Introduction to Neoplasia (Part I)

Question 1

What does the term “clonal” mean in terms of neoplasia?

Answer 1

All neoplastic cells are clones of one original altered cell.

Question 2

Examples of benign tumors

Answer 2

Adenoma
Papilloma
Fibroma
Cystadenofibroma

Question 3

Examples of malignant tumors

Answer 3

Carcinoma (most common adult type)
Sarcoma
Leukemia
Lymphoma

Question 4

What are carcinomas?

Answer 4

Malignant neoplasms of epithelial origin, derived from any of the 3 germ layers (ectodermally derived epidermis, mesodermally derived renal tubules, endodermally derived GI tract).

Question 5

What are sarcomas?

A few examples:

Answer 5

Malignant neoplasms that affect mesenchymal tissues (soft tissues).

Fibrosarcoma, chondrosarcoma, leiomyosarcoma, rhabdomyosarcoma.

Question 6

What is the parenchyma and stroma?

Answer 6

Parenchyma is the tissue that gives rise to the neoplastic component (the part that is benign or malignant, etc.).
Stroma is the supportive cellular component (structural part) of what the parenchyma resides in. NOT generally neoplastic. Consists of blood vessels and CT.

Question 7

What is the difference between an adenoma and a polyp?

Answer 7

An adenoma is a benign epithelial neoplasm derived from glands.
A polyp occurs when glandular tissue produces a visible projection from the mucosal surface.

Question 8

What is a mixed tumor?

Answer 8

A tumor that has several divergent differentiations of a single neoplastic clone. The cells are from the same germ layer.

Question 9

What is a teratoma?

What is an example?

Answer 9

It is a neoplasm that contains several different cell types from multiple germ cell layers.

An ovarian cystic teratoma may include skin, hair, teeth and glands.

Question 10

What is tumor differentiation?

Answer 10

The extent to which neoplastic parenchymal cells resemble the corresponding normal cells.

Question 11

What are the 2 major determinants of tumor differentiation?

Answer 11

1. The neoplastic cells’ nuclei and cytoplasm (large nuclei).
2. The architectural relationship of the neoplastic cells to the other neoplastic cells and non-neoplastic cells.

Question 12

Which tumors are well-differentiated?

Poorly-differentiated?

Answer 12

Benign tumors are well-differentiated, meaning they closely resemble the parental cells.

Malignant tumors are poorly differentiated.

Question 13

The less the differentiation, the more:

Answer 13

Likely the tumor is to be aggressive

Question 14

What is anaplasia?

Answer 14

Term used to describe the lack of differentiation, which is a hallmark of malignany.

Question 15

Grading system for neoplasms (4)

Answer 15

Well: closely resembles parental cells.

Moderately: features of parent tissue are identifiable, but is not the dominant pattern, with associated atypia.

Poorly: a small minority of parental cells; associated with anaplasia.

Undifferentiated: tissue of origin cannot be determined. Almost always associated with anaplasia.

Question 16

Which histopathologic criteria are used w/ anaplasia and what are they? (5)

Answer 16

1. Pleomorphism: changes in cell size and shape. All cells within the tumor are not the same size.
2. Abnormal nuclear morphology: nuclei are disproportionally large. They are often irregularly shaped and darkly stained.
3. Mitoses: indicate rapid cell division. Malignancies are associated w/ atypical, bizarre mitotic figures.
4. Loss of polarity: the orientation of anaplastic cells is disturbed. Large masses of cells grow in a disorganized way.
5. Ichemic necrosis due to inadequate blood supply from the stroma.

Question 17

What is dysplasia?

What do dysplastic cells show?

Answer 17

Disordered growth.

May show pleomorphism and abnormal nuclear morphology.

Question 18

What is the process of dysplastic squamous epithelium?

Answer 18

The epithelium has a normal progression from tall basal cells to flattened apical cells. This process may fail and lead to replacement of the epithelium w/ basal-appearingcells with hyperchromatic nuclei.
There also might be increased amount of mytotic figures.

