How does chemotherapy work in treating ALL and what are some common chemotherapy drugs used?

r, solid cancers we used vincristine, which is used again in many other diseases. We also use cyclophosphamide. We use methotrexate. And we use cytarabine. Those are just an array of some of the many, options that we use.

We use a lot of steroids. Those are not chemotherapies, but those are very toxic to the lymphoid blast. These lymphoid leukemia cells. So those are incorporated into almost almost all regimens.

One unique thing I'll say about ALL as well is that all patients receive preventive chemotherapy, not just in the veins but into the spine. And we call that intrathecal chemotherapy. In most patients, it's administered directly to the spine through lumbar puncture. So some patients also receive it through something called an ommaya reservoir, which is a little way that we can administer the chemotherapy, through a device that's, inserted under the scalp. The main chemotherapies we, use into the spinal cord or through that ommaya or methotrexate and cytarabine. They're given at very low doses. And the goal of that is to prevent disease from going into the, brain space, which is a common, occurrence in ALL.

Broadly, the goal of chemotherapy in patients with acute lymphoblastic leukemia is to kill the rapidly dividing cells through a number of different mechanisms. The treatment of children with ALL generally consists of 3 or 4 drugs as part of induction therapy, and and adults, especially younger adults, were often using many of those same components.

One of the drugs is called vincristine. It's given as a ten minute infusion, and common side effects include peripheral neuropathy that can manifest as a numbness or tingling in the fingers or toes, as well as constipation.

Another component is asparaginase. Asparaginase is a unique drug that actually deprives the malignant cells of a key amino acid. Amino acids are like the building blocks of proteins, and the leukemia cells in ALL are unable to make their own asparagine. And so we can actually deplete the ability of those cells to make their own disparaging. This has a range of unique side effects, including on the liver, as well as increasing the risk of bleeding or clotting. And so oncologists need to be prepared to monitor patients carefully during that administration.

Corticosteroids, such as prednisone or dexamethasone are also a really important type of chemotherapy that we use in treatment of ALL. Some of you may think about prednisone or dexamethasone as anti-inflammatory treatments, like what we use for asthma and for rheumatoid arthritis and things like that. But actually they are like chemotherapy to the cancer cells in patients with ALL. So we do consider that as a key component of therapy.

Now steroids do have a number of side effects as well, including on the blood sugar, on bone health, on mood and irritability, among other effects on metabolism.

And finally, we often include a fourth drug, which is what's called an anthracycline, including doxorubicin or daunorubicin. Those drugs can have effects on the heart. And so we generally will check and echocardiogram before someone starts treatment. And we monitor the cumulative dose that someone has received to make sure that we're not putting them at any increased risk.

This medication can also lower the blood counts. And so we monitor patients during induction therapy for a low platelets, low hemoglobin, low neutrophil counts for example.

Now there are other chemotherapies that do play a role during other blocks of treatment, including cyclophosphamide, cytarabine, mercaptopurine. And a number of different other agents.

Broadly, these medications suppress the normal bone marrow function in addition to having an effect on the leukemia cells. And so broadly, we're monitoring for blood count suppression during the intensive blocks of treatment that included all of these agents.

It's important to talk with your oncologist or hematologist about what the different components of a treatment block might be. So you know what to expect.