Avastin may help slow ovarian cancer tumors

New studies suggest that the drug Avastin, when treating women with ovarian cancer, can slow tumor growth when added to chemotherapy.

But- it's not clear whether the drug may improve life expectancy.The news comes less than a week after officials in Europe approved Avastin for treating advanced ovarian cancer.

It has not yet been approved by the Food and Drug Administration to treat ovarian cancer in the U-S.

"I have no doubt that Avastin is a very powerful drug for some patients," said Dr. Gabriel Hortobagyi, chair of MD Anderson Cancer Center department of breast medical oncology, according The Los Angeles Times. "The problem with Avastin is we don TMt have a biomarker to help us identify the sub-group."

Results of the studies are in the New England Journal of Medicine.Last month, the F-D-A withdrew approval of Avastin for breast cancer because it did not extend life and can have serious side effects.

(CNN contributed to this article)