Universitas Muhammadiyah Sidoarjo
Login


Indonesian Journal on Health Science and Medicine

 Submit manuscript
Section Articles

A Comprehensive Review of Keratinous Cysts: Etiology, Diagnosis, and Management

Vol. 2 No. 2 (2025): Oktober:
DOI : https://doi.org/10.21070/ijhsm.v2i2.269
Published : Sep 24, 2025

Qabas M Hameed Al Anni (1), Ramzy Kaddim Hassan (2), Qasim Abdulrasol Mohammed (3), Diyar Iqbal Kadhim (4)

(1) Collage of Dentistry Al Hadi University, Iraq
(2) Collage of Dentistry Al Hadi University, Iraq
(3) College of Dentistry Al-Hadi University, Iraq
(4) College of Dentistry Al-Hadi University, Iraq
Fulltext View | Download

Abstract:

Keratinous cysts, predominantly referred to as epidermoid cysts (ECs) or epidermal inclusion cysts (EICs), represent the most prevalent subtype of cutaneous cysts. These benign, slow-growing lesions are defined by a pathological cavity situated within the dermis or subcutis, lined by stratified squamous epithelium and filled with macerated keratin and lipid-rich debris. While often asymptomatic, their clinical significance arises from a high frequency of complications, including inflammation, infection, and rupture, which prompt medical consultation. Furthermore, their presentation can mimic a wide range of other soft tissue tumors, necessitating accurate diagnosis. This paper provides a exhaustive, systematic review of keratinous cysts, delving into their historical context, precise nomenclature, and epidemiological patterns. It elaborates on the multifactorial etiologies and molecular pathways underpinning their pathogenesis. The clinical and histopathological features are described in detail, alongside advanced diagnostic imaging characteristics. A critical analysis of the differential diagnosis is presented, followed by a comprehensive discussion on management strategies, from conservative approaches to sophisticated surgical techniques aimed at minimizing recurrence and optimizing cosmetic outcomes. The paper also explores rare associations and future research directions, consolidating current evidence to serve as a definitive reference for dermatologists, surgeons, and primary care physicians. condition.
Highlights:
1.     Keratinous cysts, including epidermoid and epidermal inclusion cysts, are the most common cutaneous cysts with significant clinical impact when complicated.
2.     Accurate diagnosis requires distinguishing them from other cystic and tumor-like lesions using clinical, histological, and imaging features.
3.     Management ranges from observation and intralesional corticosteroids to complete surgical excision, with prognosis generally excellent after definitive treatment.

References

[1] V. T. Hoang and T. A. Le, Epidermal Inclusion Cyst, in StatPearls. Treasure Island, FL: StatPearls Publishing, 2023.

[2] D. Weedon, Weedon’s Skin Pathology, 5th ed. Elsevier, 2019.

[3] P. C. Alguire and B. M. Mathes, Epidermal Inclusion Cysts: Diagnosis and Management. UpToDate, 2023.

[4] H. S. Lee and J. H. Kim, “Clinical characteristics of epidermoid cysts: A retrospective analysis of 1,011 patients,” Ann. Dermatol., vol. 32, no. 3, pp. 217–223, 2020.

[5] T. J. Zuber, “Minimal excision technique for epidermoid (sebaceous) cysts,” Am. Fam. Physician, vol. 65, no. 7, pp. 1409–1412, 2002.

[6] S. W. Park et al., “A demographic study of cutaneous cysts in a large cohort of patients: 10-year experience,” J. Am. Acad. Dermatol., vol. 80, no. 2, pp. 579–581, 2019.

[7] E. Half et al., “Hereditary colorectal cancer syndromes,” Curr. Opin. Gastroenterol., vol. 25, no. 1, pp. 49–55, 2009.

[8] N. Rajan and J. A. Langtry, “The CYLD cutaneous syndrome,” Br. J. Dermatol., vol. 180, no. 3, pp. 523–527, 2019.

[9] M. Nagarajan, “Pathogenesis of epidermoid cysts,” J. Cutan. Med., vol. 23, no. 4, pp. 345–347, 2019.

[10] H. Terui et al., “Molecular analysis of the content of epidermoid cysts,” J. Dermatol. Sci., vol. 82, no. 2, pp. 132–134, 2016.

[11] E. Calonje, T. Brenn, A. Lazar, and P. H. McKee, McKee’s Pathology of the Skin, 5th ed. Elsevier, 2020.

[12] H. K. Kim, “Sonographic features of epidermoid cysts in the head and neck,” J. Ultrasound Med., vol. 37, no. 5, pp. 1183–1189, 2018.

[13] L. Wang et al., “MRI characteristics of epidermoid cysts: A review of 30 cases,” Clin. Radiol., vol. 76, no. 4, pp. 315.e1–315.e7, 2021.

[14] T. J. Zuber, “Minimal excision technique for epidermoid (sebaceous) cysts,” Am. Fam. Physician, vol. 65, no. 7, pp. 1409–1412, 2002.

[15] N. Duhan et al., “Squamous cell carcinoma arising from an epidermoid cyst,” J. Cutan. Aesthet. Surg., vol. 4, no. 3, pp. 211–213, 2011.

[16] J. Sterling, Intralesional Corticosteroid Injections, in Dermatologic Surgery. New York, NY: McGraw-Hill, 2018.

[17] M. Alam and L. H. Goldberg, “A comparison of two methods of cyst excision,” Dermatol. Surg., vol. 30, no. 6, pp. 922–924, 2004.