Limitations
There are some limitations to our study. First, the medical expenses calculated in our study only indicate those covered by health insurance. We were unable to obtain non-covered medical expenses; however, most costs related to childhood cancers are covered by national health insurance. Secondly, we did not include the medical expenses associated with subsequent non-cancer-related doctor visits and treatments. However, as cancer treatments comprise very intensive care, we expect that other treatment costs would not substantially alter our results. Thirdly, we only considered whether the patients received treatments such as surgery, chemotherapy, and radiation, but not the frequency at which they received them. Therefore, further studies are necessary to overcome these limitations.