An acanthoma is a skin neoplasm composed of squamous or epidermal cells. It is located in the prickle cell

Prickle cell

A prickle cell is an epidermal cell which lies above the basal cell layer, constituting a stratum spinosum, which forms innumerable intercellular bridges. These intercellular bridges give the stratum spinosum a rough appearance to which the cells of which it is composed owe their name...

 layer.

Types of acanthoma include pilar sheath acanthoma, a benign follicular tumor usually of the upper lip; clear cell acanthoma, a benign tumor found most frequently on the legs; and Degos acanthoma, often confused with but unrelated to Degos disease

Degos disease

Degos disease is an extremely rare vasculopathy that affects the lining of the medium and small veins and arteries, resulting in occlusion and tissue infarction....

.

History

In 2005, "Acanthoma" was added to MeSH

Medical Subject Headings

Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it can also serve as a thesaurus that facilitates searching...

 as an index term; previous indexing was "Skin Neoplasms" (1965-2004). At that time, PubMed

PubMed

PubMed is a free database accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintains the database as part of the Entrez information retrieval system...

indexed only 206 articles with the term "acanthoma" (the term usually in the title or abstract).