The American Cancer Society estimates that during 2001, about 12,900 cases of invasive cervical cancer will be diagnosed in the United States. Some researchers estimate that noninvasive cervical cancer (carcinoma in situ) is about 4 times more common than invasive cervical cancer.
About 4,400 women will die from cervical cancer in the United States during 2001. Cervical cancer was once one of the most common causes of cancer death for American women. Between 1955 and 1992, the number of cervical cancer deaths in the United States declined by 74%. The main reason for this change is the increased use of the Pap test, a screening procedure that permits diagnosis of pre-invasive and early invasive cancer. The death rate continues to decline at a rate of about 2% a year. The 5-year relative survival rate for the earliest stage of invasive cervical cancer is 91%. The overall (all stages combined) 5-year survival rate for cervical cancer is about 70%. For cervical precancer the 5-year survival rate is nearly 100%.
The 5-year survival rate refers to the percent of patients who live at least 5 years after their cancer is diagnosed. Many of these patients live much longer than 5 years after diagnosis, and 5-year rates are used to produce a standard way of discussing prognosis. Five-year relative survival rates exclude from the calculations patients dying of other diseases, and are considered to be a more accurate way to describe the prognosis for patients with a particular type and stage of cancer. Of course, 5-year survival rates are based on patients diagnosed and initially treated more than 5 years ago. Improvements in treatment often result in a more favorable outlook for recently diagnosed patients.
欢迎光临 英语听力论坛 (http://bbs.tingroom.com/) | Powered by Discuz! 7.2 |