Skin cancer is a malignant growth on the skin which can have many causes. Skin cancer generally develops in the epidermis (the outermost layer of skin), so a tumor is usually clearly visible. This makes most skin cancers detectable in the early stages. There are three common types of skin cancer, each of which is named after the type of skin cell from which it arises. Cancers caused by UV exposure may be prevented by avoiding exposure to sunlight or other UV sources, wearing sun-protective clothes, and using a broad-spectrum sun screen.^{[citation needed]} The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // C00-D48 - Neoplasms (C00-C14) Malignant neoplasms, lip, oral cavity and pharynx (C00) Malignant neoplasm of lip (C01) Malignant neoplasm of base of tongue (C02) Malignant neoplasm of other and unspecified parts of tongue (C03) Malignant neoplasm of gum (C04) Malignant neoplasm of floor of mouth (C05) Malignant neoplasm of... // C00-D48 - Neoplasms (C00-C14) Malignant neoplasms, lip, oral cavity and pharynx (C00) Malignant neoplasm of lip (C01) Malignant neoplasm of base of tongue (C02) Malignant neoplasm of other and unspecified parts of tongue (C03) Malignant neoplasm of gum (C04) Malignant neoplasm of floor of mouth (C05) Malignant neoplasm of... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The International Classification of Diseases for Oncology (ICD-O) is a domain specific extension of the International Statistical Classification of Diseases and Related Health Problems for tumor diseases. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... In medicine, malignant is a clinical term that means to be severe and become progressively worse, as in malignant hypertension. ... Beyond overall skin structure, refer below to: See-also. ... Look up Epidermis in Wiktionary, the free dictionary. ... For malignant tumors specifically, see cancer. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Sunscreen (also known as sunblock, suntan lotion) is a lotion, spray or other topical product that helps protect the skin from the suns ultraviolet (UV) radiation, and which reduces sunburn and other skin damage, ultimately leading to a lower risk of skin cancer. ...

Skin cancers are the fastest growing type of cancer in the United States. Skin cancer represents the most commonly diagnosed malignancy, surpassing lung, breast, colorectal and prostate cancer. More than 1 million Americans will be diagnosed with skin cancer in 2007.^[1]

Risk factors

Skin cancer is most closely associated with chronic inflammation of the skin. This includes:

1. Sunburn or excessive sun damage, especially early in life. UVA & UVB have both been implicated in causing DNA damage resulting in cancer. Sun exposure between 10AM and 4PM is thought to be most harmful. Natural (sun) & artificial UV exposure (tanning salons) are associated with skin cancer.
2. Chronic non-healing wounds, especially burns. These are called Marjolin's ulcers based on their appearance and can develop into squamous cell carcinomaand.
3. Genetic predisposition, including "Congenital Melanocytic Nevi Syndrome". CMNS is characterized by the presence of "nevi" or moles of varying size that either appear at or within 6 months of birth. Nevi larger than 20 mm (3/4") in size are at higher risk for becoming cancerous.

Skin can be protected by avoiding sunlight entirely, or wearing protective clothing while outdoors. Skin cancer is usually caused by exposing skin to UV rays excessively. Marjolins ulcer presenting on arm following a burn Marjolins ulcer refers to an aggressive ulcerating squamous cell carcinoma presenting in an area of previously traumatised [1], chronically inflamed [2], or scarred skin [3]. They are commonly present in the context of chronic wounds including burn injuries, venous ulcers... Nevus (or naevus) is a general term that refers to a number of different, usually benign, pigmented lesions of the skin. ...

Types

The most common types of skin cancer are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) which may be locally disfiguring but are unlikely to metastasize (spread to other parts of the body). The most dangerous type of skin cancer is malignant melanoma. This form of skin cancer can be fatal if not treated early but comprises only a small proportion of all skin cancers. Basal cell carcinoma (BCC) is the most common skin cancer. ... Biopsy of a highly differentiated squamous cell carcinoma of the mouth. ... Metastasis (Greek: change of the state) is the spread of cancer from its primary site to other places in the body. ... Melanoma is a malignant tumor of melanocytes. ...

More rare types of skin cancer include:

• Dermatofibrosarcoma protuberans
• Merkel cell carcinoma
• Kaposi's sarcoma

Dermatofibrosarcoma protuberans (DFSP) is a rare neoplasm of the dermis layer of the skin, and is classified as a sarcoma. ... Merkel cell cancer, also called Merkel cell carcinoma or trabecular cancer, is a rare and highly aggressive cancer where malignant cancer cells develop on or just beneath the skin and in hair follicles. ...

Prevalence

Skin cancer is an increasingly common condition. This is in part attributed to increased exposure to ultraviolet radiation, which in turn is thought to be caused by the increased popularity of sun tanning (sun bathing).^{[citation needed]} Lighter-skinned individuals are more vulnerable. ^{[citation needed]} In the United States, about one out of every three new cancers arises from the skin. ^{[citation needed]} Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... A suntanned arm showing browner skin where it has been exposed. ... Prism splitting light High Resolution Solar Spectrum Sunlight in the broad sense is the total spectrum of the electromagnetic radiation given off by the Sun. ...

