More and more women who are otherwise healthy but who are at high risk for developing breast or ovarian cancer are choosing to have a prophylactic double mastectomy or oophorectomy as a precaution against cancer.

According to a recent article in the journal Cancer Epidemiology Biomarkers & Prevention, those women who have tested positive for one of 2 breast-cancer genes identified so far (BRCA 1 or BRCA 2) have been especially willing to use this strategy to reduce their risk.

Does such a drastic step eliminate the possibility of ever getting breast or ovarian cancer? Well, it dramatically whittles the risk down to less than 5 percent, but it can never take that risk down to zero. The surgical removal of every single breast cell is physically impossible, so even a radical mastectomy is going to leave behind a few rogue cells that could potentially cause trouble later. The same caveat applies to ovarian tissue.

But for genetically positive women, who have a 65 percent to 80 percent chance of getting breast cancer and a 40 percent risk of ovarian cancer if they don't have the surgery, reducing their risk clear down to a couple of percentage points is extremely liberating for their psyches.

This type of prophylactic surgery appeals most to women who

• are between ages 35 and 45
• are identified as having a breast-cancer gene (BRCA 1 or BRCA 2)
• tested positive for a breast-cancer gene only within the last 2 years

Now, a new group of less-appropriate candidates

Lately, however, a growing number of women who only have a family history of breast cancer have been expressing interest in this--for them--rather drastic tactic. These are women, after all, who either have up til now never been tested for the known breast cancer genes at all, or who have even tested negative for one gene.

So please: Find out exactly what your real risk is before taking the surgical plunge! Don't make a sudden decision simply because you have a positive family history; meet with a genetic counselor first and get the facts.