Avastin may be helpful in earlier-stage breast cancers [Updated]

Use of Avastin for treating breast cancer that has spread was revoked by the Food and Drug Administration in November due to evidence that the drug did not extend survival. Two studies published Wednesday suggest Avastin may be helpful in some women with earlier-stage breast cancers. But many more questions remain about the drug’s ultimate value in treating breast cancer.

The two studies, reported in the New England Journal of Medicine, will rekindle the debate over the use of Avastin for breast cancer but are not by themselves convincing.

Both studies tested Avastin, also known as bevacizumab, with other forms of chemotherapy in women with breast cancer that had not spread beyond the site of the original tumor. The studies were designed to look for evidence that all tumor cells were gone from the breast or the breast and nearby lymph nodes. This is referred to as a “pathological complete response.”

The first study showed the rate of pathological complete response in women taking Avastin plus chemotherapy prior to surgery was 6.3 percentage points higher than among women not taking Avastin.

In the other study the rate was 3.5 percentage points higher with Avastin than without it.

Complicating matters, second trial showed a more favorable response to Avastin among women with a type of breast cancer called triple negative. But in the first trial the best response was in women with hormone-receptor-positive breast cancer.

After the FDA revoked its approval for Avastin to treat metastatic breast cancer, some researchers cautioned that the drug may still benefit a sub-group of patients, such as those with triple-negative cancers. But with the mixed results found in the studies published Wednesday -- and the lack of data on whether the drug actually affects survival in early stages of the disease -- it’s not likely patients will pin their hopes on Avastin.

[For the record, 4:40.m. Jan. 25: An earlier version of this post said that the rate of pathological complete response among women taking Avastin plus chemotherapy was 6.3% higher than among women not taking Avastin while, in the second study, the rate was 3.5% percent higher. The sentences should have said 6.3 percentage points higher and 3.5 percentage points higher.]

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