Benign intracutaneous and subcutaneous tumours may be considered for excision. General practitioners should not attempt the following operations: excision of ganglions, excision of large lipomas, excision of lateral and medial cervical cysts, excision of breast tumours and operations involving a leg with insufficient circulation. These operations should be performed by a specialist to minimise the risk of complications. If malignancy is suspected (dysplastic naevi), the patient should always be referred to a specialist. From the time of establishing an indication to the performance of an intervention (surgical or otherwise), you should consider factors that influence wound healing. For a patient with poor vascularisation of the feet, the risk of a necrotic toe outweighs the treatment of an ingrown toenail.
Examples of Therapeutic Interventions
Freezing with liquid nitrogen is achieved by applying liquid nitrogen with a cotton swab. This cotton swab is held against the skin eruption until it freezes to depth of 1 mm into unaffected skin. Freezing too deeply or for too long results in scarring and depigmentation.
Excision = Removal by cutting. e.g. sample excision (cutting out a piece of tissue for anatomical-pathological assessment) and excision of the wound margins. The following rules apply to excision:
- Incision lines follow the lines of the skin [Figures 7a, 7b].
- Incision lines for intracutaneous tumours are oval-shaped.
- Incision lines for subcutaneous tumours run across the tumour.
- Each tumour or dermatological defect excised must be submitted for anatomical-pathological assessment.
 Figure 7a |
 Figure 7b |
Excochleation involves scooping or scraping out tissue with a sharp spoon (curette).
Extirpation is resection, eradication. Extirpation is usually considered when an entire organ or tumour must be removed (uterine extirpation or extirpation of a breast tumour).
In discussions of the various therapeutic options for tumours and skin lesions, the treatment of choice is always mentioned first. The techniques involved with these interventions are discussed in the section “Skills.“
Intracutaneous Tumours
Resected specimens must always be submitted for anatomical-pathological assessment.
Keratinous Cyst
Intracutaneous retention cysts, surrounded by a connective tissue capsule and filled with sebum. Examination reveals that the skin is fixed to the tumour and the outlet to the sebaceous gland is often visible under the skin as a black dot. Frequent sites include the pilose scalp, behind the ears, earlobes, neck, back, and groin.
Complications: Tendency towards infection, abscess, and fistula formation.
Reasons for treating: Cosmetic considerations; pain due to local pressure; prevention of infection.
Therapy: Extirpation. If the keratinous cyst has abscessed, incision and drainage followed by extirpation in a more stable stage.
Naevus Pigmentosus
A light or dark brown, flush or raised birthmark, composed of naevus cells. If malignancy is suspected, the patient must be referred to a dermatologist who, if necessary, will consult a (plastic) surgeon. Usually, the dermatologist will excise the entire naevus. Diagnostic characteristics that are suspicious of malignancy include:
- Colour changes (especially to grey-blue).
- Irregular margins.
- Asymmetrical shape.
- Diameter > 6 mm.
- Itching.
- Bleeding.
- Rapid growth.
Reasons for treating: Cosmetic considerations or when the naevus is uncomfortable due to its location.
Therapy: Excision, whereby at least 2 mm of healthy skin must be co-excised. Always submit for anatomical-pathological assessment.
Subcutaneous Tumours
Dermoid Cyst
Subcutaneous cyst, surrounded by a thick, fibrous capsule and filled with sebum, hair, or keratin. These cysts arise during embryonic development when epithelial cells relocate to the subcutis due to invagination of the ectoderm.
Frequent sites: Around the eye, base of the nose, and forehead.
Reasons for treatment: Cosmetic considerations and the risk of malignant degeneration.
Therapy: Excision.
Epithelial Cyst
Subcutaneous cyst that occurs when cells from the epidermis are relocated to the subcutis due to trauma.
Frequent sites: Lines in the palm of the hand, soles of the feet, eyelid.
Reason for treatment: Cosmetic considerations or pain due to local pressure.
Therapy: Excision.
Lipoma
Subcutaneous tumour composed of fatty tissue. During palpation, the skin moves easily over the tumour. Lipomas can occur multiply.
Frequent sites: Neck, back, and buttock.
Reason for treatment: Pain due to local pressure, cosmetic considerations.
Therapy: Extirpation of a lipoma is best left to a surgeon. A tumour that is palpable on the surface is often the tip of the iceberg, extending to unexpected depths and widths. Lipomas that are already the size of a chestnut on palpation may extend far into deeper layers.