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Dermatology

Benign skin lesions

Benign skin lesions are common non-malignant growths such as seborrhoeic keratoses, epidermoid cysts, dermatofibromas, skin tags, lipomas and naevi; the high-yield skill is recognising reassuring patterns while identifying the changing, symptomatic or atypical lesion that needs specialist assessment or biopsy.

In a nutshell

Common benign lesions include seborrhoeic keratoses, epidermoid cysts, dermatofibromas, skin tags, lipomas and stable naevi. Diagnose the pattern and assess evolution; reassure only when the benign diagnosis is convincing. Actinic keratosis is pre-malignant, while changing, irregular, bleeding, ulcerated or non-healing lesions need appropriate dermatology or suspected-cancer referral.

Classic presentation

An older adult has a stable, sharply demarcated waxy or verrucous lesion with a stuck-on appearance, or a mobile nodule with a punctum consistent with an epidermoid cyst; there is no concerning evolution.

Key points

  • Seborrhoeic keratoses are waxy or verrucous and stuck-on; epidermoid cysts often have a punctum; dermatofibromas may dimple; lipomas are soft and mobile.
  • Evolution is the key safety question: ask about change in size, shape, colour, surface, sensation, bleeding and ulceration.
  • Use the NICE weighted 7-point checklist for suspicious pigmented lesions; a score of 3 or more merits suspected-cancer pathway referral.
  • Actinic keratosis is pre-malignant and needs treatment or monitoring, not simple reassurance.
  • Do not destructively treat a lesion that could be melanoma; arrange appropriate specialist assessment and histology.
  • Benign lesion removal is generally for symptoms, recurrent infection, trauma, functional impact or diagnostic need; cosmetic access varies by local NHS policy.
  • Give UV-protection and clear safety-netting advice even after a benign diagnosis.

First-line investigation

Full skin examination with dermoscopy where trained and a careful history of evolution; use specialist assessment or biopsy when the diagnosis is uncertain.

Management

Describe and risk-assess the lesion

  • Examine the whole lesion and surrounding skin, ask about evolution and symptoms, and use dermoscopy or specialist advice when the benign pattern is not convincing.1,2

Reassure or observe when diagnosis is secure

  • For an asymptomatic lesion with a confident benign diagnosis, explain the expected course and provide safety-netting rather than arranging routine removal; discuss local criteria if the patient requests treatment.3,1

Treat symptomatic or pre-malignant lesions appropriately

  • Treat actinic keratosis through the appropriate lesion-directed or field-treatment pathway and consider removal of a benign lesion only for symptoms, repeated trauma, infection, functional effect or diagnostic need.4,3,6

Refer lesions suspicious for cancer

  • Use NICE NG12 criteria for suspected melanoma, squamous cell carcinoma and selected basal cell carcinoma; do not destructively treat a lesion that could be melanoma before specialist assessment.2,5

Protect skin and safety-net

  • Advise sensible UV protection and ask the patient to return for evolution, bleeding, ulceration, persistent crusting, pain, rapid growth or failure to heal.4,2

Exam traps

  • A stuck-on appearance supports seborrhoeic keratosis but does not overrule evolution, bleeding or atypical pigmentation.
  • A stable benign naevus is not the same as a changing pigmented lesion; use the NICE weighted 7-point checklist and dermoscopy pathway.
  • Actinic keratosis is a pre-malignant keratinocytic lesion, not a harmless benign skin tag.
  • Do not shave or curette a lesion that could be melanoma.
  • A painful, rapidly enlarging or fixed subcutaneous mass should not be labelled a lipoma without appropriate assessment.
  • Cosmetic removal criteria are local NHS commissioning decisions, not a universal clinical rule.

Illustrations

Multiple seborrhoeic keratosesA clinical photograph showing sharply demarcated, brown, waxy or verrucous lesions with a stuck-on appearance, with a legend warning that atypical or changing lesions still require assessment.James Heilman, MD, Wikimedia Commons · CC-BY-SA-3.0

Key sources

  1. British Association of Dermatologists: Dermatology Referral Management Guidelines (UK dermatology referral resource covering common benign and malignant mimics, clinical description, diagnostic tips and when to seek specialist or teledermatology advice; accessed 4 August 2026.)
  2. NICE NG12: Suspected cancer: recognition and referral (Current NICE skin-cancer referral criteria, including the weighted 7-point checklist for melanoma and referral guidance for melanoma, squamous cell carcinoma and basal cell carcinoma; last updated 15 April 2026 and accessed 4 August 2026.)Updated 15 Apr 2026
  3. NHS clinical policy: Surgical removal of benign skin lesions (UK NHS policy describing diagnostic certainty and symptomatic or clinically necessary indications for removal of common benign lesions, with local commissioning variation; accessed 4 August 2026.)
  4. NICE PH32: Sunlight exposure: risks and benefits (NICE skin-cancer prevention and sensible sun-protection advice; last updated 9 February 2016 and accessed 4 August 2026.)Updated 9 Feb 2016
  5. NICE NG14: Melanoma: assessment and management (NICE melanoma diagnostic and management framework used for the biopsy and specialist pathway context; last updated 27 July 2022 and accessed 4 August 2026.)Updated 27 Jul 2022
  6. British National Formulary (BNF) (BNF online prescribing information for topical treatments relevant to actinic keratosis and lesion-related treatment decisions; accessed 4 August 2026.)

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.