Nine practice points from the new melanoma guidelines
By Rachel Worsley
17 November 2016
Australian melanoma clinical practice guidelines have been published on a wiki platform for the first time as researchers try to keep up to date with emerging evidence.
Professor John Thompson, Melanoma Institute Australia's Executive Director and chair of the guidelines expert working group, says publication on the Cancer Council Australia’s wiki means advice can be continually reviewed and updated as new evidence comes to light.
“Things are moving quickly in melanoma management,” he says.
The guidelines cover recognition of melanomas, biopsy of suspicious lesions, when to perform sentinel node biopsy (SNB) and margins for radical excision of primary melanomas.
“This is particularly important, given the advent of new effective but high cost drugs that may be of value in appropriately staged patients,” Professor Thompson says.
Here are nine highlights:
- Careful history taking is critical and any lesion that continues to grow or change in size, shape, colour or elevation over a period of more than one month should be biopsied and assessed histologically or referred for expert opinion.
- Raised lesions should not be just monitored, they should be biopsied.
- The best biopsy approach for a suspicious pigmented lesion is complete excision with a 2mm clinical margin and upper subcutis.
- Punch biopsy should not be used for the routine diagnosis of suspected melanoma because of high rates of histopathological incorrect false negatives.
- Where a punch biopsy has been done for suspected BCC or SCC and the diagnosis has been found to be melanocytic, then excision of the entire lesion should be considered.
- Deep shave excision should be limited to in situ or superficially invasive melanomas to preserve prognostic features and optimize accurate planning of therapy.
- Partial biopsies may not be fully representative of the lesion and should be interpreted with caution to minimise incorrect false negative diagnoses and under-staging.
- In carefully selected clinical circumstances (such as large in situ lesions, large facial or acral lesions or where the suspicion of melanoma is low), and in the hands of experienced clinicians, punch or shave biopsies may be appropriate.
- Consider sentinel node biopsy for melanoma greater than 1mm in thickness and melanoma greater than 0.75mm with high risk pathological features. SNB should be performed in a centre with expertise in the procedure, including nuclear medicine, surgery and pathology.
You can access a guideline summary here.
(Article originally published in Medical Observer)