Skin Cancer Flashcards
Spread of melanoma
Local spread
- lesion expands horizontally at basal lamina
- dermal invasion of lesion - metastatic potential
Lymphatic
Haematogenous
Risk factors for melanoma
UV radiation - sun exposure and sunburns - naturally light skin - exposure early in life Nevi - benign growths Genetic background - xeroderma pigmentosum - Werner syndrome PMHx of melanoma Immunosuppression
Pathophysiology of melanoma
Malignant tumour that starts in melanocytes (melanin-producing cells)
Often starts as slow-growing superficial tumour
Features of melanoma on examination
A - asymmetry B - border irregularities C - colour variegation (different colours in same region) D - diameter greater than 6 mm E - evolving
Ix for melanoma
Dermoscopy Biopsy USS to check lymph nodes CXR CT/MRI/PET
Mx of melanoma
Wide local excision +/- sentinel lymph node biopsy Surgical resection Lymph node dissection Biological therapies - nivolumab Radiotherapy
Features of basal cell carcinoma on examination
Nodular
- pink, pearly, well demarcated lesion with telangiectatic vessels
- bleeding
Superficial
- erythematous, well-defined, scaly/shiny lesion
- pruritius
Sclerosing
- pale colour with poorly defined borders
Most common over head and neck
Features of squamous cell carcinoma
Overlying scale
Erythematous
Well-defined borders
Mx of non-melanoma carcinoma
Surgical excision Moh's surgery - microscopic margin control Radiation therapy Curettage and electrodessication Cryotherapy Topical 5-FU Imiquimod
Premalignant conditions for non-melanoma
Actinic keratosis
- erythematous and scaly
Bowens disease
Nice major criteria for skin lesion
2 points each
Change in size
Irregular shape
Irregular colour
Nice minor criteria for skin lesion
1 point each Largest diameter 6mm or more Inflammation Oozing/bleeding Change in sensation
Nice criteria for skin lesions
3 points = secondary care skin cancer clinic within 2 weeks
Types of ix for skin lesions
Shave biopsy
Punch biopsy
Excision biopsy - whole lesion removed
Incisional biopsy - part of lesion and part of healthy skin removed
Key points of incisional biopsy
See border
Don’t have to remove whole lesion
Skin biopsy considerations
Does it look worrying - need to take out whole lesion
Location - cannot remove whole lesion
Patient
Histology of squamous cell carcinoma
Atypical polygonal cells with abundant cytoplasm
Keratin formation
Prominent intercellular bridges
Histology of basal cell carcinoma
Discrete nest of dark blue cells
Attached to epidermis
Peripheral palisading
Retraction artefact
Hisology of malignant melanoma
Abundant melanin pigment in cells - brown
Light pink staining cytoplasm
Prominent nucleoli
Small nests of atypical cells
Define basal cell carcinoma
Slow-growing locally invasive malignant tumour of the epidermal keratinocytes
Normally in older individuals
Mx of basal cell carcinoma
Surgical excision - treatment of choice as allows histological examination of tumour and margins
Mohs micrographic surgery - excision of lesion and tissue borders progressively excised until specimens microscopically free of tumour
Radiotherapy - when surgery not appropriate
Cryotherapy
Curettage and cautery
Topical photodynamic therapy
Topical treatment - Imiquimod
Describe squamous cell carcinoma
Locally invade malignant tumour of the epidermal keratinocytes or appendages
Potential to metastesise
Presentation of squamous cell carcinoma
Keratotic, ill-defined nodule which may ulcerate
Mx of squamous cell carcinoma
Surgical excision - treatment of choice
Mohs micrographic surgery
Radiotherapy - large non-resectable tumours
