Is It It Normal To Have Staph Infection After Undergoing Surgery For Cancerous Tumor?

A friend of mine had surgery on Monday the 10th of this month, It was for a cancerous tumor in her ovary. She went home on the 13th and by Friday the 14th was in much pain, By Monday morning a week after the surgery she was in so much pain she went to the ER and she was admitted to the hospital. The took tests and It came back positive for staph infection. They inserted a vacuum pump and put her on antibiotics. She was told today that she does have staph and the antibiotics are not helping, either from the radiation pills she has taken because of the cancer or she is immune to them. She will go back into surgery today to replace the sponge type thing from her stomach and they will assess her, Do you know of anything else they could do to help her? She is a great friend and I am concerned about her SO MUCH! Thank you!