A mosquito bite forever altered Judith Trudel's career as a surgeon.

"Within hours, my arm had swollen to three times its normal size," the Woodbury physician recalled. "It was hot and it hurt. I'd heard about lymphedema, but now it was real."

Trudel has a vague memory of her doctor warning about the risk of the condition when she was diagnosed with breast cancer at age 51.

"I was so full of fear. Lymphedema wasn't on my worry list," she said. "I was thinking about my two boys and my husband, not my arm."

That changed after the bug bite incident a year after her mastectomy.

Any insignificant injury — a cuticle nick during a manicure, a cut while chopping onions, even a sunburn — can trigger lymphedema. Any break in the skin introduces bacteria, and the lymph fluid feeds on that bacteria, causing infection. After even one bout with lymphedema, the swelling never goes completely away, which raises the risk of additional flare-ups.

Doctors and physical therapists frequently measure the arms of breast cancer survivors to track swelling. (As little as a 5 percent increase in arm size can indicate the start of lymphedema.) The lymph fluid buildup can make a survivor's arm feel hot and heavy and the swelling can extend into the hand and even the fingertips. In the worst cases, she can lose function in the limb, leaving her unable to manage fine motor skills, such as writing or even buttoning clothes.

"I had to stop doing abdominal surgery," said Trudel, now 57. "In these surgeries, there's no way to avoid little cuts on your hands. I can't think about my own risks when I'm with a patient, they have to come first."

She's shifted her professional duties to spend more time teaching medical students at the University of Minnesota and she performs rectal rather than colon surgery because it doesn't carry the same risk to her hands.

She also has made another big change: She started exercising.

"I'm a science nerd," she said. "My idea of exercise was changing the page of a book."

But when she surveyed the research that shows being physically active reduces the risk of recurrence, Trudel committed to fitness. She works out regularly and has become an enthusiastic member of the Dragon Divas paddling team.

"I had to grieve that I was not immortal," she said. "With cancer and the side effects, there's a loss. But it's also liberating. It changes your priorities and you see that life is truly a gift."

Kevyn Burger