01Purpose and principlesWhat the treatment does and how it fits into care.
Separate diagnosis, local control and regional staging. The initial narrow full-thickness excision supplies Breslow depth and ulceration. The specialist multidisciplinary team then assigns pathological stage, plans a wider clinical margin around the scar and decides whether sentinel-node staging or imaging is relevant. Presenting all three as one operation obscures why the sequence matters.
A wider margin removes microscopic local extension but does not compensate for a transected diagnostic biopsy. Stage 0 remains epidermal and uses at least 0.5 cm; stage I uses 1 cm; stage II uses 2 cm unless morbidity makes 1 cm the shared alternative. Site, reconstruction and function require plastic, head-and-neck, hand or other specialist input but should not silently reduce oncological planning.
SLNB maps lymphatic drainage with tracer and removes the first node or nodes for histology. Explain possible seroma, infection, sensory change, lymphoedema and false-negative results. It provides prognosis and access to stage-specific adjuvant discussions but is optional after informed conversation. Pregnancy can justify delaying SLNB until after completion, as NICE advises discussing.
Follow-up is not only a scan schedule. Clinical examination, self-awareness, sun protection, new-primary risk, treatment toxicity, fertility, work, anxiety and rapid symptom access all matter. Imaging is stage directed because repeated scans can detect recurrence but also create radiation, incidental findings and distress. Provide a written personalised plan and the route back between appointments.
Key points
- Diagnostic excision removes the suspicious lesion completely with a narrow margin to establish melanoma diagnosis, Breslow depth, ulceration and pathological stage.
- Wide local excision is a second procedure around the biopsy scar; its clinical margin is determined by stage and includes the initial primary-lesion margin.
- NICE advises at least 0.5 cm for stage 0, 1 cm for stage I and 2 cm for stage II, using 1 cm if a 2 cm margin would cause unacceptable disfigurement or morbidity.
- Sentinel lymph-node biopsy is a staging procedure for clinically node-negative melanoma; it does not treat the primary lesion and has not itself been shown to improve survival.
- Do not offer imaging or SLNB for stage IA melanoma and do not perform routine imaging before SLNB unless nodal or distant metastasis is suspected.
- Consider SLNB for Breslow 0.8–1.0 mm with ulceration, lymphovascular invasion or mitotic index 2 or more, and for Breslow thickness over 1.0 mm.
- A positive sentinel node changes pathological stage and adjuvant-treatment discussion; routine completion lymph-node dissection is not automatic.
- Follow-up intensity is stage based and includes whole-skin, scar, in-transit and nodal examination, self-examination education, psychosocial support and rapid re-entry for symptoms.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Wide-excision measurement surrounds the complete diagnostic scar and accounts for the margin already taken around the primary lesion.
SLNB applies when no nodal metastasis is detected clinically or on indicated assessment and microscopic staging remains relevant.
A new dermal or subcutaneous nodule between the primary scar and draining nodal basin can represent lymphatic melanoma spread.
A firm enlarging node in the expected basin requires urgent ultrasound and tissue diagnosis rather than observation.
New focal neurology, persistent headache, bone pain, breathlessness or constitutional decline needs stage-aware urgent investigation.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Complete diagnostic histopathologyFirst step - Why
- Provide Breslow thickness, ulceration, margins and adverse features before definitive planning.
- Interpretation and limitations
- If the deep margin is transected, true depth may be underestimated and the multidisciplinary team must plan further staging cautiously.
- 02
Sentinel lymph-node biopsy - Why
- Detect clinically occult regional nodal metastasis and refine pathological stage and prognosis.
- Interpretation and limitations
- Consider at 0.8–1.0 mm with specified adverse features and over 1.0 mm; do not offer for stage IA.
- 03
Sentinel-node histopathology - Why
- Determine whether microscopic melanoma is present and quantify burden for stage and adjuvant decisions.
- Interpretation and limitations
- A positive result does not automatically require completion node dissection; specialist ultrasound surveillance and systemic options are considered.
