Is it harmful to have a dog living with you if you have breast cancer?

Be careful: If someone is receiving chemotherapy and has low blood counts, i would suggest being careful. Avoid close exposure during that time, make sure the doggie is healthy, etc. Otherwise, having a dog (preferably an inside dog) can have positive effects on patients mood. Common sense should prevail. Best to you.

Should be ok: I would limit direct contact immediately after surgery while your wounds are healing. But after your best friend can be a welcome companion and supporter.