Most cases of prostate cancer are localized, but when it spreads to other parts of the body, it’s known as metastatic prostate cancer.
The main pathway for treating metastatic prostate cancer (mCaP) focuses on starving the disease of testosterone (androgen).
In 1941, medical researchers Huggins and Hodges first showed that removing the testicles or giving estrogen could shrink tumors and improve symptoms. This work led to a Nobel Prize in physiology.
Today, hormone modulation therapy (HMT) generally involves medication. Injection therapies like degarelix or leuprolide interrupt the testosterone production signal from the brain to the testicles.
Most patients will receive one of these treatments first.
In many patients, mCaP will eventually become castrate-resistant, meaning standard HMT no longer controls the disease.
Several newer anti-androgen medications such as abiraterone, ketoconazole, and enzalutamide can then be used. It’s important to note that these medications are not standard “chemotherapy.”
Docetaxel is a standard chemotherapeutic agent traditionally used for castrate-resistant disease.
Two major trials in the mid-2010s showed a major survival benefit to patients with hormone-sensitive disease who received this agent at the beginning of HMT. It’s offered to select patients, generally in consultation with a medical oncologist.
Usually, people with mCaP aren’t offered radiation or prostate removal surgery. However, there’s ongoing research into the utility of these therapies for some patients.
Doctors consider several factors when determining the right treatment for each patient.
First, the disease is staged, usually with imaging like a:
- bone scan
- CT scan
- PET-CT scan
Second, the symptomatic status of the patient is assessed. Some people can have significant pain, mobility limitations, or urinary symptoms due to metastases or local spread.
Third, the sensitivity of the disease to HMT (castrate status) is determined. This is usually done by measuring PSA and testosterone levels.
Finally, a discussion between the patient and doctor should focus on the goals of care and treatment options available based on the above factors.
The main benefit of treating metastatic prostate cancer is to improve symptoms and prolong life. It’s important to note that, for the most part, metastatic prostate cancer can’t be cured, so the focus is more on disease management.
The side effects of HMT are not insignificant. Symptoms include:
- hot flashes
- low energy levels
- mood swings
- weight gain
- breast tenderness/growth
- loss of interest in sex
Doctors must also monitor and treat patients for:
- loss of bone density
- cardiovascular disease
There’s also emerging data on how long-term HMT can affect cognitive function, especially in older adults.
Hot flashes tend to be the most bothersome.
Non-medication strategies like keeping cool drinks with you, dressing comfortably, relaxation techniques, and breathing exercises might be helpful.
Medications, such as megestrol, estrogen therapies, antidepressants, and neuroleptic agents like gabapentin can improve hot flashes but often come with dose-limiting side effects.
Pain, although usually not a side effect of treatment, is managed with non-narcotic or narcotic pain medications. We sometimes have to manage the side effects of pain medication, such as constipation.
Using the mildest medication is always best.
Absolutely! Whenever we can avoid adding a medication but still provide a benefit, we’re doing something right.
Acupuncture has been studied by several groups as a way to alter the vasomotor (blood vessel) response of the body that causes the hot flash. Some studies suggest up to a 40 percent reduction in symptoms with an acupuncture treatment course of 5 to 12 weeks.
There has been some interest in using soy products, due to estrogen-like substances they contain. But results generally showed no significant improvement.
Multiple additional natural products and herbs have been suggested, but quality research on these is lacking. You should discuss any supplement with your doctor before adding it to your regimen.
The most important thing you can do is to stay physically active and strong. This includes following a heart-healthy diet and exercising.
Cardiovascular exercise is the most important. The degree, or intensity and duration, of cardio exercise depends on the individual person.
Several studies have pointed to a link between obesity and aggressive prostate cancer, although the mechanism is still being worked out.
Weight loss is generally encouraged if you’re overweight, but excessive or unintentional weight loss can be a sign of disease progression and should be discussed with your doctor.
Finally, if you’re a smoker, stop! If you’re finding it hard to quit, ask your doctor about products and medications that might help you.
Clinical trials are designed to answer a wide array of clinical questions. A quick search of clinicaltrials.gov shows over 150 mCaP trials currently enrolling patients in the United States.
It’s important to remember that clinical trials are often not intended to treat or cure participants, but rather to further the knowledge of the scientific community.
If you’re diagnosed with mCaP and are inclined to get involved with research, discuss it with your physician or check the site above for trials in your area.
I would add that for patients very close to the end of life, time might be better spent with family and friends.
That’s a tough one! The research and progress in treating this disease has come so far in just the past few years.
I have to say that someday, there will likely be a treatment so successful that it will effectively cure the disease. We still have a lot of work to do.
In my opinion, current research into theranostics, which incorporates targeted drug delivery with advanced imaging techniques, offers particular promise.
I also believe the key to outsmarting the disease is to stay a step ahead. This means identifying and anticipating the progression of the tumor’s escape mechanisms and preempting them.
I cannot stress enough the importance of picking the right treatment for each individual. Side effects and the expectations for disease response should be clearly discussed and understood.
That said, I am consistently amazed by what we as a medical and scientific community can do together. The huge efforts being applied to prostate cancer research hold significant promise for new and better treatment options in the near future.
Dr. Joseph Brito provides general urologic care with a special focus on minimally invasive surgical techniques and urologic oncology. Dr. Brito received his MD from George Washington University School of Medicine and Health Sciences. Dr. Brito completed a residency in urology at Rhode Island Hospital and Alpert Medical School of Brown University and trained at Yale School of Medicine in clinical oncology. Dr. Brito is a member of the American Urological Association.