Colorectal cancers that have spread to other parts of the bodycan be hunted down and perhaps even destroyed with a newtracing technique.

British researchers at Hammersmith Hospital in London,reporting Saturday in the journal Lancet, are taking thepatient's immune cells and activating them outside the body byexposing them to cells removed from the patient's primarycancer. The scientists then label the activated killerlymphocytes with a radioactive tracer, inject them and trackthem to the sites of cancer metastasis.

Lung and liver metastases, identified by conventional meansbefore the tracer test, were tracked successfully by the killercells in six patients. The researchers are now testing thetumor-activated killer cells as therapy in 10 additionalpatients.

The technique bypasses use of interleukin-2, which can betoxic, the researchers said in their report. Adoptiveimmunotherapy using interleukin-2 has had initial success atthe National Cancer Institute against melanoma and has wonapproval as an initial candidate for gene therapy.

Cetus and Immunex are attempting to develop interleukin-2 foruse in cancer.

-- Roberta Friedman, Ph.D. Special to BioWorld

(c) 1997 American Health Consultants. All rights reserved.