Is mastitis found only in women?

"yes" Most common post -partum but other times infection or inflammation can occur but always this has to be checked by a md for the rare possibility of inflammatory breast cancer males they luck out again -- rare- I have only 2 in 3! years with cysts and infection -one due to trauma-- one with 2nd dcis.
No. Mastitis is an infection of breast tissue. All men and women have breast tissue. Obviously women have a larger amount. However, it is exceedingly rare to see mastitis in a male.