We are concerned about the recently published video by Czarnowski et al, which teaches the procedure of punch biopsy on a pigmented lesion.1 Although punch biopsy is a useful skill in primary care dermatology in some circumstances, it is generally inappropriate for the diagnosis of pigmented lesions.
Guidelines from around the world recommend excisional (rather than incisional) biopsy of suspicious pigmented lesions.2,3 Incisional biopsies, such as punch biopsies, risk sampling error. For example, areas of invasive melanoma might be present in an excisional specimen but missed in a smaller biopsy.4 Also, different but contiguous pigmented lesions commonly exist5; sampling only the benign lesion can lead to missed or delayed diagnosis of a malignancy, with potentially hazardous consequences.
Possible indications for incisional biopsy of pigmented lesions include very large lesions for which excisional biopsy would be difficult, such as large macular pigmented facial lesions.3 Even in these cases, the use of punch biopsy in diagnosing melanocytic lesions is potentially perilous, and according to British guidelines, “there is no place for incisional biopsy in primary care.”2 We recommend that incisional biopsy in primary care be limited to nonpigmented lesions and rashes.
- Copyright© the College of Family Physicians of Canada
