2. Largest organ of the body (15% of body weight)Largest organ of the body (15% of body weight)
Two main layersTwo main layers
– epidermisepidermis
stratified squamous epitheliumstratified squamous epithelium
contains 5 layerscontains 5 layers
– dermisdermis
connective tissue layerconnective tissue layer
Rests on subcutaneous layer or hypodermisRests on subcutaneous layer or hypodermis
Normal thickness of 1-2 mm, up to 6 mmNormal thickness of 1-2 mm, up to 6 mm
– thicker skin (palms & soles) has stratum lucidum, no hairthicker skin (palms & soles) has stratum lucidum, no hair
follicles or sebaceous glandsfollicles or sebaceous glands
3. Types of CancerTypes of Cancer
Melanoma-forms in melanocytes (skinMelanoma-forms in melanocytes (skin
cells that make pigment).cells that make pigment).
Basal Cell Carcinoma-forms in basal cellsBasal Cell Carcinoma-forms in basal cells
(small, round cells in the base of the outer(small, round cells in the base of the outer
layer of skin).layer of skin).
Squamous cell carcinoma-forms inSquamous cell carcinoma-forms in
squamous cells (cells that form thesquamous cells (cells that form the
surface of the skin).surface of the skin).
4. Neuroendocrine carcinoma-forms inNeuroendocrine carcinoma-forms in
neuroendocrine cells (cells that releaseneuroendocrine cells (cells that release
hormones in response to signals from thehormones in response to signals from the
nervous system).nervous system).
Melanoma is the most serious type ofMelanoma is the most serious type of
cancer of the skin.cancer of the skin.
Basal and Squamous cell cancer are theBasal and Squamous cell cancer are the
two most common types of skin cancer.two most common types of skin cancer.
5. Basal cell carcinomaBasal cell carcinoma
Affects fair skinned adults(>40y) who haveAffects fair skinned adults(>40y) who have
had a lot of sun exposure or repeatedhad a lot of sun exposure or repeated
episodes of sunburn(male>female)episodes of sunburn(male>female)
No Metastasis but BCCs can causeNo Metastasis but BCCs can cause
destructive changes in surroundingdestructive changes in surrounding
tissuestissues
Locally malignantLocally malignant
6. Basal cell carcinoma-types:Basal cell carcinoma-types:
Nodular BCC-most common typeNodular BCC-most common type
Superficial BCC-commonSuperficial BCC-common
Ulcerative (rodent ulcer)Ulcerative (rodent ulcer)
Pigmented BCC- can resemble melanomaPigmented BCC- can resemble melanoma
Turban BCCTurban BCC
Basisquamous BCC-mixed BCC/SCCBasisquamous BCC-mixed BCC/SCC
15. Actinic keratosisActinic keratosis
Rough ,scaly spots on sun-damaged skinRough ,scaly spots on sun-damaged skin
Represent abnormal skin developmentRepresent abnormal skin development
due to exposure to UV radiationdue to exposure to UV radiation
Should be considered potentiallyShould be considered potentially
precancerous(>10 AKs = 10-15% riskprecancerous(>10 AKs = 10-15% risk
SCC)SCC)
Common on exposed sites eg backs ofCommon on exposed sites eg backs of
hands,face,scalp and ears of bald menhands,face,scalp and ears of bald men
17. Bowen’s diseaseBowen’s disease
Bowen’s disease is intraepidermalBowen’s disease is intraepidermal
squamous cell carcinomasquamous cell carcinoma
It is effectively carcinoma-in situIt is effectively carcinoma-in situ
It may progress into squamous cellIt may progress into squamous cell
carcinoma (approximately 5%)carcinoma (approximately 5%)
Because of this, it is very important to treatBecause of this, it is very important to treat
it effectivelyit effectively
18. Bowen’s diseaseBowen’s disease
Presents as a pink or red ,irregular scalyPresents as a pink or red ,irregular scaly
patchpatch
Usually develops in a sun –exposed areaUsually develops in a sun –exposed area
of skinof skin
Common sites include hands and face inCommon sites include hands and face in
both sexes, scalp in men, lower legs inboth sexes, scalp in men, lower legs in
womenwomen
Diagnosis should be confirmed by biopsyDiagnosis should be confirmed by biopsy
21. Squamous cell carcinomaSquamous cell carcinoma
SCC is a common type of skin cancerSCC is a common type of skin cancer
It develops in the epidermis fromIt develops in the epidermis from
squamous cells which produce keratinsquamous cells which produce keratin
Usual presentation is a slowly –growingUsual presentation is a slowly –growing
Can present as a non-healing sore orCan present as a non-healing sore or
ulcer “punched out” in appearanceulcer “punched out” in appearance
Sometimes growth is rapid over a matterSometimes growth is rapid over a matter
of weeksof weeks
23. Squamous cell carcinoma-causes:Squamous cell carcinoma-causes:
UV radiation-damages DNA in skinUV radiation-damages DNA in skin
SCC may develop in an actinic keratosis or patch ofSCC may develop in an actinic keratosis or patch of
Bowen’s diseaseBowen’s disease
Genetic predisposition to develop SCCsGenetic predisposition to develop SCCs
Smoking-especially SCC lipSmoking-especially SCC lip
Thermal burnsThermal burns
Chronic leg ulcersChronic leg ulcers
Immunosuppression-Azathioprine/Ciclosporin.Immunosuppression-Azathioprine/Ciclosporin.
