Skin cancer

The term “skin cancer” refers to various malignant skin tumours.


The term “skin cancer” refers to various malignant skin tumours. The most dangerous is “black skin cancer”, or melanoma. We will also look at basal cell carcinoma and squamous cell carcinoma. The primary risk factor is UV rays. The body should be regularly examined for skin changes in accordance with the ABCD rule.


Melanoma (black skin cancer)

  • Occurs: mostly in adults, but can occur at any age
  • Location: anywhere on the body, including on the fingers, feet, under the nails, and on mucous membranes
  • Pain, itching, burning, “restless” feeling of the affected skin
  • Sometimes the spots burn, ooze or become inflamed
  • Appears on previously normal skin, sometimes on previously inconspicuous liver spots
  • ABCD rule: “rule of thumb” for detecting skin changes (in particular melanoma)
    • A = Asymmetry: irregular rather than round
    • B = Borders: irregular, restless, smudged, with runners, fringes and tongues
    • C = Colours: changing colours inside the melanoma, with light and dark patches, different shades (black, brown, reddish, grey)
    • D = Diameter: the spot changes in size, colour, shape or thickness (rate of growth)
  • Consequences: even small melanomas can spread at an early stage and form tumours in the lymph nodes and internal organs where metastases are formed

Basal cell carcinoma (basalioma)

  • Occurs: usually after the age of 45
  • Location: 80% in the face, usually above the line that runs from the corner of the mouth to the earlobe
    • I.e. areas of skin that are exposed to the sun; often also on the scalp under the hair
    • More rarely on the hand, forearm or torso
  • Shape, colour:
    • Skin-coloured, greyish white, shiny or reddish nodule
    • Can change colour to brown or yellowish brown
    • Sometimes the growth breaks open, oozes, bleeds and forms a crust
    • Indentation in the centre
  • Diameter: 0.5 to several centimetres
  • Consequences: can grow deep and invade cartilage and bone
    • Can be locally destructive, but seldom forms metastases

Squamous cell carcinoma (prickle cell carcinoma)

  • Occurs: usually after the age of 55; frequency increases with age
  • Location: primarily in the face, in particular in areas that are very exposed to light (“sun decks”) such as the forehead, ears, nose, bottom lip
    • Also in transition zones between skin and mucous membranes
    • Particularly aggressive growth on the lining of the mouth and the tongue (smoking cigarettes)
  • Shape, colour:
    • Initially often looks like a hard lump, callus or scaly eczema
    • Later evolves into a wart-like growth which can turn into an ulcer
    • Often reddish in colour, usually grows slowly
  • Warning sign: wounds or scars that don't heal
    • A lump forms inside the wound
    • All wounds and lumps that don’t heal within four weeks are suspicious
  • Consequences: grows aggressively deep and also spreads widely

Causes and treatment


The precise causes are still unclear, but there are widely confirmed risk factors:

  • Ultraviolet radiation (UV rays; also at solariums)
    • In particular repeated sunburn as a child and adolescent (skin doesn’t “forget” the sunburn, even after many years)
    • Regular visits to a solarium double the risk of developing precursors to skin cancer. Doctors expressly advise against solariums
  • Genetic disposition: indicator of basal cell carcinoma and melanoma
  • Most at risk are:
    • Fair-skinned people (skin types I and II) whose skin doesn't tan
    • People with many pigmented spots (birth marks, liver spots)
  • Immunodeficiency (disease, certain medicines) promotes the development of skin cancer and other malignant tumours
  • Increase in skin cancer
    • Owing to people’s higher life expectancy
    • Western lifestyle with much travel, mountain sports, etc.

Further treatment by your doctor / in hospital

Possible tests
  • Skin examination
  • Skin biopsy
  • Depending on the stage, ultrasound (sonography) and blood test
Possible therapies
  • Cutting out the skin tumour with a scalpel (surgery)
  • Basal cell carcinoma: cryotherapy (freezing), photodynamic therapy and radiation
  • Medication (chemotherapy) for distant metastases
  • Aftercare is very important
    • Recurrences (tumour regrows in the same place)
    • Many patients later develop another malignant skin tumour somewhere else

What can I do myself?

  • Avoid sunburn (very dangerous: beach and mountains)
    • Use sun screen with a sun protection factor of at least 30 and UVA as well as UVB protection
    • Keep to the shade (particularly between 11 am and 3 pm)
    • Wear clothing that provides good skin cover and a wide-brimmed hat
    • Tightly woven, dark or vibrantly coloured clothing and synthetic fibres provide the best protection
  • Sunglasses with 100% UV protection
  • Doctors expressly advise against solariums
  • Regular self-examination to identify skin changes
    • Don’t forget the feet, back and scalp (ask someone else to help)
    • Apply the ABCD rule
  • Children need special protection:
    • Never expose babies younger than one to direct sunlight
    • Until the age of 2, use sunscreen with a high component of micropigments that reflect the sunlight.
    • Don't use products containing allergens, e.g. perfume
    • Special UV-protective clothing
  • Tips for using sunscreen:
    • Apply at least half an hour before going out in the sun (it doesn’t work immediately)
    • Apply generously
    • Re-apply generously after 2 to 3 hours (also re-apply water-resistant products)
    • Sunscreen shouldn’t encourage you to stay in the sun for too long

When to see a doctor?

  • Skin spots that suddenly start itching, oozing or otherwise change
  • Wounds that don’t heal well
  • As a general rule,
    • every lump and wound that doesn’t heal within 4 weeks should be examined
    • Early detection and early treatment are decisive for a positive outcome

Further information

Swiss Cancer League (Schweizerische Krebsliga)

Selbsthilfe Schweiz (Self-Help Support Switzerland)


skin cancer, basalioma, squamous cell carcinoma, basal cell carcinoma, melanoma, prickle cell carcinoma, malignant melanoma, black skin cancer, fair skin cancer

Exclusion of liability

CSS offers no guarantee for the accuracy and completeness of the information. The information published is no substitute for professional advice from a doctor or pharmacist.

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