NeoplasiaEpithelial tumours

Benign epithelial tumours;

Present in two ways:

Sheet of epithelial cells covering a surface (Papilloma) Solid masses of cells separated in to groups by stromal tissues (adenomas).

• Papillomas;

Wart like or papillary out growths

Pedunculated,

Sessile,

Villous.

Three types according to the nature of the epithelial involvement;

• Squamous cell papilloma.

• Transitional cell papilloma

• Columnar cell papilloma

Squamous cell papilloma.

Skin, tongue, larynx, anus

Histology: Acanthosis,

Hyperkerotosis,

Parakeratosis.

Transitional cell papilloma

• See in the bladder (resembles sea anemone) Recurrence is high Haematuria

•Columnar cell papilloma; can see places with col ep

• Other epithelial lesions(heterogeneous group);

Epithelial naevus (developmental) Verruca vulgaris (virul) Solar keratosis (sun burns) Basal cell papilloma (seborrhoeic keratosis)

Basal cell papilloma• Soft

• Well demarcated

• Raised

• Darkly stained skin lesion.

Histology:

Horn cysts

Basal cell with ovoid vesicular nucleus

Cytoplasm consist of pigmented granules

Adenoma;• Consist of dense collection of acini lined

with cuboidal or columnar epithelium.

• In endocrine gland adenomas no acini can be seen, (polygonal or spheroidal cells arranged in solid groups)

• Deep tissue adenomas spherical mass of cells with a capsule.

Benign connective tissue tumours;• The neoplastic over growth of the tissue (eg

muscle fibroblasts bones etc) and the individual cells or groups of the cells separate each other by intercellular substance secreted by tumour cells them selves.

• The consistency of the tumour depends on the quality and quantity of the intercellular substance.

• Poorly delineated stroma consist of blood vessels and connective tissues. It merge with the neoplastic tissues.

Fibroma

• Not a common tumour

• Circumscribed collection of fibroblast

• Collagen interlaced (Soft or hard depend on collagen)

Eg Skin, Stomach, Ovary etc

Myxoma:• It is a well circumscribed, oval translucent and grey

colour, Cut surface; Glistening slimy.

• Scattered stellate cells disposed in connective tissue mucin in which net work of reticulin fibres.

• Found in jaws, heart, and associated with other connective tissues

• Origin may be from undifferentiated fibroblasts or primitive mesenchymal cells

Epithelial malignancies

• Epthelial Dysplasia amd squamous cell carcinomas

Basal cell carcinoma• Seen in the skin of dark people• Face is the commonest site• Punched out ulcer• Locally invasive • Arise from basal cells• HistologyCoins or sheets of uniform basophilic cells.Cells are closely packed and polyhedral in shapePeripheral cell layer of the coins are columnar/cuboidelNuclei are ovoid and basophilic, and palisading