Organ transplantation patients highly susceptibleOrgan transplantation patients highly susceptible
Pre-existing skin conditions eg lichen sclerosus andPre-existing skin conditions eg lichen sclerosus and
lichen planus can predispose to development of genitallichen planus can predispose to development of genital
and oral SCCsand oral SCCs
25. Squamous cell carcinoma-Squamous cell carcinoma-
treatmenttreatment
Excision with 2cm safety margin +_ blockExcision with 2cm safety margin +_ block
dissectiondissection
Radiotherapy may be neededRadiotherapy may be needed
26. Malignant melanomaMalignant melanoma
Melanocytes are found in the basal layersMelanocytes are found in the basal layers
of the epitheliumof the epithelium
Non-cancerous growth of melanocytesNon-cancerous growth of melanocytes
results in moles or frecklesresults in moles or freckles
Cancerous growth of melanocytes resultsCancerous growth of melanocytes results
in malignant melanomain malignant melanoma
27. Malignant melanoma-risk factors:Malignant melanoma-risk factors:
Sun exposure, particularly duringSun exposure, particularly during
childhoodchildhood
Fair skin which burns easilyFair skin which burns easily
Blistering sunburn, especially when youngBlistering sunburn, especially when young
Previous melanomaPrevious melanoma
Family history of melanomaFamily history of melanoma
Previous non-melanoma skin cancerPrevious non-melanoma skin cancer
Large numbers of moles/ dysplastic molesLarge numbers of moles/ dysplastic moles
28. Common sites for melanoma:Common sites for melanoma:
In men commonest site is the backIn men commonest site is the back
In women commonest site is the legIn women commonest site is the leg
Can occur on mucous membranes, eg lipsCan occur on mucous membranes, eg lips
or genitalsor genitals
Can occur under the nailCan occur under the nail
Can occur in eye or mouthCan occur in eye or mouth
BEWARE AMELANOTIC MELANOMABEWARE AMELANOTIC MELANOMA
29. The ABCDE of melanomaThe ABCDE of melanoma
A AsymmetryA Asymmetry
B Border irregularityB Border irregularity
C Colour variationC Colour variation
D Diameter over 6mmD Diameter over 6mm
E Evolving (enlarging or changing)E Evolving (enlarging or changing)
31. When benign melanoma turn malignant, there are:
•Rapid growth (in size, thickness).
•Melanotic nodules around (satellite nodules).
•Induration.
•Metastasis in lymph nodes.
Development of tingling, itching, ulceration and bleeding
35. Growth of melanomasGrowth of melanomas
Horizontal growth withinHorizontal growth within
epidermis=melanoma in situepidermis=melanoma in situ
Vertical growth through basementVertical growth through basement
membrane into dermis=invasivemembrane into dermis=invasive
melanomamelanoma
Once melanoma penetrates dermis,itOnce melanoma penetrates dermis,it
spreads via lymphatic and blood streamspreads via lymphatic and blood stream
= metastatic melanoma= metastatic melanoma
37. Histological classification:Histological classification:
Breslow thickness:Breslow thickness:
This is the thickness of the melanoma in mmThis is the thickness of the melanoma in mm
Clark’s level:Clark’s level:
This describes which layer of skin has beenThis describes which layer of skin has been
breachedbreached
Clark’s level 1-epidermis-melanoma in situClark’s level 1-epidermis-melanoma in situ
Clark’s level 2-dermal invasionClark’s level 2-dermal invasion
Clark’s level 5- invasion of subcutaneous fatClark’s level 5- invasion of subcutaneous fat
38. Treatment of melanomaTreatment of melanoma
Surgical excision with safety marginSurgical excision with safety margin
Thicker melanomas> wider excision +/-Thicker melanomas> wider excision +/-
sentinel node biopsysentinel node biopsy
Regional chemotherapyRegional chemotherapy
39. Prognosis of melanomaPrognosis of melanoma
Breslow thickness< 1mm, almost 100%Breslow thickness< 1mm, almost 100%
5 year survival5 year survival
Breslow thickness > 4mm, only 50%Breslow thickness > 4mm, only 50%
5 year survival5 year survival
Remember, melanoma is a major cause ofRemember, melanoma is a major cause of
death from malignancy in young peopledeath from malignancy in young people