Is Small Cell Carcinoma In The Crease Of The Arm A Concern?

My husband had an area inside the bend of his arm. we went to his dermatologist and she took a sample to send to the lab. less than a week later she called and wanted to see him back in her office where she took more tissue. She called today to refer him to an Oncologist. He has had Basil Cell Carcinoma on his chin before and she really had to take a large amount of his chin tissue to get it all. Now this is Small Cell Carcinoma and there is nothing else she can do and refered him to an Oncologist. Everything I m seeing about this is referring to Small Cell Lung Cancer. What is the Oncologist going to do and how serious is this?