Benign tumor characteristics
Intact skin surface
Expansile growth
Capsule
Homogenous Cut surface
malignant tumor characteristics
Invasive growth
Ulceration of skin
Lymphatic invasion
Inhomogenous cut surface
Necrosis
Hemorrhage
Vessel invasion
Histopathologically, malignant tumors demonstrate
cellular atypia
Features of Cellular Atypia
- Pleomorphism (variation in cell size and shape, tumor giant cells)
- Increased nucleus/cytoplasm ratio
- Abnormal nuclear morphology; nuclear hyperchromatism (darker in color)
- Prominent nucleoli
- Mitoses (increased number and presence of atypical mitotic figures)
- Loss of polarity
Dysplasia
- Literally means "disordered growth"
- Principally in epithelia
- Constellation of changes including loss of uniformity of the individual cells and loss of
their architectural orientation
Metaplasia
One differentiated cell type (epithelial or mesenchymal) is replaced by another cell type.
The most common: columnar to squamous
what is the most common metaplasia?
columnar to squamous
T/F Epithelial metaplasia , double-edged sword and, in most circumstances
persistent epithelial metaplasia (columnar to squamous, seen in the lung), may
initiate malignant transformation (dysplastic changes).
True
Hyperkeratosis
Thickening of the skin caused by a mass of keratinocytes
Hyperplasia
increase in number of cells
dysplasia is a precursor of a (benign/malignant) process
malignant
Dysplasia is a "______________" lesion
premalignant
Mild Epithelial Dysplasia