Skin+-+Basal+Cell

The estimated lifetime risk of developing a basal cell carcinoma in the white population is 33-39% in men and 23-28% in women. The incidence of basal cell carcinoma doubles every 25 years. 2 || -Exposure to sunlight: risk is associated with the amount and the nature of accumulated sun exposure over a lifetime, especially during childhood. UVB, 290-320 nm, which causes sunburn, is believed to play a greated role in the development of basal cell carcinoma than UVA -Gene mutations: recent studies demonstrate a high incidence of p53 gene mutations in basal cell carcinoma -Exposure to artificial ultraviolet light (e.g. tannning booths, ultraviolet light therapy). -Ionizing radiation exposure (e.g. x-ray therapy for acne). -Arsenic exposure through ingestion -Immunosuppression -Xeroderma pigmentosum -Nevoid basal cell carcinoma syndrome (basal cell nevus syndrome, Gorlin syndrome) -Bazex syndrome -Personal and family history of previous nonmelanoma skin cancer -Skin type (including albinism) 2 || -Patients often report a slowly enlarging lesion that does not heal and that bleeds when traumatized. -As tumors most commonly occur on the face, patients often give a history of an acne bump that occasionally bleeds. -People who sunburn are more likely to develop skin cancer than those who do not, however sunlight damages the skin with or without sunburn. Consider basal cell carcinoma in any patient with a history of a sore or skin anomaly that does not heal within 3-4 weeks and occurs on sun-exposed skin, especially if it is dimpled in the middle. These tumors may take many months or years to reach even 1 cm in diameter. -Patients often have a history of chronic sun exposure e.g. recreational exposure(sunbathing, outdoor sports, fishing, boating) or occupational exposure (farming, construction). -Occasionally, patients have a history of exposure to ionizing radiation. X-ray therapy for acne was commonly used until 1950. -Occasionally, patients have a history of arsenic intake; arsenic is found in well water in some parts of the United States. -Basal cell carcinoma occurs mostly on the face, head (scalp included), neck, and hands. It rarely develops on the palms and soles. -Basal cell carcinoma usually appears as a flat, firm, pale area that is small, raised, pink or red, translucent, shiny and waxy, and the area may bleed following minor injury. -Basal cell carcinomas may have one or more visible and irregular blood vessels, an ulcerative area in the center that is often pigmented, and black-blue or brown areas. -Large basal cell carcinomas may have oozing or crusted areas. -The lesion grow slowly; is not painful and does not inch.
 * Epidemiology: || Skin cancers account for nearly 1/3 of all cancers diagnosed in the United States each year. Approximately 800,000 new cases are diagnosed each year. 1 
 * Etiology: || The exact cause of basal cell carcinoma is unknown. Environmental and genetic factors that are believed to predispose patients to basal cell carcinoma skin cancer include the following:
 * Signs & Symptoms: || -Basal cell skin cancer tumors typically appear on sun-exposed skin.

