Prostate cancer is a major public health issue, affecting an estimated 1.3 million people worldwide and causing more than 360,000 deaths per year. In the U.S. alone, experts predict around 290,000 new cases in 2023, and over 35,000 deaths.
Early-stage prostate cancer is highly treatable, with a five-year survival rate close to 100%. But advanced, or stage 4, prostate cancer is much harder to treat. The five-year survival rate for metastatic prostate cancer is less than 30%.
One promising treatment approach is immunotherapy. Immunotherapy drugs leverage your own immune system to fight cancer cells, and several options are either approved or under investigation as a treatment for stage 4 prostate cancer.
Understanding Immunotherapy and its Mechanisms in Prostate Cancer
Immunotherapy is a type of cancer treatment that helps your immune system fight the cancer. It doesn’t attack the cancer directly. Instead, it “supercharges” your body’s natural defenses so they can recognize and destroy cancer cells. That’s different from traditional treatments like chemotherapy and hormone therapy.
How Immunotherapy Works
One of the key players in your immune system is the T cell. Sometimes, proteins prevent T cells from attacking cancer. Immune checkpoint inhibitors work by blocking those proteins and freeing up the T cells to do their job.
Types of Immunotherapy Used in Prostate Cancer
There are a couple of main types of immunotherapy used for prostate cancer:
- Cancer Vaccines: These vaccines, like Sipuleucel-T (Provenge), use your own immune cells to target prostate cancer. Doctors collect your immune cells, modify them, and then infuse them back into your body.
- Immune Checkpoint Inhibitors: Drugs like Pembrolizumab (Keytruda) and Dostarlimab (Jemperli) block the proteins that stop the immune system from attacking cancer cells. This allows the immune system to work more effectively.
FDA-Approved Immunotherapy Options for Stage 4 Prostate Cancer
While research continues to explore the potential of immunotherapy in treating stage 4 prostate cancer, there are currently a few FDA-approved options available.
Sipuleucel-T (Provenge®)
Sipuleucel-T, often referred to by its brand name Provenge, is a cancer vaccine specifically approved for metastatic castration-resistant prostate cancer (mCRPC). Unlike traditional vaccines that prevent disease, Sipuleucel-T is designed to stimulate the immune system to recognize and attack existing prostate cancer cells.
The treatment involves a series of infusions, typically three in total, spaced two weeks apart. Each infusion can take an hour or longer to administer.
Immune Checkpoint Inhibitors: Pembrolizumab (Keytruda®) and Dostarlimab (Jemperli®)
Pembrolizumab (Keytruda) is another immunotherapy drug that has received FDA approval for use in prostate cancer, but with a specific caveat. It’s only approved for prostate cancers that exhibit particular genetic features, namely tumors with high microsatellite instability (MSI-H) or mismatch repair deficiency (dMMR).
The infusion schedule for Pembrolizumab is generally every three to six weeks, with each infusion lasting around 30 minutes.
Dostarlimab (Jemperli) is another immune checkpoint inhibitor that targets tumors with dMMR. The treatment schedule involves infusions every three weeks for the first four doses, followed by maintenance treatments every six weeks. Like Pembrolizumab, Dostarlimab infusions typically take about 30 minutes.
Clinical Trials and Emerging Immunotherapy Approaches
The Role of Clinical Trials
Clinical trials are vital for developing new and improved immunotherapy treatments. They also provide patients access to cutting-edge therapies that aren’t yet widely available.
Research Areas and Targets
Researchers are studying different proteins and pathways to see if they can be targeted by immunotherapy. For example, the CT10/MAGE-C2 cancer-testis antigen is often expressed in advanced prostate cancer. Other targets include proteins that inhibit androgen receptor target genes and regulate macrophage inflammation.
The Cancer Research Institute (CRI) is a major funder of prostate cancer research. It has provided almost 100 grants, totaling almost $25 million. The CRI’s research focuses on advancing clinical trial opportunities.
If you’re interested in participating in a clinical trial, talk to your doctor. They can help you determine if a clinical trial is right for you.
Potential Side Effects and Management
Because immunotherapy works by activating your immune system, it can cause a range of side effects. Some common ones include flu-like symptoms such as fever, chills, and fatigue. Infusion reactions are also possible.
The good news is that most side effects are manageable and usually resolve within a few days. Your healthcare team will provide support to help you manage these effects.
It’s crucial to openly communicate with your medical team. Talk to your oncologist about any concerns or side effects you experience.
Frequently Asked Questions
Can a man live 10 years with metastatic prostate cancer?
It’s definitely possible. While every case is different, some men with metastatic prostate cancer do live for 10 years or more. Factors like overall health, the specific characteristics of the cancer, and how well it responds to treatment all play a role.
When a doctor says weeks to live…
Hearing a doctor say “weeks to live” is incredibly difficult. It generally indicates that the cancer is very advanced, and treatments are no longer effective. However, it’s crucial to discuss palliative care options to manage symptoms and improve quality of life during that time. It’s also worth seeking a second opinion, although it’s important to be realistic about the prognosis.
How fast does stage 4 prostate cancer spread?
The speed at which stage 4 prostate cancer spreads varies significantly. Some cancers may grow and spread relatively slowly over years, while others can progress more rapidly. Regular monitoring and imaging are essential to track the cancer’s progression and adjust treatment accordingly.
Can you fully recover from stage 4 prostate cancer?
Unfortunately, a full recovery from stage 4 prostate cancer is rare. However, that doesn’t mean there’s no hope. Treatments like hormone therapy, chemotherapy, radiation, and immunotherapy can help control the cancer, extend life, and improve quality of life. It’s more about managing the disease than curing it completely.
Who is the longest survivor of metastatic prostate cancer?
It’s tough to pinpoint a single “longest survivor” because medical records aren’t always publicly available. However, there are documented cases of men living with metastatic prostate cancer for well over 20 years with ongoing treatment and management. These individuals often participate in clinical trials and benefit from advancements in cancer care.
Final Thoughts
Immunotherapy is a promising advancement in the treatment of advanced prostate cancer. It may give hope to people who haven’t responded to other treatments.
Research and clinical trials continue to improve immunotherapy approaches. Talk with your oncologist about whether immunotherapy is right for you.