as zoledronic acid (Zometa) and denosumab (Xgeva). Treatment for local metastatic cancer may also include radiation therapy.
Side effects of prostate cancer treatment
Prostate cancer treatment can cause some serious side effects, including:
Prostate cancer treatments may cause a number of side effects that should be outlined by a medical professional beforehand.
- urinary incontinence
- urinary retention
- erectile dysfunction
- hair loss
- loss of appetite
- nausea and vomiting
Luckily, there are many medications available to treat the side effects of cancer treatment.
A person should not feel the need to "power through" or suffer from uncomfortable symptoms. It is important for anyone undergoing treatment to communicate with their healthcare team about any side effects they are experiencing.
The prognosis for advanced prostate cancer depends on where the cancer has spread and how aggressively it is growing.
According to the American Cancer Society, survival rates are as follows:
- Local prostate cancer without spread has a 5-year survival rate at nearly 100 percent.
- Prostate cancer with local spread also has a 5-year survival rate at nearly 100 percent.
- Prostate cancer with distant metastasis has a 5-year survival rate of around 29 percent.
These are general statistics; it is important for a person with prostate cancer to speak to their doctor about their specific case.
If prostate cancer is diagnosed before it has spread, or if it has only spread to nearby structures, the survival rate is excellent.
This makes routine screening and early diagnosis essential in the fight against prostate cancer.
Men over the age of 50 should speak to a healthcare professional about the different screening options and which one is most appropriate for them.