Basic Concepts of Neoplasia (small group)

Question 1

Define tumor.

Answer 1

Swelling

A very general term denoting the formation of a mass that encompasses neoplasms as well as non-neoplastic lesions

Question 2

Define neoplasm.

Answer 2

“new formation”

An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the change

Question 3

Define neoplasia.

Answer 3

The process of abnormal, autonomous proliferation of cells

Question 4

Define benign. (4)

Answer 4

A neoplasm that grows locally without invasion or metastasis
May grow slowly and permit long survival
Usually highly differentiated
Usually less dangerous than malignant neoplasms, but may cause clinical problems

Question 5

Define malignant.

Answer 5

Denotes a neoplasm that can invade and/or metastasize

Question 6

Define invasion.

Answer 6

Growth into surrounding tissues, blood vessels, or lymphatics

Question 7

(OBJ) Define metastasis. Discuss the four required steps for a tumor metastasis to occur.

Answer 7

Denotes growth of cancer cells at a second, separate site

• -Refers to both the secondary cancer and the process
  1. Intravasation (get into bloodstream or lymphatics)
  2. Transport through circulation
  3. Arrest in microvessels of various organs
• -Frequent sites = lymph nodes, liver, and lungs
  4. Extravasation -> formation of micrometastasis -> formation of macrometastasis via angiogenesis/stromal induction

Question 8

Define cancer.

Answer 8

A malignant neoplasm

Question 9

Distinguish primary and secondary neoplasm.

Answer 9

Primary neoplasm: the original neoplasm

Secondary neoplasm: the metastasis or metastases

Question 10

(OBJ) Use the appropriate vocabulary to name carcinomas of various organs.

Answer 10

CARCINOMA: a malignant neoplasm of epithelial cell origin
–Suffix -oma for benign, -carcinoma for malignant

–ADENOcarcinoma: carcinoma arising in glandular tissue

Question 11

(OBJ) Use the appropriate vocabulary to name sarcomas of various organs.

Answer 11

SARCOMA: a malignant neoplasm of mesenchymal cell origin (CT, bone, fat, muscle cells)
–Suffix -oma for benign, -sarcoma for malignant

• -FIRBOsarcoma: malignant neoplasm of fibroblasts
• -LIPOsarcoma: malignant neoplasm of fat cells
• -LEIMYOsarcoma: malignant neoplasm of smooth muscle cells
• -RHABDOMYOsarcoma: malignant neoplasm of striated muscle cells
• -OSTEOsarcoma: malignant neoplasm of bone

Question 12

Define differentiation.

Answer 12

The extent to which cells resemble comparable normal cells, both morphologically and functionally

Question 13

Define anaplasia. (2)

Answer 13

Failure of cells to differentiate to normal adult phenotype -> wild looking cells with weird nulcei
Characteristic of malignant transformation, so important to recognize

Question 14

(OBJ) Distinguish a hamartoma (6) from a teratoma (3).

Answer 14

HAMARTOMA: a mass, the cells of which are normally present in that particular organ, but are in an abnormal arrangement, often with one cell type predominating

• -NOT a neoplasm; instead a disorganization of benign, normally occurring elements (a malformation)
• -All components are mature and fully differentiated
• -Do not grow
• -Probably present from birth; become calcified over time
• -Generally not harmful, unless their location is harmful

TERATOMA: a benign neoplasm with components representing all three germ layers

• -Derives from germ cells
• -Characteristically in ovaries or testes

Question 15

Define pleomorphism.

Answer 15

Variation in cellular appearance, size, and shape WITHIN a tumor

Question 16

Define atypia.

Answer 16

Morphologically different form the normal cell

–Nuclei may be larger, darker, and have irregular nuclear contours

Question 17

Define acinar.

Answer 17

Glandular, but denoting a secretory unit rather than a duct

Question 18

Define papillary.

Answer 18

Forming finger-like growths with a central stalk and an epithelial surface

Question 19

Define polyp.

Answer 19

A mass protruding from a surface

Question 20

Define dysplasia. (3)

Answer 20

Some degree of loss of normal differentiation of cells and tissues

• -Premalignant change (reversible!)
• -ONLY applies to epithelia, NOT mesenchymal tissues

Question 21

Define stroma. What is desmoplastic stroma?

Answer 21

Stroma: the vascular CT supporting the parenchyma of an organ, or supporting the proliferating cells of a neoplasm
–Desmoplastic stroma: a stroma dominated by dense fibrous tissue (looks white)

Question 22

(OBJ) Distinguish cell changes that are adaptive from those that are characteristic of neoplasia. (3+4)

Answer 22

Adaptive: controlled, physiologic, reversible

• -Hypertrophy
• -Hyperplasia
• -Atrophy
• -Metaplasia

Neoplastic: autonomous, pathologic, irreversible

Question 23

(OBJ) Define carcinoma in situ. (3)

Answer 23

A lesion which is histologically malignant, but has NOT yet invaded
Recognized histologically because of severe dysplasia in the cells
Regarded as premalignant/precancerous change

Question 24

(OBJ) List three features that are characteristic of benign neoplasms and three that are characteristic of malignant neoplasms.

Answer 24

Benign:

• -Localized
• -Circumscribed
• -Well differentiated

Malignant:

• -Invasion
• -Metastasis
• -Usually show loss of differentiation

Question 25

(OBJ) Discuss the pathological changes occurring in uterine cervical epithelium as it passes from normal to invasive carcinoma.

Answer 25

HPV infection -> cells undergo molecular and morphological changes - -Morphological changes are graded as low-grade or high-grade - -Low-grade dysplasia can -> high-grade dysplasia or regress or revert to normal. Complex interaction between the dysplastic process and the host - -Host “wins”, the dysplasia regresses - -Genetic changes “win”, the dysplasia --> carcinoma Dysplasia and anaplasia are part of a continuum (mild dysplasia -> severe dysplasia -> anaplasia) - -Low-grade dysplasia is morphologically closer to normal - -High-grade dysplasia is closer to being cancer - -Severe dysplasia = premalignant change - -Anaplasia = characteristic of some malignant neoplastic cells.

Question 26

Differentiate pedunculated colon polyps from sessile colon polyps.

Answer 26

Pedunculated: hanging off of a long stalk Sessile: flattened, no stalk