L8: Introduction to Neoplasia Flashcards
What is the term “neoplasia”?
The term “Neoplasia”:-
Neo = new
plasia = creation (growth)
What is the term “Tumor”?
tumor = swelling
What is the definition of neoplasia?
An abnormal mass of tissue which:
1- Grows more rapidly than the normal tissue.
2- Its growth is uncontrolled by the normal growth control mechanisms (autonomous).
3- Competes with the normal tissue for metabolic needs.
What is any tumor composed of?
Cells:
- *Which is neoplastic
- *May be benign or malignant
- *Tumor is named according to it.
Supporting stroma: which is non-neoplastic
What are tumors classified according to?
Tumors can be classified according to:
The cell of origin into:
1- of epithelial origin
2- of mesenchymal origin
Behavior into:
1-benign
2-malignant
3-locally malignant
What are tumors of epithelial origin?
Benign tumors
Papilloma:
From surface epithelium e.g. squamous cell papilloma
And transitional cell papilloma
Adenoma:
From secretory epithelium e.g. tubular adenoma and liver cell adenoma
Malignant tumors
The name of epithelium + carcinoma e.g. squamous cell carcinoma and transitional cell carcinoma and hepatocellular carcinoma
What is papilloma?
Papilloma = benign tumor of surface epithelium.
What is adenoma?
Adenoma = benign tumor of secretory epithelium.
What is carcinoma?
Carcinoma = malignant tumor of epithelium.
What are tumors of mesenchymal origin?
Benign tumors
-The name of mesenchymal tissue + oma
- from fibrous tissue — fibroma
- from cartilage ——— chondroma
- from bone ————- osteoma
- from fat —————- lipoma
Malignant tumors
-The name of mesenchymal tissue + sarcoma
- from fibrous tissue — fibrosarcoma
- from cartilage ——– chondrosarcoma
- from bone ————- osteosarcoma
- from fat —————- liposarcoma
What is fibroma?
benign tumor of fibrous tissue.
What is fibrosarcoma?
malignant tumor of fibrous tissue.
What Is liposarcoma?
malignant tumor of fat cells.
Compare between benign and malignant tumors
Origin Growth N/E M/E Prognosis
1- Arise from normal cells.
1- Arise from either normal cells or premalignant lesions.
2- Grow slowly by expansion (i.e. push the surrounding normal tissue without tissue damage).
2- Grow rapidly by both expansion & infiltration (i.e. infiltrate & damage the surrounding normal tissue).
3- N/E:- *single.
- small.
- capsulated.
- no hemorrhage or necrosis.
3- N/E:-
- begin single then spread.
- reach a large size in a short time.
- non-capsulated
- hemorrhage or necrosis
4- M/E:-
**cells: similar to cell of origin, no criteria of malignancy.
**Pattern of arrangement: similar to tissue of origin.
**stroma:
few blood vessels,
no hemorrhage or necrosis.
4- M/E:- **cells: show criteria of malignancy. **Pattern of arrangement: depends on tumor grade. **stroma: prominent bl. Vs., with hemorrhage & necrosis.
5- Prognosis:- **No spread
- *No recurrence
- *Not harmful except if: *In vital organ
- Obstruct hollow organ *Produce hormone *Turn malignant
5- Prognosis:-
- spread occurs either:
- direct (in surrounding tissue)
- distant metastasis [by blood, lymphatic vessels or through serous sacs (transcoelomic)]
- recurrence occurs (due to infiltrating borders with the absence of capsule)
- harmful due to:
- Organ destruction (infiltration) *Obstruction of hollow organ *Clinical syndromes related to tumor
What is the origin of benign tumors?
Arise from normal cells.
What is the origin of malignant tumors?
1- Arise from either normal cells or premalignant lesions.
How do begin tumors grow?
Grow slowly by expansion (i.e. push the surrounding normal tissue without tissue damage).
How do malignant tumors grow?
Grow rapidly by both expansion & infiltration (i.e. infiltrate & damage the surrounding normal tissue).
What is the N/E of benign tumors?
- single.
- small.
- capsulated.
- no hemorrhage or necrosis.
What is the N/E of Malignant tumors?
- begin single then spread.
- reach a large size in a short time.
- non-capsulated
- hemorrhage or necrosis
What is the M/E of the benign
tumors?
cells: similar to cell of origin, no criteria of malignancy.
* *Pattern of arrangement: similar to tissue of origin.
**stroma:
few blood vessels,
no hemorrhage or necrosis.
What is the M/E of malignant tumors?
- *cells: show criteria of malignancy.
- *Pattern of arrangement: depends on tumor grade.
**stroma:
prominent bl. Vs.,
with hemorrhage & necrosis.
What is the prognosis of benign tumors?
5- Prognosis:-
- *No spread
- *No recurrence
- *Not harmful except if:
- In vital organ
- Obstruct hollow organ
- Produce hormone
- Turn malignant
What is the prognosis of malignant tumors?
- spread occurs either:
- direct (in surrounding tissue)
- distant metastasis[by blood, lymphatic vessels or through serous sacs(transcoelomic)]
- recurrence occurs (due to infiltrating borders with the absence of capsule)
- harmful due to:
- Organ destruction (infiltration)
- Obstruction of a hollow organ
- Clinical syndromes related to tumor
What are the Microscopic Criteria of malignancy (not present in benign tumors)?
1- Pleomorphism (variability in size & shape of cells & nuclei).
2- Hyperchromatism (dense chromatin inside the nuclei).
3- increased N/C ratio to 1:2 (instead of 1:4 in normal cells).
4- Tumor giant cells.
5- Atypical (abnormal) mitoses.
6- Prominent nucleoli.
What is a Tumor grade?
It means the degree of similarity of tumor tissue to the tissue of origin regarding morphology & function (i.e. how much the tumor resembles the normal tissue).
What are the grades for any tumor?
1- Grade I (well-differentiated tumors).
2- Grade II (moderately differentiated tumors).
3- Grade III (poorly differentiated tumors).
4- Grade IV (undifferentiated tumors = anaplastic tumors)
What is the definition of locally malignant tumors?
These are tumors characterized by: 1- Grow by local infiltration. 2- No blood or lymphatic spread. 3- Microscopically show criteria of malignancy. 4- Recur after incomplete removal 5- May turn malignant.
What are the examples of Locally malignant tumors?
1- Adamantinoma of mandible. 2- Basal cell carcinoma of the skin. 3- Craniopharyngioma of the pituitary gland. 4- Carcinoid tumor. 5- Giant cell tumor of bone.
What does the tumor grade estimate?
It estimates the tumor aggressiveness.
What is the tumor stage?
It is based on 3 items: [TNM staging system]
1- the size of the primary tumor.
2- presence or absence of lymph node spread.
3- presence or absence of metastasis (distant spread).
