laBCC: Cemiplimab Safety Monitoring
Insights into cemiplimab treatment monitoring and management in locally advanced basal cell carcinoma (laBCC).
Anna C. Pavlick, D.O.: These medicines will also get metabolized through the liver and the kidneys. Before we would infuse a medicine to a patient, we would always check their blood work to make sure that their liver and their kidneys are functioning well and that it is safe for us to infuse them with this medicine. Finally, there are impacts on endocrine organs. Endocrine organs are essentially the organs in your body that make hormones.
We know that immunotherapy can impact or cause inflammation to certain endocrine organs, the most common being the thyroid gland. The thyroid is found in your neck. It regulates your metabolism, and if we cause an inflammation of your thyroid gland, many times what will happen is the thyroid will increase your metabolism. Patients will come in and say, “Doc, I have not changed anything but I am eating. I feel good. But I am just losing weight.” Then we check their thyroid function, and we find out that they have now what we call hyperthyroidism, so their thyroid is working overtime. The faster your thyroid works, the faster your metabolism is, and the more that you are more prone to losing weight.
What usually happens is that thyroid gland gets tired, those cells get tired of working overtime, and then they just burn out. If that happens, patients will then go from having hyperthyroid to hypothyroid. Patients who have hypothyroidism have very slow metabolisms, and so they really have no appetite but they are gaining weight. They can get swelling around their eyes, they can get swelling of their body, they can get constipated, and their hair can get very dry and cracked. Those symptoms are a classic presentation of hypothyroidism.
Thyroid disease is very easy for us to monitor because every time a patient comes into our office and gets their blood work done before they get their infusion of cemiplimab [Libtayo], we check their thyroid function. If it looks like it is creeping into the hypothyroid range, I will tell my patients, “Listen, it looks like we might be affecting your thyroid. We may need to provide you with a medicine called levothyroxine, which is a thyroid supplement that you will need to take, so that we can keep your metabolism where it’s supposed to be.”
What is important to know about these endocrine issues or these hormone-producing glands is that once they shut down, we have pretty much shut them down forever. If you develop hypothyroidism, your thyroid gland is probably not going to recover. You are most likely—and I say that because nothing is ever perfect—most likely you are going to need to take a thyroid replacement pill, a tiny, little pill every morning called levothyroxine to make sure that your metabolism is where it is supposed to be. That happens very, very rarely, but it is the most common of the endocrine organ dysfunctions that we can cause. There are other endocrine dysfunctions that we can cause with checkpoint inhibitors, and those are what are called adrenal insufficiency, hypophysitis, or we can even make patients into insulin-requiring diabetics because the islet cells, or the cells within the pancreas gland that make insulin, get burned out.
These are extraordinarily rare side effects, but I make it a point to make sure I tell every patient that although they are extraordinarily rare, you need to understand that they can happen, and I cannot predict to whom it is going to happen. In the event that something like this happens, patients are prepared and are willing to now take hormone supplements, whether it be levothyroxine, hydrocortisone or insulin to support their body’s functioning, because they are all required hormones that every person needs to manufacture or take externally in order to function every day.
This is a good medicine, a great medicine, and it has made major differences in how we treat patients, but everything has pros and cons and patients need to understand what those pros and cons are, so that they can give us what we call informed consent or they understand and say, “Yes, I understand that there are risks. However, I think the benefit of taking this medicine by far outweighs any risks that I have talked about. If those side effects happen, I understand that I may be committed to taking another type of a pill or insulin for the rest of my life with the benefit of getting my cancer under control.” It is a complicated picture, but, in general, with a low risk, most patients say, “Yeah, I think it is worth the risk because I really want my cancer better controlled.”
Transcript edited for clarity.
