Nearly one in two children with cancer are never diagnosed and may die untreated, according to a a new model proposed in a study published in The Lancet Oncology by Zachary Ward and colleagues from Harvard University T.H. Chan School of Public Health.
In fact, the model estimates that there were 397.000 childhood cancer cases globally in 2015, while only 224,000 had been previously recorded as diagnosed that year, leading ultimately the researchers to say that over 43% of childhood cancer cases were undiagnosed. But there was substantial regional variation: it ranges from 3% in both Western Europe (120 undiagnosed cases out of 4,300 total new cases) and North America (300 of 10,900 cases), to 57% (43,000 of 76,000 new cases) in Western Africa. With such path, at current levels of health system performances, If no improvements are made, the study authors estimated that nearly three million out of 6.7 million total cases will be missed between 2015 and 2030.
Accounting for underestimation is vital: accurate estimates of incidence are important for policy makers, however, many countries do not have cancer registries that quantify that incidence (and often even if they do have, cases might be incorrectly classified). “As the hidden incidence of childhood cancer starts to come to the fore, stronger health systems are needed for timely diagnosis, referral and treatment,” says Ward. “Expanding cancer registration will be important so that progress can be tracked.”
Although in most regions of the world the number of new childhood cancer cases is declining or stable, authors estimate that more than 90% of all new cases occur in low and middle-income countries. “Health systems in low-income and middle-income countries are clearly failing to meet the needs of children with cancer. Universal health coverage, a target of United Nations Sustainable Development Goals, must include cancer in children as a priority to prevent needless deaths,” says senior author Professor Rifat Atun, Harvard University, USA.
The study was funded by Boston Children’s Hospital, the Dana-Farber Cancer Institute, the Harvard T.H. Chan School of Public Health, Harvard Medical School, the National Cancer Institute, SickKids, St Jude Children’s Research Hospital and the Union for International Cancer Control.