Tumors (Neoplasia)
Neoplasia (tumors) are abnormal tissue proliferations, which develop exceeding normal tissue,
uncoordinated with it. This uncontrolled tissue growing may continue even after cessation of the etiologic
factor (self-maintained). The structure of a tumor (neoplasia) : parenchyma (tumor cells derived from
previously normal cells) and stroma (vessels and connective tissue), in variable proportions.
Classification and nomenclature of tumors
| Tumours composed of one parenchymal cell type |
Benign |
Malignant |
| 1. Epithelial tumours |
| Stratified squamous epithelium |
Squamous cell papilloma |
Squamous cell carcinoma |
| Basal cells of skin or adnexa |
Seborrheic keratosis |
Basal cell carcinoma |
| Glands or ducts |
|
|
| Respiratory tract epithelium |
|
Bronchogenic carcinoma |
| Neuroectoderm |
Melanocytic nevus |
Malignant melanoma |
| Renal epithelium |
Renal tubular adenoma |
Renal cell carcinoma |
| Liver cells |
Liver cell adenoma |
Hepatocellular carcinoma |
| Bile ducts |
Billiary adenoma |
Bile duct carcinoma |
| Urinary tract epithelium (transitional) |
Transitional cell papilloma |
Transitional cell carcinoma |
| Placental epithelium - gestational trophoblast |
Hydatidiform mole |
Gestational choriocarcinoma |
| 2. Mesenchymal tumours |
Conjunctive tissue and derivatives :- fibroblasts
- lipoblasts
- chondroblasts
- osteoblaste
|
|
|
Endothelium and relative tissues :- blood vessels
- lymphatic vessels
- synovia
- mesotelium
-
- meninge
|
-
- Hemangioma
- Lymphangioma
-
- Solitary fibrous tumour of the pleura
- Meningioma
|
-
- Angiosarcoma
- Lymphangiosarcoma
- Synoviosarcoma
- Malignant mesothelioma
-
- Invazive meningioma
|
Blood cells :- hematopoietic cells
- lymphoid tissue
|
|
|
| Muscle fibers : |
|
-
- Leiomyosarcoma
- Rhabdomyosarcoma
|
| Tumours with different types of cells from the same germ layer - mixed tumours |
Benign |
Malignant |
| Salivary glands |
Pleomorphic adenoma (Mixed tumour of salivary gland origin) |
Malignant mixt tumour of salivary gland origin |
| Breast |
Fibroadenoma |
Malignant cystosarcoma phyllodes |
| Nephroblastem (metanephric blastema) |
|
Nephroblastoma (Willms' tumor) |
| Tumours with different types of cells derived from more than one germ layer - teratogenous |
Benign |
Malignant |
| Totipotential cells in gonads or in embryonic rests |
|
- Immature teratoma
- Teratocarcinoma (Embryonic carcinoma)
- Endodermal sinus tumour
- Non-gestational choriocarcinoma
|
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