How leukemia escapes the body’s immune defenses

Imagine if some tricky cancer cells could sneak out of their usual hiding places and set up shop somewhere else in the body. That’s exactly what happens in a special kind of blood cancer called extramedullary acute myeloid leukemia, or eAML. Most people know leukemia as a disease that starts in the bone marrow, where our blood is made. But sometimes, these cancer cells travel to places like the skin or organs, making the disease even harder to spot and treat. A recent study published in the Blood Cancer Journal (Genomic and immunogenomic profiling of extramedullary acute myeloid leukemia) helps us understand how these cells manage to escape and hide from our body’s natural defenses.

What is extramedullary AML and why does it matter?

With regular acute myeloid leukemia (AML), cancer cells mostly stay in the bone marrow. In eAML, though, they break out and invade other tissues. Doctors have known about this for a while, but it was thought to be pretty rare. Now, thanks to better scanning techniques, we know that eAML might be much more common than previously believed—possibly affecting over 1 in 5 patients. That matters because eAML can behave differently and may need special care. Yet, many guidelines don’t offer extra advice for spotting or treating it.

How do leukemia cells escape the immune system?

Our immune system acts like a security guard, always on patrol for intruders. Cells have special identity tags, called HLA molecules, that help the immune system recognize what belongs and what doesn’t. The new research found that eAML cells often lose or change these tags, especially in parts called class II HLAs. Without these, the immune system has a much harder time noticing and attacking the cancer cells, so they can slip away and grow in new places. This is similar to what happens in some patients after a bone marrow transplant, where new immune cells are supposed to fight any leftover leukemia but sometimes get tricked by these missing tags.

Are there special gene changes in eAML?

The study looked at both regular bone marrow cancer cells and those from other tissues in 26 patients. Surprisingly, the cancer cells outside the bone marrow often had different gene mutations than those still inside. One important gene, called FLT3, had more changes in eAML cells, especially when the cancer came back after treatment. Other genes, like those in the RAS pathway, were also more common in patients with eAML. These gene changes can make the cancer cells stronger and better at moving to new places.

Why does this matter for treatment?

Because eAML cells can be different from regular leukemia cells, it’s important for doctors to test them separately. Sometimes, the mutations in eAML cells offer clues to treatments that might work, but these could be missed if doctors only look at bone marrow samples. The study suggests that screening for eAML should be part of regular care, especially since early clues can help doctors choose the best therapies. For example, knowing about FLT3 or RAS mutations may help guide new treatments tailored to each person—a trend that’s becoming more common thanks to health AI tools, as explained in this SlothMD article on personalizing cancer care.

What does this mean for patients and families?

For those facing AML, these discoveries bring hope for more precise and effective treatments. By understanding how cancer cells hide from the immune system and change their genetic makeup, doctors can look for warning signs earlier and pick medicines that target the right mutations. This is especially important for cancer survivors, as past treatments like chemotherapy can change the types of blood stem cells in the body, as discussed in this SlothMD article on chemotherapy’s effects. The more we learn about each person’s cancer, the better we can use tools like health AI and new genetic tests to plan the right care.

The future of leukemia research

The study’s findings, along with data now available in a public research database (figshare dataset), show that cancer is always finding new ways to outsmart the body. But with advanced genetic testing, improved imaging, and smarter use of health AI, doctors are getting better at keeping up. For families and patients, this means more hope for early detection, personalized treatments, and better outcomes. Staying up to date on these discoveries, perhaps by exploring resources like SlothMD, can help everyone make more informed decisions about their health.