Background
Warty dyskeratoma (WD) is a benign epidermal proliferation first reported in 1957 because of its distinctive histologic findings.[1] WD presents as an umbilicated papule with a keratotic plug, usually limited to the head, neck, or face. Lesions are generally solitary and sporadic and may be associated with a follicular unit. Oral involvement,[2, 3] particularly the hard palate, eyelid,[4] and genital involvement have been reported.[5] Multiple lesions may occur in the same patient.[6, 7, 8, 9]
Although originally referred to as isolated keratosis follicularis, no data support that patients with a WD bear germline mutations in ATP2A2, the gene responsible for Darier disease. Patients with Darier disease have been reported with WDs occurring spontaneously or during treatment with systemic retinoids.[10]
Pathophysiology
Warty dyskeratoma (WD) represents a sporadic localized error in epithelial maturation and cohesiveness. James Fitzpatrick, MD, of Dermatopathology Consultants of Colorado, has shown using immunohistochemistry that these tumors lack SERCA2 thus providing evidence that an acquired genetic mutation in ATP2A2 plays a role in tumor development. Malunion and premature keratinization of epithelial cells occur. Attempts to demonstrate that human papillomavirus plays a role have proven unsuccessful.[11] Other adhesion molecules may also play a role.
Epidemiology
Frequency
Warty dyskeratoma (WD) is an uncommon lesion. Involvement of the mucosal surfaces is also uncommon.
Race
No racial predilection is known.
Sex
By a modest margin, warty dyskeratoma affects men more commonly than women.
Age
The average patient age at diagnosis for focal, oral warty dyskeratoma is 52.2 years; 10 of 13 reported patients were between the fifth and seventh decades of life.
Prognosis
There is no known risk of malignant transformation of warty dyskeratoma (WD). Recurrence after surgical removal is extremely uncommon. Although WD is histologically similar to Darier disease and appears to share the same absent protein (SERCA2) in at least some cases, no evidence indicates that patients with warty dyskeratoma are at risk for other disorders, including Darier disease.
Patient Education
Patients should be reassured that warty dyskeratoma (WD) is benign. While patients with Darier disease have been reported with WD,[12] the diagnosis of WD does not imply that the patient has Darier disease nor is at risk for transmitting Darier disease to offspring. Isolated WD is not associated with other systemic diseases and patients with a WD do not need routine follow-up in dermatology.
History
Warty dyskeratoma (WD) commonly presents as an asymptomatic keratotic nodule. Scalp, face, and neck are common sites of involvement. Mucosal lesions have been reported.[2, 3, 5] Multiple lesions in the same patient have been reported.[6, 7] Patients may report an insidious onset or a slight recent enlargement of the lesion.
Physical Examination
Warty dyskeratoma (WD) presents as a whitish or grayish hyperkeratotic papule with an umbilicated center, often involving the face, scalp, or back. Lesions are usually smaller than 1-2 cm.
Rarely, lesions with a similar appearance can be found involving the mucosal surfaces.[2, 3, 5] Infrequently, subungual warty dyskeratoma occurs and when it does it produces longitudinal erythronychia.[13, 14] Multiple lesions may occur in exceptional cases.[6, 7]
Causes
James Fitzpatrick, MD, of Dermatopathology Consultants of Colorado, has demonstrated using immunohistochemistry (unpublished work) that warty dyskeratoma demonstrates absence of SERCA2. This finding suggests that acquired genetic mutations in ATP2A2, as demonstrated by the absence of its protein product, SERCA2, play a role in the development of WD. See the image below.
View Image | Absence of sarco/endoplasmic reticulum Ca2+ ATPase 2 (SERCA2) staining by immunohistochemistry within a warty dyskeratoma (right side of image), in co.... |
To date, genetic evaluations of warty dyskeratoma (WD) for mutations in ATP2A2 (gene encoding SERCA2) have not been reported in the literature.
Two reports have demonstrated immunohistochemical staining of WD with antikeratin antibodies HKN-6 and HKN-7, and this reaction was interpreted as suggesting a follicular origin for WD.
Ultrastructural findings have been interpreted to suggest that acantholysis is due to a defect in desmosome-tonofilament complexes.
Epidermal viral infection with secondary hyperproliferation and acantholysis has also been proposed as a causative mechanism. However, a 2002 study showed that 13 of 13 cases did not show human papillomavirus DNA after polymerase chain reaction testing, and no data support a viral etiology at this time.[11]
Laboratory Studies
Because warty dyskeratoma (WD) has repeatedly been shown to be a lesion not associated with systemic disease, no laboratory studies are necessary.
Imaging Studies
No imaging studies are necessary.
Procedures
A biopsy specimen interpreted by a dermatopathologist is the criterion standard for diagnosis.
Histologic Findings
The pathologic process is that of a well-circumscribed endophytic or endo-exophytic epithelial proliferation of benign squamous cells demonstrating elongated dermal papillae (villi) with suprabasilar acantholysis and dyskeratosis. Dyskeratotic cells are referred to as corps ronds and grains. A central keratin-filled invagination may be identified. The lesion can sometimes be seen originating from a hair follicle or sebaceous gland.
View Image | Warty dyskeratoma. An endo-exophytic squamous proliferation of cytologically benign, acantholytic, and dyskeratotic keratinocytes. |
View Image | Villi lined by acantholytic keratinocytes, some of which are dyskeratotic (corps ronds and corps grains). |
Staging
Staging is not necessary for this benign lesion.
Medical Care
No medical care is required.
Surgical Care
Removal of the lesion by performing a punch biopsy or an excisional biopsy is an effective therapy for these benign lesions.
Diet
This benign process is unrelated to dietary influences.
Complications
The only complications associated with warty dyskeratoma (WD) are those associated with the minor surgical procedures required for the biopsy or the removal of these benign lesions.
Medication Summary
Medical therapy is not necessary for this benign lesion; it is cured with surgical removal.
Author
Molly Ann Allen Hinshaw, MD, Associate Professor, Department of Dermatology, University of Wisconsin School of Medicine and Public Health
Disclosure: Have a 5% or greater equity interest in: Accure Medical, I founded this company with two partners so have 33% interest in the company. We have spent our personal funds to start the company, have no products, and no income yet.
Specialty Editors
Richard P Vinson, MD, Assistant Clinical Professor, Department of Dermatology, Texas Tech University Health Sciences Center, Paul L Foster School of Medicine; Consulting Staff, Mountain View Dermatology, PA
Disclosure: Nothing to disclose.
Rosalie Elenitsas, MD, Herman Beerman Professor of Dermatology, University of Pennsylvania School of Medicine; Director, Penn Cutaneous Pathology Services, Department of Dermatology, University of Pennsylvania Health System
Disclosure: Received royalty from Lippincott Williams Wilkins for textbook editor.
Chief Editor
Dirk M Elston, MD, Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina College of Medicine
Disclosure: Nothing to disclose.
Additional Contributors
Timothy McCalmont, MD, Director, UCSF Dermatopathology Service, Professor of Clinical Pathology and Dermatology, Departments of Pathology and Dermatology, University of California at San Francisco; Editor-in-Chief, Journal of Cutaneous Pathology
Disclosure: Received consulting fee from Apsara for independent contractor.
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