Behavior of Neoplasms

Question 1

Define neoplasia.

Answer 1

CLONAL amplification of a single cell resulting from heritable genetic changes

Question 2

Define neoplasm. (5)

Answer 2

Abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the changes (becomes autonomous)

• -Typically arises from a single cell
• -Stepwise genetic alterations permit excessive growth
• -A disease of cell signaling

Question 3

Define benign.

Answer 3

A localized neoplasm which does not kill the host.

Question 4

Define malignant.

Answer 4

A neoplasm which invades, spreads to distant sites, and kills the host

Question 5

(OBJ) List eight histological features associated with malignant neoplasms.

Answer 5

Pleomorphism - variation in size and shape
High nuclear to cytoplasmic ratio
Hyperchromasia - increased density of nuclear chromatin
Nuclear contour irregularities
Clumped chromatin, condensed along nuclear membrane
Abnormal mitoses (e.g. tripolar)
Loss of polarity
Necrosis

Question 6

Define differentiation.

Answer 6

The degree to which a neoplasm resembles the normal tissue counterpart

Question 7

Define metastasis.

Answer 7

Cells detach from primary tumor mass, spread to a distant site, and resume proliferation in the new site
May occur through lymphatics, blood vessels, or within a body cavity

Question 8

**Define tumor grade.

Answer 8

The degree of differentiation of a malignant neoplasm (well -> moderately -> poorly -> anaplastic), along with the number of mitoses and amount of necrosis
–The extent to which neoplastic cells mimic their terminally differentiated normal counterpart, both morphologically and functionally

Question 9

**Define tumor stage.

Answer 9

Classification of the EXTENT of involvement by a malignant neoplasm
–Uses TNM method

Question 10

**How do tumor stage and degree affect prognosis?

Answer 10

Stage (extent of involvement) is more predictive of patient outcome than is grade (degree of differentiation)

Question 11

**(OBJ) Explain and apply the TNM method of cancer staging.

Answer 11

Tumor-specific staging classification based on…

• -Size of the primary Tumor
• -Involvement of lymph Nodes
• -Location/extent of Metastases (beyond the lymph nodes)

Question 12

(OBJ) Name the three most common neoplasms in men in the US.

Answer 12

Prostate (25%)
Lung (15%)
Colorectal (10%)

Question 13

(OBJ) Name the three most common neoplasms in women in the US.

Answer 13

Breast (26%)
Lung (14%)
Colorectal (10%)

Question 14

(OBJ) Explain the rationale behind a biopsy of the “sentinel lymph node.”

Answer 14

Pattern of lymph node involvement follows the natural route of lymphatic drainage
Use biopsy of sentinel noes to assess presence of absence of metastatic lesions in lymph nodes
–Sentinel node: the first node in a regional lymphatic basin that receives lymph flow from the primary tumor
–Performed using tracers and dyes as guides

Question 15

Define autonomous.

Answer 15

responding, reacting, or developing independently of the whole <a></a>

Question 16

Describe the process of clonal progression. (3 steps)

Answer 16

1. One cell picks up a mutation that gives it a growth advantage over the rest of the population, allowing it to proliferate
2. One or two cells, of the first clonal expansion, picks up a second mutation that gives it another advantage over the rest of the population, allowing them to proliferate
3. Process repeats as neoplasm becomes more and more aggressive

Question 17

T/F: Many years pass (often >20) from the time a particular cell gets its first mutation that sets it on the path to dysplastic growth to the time it becomes cancerous.

Answer 17

TRUE!