I had a lymph node biopsy in the clavicle (collarbone) area. The results were benign. When I told the Dr. this was good news and said it showed bright red as cancer cells on the PET scan, he said "it only showed as benign in the area where the needle went in, but the rest of the node could be malignant. I have Stage IV NSC lung cancer, and some of the other lymph nodes are showing up red on the PET Scan. I thought if a lymph node was biopsied and they said it was benign, all of it wasn't malignant. Does anyone know about this? Also, if I have a surgical biopsy of an under- thearm lymph node, do they take it all out if it's cancerous? It shows up red on PET also, but it's not swollen on the CT scan. Lymph nodes are confusing me. Please tell me of your experiences or any info you have about LN's.