Keytruda's Role in Bladder Cancer Treatment
- The emergence of immunotherapy drugs like pembrolizumab (brand name: Keytruda) has created new possibilities that did not exist just a decade ago for people facing bladder cancer.
- Keytruda, a checkpoint inhibitor, can be used across multiple stages of bladder cancer. It may be added after surgery for high-risk cases or used to treat advanced or metastatic disease.
- While immunotherapy is not right for every patient, it represents one of the most significant advances in bladder cancer treatment in recent years.
- “Essentially immunotherapy, and specifically immune checkpoint inhibition therapy, has really changed the way we take care of bladder cancer,” Dr. Piyush Agarwal, a urologic oncologist at the University of Chicago, tells SurvivorNet.
“Essentially immunotherapy, and specifically immune checkpoint inhibition therapy, has really changed the way we take care of bladder cancer,” Dr. Piyush Agarwal, a urologic oncologist at the University of Chicago, tells SurvivorNet.
Read MoreWhat Is Keytruda?
Keytruda is the brand name for pembrolizumab, a type of drug known as an immune checkpoint inhibitor. These medicines work differently from traditional chemotherapy. Instead of directly attacking cancer cells, immunotherapy helps the body’s own immune system recognize and destroy cancer.Cancer cells often develop ways to hide from the immune system. One of the key mechanisms involves a pathway called PD-1/PD-L1, which normally helps prevent the immune system from attacking healthy tissues.
“Tumors can mask themselves so that immune cells can’t really attack them,” Dr. Agarwal explains. Checkpoint inhibitors like Keytruda block this pathway and remove that disguise.
“The immune checkpoints work by unveiling the tumors by attacking the PD-1, PD-L1 pathway,” Dr. Agarwal adds. “By doing that, it makes the tumors more susceptible to the immune system.”
In other words, Keytruda stimulates the immune system to [correctly] recognize the cancer as foreign.
Keytruda For Muscle-Invasive Bladder Cancer
Immunotherapy can be used in several different situations as part of muscle-invasive bladder cancer treatment. Doctors consider it based on the stage of disease, the patient’s overall health, and previous treatments.
It is most commonly used in the following scenarios:
- After surgery as adjuvant therapy
- As part of perioperative therapy (given around the time of surgery) with enfortumab vedotin for cisplatin-ineligible patients
- In the metastatic setting after platinum-based chemotherapy
While every patient’s situation is unique, immunotherapy has become an important part of the toolkit available to treat bladder cancer.
Adjuvant Therapy After Surgery
One of the most common uses of Keytruda in bladder cancer is as adjuvant therapy. Adjuvant treatment is therapy given after surgery to reduce the risk that cancer will return.
Doctors may recommend it when certain high-risk features are found after surgery.
Dr. Agarwal explains that the drug may be used “after bladder removal for patients who have had adverse features,” such as disease in their lymph nodes, extended to the edges of the bladder, or with what’s known as “positive margins.”
In these situations, immunotherapy can help the immune system target remaining cancer cells and potentially reduce the risk of recurrence.
The National Comprehensive Cancer Network (NCCN) notes that adjuvant pembrolizumab is “most appropriate for patients who value an opportunity to delay recurrence even if the chance of cure was not improved, and for whom the risk of side effects was acceptable.”
This reflects the AMBASSADOR trial results, which showed that adjuvant pembrolizumab significantly improved disease-free survival (median 29.6 vs 14.2 months) compared to observation in high-risk patients after radical surgery.
Clinical trials such as AMBASSADOR and other studies involving checkpoint inhibitors have demonstrated that immunotherapy can improve outcomes in some high-risk patients after surgery.
Treatment For Metastatic Bladder Cancer
Keytruda is also used for advanced bladder cancer, including cases where the disease has spread beyond the bladder. In metastatic cancer, the goal of treatment is often to control the disease, prolong survival, and maintain quality of life.
Immunotherapy has become a cornerstone of treatment for many patients in this situation.
According to the NCCN guidelines, pembrolizumab is a preferred regimen after platinum-based chemotherapy for patients with locally advanced or metastatic urothelial carcinoma.
It can be used as monotherapy or in combination with another drug called enfortumab vedotin (brand name Padcev).
Treatment For Patients Who Can’t Get Chemotherapy
Not all patients are able to receive standard chemotherapy. The most common chemotherapy regimens used for bladder cancer include cisplatin, a powerful drug that can be difficult for some patients to tolerate.
People with certain medical conditions, such as kidney disease, hearing problems, or frailty, may not be good candidates for cisplatin-based chemotherapy or other standard treatments.
In these cases, immunotherapy may offer another option.
“We also do it for patients who are too frail to undergo surgery,” Dr. Agarwal says.
For these individuals, immunotherapy can sometimes help slow the progression of the tumor and provide disease control. This approach may be especially important for patients who have limited treatment options because of other medical conditions.
The National Comprehensive Cancer Network (NCCN) recommends enfortumab vedotin-ejfv plus pembrolizumab as a preferred regimen for some patients with more advanced disease who are not eligible to receive cisplatin-based chemotherapy.
This is the only NCCN-recommended perioperative immunotherapy option for cisplatin-ineligible patients with MIBC.
Keytruda Side Effects
Like all cancer treatments, immunotherapy can cause side effects. Most patients tolerate it reasonably well, but because the drug activates the immune system, it can sometimes cause the immune system to attack normal tissues.
“These medications have an ability to really alter almost every part of your body,” Dr. Agarwal explains.
According to the National Cancer Institute, possible side effects can involve:
- Pain, swelling, or soreness at the injection site
- Fever
- Chills
- Fatigue
- Dizziness
- Nausea or vomiting
- Low or high blood pressure
Immune-related colitis, an inflammation of the colon that can cause severe diarrhea, is also a possibility.
“If you have excessive diarrhea, you can have a condition called colitis,” Dr. Agarwal explains. “If you have immune-related colitis, it can be quite catastrophic in some patients.”
Another possible complication is pneumonitis, which is inflammation of the lungs.
Although these reactions can sound alarming, severe complications are relatively uncommon.
“The incidence of severe immune-related side effects is actually pretty low,” Dr. Agarwal notes.
Doctors carefully monitor patients during treatment. That monitoring typically includes:
- Regular blood tests
- Symptom checks
- Imaging studies when needed
If immune-related side effects occur, doctors may temporarily stop the medication, treat any inflammation with steroids, and/or adjust the treatment plan.
Early detection of symptoms is important, which is why patients are encouraged to report any new or unusual symptoms to their care team.
Questions To Ask Your Doctor
- Am I a candidate for pembrolizumab (Keytruda)?
- What are the risks of adding immunotherapy to my treatment plan?
- How will I be monitored while undergoing immunotherapy?
- What type of side effects would warrant changing my treatment plan?
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