Basal Cell Carcinoma.

BCC is the most common type of skin cancer.

What is a BCC?

A BCC (Basal Cell Carcinoma) is the most common type of skin cancer. Hugh Jackman did us all a favour by tweeting that he’s had a couple removed. BCC is a very common finding at a skin cancer clinic. The cancerous cells originate from the most bottom layer of the epidermis.

BCC is slow growing and only very rarely spreads elsewhere. On the other hand, SCC and melanoma can be very serious. So why is it still good to get a diagnosis of BCC earlier than later? There are two main reasons.

Firstly, a superficial BCC may be treated with cream if it’s still superficial at the time of diagnosis.

Secondly, the length of the scar required to cut out a nodular BCC will be longer than you’d expect. To illustrate this point with precise figures, a 4mm BCC will be cut out with a scar length of 24mm, and a 6mm BCC will have a scar length of 30mm. In other words, for every 1 mm of growth of a BCC the scar will be 3mm longer. This is clearly a problem on the face but also in areas that don’t heal so well such as the lower legs. Bear in mind that these figures are conservative. Some types of BCC will need a wider excision.

BCC does very rarely spread to other areas of the body. There is a new immunological agent (Vismodegib)  that can be used for metastatic BCC.

All this means that a small BCC may need to be cut out with much wider margins that you think.

What puts people at risk of BCC?

BCC is very common in Australia of course with UV light the major risk factor for BCC (primarily UVB). It’s thought that intermittent intense exposure to sunlight is especially important although so is long term cumulative sun exposure (though the latter is not as important a risk factor as that for squamous cell carcinoma). Use of tanning machines increases risk around 1.5 fold.

Genes are also very important in the development of BCC and there is increasing work in this area (eg p53 tumor suppressor gene).

Other common risk factors are prior radiotherapy and immunosuppression (though less important than with SCC). Rare risk factors are arsenic exposure and some hereditary conditions such as nevoid basal cell carcinoma syndrome.

The clinical types of BCC

There are different types of BCC requiring different treatments. The broad category of BCC may be established clinically prior to excision. However, the pathology report is required to identify any concerning features and to confirm the BCC subtype.

Let’s describe the two main types of BCC:

  • Nodular BCC that is raised, shiny, may be pigmented & usually occurs on the face. Nodular BCC needs to be cut out.
  • Superficial BCC that is flat, pink, & usually occurs on the trunk or limbs. This may be treated with skin cancer cream.

Now let’s look at all the main types of BCC in more detail.

Superficial BCC

Superficial BCC accounts for around 30% of Basal Cell Carcinoma. The condition tends to occur in a younger age group than those affected by other BCC types. UV light is a little less important in the development of superficial BCC than nodular BCC.

Superficial BCC appears as a pink or red flat lesion with well defined borders. On stretching the skin, there may be a slightly raised edge though this is a subtle sign. When you know what to look for, the edge may be slightly pearly in appearance. The lesion itself may be slightly shiny and/or  scaly. These signs are not very specific, and a superficial BCC may look similar to an IEC (Bowens disease). A dermatoscope will certainly help distinguish the two.

Superficial BCC may be treated non-surgically. The most common non-surgical treatment is with Imiquimod (®Aldara) cream.

superficial BCC 2

superficial BCC – note how spreading the skin is the best way to see the colours and texture. (Image reproduced with permission from PCDS.org.uk)

superficial BCC - typical

This superficial BCC is really typical – the red colour has a bluish tinge to it and there are some small ulcers within the lesion.

Nodular BCC

Nodular BCC is the most common type of BCC, accounting for around 60% of all Basal Cell Carcinoma. UV light is the key risk factor.  This type of BCC is found most commonly on the face, head and neck.

A nodular BCC is a raised lesion. Like all BCC, stretching the skin around it may make the pearly colour more obvious. The colour of the lesion itself is pink or red. There may be a central ulcer (the so-called “rodent ulcer”) or a central crust. Look for fine blood vessels coursing over the top of it in the shape of a branch (“Arborising Vessels” – much better seen with a dermatoscope). The lesion tends to bleed with minor trauma and may be a little itchy.

Nodular BCC right cheek

nodular BCC right cheek – it’s pink and a close look may show fine blood vessels & a pearly border. (Image reproduced with permission from PCDS.org.uk)


This is behind the ear

This BCC  is behind the ear (courtesy of PCDS.org.uk)

This is a large nodular BCC on the side of the nose (courtesy of PCDS.org.uk)

This is a large nodular BCC on the side of the nose (courtesy of PCDS.org.uk)

Pigmented BCC

A Pigmented BCC is simply that … a BCC with some brown or black areas within it. Typically, a pigmented BCC is not completely pigmented and will have some pink or red area and/or pearly border like a non-pigmented one. They may be reasonably flat or raised like a nodular BCC. The important point about this uncommon type of BCC is that it may look like a melanoma.

Pigmented Basal Cell Carcinoma - they tend to be nodular.
Pigmented BCC – they tend to be nodular (Image reproduced with permission from PCDS.org.uk)
Morphoeic BCC

Morphoeic Basal Cell Carcinoma accounts for 5 to 10% of BCC. The lesion is hard to spot because doesn’t look like a normal BCC! It is scar-like (hence the term morphoea). Typically, it feels hard or firm with an ivory colour, and the borders are poorly defined. When pink,  it may have fine blood vessels and be easier to spot.

A morphoeic BCC tends to spread and has a higher recurrence rate – and so is harder to treat than other types.

Morphoeic BCC
Morphoeic BCC – final diagnosis will require a pathology report. (Image reproduced with permission from PCDS.org.uk)
Morphoeic BCC
Morphoeic BCC – this one would feel firm & there are some fine blood vessels.
Morphoeic BCC above right lip
Morphoeic BCC: also would feel firm & note the pearly colour within it.