LECTURE 9: Neoplasia Flashcards
occurs when a group of cells becomes free of normal growth control mechanisms, grows without regard for the normal structural and functional aspects of a tissue or an organ and excessive growth becomes
autonomous.
Neoplasia
Neoplasia literally means _______
“new growth”
Neoplasia literally means “new growth”, and this tissue growth is called a ________.
neoplasm
an abnormal mass
of tissue, the growth of which exceeds and is uncoordinated with that of normal
tissues, and persist in the same excessive manner after cessation of the stimulus that evoked the change.”
Neoplasm
Classical definition of a neoplasm points to it as
an abnormal mass
of tissue, the growth of which exceeds and is uncoordinated with that of normal
tissues
From the neoplasia definition, three features are important:
1) it is an excessive tissue growth,
2) it lacks responsiveness to control mechanisms
3) it lacks continued dependence on the stimulus that initiated it
is an abnormal mass of tissue due to an increase in the number of constituent cells
hyperplasia
is a form of pathological hyperplasia
neoplasia
difference between Hyperplasia and Neoplasia
Hyperplasia is a retrogressive change that is reversible and is responsive to growth control mechanisms
a retrogressive change that is reversible and is responsive to growth control mechanisms
HYPERPLASIA
Difference between hyperplasia and neoplasia
HYPERPLASIA
Function: - Functional purpose
Response: - Stops after removal of stimuli
Change: - Reversible
Control: - Regulated
NEOPLASIA
Function: - Non-viable purpose
Response: - Uncontrollably persistent
Change: - Irreversible
Control - Autonomous
thought to be a malady of a mysterious
cause, the external appearance of which seemed to be being eaten away by small crabs
Neoplasm
In the early days, neoplasms were thought to be a malady of a mysterious cause, the external appearance of which seemed to be being eaten away by small crabs. This observation led to the naming of the condition as _______.
cancer
cancer, after the zodiac symbol for _______.
crabs
the term has been associated with malignant neoplasms
cancer
Another term that lay people use to refer
to neoplasm is _______
tumor
Neoplasm is also called what?
Tumor
It is a tissue swelling or mass that may or may not be neoplasm.
tumor
Common usage of the word tumor, however, comes to mean what?
neoplasm
It is the study of neoplasia.
ONCOLOGY
this word is the basis of
oncogenesis and oncogenic, which relate to the induction of neoplasia
ONCOLOGY
relate to the induction of neoplasia
ONCOGENESIS and ONCOGENIC
Oncology is the basis of what?
oncogenesis and oncogenic
Information on cell growth control mechanisms was derived from ________.
cell cultures
When normal cells are grown _________, they spread out to form a single sheet of cells (cell monolayer).
in vitro
single sheet of cells
cell monolayer
Growth ceases when the cells reach a certain population density where they remain quiescent but healthy. This mechanism is called ______.
DENSITY-DEPENDENT INHIBITION or CONTACT INHIBITION OF GROWTH
Growth ceases when the cells reach a certain population density where they remain quiescent but healthy. This mechanism is called density-dependent inhibition or contact inhibition of growth, and is governed by chemical messengers, collectively known as ________.
chalones
chemical messengers, collectively known as _______
chalones
They grow in haphazard fashion, piling up into multiple layers, and tend to grow until they have exhausted the culture media, with less responsiveness to density dependent inhibition
Neoplastic cells
When normal cells, as influenced by some factors, loses their innate characteristics and become ___________
neoplastic cells
When normal cells, as influenced by some factors, loses their innate characteristics and become neoplastic cells, the process is known as _______.
NEOPLASTIC TRANSFORMATION
Morphologically, Transformed Cells exhibit the following
characteristics:
1) May or may not resemble their cell origin;
2) Presents increased nucleus to cytoplasmic ratio, the nuclei being enlarged, hyperchromatic and may be multinucleated;
3) Chromosomes may present mitotic figures;
4) They lack orientation to adjacent cells;
5) Decreased rough endoplasmic reticulum and increased free ribosomes.
