Neoplasm (Tumour) - Common Types of Neoplasm Components of Tumours
Neoplasm
Means new growth and the new growth produced is called Tumour and Neoplasm. Neoplasm is amass of tissues formed as a results of abnormal excessive, unco ordinates, autonomous and purposeless proliferation of cells.
Types of Neoplasm and Tumour
- Benign Tumour
- Malignant Tumour
Benign Tumour – When tumour are slow growing and localized without causing much difficulty to the host genigntumour have suffix – oma.
Malignant Tumour – Is proliferates rapidly spreads throughout the body and may eventually causes death of host malignant is commonly know as cancer.
Two basic Components of all Tumours are -
Parenchyma – Its is comprised by proliferating tumor cells, Parenchyma determine the nature of the tumor.
Supportive Stroma – It is composed of fibrous connective tissues and blood vessels. Its provided framework on which parenchymal tumour cells grow.
Tumours Classified as -
- Mixed
- Teratomas
- Blastomas
Characteristics of the Tumour -
- Rate of growth
- Clinical Features
- Microscopic Features
- Direct Spread
- Distant Spread
Mechanism of Cancer Development -
- Activation of Oncogenes
- Suppression of Apoptotic Genes
- Inhibition of Tumour Suppressor Genes
Activation of Oncogenes – Transforming virus – infect host cells – proto oncogenes – oncogenes – cancer.
Pathophysiology of Neoplasm and Tumour
Ionization , Radiation causing agents
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Cells without p53
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No DNA repair
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No Cell cycle arrest
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Mutated Cells
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Un Controlled division
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Cancer
Defense Mechanism Against Tumour
- Tumour Antigens – TSA (Tumour Specific Antigen, Tumour Associated Antigen (TAA), Antitumour Effector Mechanism and Immunosurveillance
- Antitumour Effector Mechanish
- Immunosurveillance
Clinical Fetaures of Tumours and Neoplasm -
- They effects of tumour on host.
- Cancer Cachexia
- Paraneoplastic syndrome
- Grading of tumour
Diagnosis of Tumours – Histological Methods, Cytological Methods, Immuno Histochemistry, Electron Microscopy, Biochemical Assays.