PathophysiologyUnit 1

Neoplasms

Pathophysiology - Borders - Spring 2012

Neoplasms

• TEST• Next class• Neoplasms and Cellular Functions• Multiple choice • Use this PPT and highlighted Notes• This longer PPT will be uploaded on

my website to replace the shorter one that was used for the quiz

Prokaryotic—no nucleus, circular DNA, ribosomes

Eukaryotic—larger, nucleus, linear chromosomes, membranous organelles

Cell types

Eukaryotic Cells

• Have numerous internal structures

• Various types & forms• Plants, animals, fungi, protists

• Multicellular organisms

Cell Parts and FunctionsCell Membrane

Protects the cell

Lets things in and out of the cell

Location: around the cell

Nucleus

Control center

Location: inside the cell,

near the center

Cell Parts and FunctionsNucleolus (Nucleoli)Makes ribosomesLocation: inside the nucleus (dark spot)

Nuclear MembraneProtects nucleusLets things in/out of nucleus (pores)Location: around nucleus

cell

Cell Parts and Functions

Mitochondria

Makes energy/powerhouse

Location: in cytoplasm

Golgi Bodies/Apparatus

Packages and secretes

(gets rid of) waste

Location: in cytoplasm

Mitochondria

GOLGI APPARATUS

Cell Parts and Functions

Endoplasmic Reticulum (E.R.)

Transports materials and sends messages to all parts of the cell

Two types: smooth and rough (has ribosomes)

Location: attaches from cell membrane to nuclear membrane

Rough E.R.

Cell Parts and Functions

Ribosome

Makes proteins

Location: in cytoplasm or

Attached to E.R.

Vacuole

Stores food and water

Location: in cytoplasm

Vacuole

Cell Parts and Functions

Lysosome

Contains digestive enzymes

Destroys bacteria, old cell parts…

Location: in cytoplasm

Centrioles

Helps the cell to divide

Location: in cytoplasm

Cell Parts and Functions

Cytoplasm

Gel-like substances, holds all

Organelles in cell

Location: in cell

Chromatin/Chromosomes

Contains genetic information/traits

Location: in nucleus

Cell Parts and Functions

CiliaShort hair-like projections Used for movementLocation: outside of cell

FlagellaLong whip-like tailUsed for movementLocation: outside of cell

FLAGELLA

Characteristics of Normal Cells

• Reproduce themselves exactly• Stop reproducing at the right time• Stick together in the right place• Self destruct if they are damaged• Become specialized (differentiated) or 'mature'

Characteristics of Cancer Cells

• Cancer cells don't stop reproducing• Cancer cells don't obey signals from other cells• Cancer cells don't stick together• Cancer cells don't specialize or differentiate , but stay immature

Comparing Normal and Cancer Cells

Neoplasms or Tumors

• Cellular growth that is no longer responding to normal body controls• Cells continue to reproduce when there is no need for them• The excessive growth deprives other cells of nutrients

Characteristics of Benign Tumors

• Usually consist of differentiated cells that reproduce at a higher than normal rate

• Often encapsulated and expands but does not spread• Usually freely moveable on palpation• Tissue damage results from compression of adjacent structures

such as blood vessels• Not considered life threatening unless in area such as the brain

where pressure can become critical

Characteristics of Malignant Tumors

• Usually made-up of undifferentiated, nonfunctional cells that do not appear organized

• Tend to reproduce more rapidly than normal• Cells have lost cellular connections with each other• Reproduction is not inhibited in presence of similar cells

Terminology

• Tumor : Pathologic disturbance of growth, characterized by excessive and unnecessary proliferation of cells

Terminology

• Hamartoma : Excessive but focal overgrowth of cells and tissues native to the organ in which it occurs. Cellular elements are mature, but do not produce normal architecture• Hamartroma of lung• Angiomas• Pigmented nevi

Terminology

• Choristoma (Heterotopia) : Normal cells or tissues, that are present in abnormal locations• Pancreatic cells in the wall of stomach or intestine• Nests of adrenal cells in kidney , lung or ovaries

Terminology

• Neoplasms : Persistent , abnormal and relatively autonomous proliferation of cells occurring as a result of permanent cellular defect that is passed to

the progeny.

Types of Neoplasms

• Benign: localized and amenable to surgical removal; patient usually survives

• Malignant: invasive tumor capable of destroying structures and spread to distant sites (metastasis); may result in early death of the patient

Types of Neoplasms

• The terms “benign” and “malignant” describe the biologic behavior of a tumor

• The biologic behavior is characterized by degree of differentiation of the tumor , rate of growth (and rate of cell death) , infiltration of surrounding tissue, and dissemination to distant sites

Examples of Malignant Tumors

• Sarcoma (mesenchymal derivation: fibrosarcoma, chondrosarcoma)

• Carcinoma (epithelial derivation: adenocarcinoma, squamous cell carcinoma)• Squamous• Adeno• Transitional

• Lymphoma/leukemia

Examples of Benign Tumors

• Epithelial• Adenoma: benign glandular tumor• Papilloma : benign surface epithelial tumors• Polyp : benign tumor projecting over mucosal

surface• Cystadenoma : benign epithelial tumor forming

hollow cystic mass

Different Kinds of Cancer

Lung

Breast (women)

Colon

BladderProstate (men)

Some common sarcomas:Fat

Bone

Muscle

Lymphomas:Lymph nodes

Leukemias:Bloodstream

Some common carcinomas:

leiomyomas

adenoma

adenocarcinoma

carcinoma

Differentiation

• Well-differentiated tumors contain cells that resemble the normal cells of origin

• Poorly-differentiated or undifferentiated tumors contain cells that do not resemble their normal counterparts (ancillary studies may be needed to determine the cell of origin)

well-differentiated

poorly-differentiated

Differentiation

• Benign tumors are composed of well-differentiated cells.• Malignant tumors are characterized by a wide range of cellular

differentiation.

Rate of Growth

• In general, benign and well-differentiated malignant tumors have a slower rate of growth than moderately-differentiated and poorly-differentiated malignant tumors.

• There are exceptions. Blood supply, site, and hormonal stimulation are factors that can affect the growth rate of tumors.

Invasion

• Benign tumors usually grow by slow expansion.

• Malignant tumors usually infiltrate and may destroy surrounding tissue (cell surface and the extracellular matrix play an important role).

Functional characteristics

• Benign tumors are more likely to function• Hormonal production can be unregulated• Inappropriate production of hormones by

different type of cells• Abnormal receptor and antigenic

expression

Metastasis

• indicates malignancy• a discontinuous spread of the tumor

metastatic ovarian carcinoma

MRI: metastatic adenocarcinoma

metastatic adenocarcinoma

meningioma

basal cell carcinoma

melanoma

cytology smear: adenocarcinoma

Summary

• Neoplasm- an abnormal mass of tissue which has lost its responsiveness to growth controls

• Benign neoplasms tend to be slow-growing, well-differentiated tumors which lack the ability to metastasize

• Benign neoplasms, in general, remain localized and are amenable to surgery

Summary

• Malignant neoplasms tend to be fast-growing lesions which invade normal structures

• Malignant neoplasms vary in the degree of differentiation

• Malignant neoplasms are capable of metastasis