In the United States, the average life span of cancer patients, that is the life span from being diagnosed with cancer to death is 7 years, while the average life span of cancer patients in Asia is only 4 years. 
On the whole, the United States' awareness of self-care is higher than that of Asians, so the early diagnosis rate of cancer patients in the United States is higher than that in Asia
 the United States has a higher level of medical care in extending the lifespan of cancer patients than Asia.