ABCs Cancer

Question 1

Benign Tumors

• (Do/do not) invade tissue?
• (Do/do not metastasize?
• _____ cytologic changes

Answer 1

• Do not
• Do not
• Minimal

Question 2

What is a neoplasm?

Answer 2

A new growth

Question 3

Malignant Tumor

• ____ cytologic changes
• (Do/do not) invade surrounding tissue
• (Do/do not) metastasize

Answer 3

• Observable
• Do
• Do

Question 4

What is the leading cancer in women?

What is the leading cancer in men?

Answer 4

Breast

Prostate

Question 5

Hyperchromatic

Answer 5

Nuclei appear darker than normal

Question 6

Pleiomorphic cells in cancer cytology

Answer 6

Cells of the same type appear different from one another

Question 7

In class, we discussed adenocarcinoma of the colon that was due to a mutation in the KRas gene. Recall that Ras is a monomeric G protein. What effect did this single mutation have that led to cancer?

Answer 7

The Ras pathway was turned on even in absence of ligand (EGF). Ras signaling results in activation of MAPK pathway, which is a strong proliferative signaling pathway.

Question 8

What techniques are required to diagnose cancer?

Answer 8

Tissue sampling

Immunohistochemistry

Flow cytometry

Molecular/cytogenic analyses

Question 9

Biopsies

• Core needle
• Incisional
• Excisional

Answer 9

• Cannulated needle inserted to remove piece of tissue that is a cylindrical core
• Incisional - take larger section of tissue
• Excisional - take whole mass

Question 10

Define cancer.

Answer 10

Disease caused by abnormal and uncontrolled cell proliferation that is followed by invasion and colonization of body sites that are normally reserved for other cells

Question 11

Describe how a single cell becomes a cancerous mass.

Answer 11

A single cell acquires a carcinogen induced mutation. The cell then acquires another mutation that affects genomic integrity. The cell then acquires additional mutations that drive the cell toward becoming cancerous. The founding cancer cell continues to acquire mutations and begins to divide, resulting in a population of cancerous cells that are heterogenous and all acquiring new mutations independently of one another. This could ultimatley lead to tissue invasion and metastases.

Question 12

How does cancer achieve unchecked growth?

Answer 12

Upregulate growth promoting genes

Repress tumor suppressor genes

Repress genes that regulate apoptosis

Repress genes involved in DNA repair

Question 13

What is the warburg effect?

Answer 13

The principle that cancer cells metabolize glucose to lactate so little pyruvate actually enters the krebs cycle. As such, they ahve increased GLUT receptors and a different isoform of pyruvate kinase.

Question 14

How do cancers become vascular?

Answer 14

They induce angiogenesis for their own growth purposes

Question 15

How is the grade of cancer determined?

Answer 15

By looking at cytologic characterizations:

• Degree of differentiation
• Number of mitosis

Question 16

How is the stage of cancer determined?

Answer 16

• Size of primary lesion and extend of invasion/metastases
• TNM (tumor size, lymph node status, metastases

Question 17

Describe the general process of metastasis.

Answer 17

The primary tumor produces proteases that are able to degrade the basement membrane of the tissue where the tumor is located. The cancer cells then migrate into the ECM and degrade the ECM. Cells enter vascular system and interact with platelets to form a tumor cell embolus which protects the tumor cells somewhat. At distant site, cancer cells extravasate from vascular system and migrate through ECM in new tissue to new site where the induce angiogenesis and grow.