Uterine Cancer Treatment: Immunotherapy

Conventionally, uterine cancer is managed through surgery, radiation therapy and chemotherapy. While these treatment methods are effective, they have shown limited success in treating more advanced or more aggressive forms of the disease. Immunotherapy has recently emerged as a novel and promising approach to treat uterine cancer. Understanding the evolving role of immunotherapy in uterine cancer is important in making informed decisions with regards to the most suitable treatment plan for you.

The immune system is the body’s defence network, designed to protect the body against infections and diseases. It comprises specialized cells, tissues and organs that work together to detect and neutralize harmful threats to the body. However, cancer cells are able to avoid being recognized and targeted by the immune system through various mechanisms, such as:

• Genetic mutation to evade immune cell detection.
• Surface proteins to deactivate immune cells.
• Modification of healthy cells within the tumor’s microenvironment to hinder the immune system’s response against cancer.

Immunotherapy helps to overcome the immune evasion mechanisms of cancer cells. It achieves this by strategically leveraging one’s own immune system to target and kill cancer cells. In the case of uterine cancer, this form of treatment is commonly administered through immune checkpoint inhibitors.

Immune checkpoint proteins are expressed on the surface of immune cells. They are responsible for controlling immune responses. Each immune checkpoint protein has a specific target which they can bind to, known as a partner protein. The binding of immune checkpoint proteins to their partner proteins signals to the body to suppress the immune response. This is important in ensuring that immune responses within the body remain properly regulated.

Immune checkpoint inhibitors (ICIs) are drugs that function to block these immune checkpoint proteins. This allows for a stronger immune response against cancer cells. They are typically administered intravenously (IV) once every few weeks.

There are 2 main target proteins for the treatment of uterine cancer — programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1). PD-1 is a common immune checkpoint protein found on the surface of immune cells. PD-L1 is the partner protein of PD-1, which binds to PD-1 to suppress the immune response. By blocking either one of these proteins, ICIs are able to trigger a stronger immune response against the cancer cells.

PD-1 inhibitors

PD-1 inhibitors are commonly used in immunotherapy to treat many types of uterine cancer. Common drugs belonging to this class include pembrolizumab, dostarlimab and nivolumab. In general, these drugs can be given alone or together with other forms of treatment, such as chemotherapy. Additionally, pembrolizumab is typically used to treat uterine cancer tumors which are highly mutated.

PD-L1 inhibitors

On the other hand, PD-L1 inhibitors are generally used to treat endometrial cancer. The most common PD-L1 inhibitors used are durvalumab and avelumab. In particular, durvalumab is usually used to treat advanced or recurrent cases of uterine cancer. Similar to PD-1 inhibitors, these drugs can be administered alone or in combination with other treatment methods.

Immunotherapy has shown promise in the treatment of uterine cancer, especially for advanced or recurrent cases of the disease. It is also known to be effective in treating cases of uterine cancer when other traditional treatment methods such as chemotherapy have failed.

Immunotherapy is also effective when administered in combination with other forms of treatment. For instance, immunotherapy given together with chemotherapy has shown to improve survival rates in patients with metastatic uterine cancer. Furthermore, compared to traditional cancer treatment methods, immunotherapy generally has fewer and less severe side effects.

However, immunotherapy is not suitable for all patients. Immunotherapy is only effective for patients whose cancers have certain biological features which make them more responsive to this treatment method. Moreover, immunotherapy is still currently an active area of research. There are only a limited number of immunotherapeutic drugs approved by the US Food and Drug Administration (FDA) that can be used. The high costs of this treatment may also serve as a potential barrier for many patients. For these groups of patients, other treatment methods may be more suitable.

Although it is effective, immunotherapy is also associated with its own set of side effects. Commonly reported side effects include, but are not limited to:

• Fatigue
• Nausea
• Diarrhea or constipation
• Loss of appetite
• Pain in the muscles or joints
• Shortness of breath

Even though severe side effects are rare, they may still arise. These include:

• Adverse reaction to infusions: ICIs are given as IV infusions and this may result in an allergic response. This may manifest itself as a fever, rash, nausea and breathing difficulties.
• Autoimmune reactions: ICIs function by inhibiting one of the immune system’s regulatory checkpoints. While this enhances the immune response against cancer, it may also cause the immune system to target healthy tissues in the body. This may result in serious or even life-threatening conditions.

It is important to look out for these side effects and to ensure that they are promptly reported to your healthcare provider should they arise.