Q&A: Why Oncologist-Dermatologist Collaboration is Essential for Managing Systemic Mastocytosis

Hussein Abbas, MD, PhD, of MD Anderson Cancer Center in Houston, Texas, sat down with Dermatology Times following his session at the SDPA Fall 2025 Conference to discuss the diagnostic challenges of systemic mastocytosis and the vital role dermatologists play in multidisciplinary care. In this Q&A, Abbas highlights key pearls for recognizing and managing this complex disease and emphasizes the importance of collaboration between dermatologists and oncologists to optimize patient outcomes.

DT: What were the biggest takeaways and key pearls from “When a Rash Is More than Skin Deep: Systemic Mastocytosis Essentials?”

Abbas: I think one of the main challenges of skin disease that involves systemic mastocytosis is the delayed time for diagnosis. It takes, on average, 8 years from the time a patient starts having symptoms until they see systemic mastocytosis specialists, and that's because of the confusion of the disease and how it overlaps with so many other entities. So the main thing physicians or practitioners usually see initially is a skin rash in almost 70% of the patients and this rash can be biopsied and then maybe lead to this diagnosis of cutaneous mastocytosis. I think the key thing here to recognize is that an adult patient with a diagnosis of cutaneous mastocytosis needs to have workup to rule out systemic mastocytosis, which means the disease is not just in the skin, it's actually somewhere else as well. In fact, almost all adult patients - I say 100% but there are always exceptions - but almost all of them who have cutaneous mastocytosis will have bone marrow involvement at some point in their life. And that's important, because once it is coming also from the bone marrow, it may affect other organs. We need to stage it correctly, and we need to treat it appropriately based on approved therapies or research studies, etc. And that's why the distinguishing feature of once you know it's cutaneous, refer to a place where they can really manage or even diagnose systemic mastocytosis, because the diagnosis of systemic mastocytosis is itself complicated and requires really a lot of expertise and special testing to confirm it.

DT: What do you want dermatologists to know about your role as an oncologist?

Abbas: I do think that the key thing to note is that patient care is a multidisciplinary care. I don't think it should be in silos. I don't think it should be in a single discipline. As an oncologist and hematologist, I count a lot on my colleagues in hematopathology, for example, to recognize the disease. I often send patients from my clinic to dermatology to rule out, for example, if we have CLL, one type of chronic leukemia, they have a higher risk of cancers. We actually send them to dermatology, because they really are the experts in getting the right earlier diagnosis, also for systemic mastocytosis...We really need their help. Because first of all, dermatologists are usually the first to see, not always, but commonly first to see this disease or try to see signs of it. Because when patients usually get a complaint of skin findings, they go see a dermatologist. So their recognition of that and their communication with physicians who are comfortable managing systemic mastocytosis is very important. And to be honest, there are few physicians and not that many physicians that actually know systemic mastocytosis or treat systemic mastocytosis. So going to resources to identifying where the physicians are within their network would be very important. And for us as oncologists, again, we count on them to help guide some of the management, especially when we can get these skin findings under control by the therapies that we get these patients.

DT: What do you think makes a relationship between a dermatologist and an oncologist so successful?

Abbas: I think putting the patient first is number one, making sure that decision-making is shared and based on the patient's priority. Patients don't want to receive conflicting information from different physicians. So they really want to have a complementary approach for the care toward their symptoms, rather than everybody is managing things in isolation. For instance, if a dermatologist is prescribing a certain drug and an oncologist is prescribing another drug, we want to make sure these drugs are not interacting. So communication becomes key and access to shared decision making becomes key. And this is something we do I think pretty reasonably when patients are referred to us, or when referred to them. There's a communication when we start or stop medications and when it's appropriate or not. So I think especially now with the era of electronic medical records, where a lot of physicians do have access to some of these discussions with the patients. Because it's documented, then they're able to build decision-making according to that. So what I think makes it so successful is putting the patients first, which I think is every doctor's intention, and then really deciding, does every patient need treatment or not? Because even with systemic mastocytosis, cutaneous mastocytosis, or any of the manifestations of mastocytosis, not every patient needs treatment. Some patients may not feel the need to be treated. So that's very important so we're not over-treating but also recognizing it is important.

[This transcript has been edited for clarity.]