PassFinals
Dermatology

Melanoma

Melanoma is malignant melanocytic disease requiring rapid specialist assessment, histological staging and stage-directed treatment; a changing pigmented lesion should not be reassured by a single visual rule.

In a nutshell

Melanoma is a changing or atypical melanocytic lesion requiring specialist dermoscopy and histology. Use the NICE 7-point checklist for referral, stage with Breslow/ulceration/nodes, apply stage-specific excision margins and reserve SLNB/imaging for the NICE indications.

Classic presentation

Evolving pigmented lesion with asymmetry, irregular border, colour variation or a new 'ugly duckling' lesion; may bleed or become nodular.

Key points

  • NICE NG12: suspected-cancer referral for a pigmented lesion with weighted 7-point checklist score 3 or more.
  • Dermoscopy must be performed by trained clinicians in secondary/tertiary assessment; visual ABCDE alone cannot rule out melanoma.
  • Histology reports Breslow thickness, ulceration, mitotic activity and margins; these drive stage and management.
  • Do not offer imaging or SLNB for stage IA. Consider SLNB at 0.8 to 1.0 mm with ulceration/LVI/mitotic index 2 or more, and above 1.0 mm.
  • NICE excision margins: at least 0.5 cm for stage 0, 1 cm for stage I and 2 cm for stage II, with specialist adjustment for morbidity.
  • Stage IIB imaging is considered; stage IIC to IV imaging is offered, with MRI alternatives in selected pregnancy/young-person pathways.
  • Stage III/IV treatment is MDT- and biomarker-specific; BRAF testing is selective, not a screening test.

First-line investigation

Urgent specialist dermoscopy and histological diagnosis of a suspicious lesion.

Management

Refer suspicious lesions

  • Use NG12 weighted checklist and urgent suspected-cancer referral; safety-net evolving or clinically suspicious lesions even when the score is low.1,2

Dermoscopy and histology

  • Use trained dermoscopy and obtain tissue diagnosis with Breslow, ulceration, mitotic and margin reporting.2

Excise local melanoma

  • Apply NICE stage-specific clinical margins and discuss selected stage 0 imiquimod only when surgery causes unacceptable morbidity.2

Stage nodes and metastases selectively

  • Use the NICE SLNB thresholds and stage-specific CT/MRI pathway; discuss pregnancy and young-person imaging with the specialist MDT.2

Use specialist systemic/oncology pathways

  • Stage III/IV treatment, BRAF testing, immunotherapy, targeted treatment, surgery and radiotherapy are MDT decisions using current NICE technology appraisals.2,3

Support and surveil

  • Give self-examination, sun-protection and psychological support, with stage-specific and risk-tailored follow-up.2,4

Exam traps

  • A lesion can be amelanotic or on an acral/nail site; absence of black pigment does not exclude melanoma.
  • A normal ABCDE screen does not override evolution or an ugly-duckling lesion.
  • Breslow thickness is not the same as the clinical diameter of the lesion.
  • SLNB is selective and is not offered for stage IA.
  • A changing lesion should not be repeatedly treated as a benign naevus without specialist reassessment.

Illustrations

ABCDE features of melanomaSide-by-side clinical photographs comparing a benign naevus with a melanoma showing asymmetry, border irregularity and colour variation.Unknown creator, Wikimedia Commons · Public domain
Breslow thickness diagramCross-sectional diagram of skin showing how Breslow thickness is measured from the granular layer to the deepest invading tumour cell.PassFinals · original
Dermoscopic appearance of melanomaDermoscopy of a superficial spreading melanoma showing an atypical, broadened pigment network, irregular pigmentation and white regression areas.Juliana Casagrande Tavoloni Braga, Mariana Petaccia Macedo, Clovis Pin, Wikimedia Commons · CC-BY-4.0

Key sources

  1. NICE NG12: Suspected cancer recognition and referral — melanoma (Weighted 7-point checklist and suspected-cancer referral threshold)Published 23 Jun 2015
  2. NICE NG14: Melanoma: assessment and management (Current assessment, staging, excision, systemic-treatment and follow-up recommendations)Published 29 Jul 2015 | Updated 27 Jul 2022
  3. NICE NG14: Update information (2022 surveillance update and 2024 BRAF wording changes)Updated 1 Jan 2024
  4. NHS: Melanoma skin cancer (Symptoms, diagnosis, treatment and safety-netting information)

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.