Early detection is critical to the clinical outcome in the treatment of cancers. As an example, colon cancer accounts for 15% of all cancer-related deaths in the United States. Unfortunately, only 37% percent of colon cancers are found early enough for moderate treatment. Once this type of cancer reaches metastatic activity (spreads), there is only a 7% survival rate. Oral cancer is another example. Each year about 31,000 Americans develop oral cancer. Squamous-cell carcinoma (SCC) accounts for 95% of all malignant oral lesions, and it has a survival rate of only 50%. Yet when this type of cancer is detected in its earliest stages, the survival rate becomes approximately 80%. In cancers of the esophagus, the 5-year survival rate is only 5%. In contrast, if this type of cancer is detected when it is still contained in the mucosa, the 5-year survival rate becomes 90%.