Question 19

When does carcinoma in situ occur?

Answer 19

It occurs when dysplastic changes are marked and involve the full thickness of the epithelium, but the lesion does NOT penetrate the basement membrane. It is pre-invasive and may last many years before it becomes invasive.

Question 20

What 3 things accompany the growth of cancers?

Answer 20

Progressive infiltration
Invasion
Destruction of surrounding tissues

Question 21

Which tumors can invade?

Answer 21

Malignant only

Question 22

What is the morphology of a benign tumor?

Answer 22

They produce a fibrous capsule (from fibroblasts and stroma due to hypoxia). The tumor is palpable, non-fixed and easily excised.

Question 23

What is the morphology of a malignant tumor?

Answer 23

They are poorly demarcated from their surroundings and there is no defined cleavage plane.

Question 24

What are the 2 most important features that differentiate benign from malignant tumors?

Answer 24

The ability to invade and metastasize

Question 25

Which malignant cancers don’t tend to metastasize? (2)

Answer 25

Gliomas

Basal cell carcinomas

Question 26

Which 3 things is the likelihood of metastasis correlated with?

Answer 26

Lack of differentiation, aggressive local invasion and large size.

Question 27

What are the 3 major pathways for which malignancies are disseminated?

Answer 27

1. Direct seeding of body cavities or surface: occurs when a malignant neoplasm penetrates a natural open barrier. Occurs most often into the peritoneal cavity. Common of ovarian carcinomas.
2. Lymphatic spread: transport through the lymphatics, which is the most common form of dissemination of carcinomas. Tumors do not have lymphatics, so they take advantage of the host’s.
3. Hematogenous spread: most common manner of spreading for sarcomas. Cancer cells generally enter the venous system, which explains why mets to the lung and liver are common.

Question 28

What is a sentinel lymph node?

Answer 28

The LN where a BX is taken. It is the first node in a regional lymphatic area that receives lymph from the primary tumor.

Question 29

Which cancers metastasize via hematogenous spread? (3)

Answer 29

Renal cell carcinoma - invades renal v.
Hepatocellular carcinomas - penetrate portal and hepatic radicles.
Mets from the vertebral column - can travel to thyroid and prostate via the paravertebral plexus.

Question 30

Incidence vs. prevalence

Answer 30

Incidence is the amount of new cases, which prevalence is the amount of people affected total.

Question 31

What was incidence of cancer in 2008?

How many deaths yearly? Daily?

What is the incidence and mortality expected to be by 2030?

Why?

Answer 31

12. 7 mil.
13. 6 mil deaths yearly, 21,000 daily.

Incidence of 21.4 mil and mortality of 13.2 mil.

Due to increasing population and age.

Question 32

Top 4 most common cancers (by incidence) in men in 2014

Answer 32

1. Prostate
2. Lung
3. Colorectal
4. Bladder

Question 33

Top 4 most common cancers (by incidence) in women in 2014

Answer 33

1. Breast
2. Lung
3. Colorectal
4. Uterus and thyroid are tied

Question 34

Which 4 cancers are the highest in mortality rate in men in 2014

Answer 34

1. Lung
2. Prostate
3. Colorectal
4. Pancreas

Question 35

Which 4 cancers are the highest in mortality rate in women in 2014

Answer 35

1. Lung
2. Breast
3. Colorectal
4. Pancreas

Question 36

How many new mutations occur every time a cell divides?

Answer 36

3

Question 37

What constitutes approximately 95% of neoplasms in the US?

Answer 37

Sporadic malignant neoplasms

Question 38

Top 4 most common types of lung cancer

Answer 38

Adenocarcinoma (38%)
Squamous cell carcinoma (20%)
Small cell carcinoma (14%)
Large cell carcinoma (3%)

Other (25%)

Question 39

Parenchyma is generally associated with:

Stroma is generally associated with:

Answer 39

Carcinomas

Sarcomas

Question 40

Which tumors grow fast? Slow?

Answer 40

Malignant tumors grow fast, benign tumors grow slowly.