One in two childhood cancers go undiagnosed and untreated, study finds

Almost half of childhood cancers around the world go undiagnosed and untreated, a new study estimates. 

Even in the US, where cancer detection and treatment is advanced and effective, nearly 1,800 children die of the disease in a year. 

And children in lower income countries fare far worse. 

Due to poor monitoring programs, these cases of the disease often go not only undiagnosed and untreated but uncounted, too. 

Driven by overlooked cases and population growth in low- and middle-income countries, the Harvard University study authors estimate that some three million cases of childhood cancers will be overlooked between 2013 and 2030. 

Some 200,000 cases of childhood cancer have been diagnosed worldwide (top), but a new study estimates that the actual incidence is about double that (bottom), driven by poor and low-income countries – especially in East and West Africa (red)  

Despite the tremendous progress in fighting cancer made worldwide, it remains the leading disease cause of pediatric death from disease, even in the US. 

We are well aware of risk factors for adult cancers. Lifestyle factors like smoking, most notably can alter DNA and cause cells to divide out of control. 

But for children, cancer is largely genetic, and we don’t know why some genes seem to spontaneously go haywire. 

The types of cancer children under 20 vary regionally as well, and are particularly poorly understood in some 60 percent of countries where cancer registries don’t even exist, the new study found. 

And often, those that do have registries struggle desperately to keep complete, consistent records. 

This, in turn, means that genetic and environmental indicators of cancer risks among children aren’t tracked or identified by local doctors, who may not be trained or experienced enough to recognize them any way, and clouding our understanding of pediatric cancer in general.  

For example, study author Zach Ward, a decision scientist at Harvard University, says that leukemia – the most common childhood cancer in the US – is often said to be ‘basically non-existent in poorer countries, but that’s not true.’ 

He says that incidences are lower, but that this gross overstatement is a product of poor monitoring and under-diagnosis, rather than the absence of the cancer. 

In countries in East and West Africa, diseases like Burkitt’s lymphoma – an aggressive cancer of the immune cells – is much more common than it is in the US, or than leukemia is in Africa. 

‘A lot of it is due to genetic variability – something in that population that exposes people to certain types of cancers,’ says Ward. 

Plus, research suggests that some viruses may trigger particular cancers, too. 

But in many countries, parents may not know the signs that their child is really sick. 

Those children might not have primary care doctors and, if they do, those doctors may not recognize the signs because the cancers in their region are poorly understood. 

And that lack of understanding of childhood cancers is due, in part, to the lack of tracking of childhood cancers internationally.  

‘There was no valid estimate [for its incidence] because many countries don’t have childhood cancer registries, and even in those that do, it’s often missed because children don’t have access to primary care, so they don’t get diagnosed, much less entered into the registry,’ Ward says. 

‘There’s a long cascade of events that all have to go correctly for you to end up with a proper diagnosis and end up in a registry.’ 

Ward and his team – which is working on a larger project on the return on investment in childhood cancer care – estimated the likelihood that children would have access to a primary care provider by looking at vaccination rates and care given to pregnant women.   

In countries where the odds were low that a child saw a primary care provider to begin with, they were even  less likely to get referred to a proper specialist and diagnosed with a cancer (and that’s if their families recognized something was wrong to begin with). 

Prior estimates suggested that there were maybe some 200,000 cases of childhood cancers. The Harvard team’s study suggested far, far more go overlooked. 

‘Based on the upstream factors, there’s likely about 400,000 underlying [cases of childhood cancer] underlying what we pick up’ in registries, Ward said. 

‘We need to invest more in registries so we can focus more on uncovering this hidden burden.’ 

Spending money and time planning on developing registries may seem like a tough sell, but Ward argues its part of a larger plan to incentivize poor and middle-income countries to invest in childhood cancer overall. 

‘You need to aim a message at health and finance ministers,’ Ward says. 

‘When you look at investments for children, they are typically a good return on investment. 

‘If you save the life of a five-year-old, they have their whole working life ahead of them to be productive for your country.’ 

Callous though it might sound, its the kind of message Ward and public health experts hope can motivate struggling countries to care about overlooked childhood diseases. 

And they’ll need the most enticing arguments they can come up with, considering that Ward preliminarily estimates that introducing a registry and getting countries in gear to handles childhood cancers would cost about seven times the gross domestic product (GDP) of a country. 

Many countries, however, are taking the first, crucial steps. 

‘A lot of countries have already committed to expanding universal health coverage, and as they expand primary care, hopefully they can pick up cancer, too,’ Ward says. 

In line with the World Health Organization’s global initiative to this end, ‘the target date is 2030, but it’s an open question ad to how fast health systems can actually be strengthened to a significant degree,’ he adds. 

Ward remains optimistic, pointing at the UK and European countries – where the rate of undiagnosed childhood cancers is only three percent, according to his study – as examples. 

‘We’ve seen cancer surival in the US and Europe go from basically zero percent a few decades to the 80s now,’ he says. 

‘That shows that real progress can be made if countries make the investment.’