When I looked up information about it, the papers were calling it "cáncer de mama", which I took to mean "mother's cancer". I thought that was a little misleading since men and non-mothers get breast cancer, too. When Nick came home from work, I told him about it, and we laughed over its seemingly ridiculous name.
The next day, he went to work and was talking it over with a co-worker and told Nick that, "No, it's not cáncer de mamá (mother's cancer), it's cáncer de mama (breast cancer)!"
Mamá, mama, papá, papa... who knows how long I've been calling mothers "breasts" and fathers "potatoes". I'm super lazy about accents in writing and in speaking, but I think I'll start being more diligent in the future. And if I've ever called you a mama, I'm sorry. :)