Epidermolytic Hyperkeratosis in Nevi

Abstract

Epidermolytic hyperkeratosis (EH) has been described as a reaction pattern in a variety of solitary skin lesions. We have noted that EH seems to occur more frequently in association with atypical than with typical acquired nevi. To support or refute this observation, the prevalence of EH in 250 cases of atypical compound nevi and in 250 cases of typical compound nevi was determined. EH was identified in 10 cases of atypical compound nevi and in two cases of typical compound nevi, which is a statistically significant difference with p value < 0.02. Since EH occurred in only 4% of atypical nevi examined, it should not be considered a diagnostic criterion. However, the identification of EH in otherwise histologically typical nevi should prompt the pathologist to make sure the lesion has been adequately sampled.

Histopathologic characterization of epidermolytic hyperkeratosis: A systematic review of histology from the National Registry for Ichthyosis and Related Skin Disorders

“…It should be noted that these same histopathologic features of hEHK are seen in a variety of other conditions including epidermolytic acanthoma and nevoid follicular epidermolytic hyperkeratosis 3, 4. EHK histology has been reported as an incidental finding in a large variety of conditions including melanocytic nevus, solar keratosis, squamous cell carcinoma, basal cell carcinoma, pilar cyst, seborrheic keratosis, cutaneous horn, skin tag, both oral and genital mucosal leukoplakia, nevus comedonicus, and progressive systemic sclerosis 5–14. It has also been seen incidentally in normal skin and in normal oral mucosa 15…”

Incidental Cutaneous Reaction Patterns: Epidermolytic Hyperkeratosis, Acantholytic Dyskeratosis, and Hailey-Hailey-Like Acantholysis: A Potential Marker of Premalignant Skin Change

“…This was confirmed in a follow-up study [6], although the association was of limited utility, given a low sensitivity, with only 4% of atypical nevi showing incidental EHK [5]. A follow-up study however failed to identify this association but did identify one between incidental FAD and dysplastic nevi [4].…”

“…Incidental EHK has been reported to be a useful marker when present for dysplastic nevus, being found more commonly in or around nevi with architectural disorder than in common melanocytic nevi [5]. This was confirmed in a follow-up study [6], although the association was of limited utility, given a low sensitivity, with only 4% of atypical nevi showing incidental EHK [5].…”

Epidermolytic hyperkeratosis within infundibular cysts

“…On the other hand, incidental EH may not be incidental at all and may reflect underlying mechanisms that similarly contribute to the processes going on in adjacent tissue. Recent studies have shown that EH is more commonly associated with atypical than typical nevi 7,11 and may be a marker for nevi with architectual disorder vs. ordinary melanocytic nevi. Such findings support the theory that EH may not be just a random finding.…”

“…Since 1970, when Ackerman 6 first proposed the idea of incidental EH, many reports of EH have been published including that in association with varied nevi, 7–11 squamous cell carcinoma, 6,12,13 basal cell carcinoma, 8,13 melanoma, 8 epidermolytic acanthoma, 8 seborrheic keratosis, 6,8 scar, 8,14 leukoplakia, 15 and nevus comedonicus 16 . Although EH can be found repeatedly in the literature in association with a number of lesions, it has not been described in association with an infundibular cyst since a report by Mehregan 14 in 1978, which was the first as well as last published report.…”