• „Most common skin cancer arising from the
basal layer of epidermis and its appendages
• „ Low metastatic potential
• „ Locally invasive, aggressive, and destructive
to skin and bone
• „ Skin cancer: approx. 1.5 million cases per year
• „ BCC is most common skin cancer 80% is BCC
• „ White >> Black
• „ Men >> women
• „ BCC increase with age
• „ Aged 55--70 has 100 fold higher
• incidence of BCC than age 20 and younger
• „ Striking geographic variation
• „ Higher incidence closer to the
• „ *Australia is 40X that of Finland 80%
• Clinical presentation
• A round, nodular, pearly tumour is present
on the left cheek.
• The presence of dilated, sub epidermal blood
vessels (telangiectasia's) is characteristic of
basal cell carcinomas.
• Macroscopic examination of the slide shows a
section of skin and underlying subcutaneous
• Immediately beneath and elevating the
epidermis is a blue cellular tumour composed
of multiple variable sized islands of basophilic
• . The margins of the tumour appear smooth
• Microscope shows nodular masses of tumour cells
(1) extending from the epidermis into the underlying
dermal connective tissue and elevating the overlying
focally ulcerated epidermis.
• The tumour cells have a fairly uniform monotonous
appearance - they are spindle in shape with indistinct
eosinophilic cytoplasm and oval basophilic nuclei with
indistinct nucleoli (2).
• A characteristic feature of basal cell carcinoma is the
tendency of the cells at the periphery of the tumour nests
to become vertically orientated (2) and form a palisaded
Frequent mitotic figures are seen and this is also a feature
of basal cell carcinoma.
• Basal cell carcinomas are believed to arise from
a pluripotential cell in the basal layer of the
epidermis which has the capacity to
differentiate into epidermis and any of its
• Thus in basal cell carcinomas one may see
evidence of keratinisation, hair follicle
formation, or sebaceous differentiation.
• These tumours tend to locally infiltrate and
ulcerate but rarely metastasise.