Ann Dermatol.  2017 Feb;29(1):33-38. 10.5021/ad.2017.29.1.33.

Usefulness of Dermoscopy in the Differential Diagnosis of Ruptured and Unruptured Epidermal Cysts

• Suh KS
• Kang DY
• Park JB
• Yang MH
• Kim JH
• Lee KH
• Han SH
• Choi YD
• Kim ST
• Jang MS

• KMID: 2368025
• DOI: http://doi.org/10.5021/ad.2017.29.1.33

Abstract

BACKGROUND
An epidermal cyst is a common keratin-filled epithelial-lined cyst. The treatment of choice for epidermal cysts is surgical excision. If the cyst becomes ruptured, incision and drainage with oral antibiotic therapy or intralesional steroid injection are required.
OBJECTIVE
To analyze the dermoscopic features that can differentiate between ruptured and unruptured epidermal cysts.
METHODS
The clinical and dermoscopic features of the pathologically confirmed epidermal cysts of two subgroups of 38 patients, 20 with unruptured cysts and 18 with ruptured cysts, were reviewed.
RESULTS
With regard to the dermoscopic features, an ivory- white background color and punctum were commonly found in both groups (p>0.05). The unruptured-cyst group showed higher frequencies of pore sign (p<0.05), blue-white veil (p>0.05), no vascular structure, and arborizing telangiectasia (p<0.05), but the ruptured-cyst group usually had red lacunae (p>0.05) and peripheral linear branched vessels (with an erythematous rim) (p<0.05).
CONCLUSION
Dermoscopy is helpful in differentiating between ruptured and unruptured epidermal cysts.

Keyword

Dermoscopy; Epidermal cyst; Ruptured epidermal cyst; Unruptured epidermal cyst; Vascular structure

MeSH Terms

Dermoscopy*
Diagnosis, Differential*
Drainage
Epidermal Cyst*
Humans
Telangiectasis

Figure

• 

  Fig. 1 Ruptured epidermal cyst. (A) Erythematous 2×2 cm subcutaneous nodule. (B) Dermoscopic view showing peripheral linear branched vessels with an erythematous rim (arrowheads) against an ivory-white background. (C) Microscopic view showing a cystic lesion with dense inflammation surrounding the ruptured cyst (patient 5 in the ruptured-cyst group).

• 

  Fig. 2 Unruptured epidermal cyst. (A) Well-demarcated bluish 2×2 cm subcutaneous nodule. (B) Dermoscopic view showing a arborizing telangiectasia consisting of vessels with different diameter and several branches. (C) Microscopic view showing prominent dilated vessels with congestion of blood flow between the epidermis and cystic wall (patient 9 in the unruptured-cyst group).

• 

  Fig. 3 Schematic representation of dermoscopic pattern in patient with unruptured cyst and ruptured cyst.

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