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Skin carcinomas

Carcinomes cutanés 1
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Introduction /Classification:

Epithelial cancers: keratinocyte deriver, epithelioma or carcinomas: basal and spinocellular carcinoma

Non-epithelial cancers: drifts from other cells: melanoma (melanocyte), sarcoma (fibroblast)


Exogenous agents: cause alterations in cellular DNA, resulting in a mutation leading to a cancer cell: ultraviolet aorlysic rays A or B, ionizing radiation or oncogenic viruses

Chemical agent: aromatic polycyclic hydrocarbons, pesticides

Genes responsible for cell transformation: abnormal, only in tumor cells, precise carcinogenic factors, ultraviolet rays

Genes that confer a genetic predisposition to cancer: genodermatosis that exposes the risk of developing skin tumours, mainly Xeroderma pigmentosum, mutations are carried by all cells of the body. Early age

Tumor suppressing genes (P53 gene): controls the smooth running of the cell cycle, it is a true guardian of the genome, stopping the cell cycle after genotoxic stress (UV), which allows to repair the genomic damage suffered before continuing mitoses

Basal cell carcinoma



Sun: major carcinogen, repeated sun exposure (holidays, sports activity) – prevention and school education measures

Genetic predisposition: are more common in light-skinned subjects, phototype I/II

MC1R: gene involved in skin pigmentation (photo-protective melanin), certain variants are risk factors for skin cancer

Geno-dermatoses predispose to basal cell carcinomas: Xeroderma pigmentosum

Immunodepression: Organ transplants cause more basal cell carcinomas, HIV

Clinical aspects:

Seat: photo-exposed areas, in 80% of cases: head, neck, face

Nodular shape: the elemental lesion may remain unique and increase in size giving a pink-coloured nodule traversed by fine telangiectasies, the most common form

Scar plane: the elemental lesion multiplies, several epitheliomama beads will match in rosary and take a rounded layout: smooth atrophic center and elevated periphery by the juxtaposition of pearls

tattooed basal cell carcinoma: the elementary lesion will pigment, brown spots, covering the surface of the tumor – nodular melanoma

Sclerodermiform shape: whitish, hard and shiny imprecise boundaries, the surface is depressed and retractable, covered with telangiectasies. Recidivism

Ulcerated shape (ulcus rodens): nail-stroke ulceration, slowly extended, with beaded border

Waxing form: digging ulceration with a large necrotic crater that can lead to severe mutilation


Clinical: in front of the fixedness of the lesions, the beaded border and the presence of telangiectasies

Histology: a proliferation of small, clear-limit basaloid cells reminiscent of epidermal basal layer cells. These cells cluster in compact cell clusters and take on a palisadic peripheral arrangement.  The tumour remains well delineated compared to the rest of the dermis

Evolution / Prognosis:

Ulcerated form: destruction of tissue under the skin, cartilage tissue or underlying bone tissue creating a gateway to overinfection germs and complicating itself with naso-sinus infection or septic meningitis causing mortality



Uses effective photoprotection:

Spinocellular carcinoma



Etiological factors (precancerous lesions)

Actinic Keratosis: Frequent lesion on photo-exposed areas: face, extremities, scalp. Elderly, fair skin, erythematous lesion, brownish, rough

Radio-induced Keratosis

Keratosis of aromatic polycyclic hydrocarbons: incomplete combustion of wood, coal or oil (refining products, fuels, tar…)

Skin scars: burns, radiodermites – regular monitoring

Chronic sores: chronic leg ulcers – risk of degeneration


Chronic Actinic Cheilitis: professionals exposed to the sun: atrophy, erosion, dander, lower lip

Smoking Cheilitis: smoker, keratosic plaque, whitish

Anogenital mucous membrane:

Infectious Origin:

HPV: oncogenic types, Bowen's disease, carcinoma in situ

Mucous Dermatosis:

Sclerotic lichen: chronic dermatosis, pruritus, vulva, whitish lesion, sclerosis


Ulcero-vegetative shape: more frequent, protruding and infiltrating tumour, irregular surface, seat of a budding and bleeding ulceration, undeed edges

Clinical forms:

The tumour combines the different semiological elements in varying proportions:

Positive diagnosis:

Clinic – histology

Evolution / Prognosis:


In case of topography at aesthetic and/or functional risk cryosurgery, radiotherapy, laser…

In case of metastases: surgery, palliative treatments


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