THE BIOLOGY OF TERATOMAS
L E R O Y C. S T E V E N S
The Jackson Laboratory, Bar Harbor, Maine
I. Introduction
1
II. Classification
2
III. Distribution
3
A. Species
3
B. Influence of Sex and Age
4
C. Laterality
5
IV. Composition
6
V. Nature of the Stem Cell
8
VI. Progression
9
VII. Cell of Origin
11
VIII. Extragonadal Teratomas
14
IX. Pathogenesis
14
X. Genetic and Environmental Influences on Teratocarcinogenesis
.
.
15
A. Multiple Gene Influences
15
B. Single Gene Influences
18
C. Karyotype
19
D. Environmental Influences
19
XI. Sex of Teratomas
21
XII. Embryoid Bodies
23
X I I I . Experimental Induction of Teratomas
25
A. In Fowl
25
B. In Adult Mammals
25
C. In Mammalian Fetuses
26
XIV. Plant Teratomas
26
XV. Summary
27
References
28
I. Introduction
Teratomas have always intrigued biologists and pathologists. They
are congenital malformations, but they are also neoplastic. They may be
benign or highly malignant. Their composition may be relatively simple
or they may have almost as many kinds of tissues as the individual bearing
them. In certain circumstances they can produce structures, embryoid
bodies, which resemble embryonal stages of the host species. The teratocarcinogenetic process resembles carcinogenesis, in that it results in
1