Most didn't quit on purpose. Of the 127 women who had not worked since they were diagnosed, more than half said it was important for them to work, and 39 were actively looking for a job, the researchers wrote.
It happened to Kris Snow of Ann Arbor, Michigan. She was diagnosed with Stage III breast cancer in 2008, and her doctors recommended chemotherapy before she had surgery, to help shrink her tumor and make it easier to remove.
"You send an army in to weaken it and beat the crap out of it and then surgically take it out. So I said OK," Snow told NBC News
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At first, it wasn't so bad.
"Other than being extremely fatigued I didn't get that nauseous," Snow said. "When they started taxol, immediately I got numbness and tingling in (my) fingers and toes and hands," she added.
Snow, a former scientist, had reinvented herself as a home remodeler but couldn't set up contracts because of the side-effects.
"I couldn't work. I was weak and tired," she said. "The tiles and boards I picked up were heavy ... I couldn't even do painting because I was too tired." And clients were demanding the work be done immediately.
Now Snow, who is 53 and who has a 14-year-old son, is on disability. "Basically, I lost my business," she says.