Exam 3 (Lecture 17) - Neoplasia 1

Question 1

What is oncology?

Answer 1

The clinical field of studying neoplasms.

Question 2

What is a neoplasm?

Answer 2

“New growth”

An ABNORMAL MASS of tissue, the growth of which is uncoordinated with that of the normal tissues and persists in an excessive manner after the cessation of the stimuli which evoked the change.

Question 3

What is a tumor?

Answer 3

“A swelling”

Question 4

What is a benign neoplasia?

Answer 4

1) A neoplasm that’s unlikely to cause harm
2) DOES NOT invade surrounding tissue
3) DOES NOT spread to other anatomic locations

Question 5

What are the key features of neoplasia?

Answer 5

1) Excessive growth (vs. hyperplasia)
2) Lack of responsiveness to normal growth controls
3) Independent of causal stimulus
4) Heritable from cell to cell (mutation)

Question 6

What is neoplastic transformation?

Answer 6

The process whereby a cell becomes neoplastic = “transformed” cell.
- Becomes autonomous
- Not subject to normal growth controls
- Free of normal structural and functional constraints (however; may outgrow its blood supply)

Question 7

What are preneoplastic changes?

Answer 7

Changes preceding tumor emergence.

Tumor development is a step-wise process; increases the likelihood for progression to neoplasia in the affected tissue.

Question 8

What is a malignant neoplasia?

Answer 8

1) A neoplasm LIKELY to cause harm
2) INVADES locally
3) SPREADS by metastasis (“change of places”)

• THE TERM CANCER ALWAYS MEANS MALIGNANT!!!!

Question 9

What does cancer mean?

Answer 9

Malignant neoplasm

Question 10

What is a carcinoma?

Answer 10

Neoplasm of epithelial origin; malignant

Question 11

What is a sarcoma?

Answer 11

Neoplasm of mesenchymal origin; malignant

Question 12

What is metastasis?

Answer 12

Distant spread of neoplasm (AKA “mets”)
- Primary site
- Secondary site = metastasis

Question 13

What are mesenchymal tumors?

Answer 13

1) Tumors that arise from cells of embryonic mesodermal origin.

2) These tumors are generally composed of spindle cells arranged in streams and bundles or round cells arranged in solid sheets.

3) Benign tumors originating from mesenchymal cells are usually named by adding the suffix -oma to the name of the cell of origin.
- Ex: Fibroma = A benign tumor of fibroblast origin

Question 14

What are hematopoietic tumors?

Answer 14

1) Round cells of the hematopoietic system (cells in bone marrow and blood vessels); also mesenchymal.

2) Tumors arising from these cells are called sarcomas.
- Ex: Lymphosarcoma = A malignant tumor of lymphocytes

3) Malignancies arising from circulating blood cells or their precursors are termed leukemias (“white blood”)

Question 15

What are epithelial tumors?

Answer 15

1) Tumors that arise from all three germ layers (endoderm, mesoderm, and ectoderm).

2) The terms adenoma, papilloma, and polyp refer to benign epithelial tumors.

3) Adenoma =Denotes either a tumor arising from glandular epithelium with characteristic acini and duct (benign).

4) ALL malignant tumors of epithelial origin are termed carcinomas (“cancers”).

Question 16

What are the tumor types?

Answer 16

1) Mass
2) Neoplastic

Question 17

What are the types of mass tumors?

Answer 17

1) Abscess
2) Granuloma
3) Hyperplasia

Question 18

What are the types of neoplastic tumors?

Answer 18

1) Round Cell
- Lymphoma
- Mast cell tumors
- Plasma cell tumors

2) Epithelial
- Adenoma
- Carcinoma

3) Mesenchymal
- “bump” -oma
- Sarcoma

Question 19

What is a hamartoma?

Answer 19

Disorganized, mature tissue in a normal anatomic location.

Question 20

What is a choristoma?

Answer 20

Normal, mature tissue at an ectopic site.
- Ex: Dermoid

Question 21

What are benign and malignant tumors of connective tissue/fibroblasts called?

