【医】 髓样癌

Encephaloid \En*ceph"a*loid\, a. [Gr. 'egke`falos + -oid.]
Resembling the material of the brain; cerebriform.

{Encephaloid cancer} (Med.), a very malignant form of cancer
of brainlike consistency. See under {Cancer}.


Cancer \Can"cer\, n. [L. cancer, cancri, crab, ulcer, a sign of
the zodiac; akin to Gr. karki`nos, Skr. karka[.t]a crab, and
prob. Skr. karkara hard, the crab being named from its hard
shell. Cf. {Canner}, {Chancre}.]
1. (Zo["o]l.) A genus of decapod Crustacea, including some of
the most common shore crabs of Europe and North America,
as the rock crab, Jonah crab, etc. See {Crab}.

2. (Astron.)
(a) The fourth of the twelve signs of the zodiac. The
first point is the northern limit of the sun's course
in summer; hence, the sign of the summer solstice. See
{Tropic}.
(b) A northern constellation between Gemini and Leo.

3. (Med.) Formerly, any malignant growth, esp. one attended
with great pain and ulceration, with cachexia and
progressive emaciation. It was so called, perhaps, from
the great veins which surround it, compared by the
ancients to the claws of a crab. The term is now
restricted to such a growth made up of aggregations of
epithelial cells, either without support or embedded in
the meshes of a trabecular framework.

Note: Four kinds of cancers are recognized: (1) {Epithelial
cancer, or Epithelioma}, in which there is no
trabecular framework. See {Epithelioma}. (2) {Scirrhous
cancer, or Hard cancer}, in which the framework
predominates, and the tumor is of hard consistence and
slow growth. (3) {Encephaloid cancer}, {Medullary
cancer}, or {Soft cancer}, in which the cellular
element predominates, and the tumor is soft, grows
rapidy, and often ulcerates. (4) {Colloid cancer}, in
which the cancerous structure becomes gelatinous. The
last three varieties are also called {carcinoma}.

{Cancer cells}, cells once believed to be peculiar to
cancers, but now know to be epithelial cells differing in
no respect from those found elsewhere in the body, and
distinguished only by peculiarity of location and
grouping.

{Cancer root} (Bot.), the name of several low plants, mostly
parasitic on roots, as the beech drops, the squawroot,
etc.

{Tropic of Cancer}. See {Tropic}.