The actress, who played Tom Cruise's love interest in Mission: Impossible III, was forced by her husband to visit a doctor for a check-up during a vacation in Australia - and she's glad she went.
She tells the November (11) issue of Health magazine, "In Australia, they're very aware of skin cancer. I finally went and it was skin cancer. I had quite the chunk taken out of my leg."
And now Monaghan is very cancer-aware: "I smoked for almost 10 years. I really regret that. Thankfully, I came out on the other side. I hope my lungs are repairing themselves now."