|
|
|
|
|
|
|
| Squamous Cell Carcinoma | ||
| Etiology •There is a correlation between the incidence of squamous cell carcinoma (SCC) and prolonged exposure to ultraviolet radiation. •It is particularly common in white-skinned individuals exposed to sunlight, as in Australia. •In addition, inherited disorders resulting in DNA repair defects result in an increased incidence of squamous cell carcinoma. •Chronic underlying inflammation, such as a sinus draining into the skin surface, has also been associated with an increased incidence of squamous cell carcinoma. | ||
| Pathogenesis •Both environmental (UV exposure) and genetic factors play roles in the pathogenesis of SCC of the skin., | ||
| Epidemiology •Represent 20% of non-pigmented malignancies of the skin. •Somewhat more common in men. | ||
| General Gross Description •Grossly, these often present initially as lumps with a tendency to ulcerate over the central region. •They can be slowly growing, relatively indolent tumors, or somewhat more rapidly growing tumors. •Examples: | ||
| General Microscopic Description •Histologically, the SCC of skin is a typical squamous cell carcinoma, with a tendency to form nests of cells lying in the underlying dermis, detached from the overlying epithelium. •The nests are characterized by the presence of a basal cell layer and a stratum spinosum which is a distinctive and diagnostic feature of squamous cell carcinoma. •Another diagnostic feature is the formation of "keratin pearls", concentric accumulations of keratin at the centers of dysplastic nests of squamous cells. •The level of differentiation may extend quite widely with perfectly benign appearing nests lying in the dermis to extremely anaplastic cells. •Examples: | ||
| Clinical Correlation •Squamous cell carcinomas are tumors of skin with a distinct tendency to be both locally invasive and in untreated cases, to spread primarily to local lymph nodes and from there to other regions of the body. | ||
| References • Cotran RS, Kumar V, Robbins SL: Robbins Pathologic Basis of Disease. 5th edition. Philadelphia, W.B. Saunders, 1994, pp. 1186 • Harrison's Principles of Internal Medicine, 13th Edition: Isselbach et. al. (eds). New York, McGraw-Hill, 1994, pp. 1866. Please be patient during transfer. Medline will open in a new window. To return, close the Medline Window Squamous Cell Carcinoma
| Synopsis by: T.V.Rajan, M.D., Ph.D. (T01000M80703)[525]
| |
|
|
|
|
|
|