Protein Predicts Lung Cancer's Response to Treatment

(HealthDay News) -- Levels of a protein linked to cellular DNA repair can predict how well non-small-cell lung cancer patients will respond to cisplatin, a common chemotherapy.

So concludes a French study published in the Sept. 7 New England Journal of Medicine.
Patients with low levels of the protein marker, called ERCC1, "will have a very significant level of benefit from adjuvant cisplatin-based chemotherapy," said lead researcher Dr. Jean-Charles Soria, from the Department of Medicine, Institute Gustave Roussy, Villejuif.

Cisplatin is a standard component of chemotherapy for lung and other cancers; however, not everyone benefits from the drug. This new study suggests that screening for levels of the ERCC1 protein in lung biopsies can help doctors determine who will benefit from the treatment and who will not.

According to the American Cancer Society, lung cancer accounts for 13 percent of all new cancers and is the leading cancer killer of American men and women. Non-small cell cancers comprise 85 percent of the nearly 175,000 new cases of lung cancer diagnosed in the United States each year.
In their study, Soria's group looked at 761 lung cancer tumors. Of these, 44 percent had high levels of ERCC1, and 56 percent had low levels of the protein.

They found that patients who had low levels of ERCC1 benefited from cisplatin treatment, which helped extend life for these patients.

However, this was not the case among patients with high levels of ERCC1.
These patients "do not derive benefit from adjuvant chemotherapy, and if not treated, they do have a better 'spontaneous' prognosis than those who are ERCC1-negative," Soria said.

The French researcher believes that ERCC1 screening could spot those most likely to benefit from cisplatin treatment. "In our study, ERCC1 expression was evaluated by means of immunohistochemistry" of tissues in the laboratory, he said. "This is a simple technique, reliable, cheap and widely applicable," he added.

Screening patients might also help determine individual reaction to treatment, he added. "The goal of providing individualized chemotherapy based on different genetic traits, such as polymorphisms, gene mutations, and overexpression of drug target proteins, is on the verge of becoming clinical practice for the benefit of cancer patients," Soria said.

Two other experts agreed that ERCC1 screening should become part of a standard assessment of how patients might react to platinum-based chemotherapy, such as cisplatin.

"In my view, it's time to begin to think about whether or not we should begin to use this information to screen patients," said Dr. Eddie Reed, the director of the Division of Cancer Prevention and Control at the U.S. Centers for Disease Control and Prevention, and the author of an accompanying journal editorial.

Reed believes that ERCC1 screening for other cancer where cisplatin is commonly used -- such as ovarian and colorectal cancer -- needs to be examined, as well. "It's time to consider whether or not we should use this strategy," he said.

Dr. Norman Edelman, chief medical officer for the American Lung Association, agreed.
ERCC1 screening "is something that could save a substantial number of patients a substantial amount of discomfort," he said.

More information
Find out more about lung cancer at the American Cancer Society.