Clinical presentation of basal cell carcinoma varies by type: -__Nodular basal cell carcinoma__ - the most common type; usually presents as a round, pearly, flesh-colored papule with telangiectases. As it enlarges, it frequently ulcerates centrally leaving a raised, pearly border with telangiectases; most tumors are observed on the face, although the trunk and extremities also are affected. -__Cystic basal cell carcinoma__ - an uncommon variant of nodular basal cell carcinoma; cystic basal cell carcinoma is often indistinguishable from nodular basal cell carcinoma clinically, although it might have a polypoid appearance; typicallly, a bluish-gray cyst-like lesion is observed; the cyst center of these tumors is filled with clear mucin that has a gelatin-like consistency. -__Pigmented basal cell carcinoma__ - another uncommon variant of nodular basab cell carcinoma that has brown-black macules in some or all areas, often making it difficult to differentiate from melanoma; typically some areas of these tumors do not retain pigment; pearly, raised borders with telangiectases that are typical of a nodular basal cell carcinoma can be observed; this aids clinically in differentiating this tumor from a melanoma. -__Morpheaform (sclerosing) basal cell carcinoma__ - an uncommon variant in which tumor cells induce a proliferation of fibroblasts within the dermis and an increased collagen deposition (sclerosis) that clinically resembles a scar; the tumor appears as a white or yellow, waxy, sclerotic plaque that rarely ulcerates; the morpheaform subtype is the most difficult subtype to diagnose; because the tumor infiltrates in thin strands between collagen fibers, treatment is difficult to distinguish; Mohs micrographic surgery is the treatment of choice for this type of basal cell carcinoma. -__Superficial basal cell carcinoma__ - is often multiple, most often developed on the upper trunk or shoulders; it grows slowly and appears clinically as an erythematous, well-circumscribed patch or plaque, often with a whitish scale; occasionally minute eschars may appear within the patch or plaque; the tumor appears multicentric with areas of clinically normal skin intervening among clinically involved areas. 2 || -Physical examination should focus on appreciation of changes in the normal appearance of the skin. -The size, diameter, depth of invasion and mulitfocality of the tumor must be precisely defined. -Regional lymph nodes must be assessed. -Various tools to assess the skin, including Wood's light and potassium hydroxide preparations, fungal cultures, skin biopsies, Tzanck smears and patch testing should be used. 1 || Grading for Basal Cell. 3 || Carcinoma of the Skin. 4 || || **References** 1. Chao KS, Perez CA, Brady LW. //Radiation Oncology - Management Decisions. //  2nd ed. Philadelphia: Lippincott, Williams & Wilkins, 2002: 111-122. 2. eMedicine. Basel Cell Carcinoma. []. Accessed February 11, 2010. 3. Gunderson and Tepper. Clinical Radiation Oncology. 2nd Edition. Philadelphia, PA: Churchill Livingstone. 2007. 4. Cox. Radiation Oncology; //Rationale, Technique, Results//. 8th Edition. St. Louis, MO: Mosby. 2003. 5. National Library of Medicine. []. Accessed February 21, 2010. 6. Treatment photos courtesy of Sheri Griffin. Good Samaritan Regional Cancer Center. Corvallis, OR.
 * Diagnostic Procedures: || -The diagnosis of skin cancer requires a detailed clinical history.
 * Histology: || Nodular basal cell carcinoma, Cystic basal cell carcinoma,-Pigmented basal cell carcinoma, Morpheaform (sclerosing) basal cell carcinoma,Superficial basal cell carcinoma 2 ||
 * Lymph Node Drainage: || Basal cell carcinomas can spread to lymph nodes. 2 The location of lymph nodes involved depends on the location of the original diagnosis. ||
 * Metastatic Spread: || Basal cell carcinomas rarely metastasize. The incidences of metastases is less tha 0.1%. The common sites of metastatic spread are lymph nodes, lungs and bones. <span style="color: #008000; font-family: Arial,Helvetica,sans-serif; font-size: 80%; vertical-align: super;">2 ||
 * Grading: || [[image:grading1.jpg width="145" height="88"]]
 * Staging: || [[image:carcinomaofskin1.jpg width="205" height="294"]]
 * Radiation Side Effects: || Side effects may include erythema, skin irritation, dry desquamation, and moist desquamation. 5 ||
 * Prognosis: || The prognosis of these patients is excellent. The rate of basal cell skin cancer returning is about 1% with Mohs surgery, and up to 10% for other forms of treatment. Smaller basal cell carcinomas are less likely to come back than larger ones. 5 ||
 * Treatments: || Surgery for lesions smaller than 2cm. For areas that are larger or in cosmetic areas Radiation Therapy is best. A 2cm margin is required. Treated to 2 to 5 Gy in 6 to 20 fractions. 1 ||
 * TD5/5: || The TD5/5 for skin is 15-30Gy in a single dose and 30-40Gy with fractionation. 1 ||
 * Planning Photos || Basal cell carcinoma of the ear. Treated with 6 MeV electrons to a dose of 5000cGy at 250cGy per fraction for 20 fractions. 6