Answer 21

Benign = fibroma

Malignant = fibrosarcoma

Question 22

What are benign and malignant tumors of fat/adipocytes called?

Answer 22

Benign = lipoma

Malignant = liposarcoma

Question 23

What are benign and malignant tumors of cartilage/chondrocytes called?

Answer 23

Benign = chondroma

Malignant = chondrosarcoma

Question 24

What are benign and malignant tumors of bone/osteoblasts called?

Answer 24

Benign = osteoma

Malignant = osteosarcoma

Question 25

What are benign and malignant tumors of blood vessels/vascular endothelium called?

Answer 25

Benign = hemangioma

Malignant = hemangiosarcoma

Question 26

What are benign and malignant tumors of lymphatic vessels/lymphatic endothelium called?

Answer 26

Benign = lymphangioma

Malignant = lymphangiosarcoma

Question 27

What are benign and malignant tumors of synovium/synovial lining cells called?

Answer 27

Benign = synovial myxoma

Malignant = synovial histiocytic sarcoma

Question 28

What are benign and malignant tumors of mesothelium/mesothelial cells called?

Answer 28

Benign = ?

Malignant = mesothelioma

Question 29

What are benign and malignant tumors of meninges/meningeal lining cells called?

Answer 29

Benign = meningioma

Malignant = malignant meningioma

Question 30

What are benign and malignant tumors of ovary/modified mesothelium called?

Answer 30

Benign = adenoma

Malignant = adenocarcinoma

Question 31

Describe benign tumors.

Answer 31

Often encapsulated (separated from normal tissues by fibrous connective tissue).

Generally grow in an expansile way, compressing adjacent tissue.

Question 32

Describe malignant tumors.

Answer 32

Often unencapsulated or grow through the tumor capsule.

Invading or infiltrating the surrounding tissues as they grow.

Alterations in cell adhesion, motility, and protease production allow tumor cells to leave the tumor mass and
penetrate surrounding tissue.

Must become completely independent of local growth regulatory controls and acquire an independent blood supply to invade tissues and ultimately metastasize.

Question 33

How is tumor behavior assessed?

Answer 33

Cytologic, gross, and microscopic features.

Cytology = Criteria of malignancy

Histology = Is there presence of lymphatics? Is the tumor well demarcated or invasive?

Question 34

Morphologic diagnosis for tumors:

Answer 34

Organ: Cell of origin, benign/malignant, metastatic (?)

Ex in oral cavity: Squamous cell carcinoma

Question 35

Describe the gross appearance of neoplasms in regards to color.

Answer 35

The color can resemble that of the parent tissue.

Can also be:
- Black = melanocytic origin
- Dark red = hemorrhage; highly vascular
- Pale = new growth; necrosis; calcification

Question 36

Describe the consistency of neoplasms.

Answer 36

Connective tissue = Firm
- EXCEPT myxoma/myxosarcoma

Bone = Hard

Edema = Soft

Friable = Reduced blood supply

Question 37

What is the two stage theory of carcinogenesis?

Answer 37

1) Initiators likely cause mutations of specific genes

2) Promoters often act by causing proliferation or selection of transformed clones

*Some chemicals are “complete carcinogens” (ie cause the mutations/proliferation)

Question 38

Is initiation genetic? Is it reversible?

Answer 38

Genetic; irreversible

Question 39

Is promotion genetic? Is it reversible?

Answer 39

Nongenetic; reversible

Question 40

Is progression genetic? Is it reversible?

Answer 40

Can be either; can also be either; depends on situation

Question 41

What is latency in regard to tumor growth?

Answer 41

The time before a tumor is clinically detectable.
- Smallest detectable mass is 1 cm diameter (about 109 cells)
- Once they’re clinically detectable, they only need 10 subsequent doubling cycles are required to convert
a 1g tumor into a 1kg tumor.

Question 42

What is proliferation in regard to tumor growth?

Answer 42

Failure to enter the G0 (non replicative) phase of the cell cycle.

Failure of arrest at checkpoints in the cell cycle.