Neoplasia 1

NEOPLASIA

• Neo – new

• Plasia – growth

• Neoplasia - new growth

• Oncology – study of neoplasia

• Oncos – tumor

• Ology – study

• Neoplasia - new growth, non-cancerous or cancerous.

• Pre-Cancerous Lesions.– HYPERPLASIA - excess proliferation leading to an increase in

number of cells & increase in size of the tissue/organ. Causes, chronic irritation, excess hormones.

– HYPERTROPHY - increase in size of cells & tissue without any increase in number of cells. It is due to increased functional activity of any tissue.

– ATROPHY - simple decrease in size of cells leading to shrinkage of tissues & organs.

– METAPLASIA - change of one type of tissue to another type of different tissue at a place. There may be associated hyperplasia. Usual cause is chronic irritation.

– DYSPLASIA - disordered cellular development leading to abnormal & variable number of cells with change in shape, arrangement & increased mitosis. It is a Pre-malignant condition.

NEOPLASIA

• Neoplastic Growth - abnormal proliferation of cells in a tissue or organ leading to new growth formation.

• Features:– Progression.– Purposeless.– Regardless of surrounding tissue.– Not related to body needs.– Parasitic in nature.

• Classification.– Clinical - (behavior & morbidity) - Benign & Malignant.– Histological - according to origin from type of tissue.

• Epithelia & Glands - (omas & carcinoma)• Mesodermic / Connective tissue – (omas & sarcomas)• Neural Ectoderm – (according to type of neural cells)• Hemopoietic tissue – (myeoldyspalsia & leukemia)• Lymphoid tissue – (lymphoma & lymphosarcoma)

NEOPLASIA

Nomenclature

NEOPLASIA(CLINICAL FEATURES)

FEATURES BENIGN MALIGNANT

Rate of Growth Slow progression Usually rapid progress

Shape ofGrowth

Well demarcatedoften encapsulated

Irregular illdefined &non-capsulated

Relationship tosrrounding

Merely compressnormal tissues

Invade & destroy normaltissues

Spread ofGrowth

Remains locallized Local & distant spreadvia, lymph, blood &serous cavities –METASTASIS.

NEOPLASIA(Classification of Tumor Cells according to their Appearance)

• DIFFERENTIATED

• Similar to their parent of origin

in shape & structure.

• Evidence of normal function.

• Nuclei of same size & shape.

• Infrequent Mitotic figures.

• Signifies a Simple Growth.

• Course & Prognosis is Good

• UNDIFFERENTIATED

• Shape & structure differ from

original cells.

• Abnormal function.

• Abnormal Nuclear

configuration & appearance.

• Abnormal Mitosis.

• Signifies a Malignant Growth.

• Course & Prognosis is Poor.

CARCINOGENESIS

Physical agents.Chemical agents.

Viruses.

Normal Cell Susceptible cell

Mutant cellLoss of identity

Increased mitosis

Co-factorsHereditary & Age

EnvironmentHormonal StatusChronic Irritation

Host reaction successfulRestoration of Normal

cells

Host reaction failurecontinued proliferation

MALIGNANCY

CARCINOGENESIS

Progression of Neoplasia

Progression of Neoplasia

Progression of Neoplasia

Neoplasia Diagnosis

Neoplasia Diagnosis