Untitled Editorial | Dermatol Pract Concept 2015;5(2):3 27 DERMATOLOGY PRACTICAL & CONCEPTUAL www.derm101.com Editorial In this edition Pyne et al have described a dermatoscopic pattern as a clue to infiltrative basal cell carcinoma (BCC), defined as: a geometric star-shaped pattern, extending out- wards from the circumferential peripheral edge of the tumor, and identified by white lines, vessels or uneven skin surface morphology. They found this clue present in 34/107 infiltrat- ing BCCs and in 37/634 non-infiltrating BCCs giving it a sen- sitivity of 31.7% and a specificity of 94.1% in their test series [1]. Is this a useful clue for the entity “infiltrative BCC” and will it influence patient management in any significant way? Infiltrative BCC is arguably the most elusive subtype and as such is the most likely subtype to invade widely and deeply before it is discovered and treated [2]. This explains why it is over-represented in BCCs that are more likely to recur after treatment and more likely to cause significant functional and cosmetic morbidity [2]. In assessing the impact of this clue the important question to consider is whether the presence of a stellate pattern will make infiltrative BCC more likely to be discovered, just as much as whether it will facilitate dis- tinction from other BCC subtypes. The former has arguably the more important impact, as it could lead to earlier cure, whereas distinction from other BCC subtypes is more relevant to method of treatment than to outcome. Dermatoscopic features can be divided into patterns and clues [3]. Patterns apply to the global appearance on the lesion and can lead to a differential diagnosis whereas clues are finer details that assist in reaching a provisional diagnosis [3]. Some dermatoscopic methods employ metaphoric termi- nology to describe patterns and colors [4-6] whereas others prefer geometric terminology [7]. The proponents of geometric terminology argue that in all other fields of medicine, description clearly precedes diag- nosis, except in that science of dermatoscopy, which employs metaphoric terminology. A potential problem with using a metaphor to describe this pattern in infiltrative BCC is the risk of applying a metaphor-based preconceived diagnostic implication at the time of lesion description. The feature which Pyne et al describe is a pattern con- structed by one of, or a combination of, three different derma- toscopic features: white radial lines, vessels in a radial pattern or 3-dimensional skin-folds in a radiating pattern. Although only one of the three features was needed for the pattern to be rated, the pattern was only significant with respect to dif- ferentiating infiltrative BCC from other subtypes if two or three of the features were present [1, table 4]. The authors discuss possible causes of this dermatoscopic sign. The images they display all show central ulceration, a known cause of a radial arrangement of vessels in BCC [8]. They found that both 50% of infiltrative BCC and 45% of nodular BCC, with stellate pattern, had central ulceration. Taking into account that ulceration in BCC can heal and therefore not be apparent dermatoscopically, ulceration, pres- Regarding a dermatoscopic pattern for infiltrating basal cell carcinoma Cliff Rosendahl1 1 School of Medicine, The University of Queensland, Australia Citation: [Editorial] Regarding a dermatoscopic pattern for infiltrating basal cell carcinoma. Dermatol Pract Concept 2015;5(2):3. http:// dx.doi.org/10.5826/dpc.0502a03 Copyright: ©2015 Rosendahl. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Corresponding author: Cliff Rosendahl, MBBS, PhD, PO Box 734, Capalaba, Queensland, 4157, Australia. Tel. +61 7 3245 3011; Fax. +61 7 3245 3022. Email: cliffrosendahl@bigpond.com 28 Editorial | Dermatol Pract Concept 2015;5(2):3 References 1. Pyne JH, Fishburn P, Dicker A, David M. Infiltrating basal cell carcinoma: a stellate peri-tumor dermatoscopy pattern as a clue to diagnosis. Dermatol Pract Concept 2015;5(2):2. 2. Hendrix JD, Parlette HL. Duplicitous growth of infiltrative basal cell carcinoma: Analysis of clinically undetected tumor extent in a paired case-control study. Dermatol Surg 1996;22(6):535–9. 3. Pehamberger H, Steiner A, Wolff K. In vivo epiluminescence mi- croscopy of pigmented skin lesions. I. Pattern analysis of pigmented skin lesions. J Am Acad Dermatol 1987;17(4):571–83. 4. Argenziano G, Fabbrocini G, Carli P, et al. Epiluminescence microscopy for the diagnosis of doubtful melanocytic skin le- sions. Comparison of the ABCD rule of dermatoscopy and a new 7-point checklist based on pattern analysis. Arch Dermatol 1998;134:1563–70. 5. Menzies SW, Ingvar C, Crotty K, McCarthy WH. Frequency and morphologic characteristics of invasive melanomas lacking specific surface microscopic features. Arch Dermatol 1996;132:1178–82. 6. Argenziano G, Soyer HP, Chimenti S, et al. Dermoscopy of pig- mented skin lesions: results of a consensus meeting via the Internet. J Am Acad Dermatol 2003;48(5):679–93. 7. Rosendahl C, Cameron A, McColl I, Wilkinson D. Dermatos- copy in routine practice—‘chaos and clues.’ Aust Fam Physician 2012;41(7):482–7. 8. Rosendahl C, Cameron A, Tschandl P, Bulinska A, Zalaudek I, Kit- tler H. Prediction without Pigment: a decision algorithm for non- pigmented skin malignancy. Dermatol Pract Concept 2014;4(1):9. ent or past, would be a plausible explanation for stellate pat- tern. The authors acknowledge the need for further studies, with dermatopathological correlation, to investigate this [1]. What we know from this study is that in a test series of known BCCs, the presence of a stellate dermatoscopy pattern will be present in approximately one third of the BCCs that have an infiltrative component, and in only approximately 6% of BCCs that do not [1]. Simply because of the prevalence of BCC, any flat, non-pigmented malignant lesion is most likely to be a BCC. Therefore it could appear reasonable to proceed to primary excision of any such lesion, without prior biopsy, if a stellate pattern is present, selecting excision margins appropriate for an aggressive BCC subtype. On the other hand, because it is not known what proportion of stellate-pattern lesions are benign, presumable scars, such a recommendation to proceed to excision without biopsy, cur- rently lacks a compelling evidence base. More importantly, if recognition of this stellate derma- toscopic pattern can be shown to improve the diagnostic sensitivity of infiltrative BCC in the clinical setting, so that lesions are detected that otherwise would have been missed, the recognition of this dermatoscopic pattern will have a significant practical benefit. Further studies to clarify these issues are appropriate.