Scars - hypertrophic and keloid

This chapter discusses keloid scars, which extend beyond the original defect/scar and persist for many years, and hypertrophic scars, which are smaller, remain confined to the initial defect/scar and tend to improve with time.

This chapter is set out as follows:

• Hypertrophic and keloid scars represent an excessive connective tissue response:
• to an injury (eg accidental trauma, burn, piercing etc), which may be trivial;
• following surgery;
• sometimes following inflammation (eg acne vulgaris, chickenpox);
• and occasionally arising spontaneously, especially on the upper trunk

• Scars can arise at any age and site but the following increase the risk:
  • Site - upper trunk, upper arms, shoulders, neck and earlobes
  • Age - younger patients, most keloid scars arise between puberty and the age of 30
  • Skin type - especially skin types V-VI, skin type I is also at increased risk
  • A family history of keloid scars
  • Women more than men 
  • Poor wound healing as a result of eg secondary infection or retained suture material

• Lesions tend to appear a few weeks after the injury, but sometimes arise much later
• Occasionally there is no history of preceding injury or inflammation
• Growth can continue for months or years
• Symptoms - many patients complain of tenderness or itch

• A firm, skin-coloured to red, plaque or nodule, which can take on a dumbbell shape
• Size varies, some keloid scars can be very large
• If the lesion appears atypical consider dermatofibrosarcoma protuberans

Step 1: scar prevention

• Avoid unnecessary skin surgery

• When surgery is required and the patient has a higher risk of scarring:
• The patient should be treated by a health professional who has had the necessary training and is able to perform skin surgery to a high standard
• Silicone gel / sheets, used post operatively for several months will reduce scar formation in some patients

• Acne - patients known to suffer from keloid scars and who develop even mild acne require prompt and effective treatment for their acne

Step 2: treatment of scars

• For keloid scars provide a patient information leaflet

• Following any given treatment recurrence rates vary from 9-50%

• Silicone gel / sheets

• Some patients may benefit if silicone is used either as a preventative treatment or at a very early stage of scar development 
• Treatment is required for several months

• Steroid treatments

• If used in the early days of scar formation, a potent or super-potent topical steroid eg Dermovate ® ointment applied thinly once daily (for several months) may be of benefit. Alternatively, consider steroid impregnated treatments - there are two types, both of which can be left on for up to 24 hours before reapplying:
  • Haelan ® tape (fludroxycortide tape) - attached is a video demonstrating how to use the tape
  • Betesil ® medicated plaster (betamethasone valerate 2.25mg) - attached is a video demonstrating how to use the plaster

• The most effective treatment is intralesional steroid therapy, using triamcinolone acetonide as follows:
  • A high pressure is needed for effective infiltration of the lesion, which can be achieved by using a 1 ml insulin syringe. If the scar is large or numerous, treatment is best given using a needleless medical instrument known as Dermojet ®, which is normally available in dermatology out-patients
  • Multiple treatments are often required
  • Patients need to be warned that while intralesional steroid therapy is likely to flatten scars and make them more comfortable, it is associated with adverse effects such as telangiectasia and a darkening of the treated area / surrounding skin 

• Cryosurgery can by an effective treatment in some patients, especially for small scars of recent onset 

• Other treatments

  • Many other treatments have been used including photodynamic therapy, laser therapy, radiotherapy, intralesional bleomycin and intralesional 5-FU 
  • All studies on the above have been very small

• Surgery - shave / elliptical excision

  • Should be seen as a last resort as it may lead to the development of a larger keloid scar, such a treatment must only be considered by an experienced surgeon
  • Surgery is often combined with another treatment modality such as intralesional steroid therapy. Patients require close follow-up