Neoplasms Chapter 3 Terminology to neoplasms & tumors - PowerPoint Presentation

Slide1

Neoplasms

Chapter 3Slide2

Terminology to neoplasms & tumors

Neoplasm (neo=

new,plasm

=growth)

Tumors may be defined as swelling or as a neoplasm. Remember Not all neoplasms form tumors.

Ex: Leukemia (

Leuk

=white,

emia

=blood) is a malignant disease of the bone marrow that causes an increase in white blood cells and might not form distinctive tumors.

Likewise, not all tumors are neoplasms. Ex: Hematoma (

hemat

=blood,

toma

=tumor) is a large tumor or swelling filled with blood, commonly known as a bruise.Slide3

Classifications of Neoplasms

Two of the most common ways to classify neoplasms are according to

The appearance and growth pattern and

Tissue of origin, or type of body tissue from which they grow

Neoplasm tumors can be benign or malignant.Slide4

Malignant & benign neoplasms

Benign- are confined to a local area and do not spread. Commonly called tumors and are generally harmless unless they are growing in a confined space such as the brain.

Malignant- are deadly because they exhibit characteristics of invasion and metastasis.

Invasion refers to the spreading of the neoplasms into local or surrounding tissue.

Metastasis- the spread of the neoplasm to distant sites. Commonly known as cancer.Slide5

Tissue of origin

Neoplasms will be classified or named according to the tissue from which they grow along with the suffix, “

oma

”, for tumor.

A benign tumor will have suffix “

oma” added AFTER the name of the TISSUE. Ex: Lipoma, a benign tumor of fatty tissue.A malignant tumor will have the term “Carcinoma” or “Sarcoma” added to the name of its tissue.Slide6

Epithelial tissue (skin or gland)

A benign tumor of epithelial tissue such as a gland would be adenoma; if it is malignant then the name becomes adenocarcinoma.

Carcinoma denotes the largest group of malignant neoplasms, indicating a tumor of epithelial tissues found on external or internal body surfaces.Slide7

Connective tissue (bone, muscle, or fat)

A benign tumor of connective tissue such as bone would be

osteoma

; if it’s a malignant neoplasm it would be osteosarcoma.

Sarcoma- is the term used if the neoplasm is from connective tissue such as muscle, fat, and bone.

Sarcomas are less common than carcinomas, but spread more rapidly and are highly malignant.Slide8

Lymphatic or blood-forming tissue

Lymphomas and leukemia's are malignant neoplasms of lymphatic and blood forming organs and lymphatic tissues, respectively.

These malignant neoplasms do not have benign counterparts. All leukemia's and lymphomas are malignant.Slide9

Other tissues

Some tissues do not follow the typical pattern.

For example, malignant melanoma, a malignant neoplasm of melanocytes (skin cells).

Glioma refers to all tumors of the glial cells of the brain. Don’t fit the classification system.

Are benign in appearance and do not metastasize, but are malignant because most are fatal.Slide10

Growth of benign and malignant neoplasms

Normal cells grow and function for a purpose regulated by several factors.

Built in genetic program regulates growth pattern.

Normal cell growth is limited by contact with other cells.

When two normal cells come together they tend to stick together sending a signal called contact inhibition, telling cells to stop growing.

3. After Normal cell growth, cells start to perform specialized functions called differentiation.Slide11

Benign neoplasm growth

Benign neoplasm tumors might have some normal structure and function, similar to their origin.

They are encapsulated or covered with capsule like material, making removal or excision easier.

Have limited growth potential and are slower growing that metastasized neoplasms.

They are expansive (grow and enlarge in the area) but are not invasive or

metastic.Slide12

Benign neoplasm growth

Benign neoplasms not being metastatic does not mean they are harmless.

The presence and growth of any tumor can obstruct passageways such as those in the digestive an respiratory tact, leading to difficulty eating or breathing.

Tumors can also put pressure on nerves, causing pain and loss of sensation. Can also affect glands causing over and under secretion of hormones, and pressure on brain causing cell and tissue death.Slide13

Malignant neoplasm growth

Have a growth pattern that has no purpose and is uncontrollable. Neoplastic cells grow autonomously or independent of growth factors.

These cells to not follow cell regulation such as contact inhibition.

Malignant neoplastic cells do not have the structure or function of the cells of their origin, and do not look alike as benign tumors do.

Structure is not uniform but haphazard and inconsistent, are not differentiated and do not have specialized functions.Slide14

Malignant neoplasm growth

The surface area of malignant neoplasms are not encapsulated, Rather it is more crab like in appearance, with multiple claw like extensions invading surrounding tissue.

Also malignant tumors metastasize to distant areas of the body, and are fast growing.

Metabolism of cancerous cells are aimed to rapid reproduction and growth, outgrowing normal cells, leading to increase for the need of nutrients and oxygen.Slide15

Malignant neoplasm growth

To meet the need of nutrients, malignant cells cause

Angiogenisis

(

ango

=vessel, genisis=growth or new growth of blood vessels)This occurs to increase of blood flow, providing increased nutrients to the neoplasm allowing the continuation of rapid uncontrolled growth.At this point, normal cells are deprived of needed nutrients, causing the individual to appear thin, frail and weak, a condition called cachexia.

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