It is allow for international doctors to apply for breast surgical oncology I am a general surgeon with board certificate and mrcsi thanks?

See SSO website. Go to http://www.Surgonc.Org/training--education/breast-oncology-fellowships/program-requirements.Aspx.
May be. International doctors(international medical graduates) can rarely get into speciality training without first doing general training in the us. So you may have to repat some of your surgery training first. Then it is eaier to become a surgical oncologist. But the best way to find this is to write to or meet with a surgical oncologist in a major cancer center and seek further guidance.