A solid tumour is an abnormal mass of tissue that usually does not contain cysts or liquid areas. Solid tumours may be benign (not cancer), or malignant (cancer). Solid tumour types are named according to the type of cell they originate from. Examples of solid tumours include sarcomas, carcinomas, and lymphomas. Leukaemias (cancers of the blood) generally do not form solid tumours.
The word tumor does not always imply cancer. In discussing tumors that are malignant (cancerous), however, the term solid tumor is used to distinguish between a localized mass of tissue and leukemia.
Metastatic epithelial-derived solid tumours is an umbrella term that that includes tumour types such as gastric cancer, pancreatic cancer, breast cancer, ovarian cancer and many others.