At the end of these two lectures you should be able to:-
(1) Understand the concept of neoplasia
(2) Define neoplasia
(3) Understand the nomenclature of neoplasia
(4) Characterised benign & malignant neoplasm
(5) Differentiate between benign & malignant neoplasm
(6) Characterised malignant cells & understand anaplasia
(7) Classify neoplasia
(8) Define “local” & “metastatic” spread
(9) Discuss the route of metastatic spread and principles establish to work out the possible modes of spread of common malignancies
(10) Define “grade” and “Stage” of a tumor and discuss the principles upon which it is based.
(11) To learn the effects of the tumor on the host, understand the Paraneoplastic syndrome and know the Laboratory diagnosis of the tumor.
Definition:
A neoplasm is an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissue and persists in the same manner after cessation of the stimuli which evoke the changes.
CLASSIFICATION OF TUMORS
No single classification is satisfactory. The following bases of classification may be recognized.
1. Naked-eye appearance, including the organ of origin.
2. Histogenetic (including embryological considerations)
3. Histological
4. Behavioral
5. Etiological
6. Functional
(1) Naked-eye appearance-Annular, Fungating (cauliflower), Schirrous, Encaphloid (medullary), Mucoid etc.
(2) Histogenetic- Cell of origin i.e. epithelial or connective tissue
Difficulties- Undifferentiated tumor
1. Tumor metaplasia
2. Debatable cell/tissue of origin
3. Origin from highly specialized cell/tissue
(3) Histological- Cell may not resemble any normal tissue i.e. anaplastic
When the tumor is so undifferentiated as to defy recognition of its site of origin
Anaplastic tumor may be difficult to differentiate- epithelial or connective tissue origin
(4) Behavioral- Benign and