Miércoles 5 de Junio de 2002, Ip nº 16

Study: Surgery can prevent breast, ovarian cancer
ORLANDO, Florida (Reuters) -- Women who inherit genes that put them at high risk of breast and ovarian cancer can prevent both by having their ovaries removed, doctors said on Monday.

They said their study gave a new option to women with faulty BRCA1 and BRCA2 genes, whose lifetime risk of cancer is much higher than the average woman's.

"The risk for breast and ovarian cancer decreased 75 percent in the surgery group," Dr. Kenneth Offit of the Memorial Sloan-Kettering Cancer Center in New York, who led the study, told a news conference.

BRCA mutations account for between 4 and 10 percent of all cases of breast and ovarian cancer, or about half of all cases of inherited breast cancer.

Women with BRCA mutations have a lifetime risk of breast cancer of anywhere between about 60 and 85 percent, and a lifetime risk of ovarian cancer of between 15 and 65 percent.

Until recently, there was not much they could do about it. The anti-cancer drug tamoxifen has been shown to reduce the risk of cancer by close to 50 percent in high-risk women who take it for five years, but research shows that does not work for women with BRCA1 mutations.

Some of those women have opted for a mastectomy, which reduces their risk of cancer but is a radical solution. Others choose to get regular mammograms and breast checks.

The options for reducing the risk of ovarian cancer are to have the ovaries removed, which brings on menopause in women who have not already gone through it, or to have regular blood tests and ultrasounds.

Offit's team followed 173 women with BRCA mutations, 101 of whom had their ovaries and fallopian tubes removed.

Three of those women were found to have tiny tumors already in their ovaries, Offit told the annual meeting of the American Society for Clinical Oncology in Orlando.

After two years, three of the women who had their ovaries removed developed breast cancer and one developed ovarian cancer in the surrounding tissue -- which is called peritoneal cancer.

Among the 72 women who kept their ovaries, there were eight cases of breast cancer, four cases of ovarian cancer and one case of peritoneal cancer.

Breast cancer cut in half

"The incidence of breast cancer was dramatically reduced, essentially cut in half by removing the ovaries," ASCO President Dr. Larry Norton told reporters.

He said the ovaries may continue to produce estrogen that stimulates the growth of cancer. Both breast and ovarian cancer are often related to estrogen's action on cells.

"This is clearly a big impetus to removing the ovaries in women who are predisposed to cancer because of BRCA1 and BRCA2 problems," Norton said.

"We now have prospective evidence to present to patients so that they can make informed decisions about their care," Offit said in a statement.

ASCO Executive Vice President Dr. Charles Balch said it should put many women's minds at ease, especially women past menopause who fear they will develop cancer because of a family history.

"Women are driven by extreme anxiety. Women who have had mothers, sisters, die in their arms, say, 'I don't want to go through that,"' Balch said.

The researchers said most women affected by BRCA risk were already past childbearing years, so they did not need to worry they would have to give up on having a family to reduce their cancer risk.

"The median age for this procedure was 45, well after childbearing years," Offit said.

  20/05/2002. CNN.