The National Cancer Center (NCC) released three-year survival rates for 11 types of cancer for the first time on Sept. 11, rather than waiting to accrue data for the usual five-year rates.
The three-year survival rate for patients diagnosed in 2011 with one of the 11 types of cancer stood at 71.3 percent overall. The rate was 99 percent for men with prostate cancer, 95.2 percent for women with breast cancer. In contrast, the figure was just 15.1 percent for sufferers of difficult-to-cure pancreatic cancer.
In the past, the NCC announced five-year figures based on diagnoses made roughly 10 years earlier, but decided to analyze and release data on patients who received more recent treatments without waiting for the accumulation of data for the five-year rates.
The center came up with the figures by analyzing the data of 306,381 patients at 268 medical facilities, including leading cancer-treatment hospitals. Relative survival rate calculations were made for different stages of 11 types of cancer, including five major types of cancer common in Japan -- stomach, colon, liver, lung and breast cancer. The rates excluded deaths due to causes unrelated to cancer, such as other diseases or accidents.
Among patients with the five major types of cancer, those having liver or lung cancer had a lower chance of survival, and the figures for stomach cancer also plummeted in more advanced stages. Breast cancer had a higher survival rate, and this is considered to be due to the relatively young age of patients, according to the NCC.
Five-year survival rates are considered the standard for judging if a patient is cured. But Fumihiko Wakao, who heads the NCC's Center for Cancer Control and Information Services, explained that the center decided to release the three-year data to provide timely information that included the effect of new treatments.
"When the five-year data for the same patients become available, it may become easier to make faster judgments on the effectiveness of certain treatments," explained Wakao. The data is available online at https://ganjoho.jp in Japanese.