Classification Of Tumors Flashcards
abnormal mass of tissue, the growth of which
exceeds and is uncoordinated with that of the normal tissues
and persists in the same excessive manner after cessation of the
stimuli which induced the change is ?
neoplasm
Tumors are classified according to behavior into?
Benign tumors
– Malignant tumors
clue for differentiation?
Morphology
All tumors have two basic components?
1) The parenchyma, made up of transformed or neoplastic
cells. (2) The supporting non-neoplastic stroma, made up of
connective tissue, blood vessels, and host-derived
inflammatory cells.
Nomenclature?
Benign tumors: In general, benign tumors are designated by attaching the suffix -oma to the cell type from which the tumor arises.
Malignant tumors
• Malignant neoplasms of epithelial cells are called carcinomas
• Malignant neoplasms arising in “solid” mesenchymal tissues,
or its derivatives are called sarcomas
benign tumor arising in fibrous tissue is ?
fibroma
benign cartilaginous tumor is
chondroma
sarcomas,
-Exceptions
sarcomas, eg. Chondrosarcoma
-Exceptions
malformation that presents as a mass of
disorganized tissue indigenous to the particular site?
Hamartoma
mass of mature but disorganized hepatic cells,
blood vessels, and possibly bile ducts within the liver?
Hamartoma
may be a hamartomatous nodule in the lung
containing islands of cartilage, bronchi, and blood vessels ?
Hamartoma
Features to distinguish between benign and malignant neoplasm:
?
- Differentiation and anaplasia 2. Rate of growth 3. Local invasion 4. Metastasis
extent to which they
resemble their normal counterparts morphologically and
functionally. ?
1.Differentiation
1.Differentiation is seen in ?
parenchymal cells
Benign neoplasms 1.Differentiation?
well differentiated
Malignant neoplasms 1.Differentiation?
range of parenchymal cell
differentiation, from well differentiated to completely
undifferentiated (anaplastic) Between the two extremes lie tumors
referred to as moderately differentiated.
Anaplastic features?
Pleomorphism (variation in size and shape of cells & their
nuclei) 2. Hyperchromatic large nuclei 3. Increased nuclear to cytoplasmic ratio (1 : 1 , normal 1 : 4 ) 4. Multi nucleated Giant cells. 5. Mitoses often are numerous and distinctly atypical; tripolar or
quadripolar mitotic figures ) 6. Fail to develop recognizable patterns of orientation to one
another (i.e., they lose normal polarity).
2.Rate of growth:
• Most benign tumor? most malignant?
grow slowly, / grow
much faster.
Poorly differentiated tumors tend to ?
grow more rapidly
than do well differentiated tumors.
grow more rapidly
than do well differentiated tumors.
?
benign
It
does not have the capacity to infiltrate, invade, or metastasize to
distant sites.
?
benign
progressive infiltration,
invasion, destruction, and penetration of the surrounding
tissue.
?
Malignant
Means the development of secondary implants (metastases)
discontinuous with the primary tumor , ?
.Metastasis
Not all cancers can metastasize ?
- Basal cell carcinomas of the skin
- Most primary tumors of the central nervous system, which are
highly invasive locally but rarely metastasize. - Carcinoids
- Giant cell tumor of bone
30% of patients with newly diagnosed solid tumors present
with?
clinically evident metastases.
Malignant neoplasms disseminate by one of three pathways?
Hematogenuos spread: 2.lympatic 3. Seeding within body cavities :
Hematogenuos spread: ?
Through the blood and it is favored by sarcomas
2.lympatic spread?
through the lymph and it is typical of
carcinomas
the first regional lymph node that
receives lymph flow from a primary tumor ?
sentinel lymph node”
sentinel lymph node” It can be identified by?
injection of blue dyes or radiolabeled tracers
near the primary tumor.
frequently involved secondary sites in
hematogenous dissemination. ?
Liver and lungs
Seeding within body cavities :
Examples ?
Characteristic of cancers of the ovary, which often cover the
peritoneal surfaces widely. • Neoplasms of the central nervous system, penetrate the
cerebral ventricles and be carried by the cerebrospinal fluid to
reimplant on the meningeal surfaces.
Gross Features Benign tumors
?
Well defined tumor margins • Cut section is uniform with no
hemorrhage or necrosis • Usually, small. • Tumor arising in solid organs are
ovoid, capsulated from
compressed surrounding
structures.
Gross Features Malignant Tumors
Tumor margins are ill
defined • Size variable. • Cut section shows
hemorrhage and necrosis. • Not encapsulated usually. • Tumor arising from surface
is either cauliflower ,
ulcerative, or infiltrative.
have the
same structural pattern
as normal tissue.
?
Benign
Cells of benign tumors are similar to
the cell of origin. The only clue to
being neoplastic is mass formation.
Benign
adipocytes
separated by CT) ?
Benign Lipoma
Thyroid adenoma
follicles
Benign
Cells of benign tumors are similar to
the cell of origin. The only clue to
being neoplastic is mass formation. Eg?
leiomyoma (fibroid) is
similar to smooth muscle of the
uterus.
MALIGNANCY FEATURES ?
• NUCLEAR SIZE (INCREASED N/C RATIO) • NUCLEAR SHAPE (PLEOMORHISM) • CHROMATIN COLOR (HYPERCHROMASIA) • CHROMATIN CLUMPS • M ITOTIC FIGURES • NUCLEOLI (M ACRONUCLEOLI OR PROMINENT
NUCLEOLI
It is hard to tell the origin of tumor cells, carcinoma, sarcoma, lymphoma or melanoma. We use?
Immunohistochemistry
Plays a role in malignant tumors for identification of tumor
type, small biopsy or undifferentiated tumors. ?
Immunohistochemistry
Immunohistochemistry of epithelial tumors ?
Cytokeratin
Immunohistochemistry of mesenchymal tumors ?
Vimentin
Immunohistochemistry of lymphoma?
Leukocytic Common Antigen (LCA
Immunohistochemistry of melanoma?
Melan A,
For tumor therapy,
targeted and hormonal
– Breast carcinoma which Immunohistochemistry is used ?
ER • PR • HER2 • KI67 • OTHERS
Slower rate of growth • Local invasion without
distant metastasis. ?
Locally Malignant Tumors
loss in the uniformity of the individual cells
and a loss in their architectural orientation.
Dysplasia
Dysplasia occurs in ?
• It occurs mainly in the epithelia meneschymal
It is a non-neoplastic process but a premalignant
condition.
Dysplasia
Dysplasia properties?
is showing a degree of pleomorphism, incearse N:C
ratio, hyperchromatism, increase mitosis, loss of polarity
and disordered maturation or total failure of maturation
• Dysplasia does not mean cancer. • Dysplasia does not necessary progress to
cancer. • Dysplasia may be reversible.
BUT
Lack of invasiveness • Reversibility
.
The differences between dysplasia and cancer: ?
Lack of invasiveness • Reversibility
The risk for invasive cancer varies with: ?
Grade of dysplasia ( mild, moderate,
sever) • Duration of dysplasia • Site of dysplasia
an intraepithelial malignancy in which malignant cells involve the entire thickness of the epithelium without penetration of the basement membrane. ?
Carcinoma In-situ