IT BEGAN AS ONE OF THOSE TYPICAL DINNERTIME CONVERSATIONS. After my husband and I had settled in at an outdoor café, I mentioned that a co-worker’s sister, only 35 years old, had been diagnosed with breast cancer. “Wow, that’s young,” he said, munching on a french fry. It was. And lately it seemed that more people my age—50—or younger were staring down cancer. Whenever I heard about a new case among my acquaintances, I’d murmur sympathetic words. My mother withered away from breast cancer, and I’d experienced the confusion, grief and utter lack of sleep that come with caring for someone terminally ill.

But much as I want to run from those memories, I can’t. Because my mother succumbed to breast cancer, my chance of developing the disease is increased. My five-year risk, according to the National Cancer Institute, is 2.5%, vs. the 1.3% average for women my age.

I’ve been careful through the years to undergo every screening test my doctor recommends. On top of a yearly mammogram, I’ve had an MRI. Genetic testing to determine if I am a carrier of a mutated BRCA1 or BRCA2 gene, which quintuples breast cancer risk, was an option I’d considered over the years but batted away. Whereas a mammogram or an MRI might reveal something definite—a suspicious mass, a lump requiring further inspection—a positive result from a genetic test would merely suggest something bad might happen.

My husband was against the test too. “Do you really want to know?” he asked when I first brought it up. “What would you do with the information?”

I knew from trolling the Internet that if I had BRCA1 or BRCA2, there were steps I could take to shield myself from the disease. I could, for example, take tamoxifen, which can suppress the growth of breast cancer cells. But my mom had taken it after her first bout with cancer, and it left her so lethargic and unable to think clearly that she could not hold down a job.

A prophylactic mastectomy was another possibility. This scared my husband even more. “Why cut out a perfectly healthy part of your body?” he said. “It’d be like cutting off your leg just because you might get gangrene. Or like cutting off your finger because you might get bone cancer.”

“Don’t be ridiculous,” I spat. “You need your legs to walk. And you need your fingers. I could function fine without breasts.” I could chalk up my husband’s reaction to typical male thinking—what, a woman cut off her breasts? But I sensed at least partly what he felt.

As I mulled over the decision, I kept returning to a conversation I’d had with my friend Louis. His mother had died instantly of a heart attack at age 83 after a remarkably active life. “How much would you pay to guarantee you could go that quick?” Louis had asked me. “Ten thousand dollars? A hundred thousand?”

Far from a guarantee, a genetic test would lead only to more uncertainty, and I’m not the type of person who dwells on what can go wrong. Moreover, neither a positive nor a negative test result is definitive. So what, in the end, is the test’s usefulness? If I were at even greater risk—if, say, my sister had also developed breast cancer—I’d consider it. But for now, a positive result would be like a sword hanging over my head. I’d rather pretend it isn’t there.

To know or not to know—which is the wiser? Share your view.