Keloid scar
Cheloid; keloid scarring; abnormal fibrous scar
Keloid is a benign but disfiguring fibroproliferative scar that extends beyond the original wound margin — distinguishing it from a hypertrophic scar, which respects the original wound. It is far commoner and more severe in Fitzpatrick IV–VI skin (genetic predisposition; 5–15× higher prevalence than Fitzpatrick I–III). Earlobes, presternal chest, upper back, deltoid and posterior neck are predilection sites. A long-standing rapidly enlarging keloid is occasionally biopsied as suspected dermatofibrosarcoma protuberans — the major skin-oncology differential. Treatment is multimodal — intralesional steroid + 5-fluorouracil, silicone, cryotherapy, surgical excision with adjuvant radiotherapy. Recurrence is the norm; setting expectations is essential.
Clinical features
- Firm, raised, shiny, pink-violet to brown scar extending beyond the original wound or injury margin.
- Onset weeks to years after initial wound (acne, piercing, surgery, vaccination, trauma).
- Pruritus and pain common; spontaneous regression is rare.
- Common sites — earlobes (piercings), presternum, upper back / shoulder (acne), deltoid, posterior neck. Mid-face / scalp / eyelids rarely affected.
- Fitzpatrick IV–VI substantially over-represented; family history strong.
Hypertrophic scar vs keloid vs DFSP
- Hypertrophic scar — confined to the original wound margin; often regresses over 1–2 years; less symptomatic.
- Keloid — extends beyond the original wound; persistent; bothersome.
- DFSP — primary indolent mesenchymal tumour; nodules within an indurated scar-like plaque; often on trunk; CD34+, COL1A1-PDGFB fusion. Biopsy any keloid that becomes nodular, rapidly enlarges, or develops in an atypical site.
- Lobomycosis, dermatofibroma, hypertrophic lichen planus, keloid acne — other DDx in selected contexts.
Management
- Multimodal combination is more effective than monotherapy. Common combinations:
- Intralesional triamcinolone 10–40 mg/mL every 4–6 weeks for 3–6 cycles.
- Intralesional 5-fluorouracil 50 mg/mL (alone or mixed with triamcinolone 90:10 ratio) — improved efficacy with reduced steroid atrophy.
- Silicone sheets / gel — daily for ≥ 12 hours, for at least 3 months.
- Pressure therapy — particularly for earlobe keloids (pressure earring).
- Cryotherapy — intralesional or surface; reduces volume.
- Surgical excision — only when combined with adjuvant intralesional triamcinolone + 5-FU or with adjuvant radiotherapy (single dose 12 Gy within 24 hours). Recurrence without adjuvant is > 50%.
- Laser — pulsed dye laser for erythema; fractional ablative laser for texture.
- Persistent / recurrent keloid — refractory; combination IL-bleomycin, imiquimod 5% post-excision, or specialist scar service.
- Counselling — set realistic expectations: improvement, not necessarily resolution; recurrence common; ongoing maintenance.
Prevention in at-risk patients
- Avoid elective surgery / piercings on high-risk sites (presternum, deltoid, earlobe) in keloid-prone patients.
- Optimise wound healing — tension-free closure, layered closure, antiseptic care, infection prevention.
- Silicone sheet / gel prophylactically on healing wounds for 3 months.
- Post-surgical pressure therapy for at-risk sites.
- Steroid injection at suture removal in selected high-risk cases.
References
- Mustoe TA et al. International clinical recommendations on scar management. Plast Reconstr Surg; 2002.
- Berman B et al. Keloid and hypertrophic scar — review. J Am Acad Dermatol; 2017.
- Ogawa R. Keloid and hypertrophic scars — current understanding and treatment. Plast Reconstr Surg; 2010.
Spot a correction?
If any clinical statement, citation or link on this page needs updating, please email admin@skinoncology.net with the page name, the proposed correction and the supporting source.