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Varicella zoster virus
Poxvirus (Smallpox and Molluscum contagiosum)
Herpes simplex virus
Malassezia (Tinea versicolor and Seborrhoeic dermatitis)
Pediculus humanus and Phthirus pubis (Lice)
Sarcoptes scabiei (Scabies)
Human herpesvirus 6 (Roseola)
Varicella zoster virus
Human herpesvirus 8 (Kaposi sarcoma)
Pigmentation skin disorders: Pathology review
Acneiform skin disorders: Pathology review
Papulosquamous and inflammatory skin disorders: Pathology review
Vesiculobullous and desquamating skin disorders: Pathology review
Skin cancer: Pathology review
Bacterial and viral skin infections: Pathology review
Viral exanthems of childhood: Pathology review
0 / 40 complete
0 / 13 complete
melanomas and p. 497
IFN- αfor p. 201
common metastases p. 202
immunohistochemical stain for p. 220
nomenclature for p. 225
oncogene p. 222
origin of p. 225
tumor suppressor gene p. 222
recombinant cytokines for p. NaN
of skin p. 497
sunburn and p. 496
vemurafenib for p. 449
Samantha McBundy, MFA, CMI
Skin cancer is an uncontrolled growth of cells within the skin.
There are three main types: basal cell carcinoma, squamous cell carcinoma, and melanoma.
Some skin cancers can spread to other locations in the body and can be fatal, as seen with singer-songwriter Bob Marley, who died shortly after being diagnosed with melanoma.
The skin is divided into three layers--the epidermis, dermis, and hypodermis.
The hypodermis is made of fat and connective tissue that anchors the skin to the underlying muscle.
Just above is the dermis, which contains hair follicles, nerves and blood vessels.
And just above that, the outermost layer of skin, is the epidermis.
The epidermis itself has multiple cell layers that are mostly keratinocytes - which are named for the keratin protein that they’re filled with.
Keratin is a strong, fibrous protein that allows keratinocytes to protect themselves from getting destroyed, when you rub your hands through the sand at the beach.
Keratinocytes start their life at the deepest layer of the epidermis called the stratum basale, or basal layer, which is made of a single layer of small, cuboidal to low columnar stem cells that continually divide and produce new keratinocytes that continue to mature as they migrate up through the epidermal layers, flattening out to a pancake-like squamous shape as they ascend.
But the stratum basale also contains another group of cells - melanocytes, which secrete a protein pigment, or coloring substance, called melanin.
Melanin is actually a broad term that constitutes several types of melanin found in people of differing skin color.
These subtypes of melanin range in color from black to reddish yellow and their relative quantity and rate at which they are metabolized define a person’s skin color.
When keratinocytes are exposed to the sun, they send a chemical signal to the melanocytes, which stimulates them into making more melanin.
The melanocytes move the melanin into small sacs called melanosomes, and these get taken up by newly formed keratinocytes, which will later metabolize the melanin as they migrate into higher layers of the epidermis.
Skin cancer is a type of cancer that develops in the cells of the skin. Three main types of skin cancer are basal cell carcinoma (the most common), squamous cell carcinoma (the second most common), and the least common but most deadly, melanoma. Risk factors for skin cancer include exposure to UV radiation, a history of sunburns, fair skin, and a weakened immune system. Diagnosis is made with a tissue biopsy and treatments can include physically removing cells with a high risk of developing into skin cancer. Tumor cells are also commonly removed and treated with radiation, chemotherapy, or immunotherapy.
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