Overview
- Analysis covers about 2.547 million cases diagnosed in 2012–15 across 44 prefectures, with five-year survival for stomach at 63.5%, colorectal at 67.2%, and lung at 35.5%.
- Pancreatic cancer remains especially lethal at roughly 10.5% five-year survival, with gallbladder and bile-duct cancers also showing little improvement.
- Compared with 1993–96, many cancers gained 15.5–34.9 percentage points in survival, but bladder and cervical cancers declined for reasons officials say remain unclear.
- Stage at diagnosis proved decisive, with organ-confined disease showing very high survival (for example, stomach 92.4% and female breast 98.4%) versus poor outcomes after distant metastasis.
- Marked regional disparities emerged, including lower stomach survival in Aichi, Okinawa, Ibaraki, Gunma, and Saitama and lower lung survival in Aomori, Fukushima, Okinawa, and Hokkaido, while variation was relatively small for female breast and uterine cancers.