Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer that develops in the lining of the lungs and is primarily caused by exposure to asbestos. Treatment options for MPM include surgery, chemotherapy, radiation therapy, and immunotherapy. Immunotherapy has emerged as a promising treatment option for MPM patients, but its effectiveness compared to other treatments is still a subject of debate.
Immunotherapy is a type of cancer treatment that uses the body’s immune system to identify and destroy cancer cells. Immunotherapy drugs work by either enhancing the immune system’s ability to recognize and attack cancer cells or by blocking the mechanisms that cancer cells use to evade the immune system. The two main types of immunotherapy drugs used in MPM are immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cell therapy.
Immune checkpoint inhibitors (ICIs) are drugs that block the interactions between immune checkpoints and their ligands, which can inhibit the immune system’s ability to recognize and attack cancer cells. The two ICIs approved by the US Food and Drug Administration (FDA) for the treatment of MPM are nivolumab and pembrolizumab. In a phase II clinical trial, nivolumab was found to have an overall response rate (ORR) of 18%, while pembrolizumab had an ORR of 22%. However, these response rates were not significantly different from those of chemotherapy, which has an ORR of approximately 20%.
CAR T-cell therapy is a newer type of immunotherapy that involves genetically engineering a patient’s T cells to recognize and attack cancer cells. CAR T-cell therapy has shown promising results in the treatment of blood cancers, but its effectiveness in solid tumors such as MPM is still being investigated. In a phase I clinical trial, a patient with MPM who received CAR T-cell therapy had a partial response, but the trial did not report the overall response rate.
Surgery is the primary treatment option for early-stage MPM, and it can be curative if the cancer is detected early enough. However, most MPM cases are diagnosed at an advanced stage, making surgery less effective as a treatment option. Chemotherapy is the standard treatment option for advanced-stage MPM, and it can improve survival rates and quality of life. In a randomized controlled trial, pemetrexed and cisplatin chemotherapy was found to have a median overall survival (OS) of 12.1 months, while a combination of cisplatin, pemetrexed, and bevacizumab had a median OS of 18.8 months.
Radiation therapy is another treatment option for MPM, but its effectiveness is limited due to the proximity of the cancer to vital organs such as the heart and lungs. A meta-analysis of 22 studies found that radiation therapy had a median OS of 9.4 months and a median progression-free survival (PFS) of 6.4 months.
In summary, immunotherapy has shown promising results in the treatment of MPM, but its effectiveness compared to other treatments is still unclear. ICIs have similar response rates to chemotherapy, while CAR T-cell therapy is still in the early stages of clinical trials. Surgery is the primary treatment option for early-stage MPM, while chemotherapy is the standard treatment option for advanced-stage MPM. Radiation therapy has limited effectiveness due to the proximity of the cancer to vital organs. Ultimately, the choice of treatment for MPM depends on the stage and characteristics of the cancer, as well as the patient’s overall health and preferences.
