In common with many other countries, Japan's relatively low incidence of rare types of cancer has served to dampen industry R&D and clinical trials, given the challenges in recruiting patients to studies, the limited availability of relevant medical expertise, and the comparatively small commercial opportunity for any approved products.
Put together however, rare malignancies – totaling around 200 types in total – account for fully 15% of all cancer diagnoses in Japan, and an ongoing industry-academic collaboration led by the National Cancer Center (NCC) Hospital is