HMGA2 has been proposed as a marker to identify malignant tumors.

Studies in mouse models have shown that Cy5.5 can identify tumors with as few as 2000 cancer cells, making it 500 times more sensitive than MRI.

Wild and his team were able to take ultrasound scans of breast tissue that could be used as a noninvasive means to identify and diagnose tumors.

Another important role of the immune system is to identify and eliminate tumors.

For many years, breast X-rays were largely used as a diagnostic tool to help identify possible tumors discovered in physical exams.

Flow cytometry analysis identifies low-stage, low-grade tumors at high risk of recurrence by virtue of their aneuploid histograms.

The doctor can identify tumors by looking at the sonogram.

Isotopes are often preferentially absorbed by biologically active tissue in the body, and can be used to identify tumors or fracture points in bone.

"Molecular signatures will allow us to identify tumors that are insensitive to a particular form of treatment from the get-go," Dr. Cordon-Cardo said.

So, he said, if genetic signatures can identify tumors that are dangerous, though small, "that could be a major advance."