Lump on husband's left breast area

My husband and I were showering together and told me to touch his left "breast" area. I did and there was a lump. He asked that's normal. I said I don't think so. He goes oh and continues the shower. I told him may be we should go to the doctor and make sure it's no cancerous. He says its most likely nothing and he's a man so he doubt he has cancer there.... Should we go to the hospital or am I just being overdramatic.