Links to pictures of Sleeping Sickness (Hardin MD/ University of Iowa)
Hale Carpenter G (1920). A Naturalist on Lake Victoria, with an Account of Sleeping Sickness and the Tse-tse Fly. Unwin. OCLC 2649363.
This indicates whether chemotherapy or radiation therapy may be needed in addition to surgery. Teratomas commonly are classified using the Gonzalez-Crussi grading system: 0 or mature (benign); 1 or immature, probably benign; 2 or immature, possibly malignant (cancerous); and 3 or frankly malignant. If frankly malignant, the tumor is a cancer for which additional cancer staging applies.Teratomas are also classified by their content; a solid teratoma contains only tissues (perhaps including more complex structures); a cystic teratoma contains only pockets of fluid or semifluid such as cerebrospinal fluid, sebum, or fat; a mixed teratoma contains both solid and cystic parts. Cystic teratomas usually are grade 0 and, conversely, grade 0 teratomas usually are cystic. Grades 0, 1, and 2 pure teratomas have the potential to become malignant (grade 3), and malignant pure teratomas have the potential to metastasize. These rare forms of teratoma with malignant transformation may contain elements of somatic (not germ cell) malignancy such as leukemia, carcinoma, or sarcoma. A teratoma may contain elements of other germ cell tumors, in which case it is not a pure teratoma, but rather is a mixed germ cell tumor and is malignant. In infants and young children, these elements usually are endodermal sinus tumor, followed by choriocarcinoma. Finally, a teratoma can be pure and not malignant yet highly aggressive;  this is exemplified by growing teratoma syndrome, in which chemotherapy eliminates the malignant elements of a mixed tumor, leaving pure teratoma, which paradoxically begins to grow very rapidly.