L8: Introduction to Neoplasia

Question 1

What is the term “neoplasia”?

Answer 1

The term “Neoplasia”:-
Neo = new
plasia = creation (growth)

Question 2

What is the term “Tumor”?

Answer 2

tumor = swelling

Question 3

What is the definition of neoplasia?

Answer 3

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.

Question 4

What is any tumor composed of?

Answer 4

Cells:

• *Which is neoplastic
• *May be benign or malignant
• *Tumor is named according to it.

Supporting stroma: which is non-neoplastic

Question 5

What are tumors classified according to?

Answer 5

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

Question 6

What are tumors of epithelial origin?

Answer 6

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

Question 7

What is papilloma?

Answer 7

Papilloma = benign tumor of surface epithelium.

Question 8

What is adenoma?

Answer 8

Adenoma = benign tumor of secretory epithelium.

Question 9

What is carcinoma?

Answer 9

Carcinoma = malignant tumor of epithelium.

Question 10

What are tumors of mesenchymal origin?

Answer 10

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

Question 11

What is fibroma?

Answer 11

benign tumor of fibrous tissue.

Question 12

What is fibrosarcoma?

Answer 12

malignant tumor of fibrous tissue.

Question 13

What Is liposarcoma?

Answer 13

malignant tumor of fat cells.

Question 14

Compare between benign and malignant tumors

Answer 14

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

Question 15

What is the origin of benign tumors?

Answer 15

Arise from normal cells.

Question 16

What is the origin of malignant tumors?

Answer 16

1- Arise from either normal cells or premalignant lesions.

Question 17

How do begin tumors grow?

Answer 17

Grow slowly by expansion (i.e. push the surrounding normal tissue without tissue damage).

Question 18

How do malignant tumors grow?

Answer 18

Grow rapidly by both expansion & infiltration (i.e. infiltrate & damage the surrounding normal tissue).

Question 19

What is the N/E of benign tumors?

Answer 19

• single.
• small.
• capsulated.
• no hemorrhage or necrosis.

Question 20

What is the N/E of Malignant tumors?

Answer 20

• begin single then spread.
• reach a large size in a short time.
• non-capsulated
• hemorrhage or necrosis

Question 21

What is the M/E of the benign

tumors?

Answer 21

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.

Question 22

What is the M/E of malignant tumors?

Answer 22

• *cells: show criteria of malignancy.
• *Pattern of arrangement: depends on tumor grade.

**stroma:
prominent bl. Vs.,
with hemorrhage & necrosis.

Question 23

What is the prognosis of benign tumors?

Answer 23

5- Prognosis:-

• *No spread
• *No recurrence
• *Not harmful except if:
• In vital organ
• Obstruct hollow organ
• Produce hormone
• Turn malignant

Question 24

What is the prognosis of malignant tumors?

Answer 24

• 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

Question 25

What are the Microscopic Criteria of malignancy (not present in benign tumors)?

Answer 25

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.

Question 26

What is a Tumor grade?

Answer 26

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).

Question 27

What are the grades for any tumor?

Answer 27

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)

Question 28

What is the definition of locally malignant tumors?

Answer 28

``` 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. ```

Question 29

What are the examples of Locally malignant tumors?

Answer 29

``` 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. ```

Question 30

What does the tumor grade estimate?

Answer 30

It estimates the tumor aggressiveness.

Question 31

What is the tumor stage?

Answer 31

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).