Signs and symptoms

There are a variety of different skin cancer symptoms. These include crabs or changes in the skin that do not heal, ulcers in the skin, discoloration, and changes in existing moles. Beyond overall skin structure, refer below to: See-also. ... Endoscopic images of a duodenal ulcer. ... A mole, technically known as a melanocytic naevus, is a small, dark spot on human skin. ...

• Basal cell carcinoma usually looks like a raised, smooth, pearly bump on the sun-exposed skin of the head, neck or shoulders. Sometimes small blood vessels can be seen within the tumor. Crusting and bleeding in the center of the tumor frequently develops. It is often mistaken for a sore that does not heal.

• Squamous cell carcinoma is commonly a red, scaling, thickened patch on sun-exposed skin. Ulceration and bleeding may occur. When SCC is not treated, it may develop into a large mass.

• Most melanomas are brown to black looking lesions. Signs that might indicate a malignant melanoma include change in size, shape, color or elevation of a mole. The appearance of a new mole during adulthood, or new pain, itching, ulceration or bleeding of an existing mole should be checked.

Basal cell carcinoma (BCC) is the most common skin cancer. ... “Human Head” redirects here. ... A human neck. ... This article is about the body part. ... f you all The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... Biopsy of a highly differentiated squamous cell carcinoma of the mouth. ... Melanoma is a malignant tumor of melanocytes which are found predominantly in skin but also in the bowel and the eye (see uveal melanoma). ...

Treatment

Most skin cancers can be treated by removal of the lesion, making sure that the edges (margins) are free of the tumor cells. These excisions provide the best cure for both early and high-risk disease.

For low-risk disease, radiation therapy and cryotherapy (freezing the cancer off) can provide adequate control of the disease; both, however, have lower overall cure rates than surgery.

Moh's Microsurgery is a technique used to remove the cancer with the least amount of surrounding tissue and the edges are checked immediately to see if tumor is found. This provides the opportunity to remove the least amount of tissue and provide the best cosmetically favorable results. This is especially important for areas where excess skin is limited, such as the face. Cure rates are equivalent to wide excision. Special training is required to perform this technique.

In the case of disease that has spread (metastasized) further surgical or chemotherapy may be required.^[2]

Reduction of risk

Although it is impossible to completely eliminate the possibility of skin cancer, the risk of developing such a cancer can be reduced significantly with the following steps:

• reducing exposure to ultraviolet (UV) radiation, especially in early years
• avoiding sunburns
• avoiding sun exposure during the day (usually from 10 AM to 3 PM), when the sun is highest in the sky
• wearing protective clothing (long sleeves and hats) when outdoors
• using a broad-spectrum sunscreen that blocks both UVA and UVB radiation
• use SPF sun block of at least 50
• reapply sun block every 2 hours and after swimming

Although it is generally accepted that UV exposure is the greatest risk factor in melanoma development, some skeptics say that there is no proven data that links moderate sun exposure with the appearance of melanoma.

Pathology

Squamous cell carcinoma is a malignant epithelial tumor which originates in epidermis, squamous mucosa or areas of squamous metaplasia.

Macroscopically, the tumor is often elevated, fungating, or may be ulcerated with irregular borders. Microscopically, tumor cells destroy the basement membrane and form sheets or compact masses which invade the subjacent connective tissue (dermis). In well differentiated carcinomas, tumor cells are pleomorphic/atypical, but resembling normal keratinocytes from prickle layer (large, polygonal, with abundant eosinophilic (pink) cytoplasm and central nucleus). Their disposal tends to be similar to that of normal epidermis: immature/basal cells at the periphery, becoming more mature to the centre of the tumor masses. Tumor cells transform into keratinized squamous cells and form round nodules with concentric, laminated layers, called "cell nests" or "epithelial/keratinous pearls". The surrounding stroma is reduced and contains inflammatory infiltrate (lymphocytes). Poorly differentiated squamous carcinomas contain more pleomorphic cells and no keratinization.^[3] ... This page is a candidate to be copied to Wiktionary. ... Eosinophilic is a technical term used by histologists. ... Epidermis is the outermost layer of the skin. ... Epidermis is the outermost layer of the skin. ...

See also

• Cancer
• Mohs surgery
• Sun protective clothing

Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ... Mohs Surgery, created by Dr. Fredrick E. Mohs, is microscopically controlled surgery that is highly effective for common types of skin cancer, with a cure rate of up to 99% for basal cell carcinoma, the most common type of skin cancer, and for squamous cell carcinoma. ... // Sun protective clothing is clothing specifically designed for sun protection and is produced from a fabric rated for its level of ultraviolet (UV) protection. ...

References

• American Cancer Society: Cancer Facts and Figures-1999. Atlanta, Ga: American Cancer Society, 1999.