Immunotherapy: Cancer Treatment and Side Effects

*Immunotherapy represents a significant advancement in cancer treatment, yet it's often surrounded by myths and anxiety. In this insightful interview, Peter Zombori sits down with Dr. Alexander Siebenhüner to demystify immunotherapy, explain how it works, address common misconceptions about side effects, and discuss its role in modern cancer care in Switzerland.***Peter Zombori:** Welcome, everyone, to our medical talk today. We'll be discussing immunotherapy here in Switzerland with our expert, Dr. Alexander Siebenhüner. Dr. Siebenhüner, thank you for taking the time to join us.**Dr. Alexander Siebenhüner:** Thank you, Peter, for the introduction and the invitation. I'm happy to provide my insights into the latest developments in the field of immunotherapy.**Peter Zombori:** Could you start by simply explaining what immunotherapy is? There are so many myths out there, and when speaking with potential patients, there's often a lot of anxiety, fear, and unclear communication. We would greatly appreciate a clear explanation.**Dr. Alexander Siebenhüner:** Absolutely. So, first of all, while we are talking a lot about immunotherapy now, it's actually quite an old field. What's new is that we now have the right medications to use effectively and to manage. We must emphasize that it is not comparable to the side effects of chemotherapy; it's generally well-tolerated and safe. We have been working with immunotherapies here in Switzerland for more than 15 years, and we have a very strong historical knowledge of how it interacts with tumors and how to counter potential side effects.**Watch the full video here:****Dr. Alexander Siebenhüner:** To give you some insight into how immunotherapy works: it primarily functions by **training your own immune system to detect and kill cancer cells**. Tumors grow because they cleverly hide from your immune system. Immunotherapy, especially through agents like "checkpoint inhibitors," helps your immune system recognize these tumor cells so they can be targeted and destroyed.When we discuss side effects, these are most often due to an **overstimulation of the immune system itself**. This might manifest as side effects like skin rashes or some dryness, which are typically easily managed with topical creams. Sometimes, patients might feel a little weaker or experience some tiredness, for which we monitor blood markers and can provide supportive medication if needed.In very rare cases, I must say—perhaps in about 2% of patients nowadays—we might see more significant immune-related side effects, such as toxicities to the lungs (pneumonia) or the gut system (diarrhea). However, these are managed with a step-wise approach. If we recognize any upcoming side effects, we quickly counter them at the beginning. Because of this proactive management, we generally do not see severe side effects anymore with common immunotherapies. Of course, there are some combination therapies where more awareness is needed, but typically, the treating physician works within a specialized team. Here, we have our "immune-directed team," which includes not only the oncologist but also gastroenterologists and cardiologists, to handle all possible side effects comprehensively.**Peter Zombori:** That sounds like it's much more manageable in terms of side effects than chemotherapy. Is immunotherapy nowadays the first choice to fight cancer, or are there certain limitations?**Dr. Alexander Siebenhüner:** Immunotherapy is reaching most types of cancer nowadays. In many types of cancer, especially for melanoma, immunotherapy is often the first-line treatment. In some tumors, like certain gut cancers or gastric cancers, you might initially need both a backbone of chemotherapy and immunotherapy. However, it's possible to potentially discontinue the chemotherapy within the first three months, once both treatments have initiated their effect, and continue with immunotherapy alone. In lung cancer, it's largely similar.What's essential for the effectiveness of both chemotherapy and immunotherapy are specific **biomarkers**. If we see high immune markers, which we call PDL1 and CPS, then the chances of being treated well by immunotherapy are quite high. If these markers are low, it's more likely we would discuss chemotherapy. This is getting quite detailed now, but generally, we can say that immunotherapy is making inroads into nearly all cancer types today.**Peter Zombori:** Dr. Siebenhüner, thank you so much for your time. We'll conclude here. To our viewers, if you have any more questions, please feel free to reach out to us. We'll do our best to answer, hopefully with the help of Dr. Siebenhüner. Much appreciated. We hope to speak to you on another occasion.**Dr. Alexander Siebenhüner:** Thank you, Peter.