A Pathologist’s Guide to Skin Cancer for practitioners
With summer around the corner, patients tend to find moles and bumps that have been hidden under winter clothing. Clinical Labs’ expert dermatopathologist, Dr Alex Nirenberg, provides some tips for how doctors can take optimal samples to help pathologists analyse and diagnose suspicious moles and bumps.
Taking appropriate biopsies: the type of biopsy depends on the type of lesion
Small curettes offer limited information. Shave biopsies are good for superficial lesions.
For deep lesions punch biopsies are better. Remember to take the thickest part of a tumour, avoiding necrotic or scarred areas - 4mm punches or larger are best. Where possible, remove suspicious pigmented lesions in their entirety.
For larger specimens, if re-excision is needed, you will know which edge to take more tissue from. Use a nick or a suture, e.g. at 12 o'clock. A line drawing on the request slip will aid the pathologist.
Following up patients
If following up a lesion over time, use photography to document the lesion at each visit. This better allows recognition of changes with time, especially if the changes are subtle.
New melanoma staging
The AJCC staging manual is now in its 8th edition. There is an important update to the staging of thin melanomas which better reflects prognosis:
- Stage T1a melanoma <0.8mm, without ulceration
- Stage T1b melanoma <0.8mm with ulceration or melanoma 0.8-1.0mm, with or without ulceration
Update your knowledge and earn CPD points:
Australian Clinical Labs runs a Skin Excision Evaluation Program which is eligible for CPD points for the RACGP.
The Australasian College of Cutaneous Pathology runs a series of practical workshops on Skin Cancer management, including dermoscopy and pathology. Visit www.acco.edu.au for more information.