Al's Comment:

This is a fascinating idea, particularly for brain tumors. Researchers looked at newborn blood samples from 1,948 children who later developed a solid tumor or brain tumor by age 8 and found that about 7% carried a detectable mutation in one of 11 cancer-predisposition genes. For some brain tumors the numbers were much higher: mutations were found in about 30% of children who developed choroid plexus carcinoma, 17% with pineoblastoma and 11% with medulloblastoma.

 

Knowing about these mutations at birth could allow doctors to monitor high-risk children closely and hopefully find a tumor when it is very small, potentially improving survival and allowing less-toxic treatment.

 

But there is an important downside that needs to be considered. These cancers are extremely rare. The researchers estimate that only about 1 out of every 27,000 newborns would go on to develop a cancer by age 8 that could have been predicted by this 11-gene screening panel.

 

That does not necessarily mean 26,999 children would undergo MRIs and other intensive screening to help one child. The initial genetic test would be performed on the blood spot already routinely collected from newborns, and only children found to carry a significant mutation would be referred for additional surveillance. Importantly, these mutations appear to be quite rare in healthy newborns.

 

Still, for a child who tests positive, surveillance can become a significant burden. Depending on the particular gene, it can involve repeated physician visits, blood tests, ultrasounds, eye examinations and imaging such as MRI—sometimes beginning in infancy and continuing for years. There is also the possibility of anxiety for the family, overdiagnosis and procedures prompted by findings that ultimately prove harmless. The study authors themselves acknowledge these concerns.

 

So I think the concept is promising, especially for syndromes where the risk of developing cancer is very high and we already know that early detection makes a difference. But before adding cancer genes to routine newborn screening, we need to know something this study cannot yet tell us: How many children need years of additional surveillance to prevent one cancer death or serious disability?

 

Finding a genetic risk is only valuable if acting on that information does more good than harm.

Screening newborns for cancer risk