Basal Cell Carcinoma | Simple Revision Notes for Medical Students

UV light exposure is thought to be the major aetiological cause, particularly exposure in childhood. Tanning/using sun beds
Fair skin/blue eyes/blond hair
Immunosuppression
Inherited syndromes
Gorlin syndrome is a rare condition which increases the risk of basal cell cancer, as well as other tumours such as medulloblastomas.

Can be shiny or pearly
Presents usually as plaque or nodule
May also present as non-healing wounds or scabs
Visible telangiectasia on the surface
Do not produce keratin so they can appear quite translucent. They can, however, be pigmented, especially in patients with darker skin
Umbilicated centre
Tend to occur in sun exposed areas e.g. face, ears, neck, chest etc.
If left untreated, the BCC can ulcerate and increase in size. In this scenario, they typically form a rolled, pearly edge with a crater in the middle.

Kelly Nelson, M.D., (Photographer), CC0, via Wikimedia Commons

Superficial Basal Cell Carcinoma

No machine-readable author provided. John Hendrix assumed (based on copyright claims)., Public domain, via Wikimedia Commons

Nodular Basal Cell Carcinoma

There are many different sub-types of BCC:

Nodular: The most common type of facial BCC, whereby individuals have a pearly, smooth nodule.
Superficial: These present as plaques and may have scales
Morephoeic: These are usually in the mid-facial area and tend to have a waxy surface. They are able to infiltrate cutaneous nerves (perineural invasion).
Basosquamous: These are a mix of BCC and squamous cell carcinomas and tend to be more aggressive.

The mainstay of investigation is to biopsy the lesion and histologically confirm presence of BCC.

Excision Biopsy: Surgical excision is the recommended treatment with usually 3-5mm tumour margin, although this margin can increase for larger BCCs.
Mohs Micrographic Surgery: This is where a lesion is excised layer-by-layer, and each layer is examined microscopically. Excision continues until tumour is no longer visible on microscopy. This can be useful for sites where you are trying to conserve as much tissue as possible e.g. facial lesions.
Topical creams
- Imiquimoid: This is an immunomodulator that can be used for superficial BCCs
- Fluorouracil cream (5-FU): This is a cytotoxic drug which again, can be used for superficial lesions
In patients that do have advanced or metastatic BCC, Hedgehog pathway inhibitors such as vismodegib can be used.
Radiotherapy: Patients who are unsuitable for excision/Mohs may be offered radiotherapy.

Dermatology Revision Notes