I need to make two important points here. First, neutrophils are a type of white blood cell tasked with fighting bacterial infections. So a low ANC can be dangerous – bacteria that normally reside in places where you would expect it can quickly become infectious without neutrophils. During front line chemotherapy, Nico’s ANC was frequently zero (literally). If you blast someone with an ANC of zero with chemo, you may very likely kill that person. So between chemo blasts, our oncologist would give Nico’s ANC time to recover by putting us on a “chemo hold.” These holds ranged from 2-3 weeks usually, and they were virtually the only times during front line that Nico’s ANC was over 500. As soon as Nico was 750, we “safely” blasted him back to 0. Now you understand why we were not very social during that first year. Second, Nico’s cancer was not in his neutrophils. His cancer was in his lymphocytes, a different white blood cell. The ANC is used as a guide to measure overall suppression, but it does not indicate whether the specific cell-type that we are targeting is being hit.
I communicate with a lot of other parents with kids in treatment (thanks Internet), and how willing oncologists are to let a kid’s ANC wander above the 1500 varies a lot. Our doctor is very conservative about this issue. He reminds Jeff and me that tight suppression, under 1500, is proven to have better long term outcomes. At first, I just kept this in the back of my mind because Nico was really low, too low even, through much of treatment. But the last two months, Nico’s ANC has been high. Our oncologist increased Nico’s dose of 6MP in September, but last month Nico’s ANC still had not budged. He is actually close to normal range at 2,900, and this is obviously not what we want. The odd thing about his counts is his ANC is the only component that is not suppressed. Looking at all his other numbers, Nico looks like his marrow is right smack in the desired range. The only number that is too high is also the only number used to determine dosage! Our doctor explained this by reminding me that our bodies are biological systems, and for whatever reason, Nico’s neutrophils can take a licking and keep on ticking. He also said that it can take several weeks for counts to reflect a recent dose adjustment.
So we are waiting to see Nico’s numbers next month before changing anything. I hope his ANC comes down. Jeff and I do not want to increase the chemo dose along with all the nasty side effects. His doctor has also ordered a lab test to take a closer at how Nico is metabolizing 6MP.
We hope everyone had a wonderful Thanksgiving. It has been over a month since I posted last, so I will include a photolog of Nico’s adventures over the last several weeks.