- 04
Stage-directed CT, MRI or PET-CT - Why
- Assess regional or distant disease when stage or symptoms justify imaging.
- Interpretation and limitations
- Do not image routinely before SLNB without suspected metastasis; modality and interval follow current NICE stage recommendations.
- 05
Follow-up skin and node examination - Why
- Detect local recurrence, in-transit disease, nodal spread and new primary melanoma.
- Interpretation and limitations
- Examine scar, intervening lymphatic skin, basin and full skin; patient-reported evolution can prompt biopsy between scheduled visits.
04Treatment approachPreparation, options, escalation and aftercare.
01After diagnostic excisionConvert histology into local controlFirst stepA completely sampled primary lesion is confirmed as stage 0, I or II melanoma.+
- 1Review Breslow depth, ulceration, biopsy margins and stage in the specialist skin-cancer multidisciplinary team.
- 2AlternativePlan wide local excision around the histological scar using at least 0.5 cm for stage 0, 1 cm for stage I and 2 cm for stage II unless morbidity dictates the NICE alternative.
- 3Coordinate reconstruction and verify final margins, preserving function without losing the intended oncological field.
02Sentinel-node decisionOffer informed staging selectivelyClinically node-negative invasive melanoma falls within a NICE SLNB consideration group.+
- 1Do not offer SLNB for stage IA; consider it for 0.8–1.0 mm with ulceration, lymphovascular invasion or mitotic index at least 2, and over 1.0 mm.
- 2Explain prognostic and adjuvant-treatment value, lack of direct primary treatment, false negatives and surgical adverse effects, then respect informed choice.
- 3Use the result to refine stage and specialist treatment or ultrasound surveillance without automatic completion node dissection.
03Risk-stratified follow-upCombine surveillance and rapid accessDefinitiveDefinitive primary treatment and staging are complete.+
- 1Provide a written stage-specific schedule for clinic and imaging where NICE recommends it, including who owns each result.
- 2At visits examine full skin, scar, in-transit pathway and nodes and address treatment toxicity, lymphoedema, mental health and function.
- 3Teach monthly self-examination and give an urgent contact route for new lesions, scar nodules, nodes or organ symptoms rather than waiting for the next appointment.
05Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Confirm final wide-excision histological margins and resolve any involved margin in the multidisciplinary team.
- After SLNB monitor wound, seroma, infection, sensory change and limb or basin swelling and communicate pathology promptly.
- At every follow-up document scar, in-transit skin, regional nodes and a complete skin examination plus patient-reported symptoms.
- Track stage-directed imaging completion and incidental findings through a named clinician to avoid orphaned results.
- Screen for anxiety, fear of recurrence, lymphoedema, work and financial impact and provide melanoma support and rehabilitation routes.
06Special situationsVariants, exceptions and circumstances that change the usual approach.
Margins answer different questions
Narrow biopsy establishes diagnosis and thickness; wider re-excision reduces local recurrence after stage is known.
Sentinel means first draining
Tracer identifies the initial nodal destination, which may not be the basin predicted from surface anatomy alone.
Staging is not therapy
A negative SLNB does not treat the primary, while a positive SLNB mainly changes stage and subsequent options.
Follow-up includes new primaries
Surveillance searches not only for recurrence but also another independently arising melanoma or keratinocyte cancer.
Rapid access protects intervals
A perfect routine schedule fails if a new node must wait months for the next booked appointment.
07Common pitfallsFrequent interpretation and management errors.
- 01
Using the narrow diagnostic margin as definitive wide-excision treatment for invasive melanoma.
- 02
Offering SLNB to stage IA melanoma contrary to NICE guidance.
- 03
Describing sentinel-node biopsy as a treatment guaranteed to improve survival.
- 04
Ordering routine pre-SLNB imaging without clinical suspicion of metastasis.
- 05
Providing scheduled follow-up without a route for urgent assessment between appointments.