Genetic test developed for gastrointestinal cancers

In collaboration with the Press Association

A simple genetic test could be used to distinguish between two near-identical gastrointestinal cancers that nonetheless require very different treatments, say researchers.

The test appears to be able to distinguish gastrointestinal stromal tumour (GIST) from leiomyosarcoma (LMS) with a near 100 per cent accuracy.

The two cancers originate in the same smooth muscle tissue of the gastrointestinal tract. GIST was once thought to be a form of LMS.

GIST responds well to the drug imatinib (Glivec) and poorly to the chemotherapy used to treat LMS. Imatinib is ineffective against LMS.

The test correctly identified the different tumour types in 67 out of 68 samples, while a second trial correctly identified 20 samples with 100 per cent accuracy.

"This simple and accurate test has the potential to be relatively quickly implemented in the clinic to benefit patients by guiding appropriate treatment," said senior author Wei Zhang, Professor in the department of pathology at the University of Texas MD Anderson Cancer Center.

Current methods only have an accuracy of 87 per cent, but intensive and time-consuming additional analyses are required for uncertain cases.

The study is published in the Proceedings of the National Academy of Science.