Cancer Council Australia · NHMRC · BAD/AAD consensus · MBS Book July 2026
| Diagnosis | Clinical margin | Notes |
|---|---|---|
| BCC — superficial/nodular | 3–4 mm | 3mm adequate for small, well-defined nodular BCC. 4mm for larger. Morphoeic/infiltrative: 5mm minimum. |
| BCC — morphoeic/infiltrative | 5 mm minimum | Consider Mohs/specialist referral for H-zone or recurrent. |
| SCC — low risk | 4 mm | Well-differentiated, <2cm, not on high-risk site, no PNI. 4mm margin provides >95% clearance. |
| SCC — high risk | 6 mm | ≥2cm, poorly differentiated, PNI, recurrent, H-zone, immunosuppressed. Consider specialist referral. |
| Melanoma in situ (MIS) | 5 mm | 5mm margins for standard MIS. Lentigo maligna: 5–10mm, consider mapping biopsies. |
| Melanoma <1mm (T1) | 10 mm | 1cm margin adequate for thin melanomas (≤1mm Breslow thickness). |
| Melanoma 1–2mm (T2) | 10–20 mm | 1–2cm margin. Site and patient factors influence final margin. |
| Melanoma >2mm (T3/T4) | 20 mm | 2cm margin standard. Wide local excision, usually specialist. |
| Melanoma — unknown thickness | 10 mm (await histology) | Excise with 1cm margin if thickness unknown; re-excise when Breslow depth confirmed. |
| AK / Bowen’s / IEC | 2–3 mm | Can also treat with topical agents (Efudix, Aldara) or cryotherapy if multiple lesions. |
| Keratoacanthoma | 4 mm | Treat as SCC low-risk unless cannot be confidently distinguished. |
| Benign lesion | 1–2 mm | Margin for cosmesis and complete removal; no oncological margin required. |