Why Neuroblastoma Screening Doesn't Work
Late last week I read a great article on *** cancer screening. Of course, I read the article because my little word search of it also included the word 'neuroblastoma.' Regardless, the article brought up some very important points that I think are often missed by parents of a child with neuroblastoma. The subject is this neuroblastoma screening.
What if we could catch neuroblastoma more quickly? What if we could keep a stage 1 from becoming a stage 2, a stage 3, or even a stage 4? What if we could catch kiddos even before the neuroblastoma was really showing at all?
It seems an easy enough solution. If we could just catch it earlier, it would be easier to defeat and it would spare children a ton of toxicities.
It is this line of thinking that lead many to raise research funds for prescreening and apply pressure to institutions to start prescreening.
The problem is that in neuroblastoma this line of thinking was misguided. The prescreening model did not work in neuroblastoma. In fact, believe it or not, prescreening for neuroblastoma caused more deaths and saved less lives.
There are many reasons for this seemingly counter intuitive finding. The first issue relates to the disease itself. Early stages of the disease are very different from the later stages of the disease. They are so different that there are many that believe that they may in fact be different diseases. In other words, if you were stage 1 you were probably always destined to be a stage 1. While the tumor may grow this form of the disease just doesn't possess the metastatic and deadly potential of the stage 4 disease. On the other side of this coin, if you had stage 4 disease you were probably, from the very beginning, always destined to have the most aggressive form of the disease. At the very beginning, it was probably already already showing the aggressive characteristics that make it so deadly. In other words, catch it early or catch it late, it is believed by many that you would always have stage IV disease. That form of the disease is that quick and that aggressive.
It is this issue, among others, that was experienced in screening for neuroblastoma. Several studies used urine tests to screen for neuroblastoma. The good news was that they caught a lot of it. There are reports that neuroblastoma incidence nearly doubled. The problem though was that they were not able to differentiate the "good" neuroblastoma from the "bad" neuroblastoma. In fact, many of these neuroblastomas went away on their very own. What we ended up discovering was that there was significantly more "good" neuroblastoma than we previously knew about.
Unfortunately, once we knew these kiddos had neuroblastoma we had to do something about it. We had no idea which kids had the good form and which kids would develop the bad form. So we treated them. There were hundreds of kids that received treatment for neuroblastoma that would have certainly gone away without any treatment what so ever. These kids were now scarred for life with side effects - unnecessarily. Worse yet, there were many that died - not from the disease but from the treatment. Yes, children died that would not have because we screened them. Had we not screened them, their tumors would have spontaneously regressed and those children would be alive today and those families would be whole.
Worse than that, the screening did nothing to increase the survival rates of children with stage IV disease. Those children still lost their battles in record numbers.
In the end, what we found was that by using screening techniques we were able to find a lot of the "good" neuroblastoma but we really did not find any more "bad" neuroblastoma. Worse, when we did get a head start on the disease treatment did not appear to have any impact on survival.
Dr. Archie Bleyer was one of the oncologists involved in the studies years ago that evaluated screening for neuroblastoma in children. I think he stated the cost of screening in neuroblastoma best.
“Once we diagnosed neuroblastoma, we had to do something about it,” Bleyer said. “And I have to say we killed some kids because of it.”
While I wish there was a tool or utility which could help us identify the "bad" neuroblastoma more quickly, their simply is no such tool available today. The good news is that there has been much research on new methods of identifying the worst cases of neuroblastoma. It will take time though before anything is capable of finding the answers we are looking for.
In the meantime, don't beat yourself up. Most likely, screening would not have helped you and it probably would have cost some other children's lives unnecessarily.