Non Melanoma Skin Neoplasms Flashcards
What are the different types of non melanoma skin cancers and their precursors?
- Basal Cell Carcinoma
- Squamous Cell Carcinoma
Precursors:
- Actinic Keratosis
- Intraepidermal carcinoma
- Bowens disease
Where do the different non melanoma skin cancers and there precursors arise from?
BCC (basal cell layer of the epidermis)
SCC and precursors (prickle cell layer of the epidermis)
What are the risk factors for developing skin cancers?
- Long term sun/UV exposure
- Immunosupression
- Sites of chronic inflammation (scars and wounds)
- Human Papiloma Virus (SCC)
- Genetic (Gorlim Syndrome BCC, Xeoderma pigmentosa)
- Fair skin
- Age
Describe the characeteristics of BCC (aka how common, prognosis etc)?
- 80% of all skin cancers
- Incidence increases with age
- Very slow growing and usually assymptomatic
- Rarely metastatic but they are locally invasive
What is the characeteristic appearance of a BCC?
- Well defined lesion on a sun exposed area.
- Pearly shiny rolled edges.
- Telangectasia.
- Area of ulceration and crusting.
What are the factors which should be taken into account when assessing the risk factor of recurrence in a BCC?
- Increasing tumour size
- Site (more likely to reoccur if it is on the face)
- Poorly defined margins
- Previous treatment failure
- Histological subtype and behaviour (how invasive it was previously)
Describe the characeteristics of SCC (aka how common, prognosis etc)?
- ~20% of all skin Ca
- Metastatic potential usually spreading to regional lymph nodes
- 5 year survival is 75-90% but only 25% if there are metastases.
Which factors increase the chance of metastasis in SCC?
- SCC on the ear or lip aka any mucosal surface
- Size >2cm
- Poor differentiation
- SCC on a non sun exposed site aka areas of chronic inflammation
How can a SCC present?
- A skin coloured lesion with a keratin plug.
- A soft fleshy nodule with an eroded surface.
- A non healing ulcer.
- Grows over weeks to months.
What is the treatment for BCC and what factors should be considered when choosing a treatment option?
- Simple surgical excision with a margin of 4mm.
- For higher risk cases aka recurrent or in high risk of recurrence ‘Moh’s micrographic surgery’ is used. A greater amount of tissue is removed.
Other methods which can be used are:
- Currette and cautery
- Cryotherapy
Non surgical methods:
- Radiotherapy (not used often as increases risk of SCC)
- Imiquimod (immunotherapy cream)
- Photodynamic therapy
- The non surgical methods have a higher risk of recurrence but better cosmetic appearance. Surgical excision should always be used unless the BCC is deemed to be low risk, if another method is being used which does not allow histological examination post treatment a biopsy needs to be taken to confirm the diagnosis.
What are the treatment choices for SCC?
- Surgical Excision (1st choice usually)
- Moh’s Micrographic Surgery - for ill-defined, large, recurrent tumours
- Radiotherapy - for large non-resectable tumours
What is actinic keratosis?
- It is dysplasic keratotic lesions.
- These are premalignant and have a small risk (1-1000) of turning into SCC.
- They are common in sunexposed sites in the elderly.
What are the different treatment options for actinic keratosis?
- Cryotherapy
- Curation and cautery
- Imiquimod cream
- Efudix cream (5-fluorouracil cream) - takes weeks
- Photodynamic therapy
What are the other names for intraepidermal carcinoma and what is it?
It is dysplasia which extends the full thickness of the epidermis but is not yet invaded the basement membrane. Pre-malignant can become an SCC (3-5%).
Also known as:
- Bowen’s disease
- Intraepithelial carcinoma
- Squamous cell carcinoma in situ
Usually occurs on the lower legs of elderly women.
What are treatment options for intraepidermal carcinoma and what must you consider when choosing a treatment?
- Excision
- Imiquimod
- 5-fluorouracil cream (efudix)
- Photodynamic therapy
- Cryotherapy however as lesions are often on the leg need to consider the risk of leg ulcers. Therefore cryo is usually avoided and photodynamic therapy is a good option in those with venous insufficiency.
What is the following lesion?
Superficial BCC
What is the following lesion?
SCC
Note the eroded surface
What is the following lesion?
Pigmented BCC
Can easily be mistaken for a MM
What is the following lesion?
SCC
Non-healing ulcer
What is the following lesion?
Nodular BCC
What is the following lesion?
SCC
What is the following lesion?
Intraepidermal Carcinoma
AKA bowen’s disease, intraepithelial carcinoma, squmous cell carcinoma in situ
Could be mistaken for eczema or psoriasis
What is the following lesion?
Actinic Keratosis