Besides morphological changes, Transformed Cells exhibit the following characteristics:
1) Transplantability
2) Immortality
3) Tumorigenicity
4) Antigenic changes
5) Karyotypic changes
6) Biochemical changes
will grow in tissue culture or in a syngeneic host
Transplantability
will divide and replicate indefinitely provided that nutrients required for growth are present
Immortality
forms tumors or tissue masses in syngeneic host
Tumorigenicity
presents altered surface antigens
Antigenic changes
although the observed changes are rarely characteristic of any one tumor, chromosomal damage or alteration
in base pairs may be basic to the induction of neoplasm
Karyotypic changes
neoplastic cells contain less cyclic adenosine monophosphate (cAMP) and more cyclic guanosine monophosphate
(cGMP) than normal cells. The absence of normal enzymes or the presence of abnormal ones can occur.
Biochemical changes
neoplastic cells contain ___________ than normal cells.
less Cyclic Adenosine Monophosphate (cAMP)
and
more Cyclic Guanosine Monophosphate (cGMP)
are named according to the features of differentiation recognizable in histologic examinations reflecting their tissue origin
Neoplasms
Based on the tissue origin, the neoplasm could be what?
EPITHELIAL or MESENCHYMAL
When neoplasm with more than one neoplastic cell type are derived from one embryonic germ layer, they are called _______.
MIXED NEOPLASM
mixed neoplasm common example is the _________.
mammary gland tumors in dogs
proliferating epithelial tissue is intermixed with mesenchymal components, such as bone and cartilage
Neoplasm
It is a neoplasm containing tissue derived from more than one germ layer, and may contain any number of tissues of any type, including bone, skin, nervous tissue, muscle, hair and others
teratoma
Teratoma is a neoplasm containing tissue derived from more than one germ layer, and may contain any number of tissues of any type, including what?
bone
skin
nervous tissue
muscle
hair
teratoma is a neoplasm containing
tissue derived from more than one germ layer, and may contain any number of
tissues of any type, including what?
BONE
SKIN
NERVOUS TISSUE
MUSCLE
HAIR
Classifications of Neoplasm
- Histogenetic Classification
- Behavioral Classification
It describes those that are relatively inoffensive, grow slowly by expansion, are circumscribed, do not undergo metastasis
and presents very few mitotic or apoptotic figures, and is rarely fatal.
benign neoplasm
refers to those that are aggressive and potentially life threatening
malignant neoplasm
They present infiltrative growth patterns, sometimes expansive, grows in size rapidly, have a high number of mitotic and apoptotic figures, metastasis is usually present, and the condition terminates fatally.
malignant neoplasm
naming neoplasms
NOMENCLATURE
naming neoplasms, both are used
HISTOGENETIC CLASSIFICATION SCHEMES
BEHAVIORAL CLASSIFICATION SCHEMES
Benign neoplasms carry the suffix ________.
-oma
a benign neoplasm derived from fibroblast is called _________
FIBROMA
Benign neoplasms derived from glandular epithelia are called ________.
adenomas
a benign neoplasm derived from ________ is called fibroma.
FIBROBLAST
Benign neoplasms derived from _____________ are called “adenomas”
GLANDULAR EPITHELIA
This term refers to those with a solid lobular pattern of growth and those with
recognizable acini, ducts and tubules
ADENOMA
Because the term “adenoma” is
nonspecific, the tissue origin is usually named __________.
e.g., adenoma of sweat gland,
thyroid gland adenoma,
or adrenal cortex adenoma
neoplasms of epithelial origin if it forms cystic cavitations, it is called ____________.
CYSTADENOMA
It is one that forms branching finger-like projections into the lumen
PAPILLARY ADENOMA
is one derived from ducts
DUCTULAR ADENOMA
ductular adenoma is one derived from _____________
DUCTS
are neoplasms growing at the surfaces
POLYPS / PAPILLOMA
Malignant neoplasms of mesenchymal origin are called ________.
SARCOMA
Malignant neoplasms of __________ are called sarcoma
MESENCHYMAL ORIGIN
malignant neoplasm of fibroblastic origin is called
fibrosarcoma
Malignant neoplasm of _______ is called fibrosarcoma.
fibroblastic origin
Malignant neoplasms of _________ are called carcinoma
epithelial origin
Malignant neoplasms of epithelial origin are called
carcinoma