Lymph node cancer. Light micrograph of a section through lymph node with a malignant (cancerous) tumour. This tumour is a carcinoma and is metastatic, meaning that it is derived from epithelial cells and is spreading rapidly throughout the body. Metastatic carcinomas found in the lymph nodes are usually secondary cancers that have originated elsewhere in the body. They appear different from the lymphocytes (white blood cells) that normally fill lymph nodes, in that they have large nuclei, are disorganised, and are poorly differentiated. Spread via the lymphatic system is common and often greatly reduces the chance of survival. MNF-116 antibody stain. Magnification: x570 when printed 10 centimetres wide.