Answer to Question 1
1918
Answer to Question 2
Positron emission tomography (PET) scans create representations of the functioning of the body and the mind. They are used to study Alzheimer's disease, Parkinson's disease, epilepsy, learning disabilities, moral reasoning, bipolar disorder, and cancer. PET scans are also used to diagnose arterial obstructions. In a recent study, PET scans were compared with more common diagnostic tests for breast cancer. The two techniques disagreed in 25 percent of the cases; PET scans provided the correct diagnosis 80 percent of the time, as compared with 12 percent using conventional imaging techniques. PET scans found 6 true positives' that were not found with conventional imaging tests. As a result those women began more aggressive treatment. Otherwise they would not have received treatment at that particular time. A study published in 2006 concluded that whole-body PET scans could help determine whether breast cancer had spread before surgery.
A recent study has found that PET scans can measure the response of a patient with esophageal cancer to chemotherapy and radiation therapy before surgery. PET scans also can detect metastases that other imaging techniques cannot see and can be used to predict survival rates.