Excision margins for melanoma redefined

Excision margins for melanoma redefined

21 February 2018

Research results from Melanoma Institute Australia (MIA) have been used to help define appropriate excision margins in patients with primary cutaneous melanoma.

MIA has been working with Cancer Council Australia since 2016 to develop new evidence-based Australian guidelines for the management of melanoma. The guidelines are designed to promote optimal practice management for patients with melanoma.

One of the topics addressed in the new guidelines is excision margins for primary cutaneous melanoma. Surgical excision remains the first line of defence in most patients with a primary melanoma of the skin, and 85%–90% of patients will be cured at this stage of treatment.

Understanding how much skin surrounding the tumour must be removed remains a point of contention for many clinicians. It is important to find the balance between resecting enough skin to limit the potential for recurrence, while having the least impact on patients and limiting unnecessary expense to the health system.

This challenge faced by clinicians has led to the development of evidence-based surgical excision guidelines. A paper published today in the Medical Journal of Australia provides clinicians with details of the updated guidelines that will help guide clinical decision making.  

The recommendations for definitive wide local excision of primary cutaneous melanoma in the new guidelines are:

  • Melanoma in situ: 5–10 mm margins
  • Invasive melanoma (pT1) ≤ 1.0 mm thick: 1 cm margins
  • Invasive melanoma (pT2) 1.01 mm–2.00 mm thick: 1–2 cm margins
  • Invasive melanoma (pT3) 2.01 mm–4.00 mm thick: 1–2 cm margins
  • Invasive melanoma (pT4) > 4.0 mm thick: 2 cm margins

Professor John Thompson AO, Senior Surgeon at MIA and chairman of the Guidelines Working Party, commented: “Adherence to the recommended excision margin guidelines will help to minimise the risk of melanoma recurrence by ensuring that adequately wide excision is performed, while reducing the risk of complications and morbidity by avoiding unnecessarily extensive surgery.”


Sladden MJ, Nieweg OE, Howle J, Coventry BJ and Thompson JF. (2018) Updated evidence-based clinical practice guidelines for the diagnosis and management of melanoma: definitive excision margins for primary cutaneous melanoma. MJA [ePub]