NCI: An abnormal mass of tissue that usually does not contain cysts or liquid areas. Solid tumors may be benign (not cancer), or malignant (cancer). Different types of solid tumors are named for the type of cells that form them. Examples of solid tumors are sarcomas, carcinomas, and lymphomas. Leukemias (cancers of the blood) generally do not form solid tumors.,NCI: A benign or malignant neoplasm arising from tissues that do not include fluid areas. Representative examples include epithelial neoplasms (e.g. lung carcinoma, prostate carcinoma, breast carcinoma, colon carcinoma), and neoplasms arising from the soft tissues and bones (e.g. leiomyosarcoma, liposarcoma, chondrosarcoma, osteosarcoma). Neoplasms originating from the blood or bone marrow (leukemias and myeloproliferative disorders) are not considered solid tumors.