When a clinically suspicious pigmented lesion is biopsied and histologic examination shows melanoma, tumor depth, or Breslow’s depth (BD), is the key parameter that both determines surgical margins for definitive excision and serves as an indication to perform sentinel lymph node biopsy (Smith and MacNeil, 2011). Optimally, BD is measured during an initial excisional biopsy that includes the entire lesion. However, in many cases an incisional biopsy is performed that takes a sample of only a portion of the tumor, possibly resulting in an inaccurate measurement (Guitera and Menzies, 2011; Sellheyer et al., 2010).
