NEW YORK (Reuters) -- Colorectal cancer patients who carry a particular cellular protein are more likely to survive than those cancer patients who lack the protein, a new study suggests.
More than 94% of those who have the protein, called DCC (for Deleted in Colorectal Cancer), are alive five years later, compared to just 62% of colorectal cancer patients that don't carry the protein. In patients diagnosed with the most advanced cancer, 59% of those who carry DCC survive for 5 years compared to 33% who do not.
Overall, those without DCC are more than 3 times as likely to die of their cancer as those who carry the protein, according to a report in this week's issue of The New England Journal of Medicine
The finding may lead to a test for more aggressive and deadly cancer, and those with DCC-free cancer may be candidates for more intense radiation or chemotherapy, according to lead study author Dr. David Shibata, of the Harvard Medical School in Boston.
The data "support the idea that DCC is tumor suppressor gene," according to Shibata. The function of DCC is unknown, but it may play a role in limiting growth once a cell comes into contact with other tissue. Cancer cells often lose this cell-to-cell contact sensitivity, allowing tumors to overtake and crowd out normal tissue.
But one of the limitations of the study is that "detection of a protein by an antibody does not establish function," Shibata wrote. In the new study, Shibata and colleagues used antibodies that recognize DCC to analyze 132 tissue samples from colorectal cancer patients. About 50% carried the gene, which is located on chromosome 18, according to the report.
SOURCE: The New England Journal of Medicine (1996;335:1727-1732)
