Dermatology skin blog: Skin Biopsy
When is a skin biopsy required?
Malignant Melanoma in a previous mole
If a mole
- has changed in its appearance,
- is asymmetrical,
- has an irregular border,
- has a varied colour
- is growing,
- or if a new skin lesion is growing or bleeding,
we must suspect a skin cancer.
Once we suspect a skin cancer, a biopsy is required. In this blog post, I describe what happens when Dr Jennifer Crawley, the Consultant Dermatologist suspects a skin cancer.
How does a skin biopsy for a skin tumour work
At Clinica London, Dr Jennifer Crawley runs a dermatological service for non-melanotic skin cancer and melanoma. Melanoma is also known as malignant melanoma, which is self-evident. She will see the patient at a consultation, examine the body for moles and other lesions and then carry out dermoscopy of suspected lesions.
If there is enough suspicion in terms of asymmetry, beveling of the edge, change of colour or contour, and increasing darkness of a lesion, she will then carry out a biopsy. See my next skin blog for more about the A, B, C, D and E method of detecting malignant melanoma.
If the biopsy is for a non-melanotic skin cancer, meaning one that is not pigmented, then an incisional biopsy can be done where a very small amount of tissue is taken off with a punch for histopathological analysis. Usually, the edge of the suspected tumour is taken along with some normal skin and we send that in saline preservative solution to the laboratory, with the results back within one week.
Jennifer likes to see patients herself to talk them about the results of a biopsy because if it is going to be cancer it is something that needs to be discussed in person, rather than a lab report just sent to the patient.
If she suspects a malignant melanoma or the differential diagnosis is melanoma, when the mole is pigmented, then she will do en bloc excision. She explains to the patient that she has to take a slightly larger amount of normal tissue around the whole region
and some normal tissue deep to it, in order to remove it entirely. This may involve putting in some stitches and removing those stitches (sutures) about a week later, by which time the histopathology result is available.
She will insist on seeing the patient back at Clinica London for removal of the stitches herself or by the nurse and for discussion of the histopathology result with herself.
What recommendations might we give to a patient with skin cancer?
If the patient has a skin cancer, they require appropriate further treatment, which could be Mohs micrographic surgery for a basal cell carcinoma or squamous cell carcinoma, or a wider Mohs excision for melanoma if a residual tumour has been found, plus mapping and detection of lymph node involvement. She will counsel the patient on what the best treatment is and arrange that treatment either to be done by herself, or by a specialist unit; for instance a Mohs micrographic surgery unit.
If the patient has one skin cancer, they are at risk of getting another one. I always say to patients, if you have had one basal cell carcinoma, you are almost undoubtedly going to get another one within the next 10 years. This is not based on science, other than common sense that the skin that has been exposed to the sun already has shown to have a weakness for the development of non-melanotic skin cancer. Often, there are many sun damaged patches of skin which are clearly not tumours at present, but which may transform into pre-malignant lesions and finally malignancy.
If you have any doubts about lesions on your skin that you think may be a little pearly basal cell carcinoma, or a more ulcerated looking squamous cell carcinoma, or a darker looking malignant melanoma, or a mole that you have had for a time that is changing or a new mole, then you should see Consultant Dermatologist, Dr Jennifer Crawley.
Dr Crawley is a consultant at University College London. She is a dermatologist and she specialises in skin tumours AND inflammatory skin diseases, eczema, psoriasis and keloid scar treatment. Between 25% – 30% of her patients seen at Clinica London have suspected skin cancers. Fortunately, many of them turn out to have benign lesions, but equally many do not, and go onto have further treatments which can be further excision either by herself or the Mohs micrographic surgeon.
Jennifer Crawley is the Consultant Dermatologist at Clinica London with a special interest in dermatology. She is an expert in both adult and paediatric dermatology and has particular interests in research, teaching and leading audit projects.