The Relationship of Molluscum Sebaceum (Keratoacanthoma) to Spontaneously Healing Epithelioma of the Skin

Abstract

THERE is an astonishing neglect in the literature of the benign cutaneous condition described by MacCormac and Scarff in 1936, and named by them molluscum sebaceum. An alternative name, kerato-acanthoma, has since been applied, and this has the merit of preventing confusion with molluscum contagiosum, an unrelated condition. It has been the subject of only 4 papers, all by British authors, MacCormac and Scarff (1936), Musso and Gordon (1950), Rook and Whimster (1950) and Beare (1953), and does not yet appear to have reached text-books of dermatology or pathology. That this in no way reflects the incidence of molluscum sebaceum is certain. Indeed, it is not an uncommon condition, and is still very frequently misdiagnosed as squamous-cell carcinoma by both dermatologist and pathologist.Smith, in 1934, described the occurrence in a young man of multiple primary squamous-cell carcinomas of the skin which healed spontaneously and he was unable to find any comparable case in the literature. Since that time there have been eight papers on the subject (Table II) with descriptions of similar lesions in 11 patients. Comparison of the clinical and pathological descriptions of these cases with the natural history and the structure of molluscum sebaceum at once suggests the probability that all the recorded cases of spontaneously healing epithelioma of the skin are in fact instances of molluscum sebaceum.The following account is based on a series of 7 cases of molluscum sebaceum which after biopsy diagnosis were untreated and allowed to run their natural course to spontaneous regression. Numerous other cases have been studied, but are not included here because they were treated by radiotherapy or surgery.Molluscum sebaceum.Clinical features.-Some of the clinical features of the lesions in our 7 cases are summarized in Table I.Histology.-The histological structure of molluscum sebaceum was admirably described and illustrated by Dunn and Smith (1934), though, unfortunately, under the diagnosis of " Self-healing primary squamous carcinoma of the skin." That they were not fully convinced of the correctness of the diagnosis is suggested by their statement that " It may be we are dealing with something which is not quite cancer in the ordinary accepted sense, but which cannot in its early stages be * Medical Research Council Scholar.

Multiple Self-Healing Epithelioma of Ferguson Smith Type

“…Other authors (Whittle and Lyell, 1952;Fouracres and Whittick, 1953;Marshall and Findlay, 1953;Marshall and Pepler, 1954) Dupont (1954) in five cases and by Huriez and coworkers (1954) and by Vaccari and Tagliavini (1955) in single cases. The keratoacanthoma is usually solitary, but not necessarily so (Allington, 1955;Whittle and Lyell, 1952;Binkley and John¬ son, 1955), and the number of lesions provides no valid criterion for the differen¬ tiation of the two conditions.…”

“…However, in those more re¬ cently reported cases (Rabut and Hewitt, 1954;Puente Duany, 1954) typical lesions developed on the vermilion border of the lips, and this hypothesis is therefore not universally applicable. Fouracres and Whittick (1953) believed that the self-healing epithelioma was of in¬ fective origin and that increased opportuni¬ ties for spread of the infection within a family could explain the apparently heredi¬ tary incidence. Ereaux and co-workers (1955) succeeded in isolating a virus from one case.…”

Multiple Primary Self-Healing Squamous-Cell ``Epitheliomas'' of the Skin

“…The first case which he reported was that of a young man, aged 23, a coal miner, on whom, since the age of 16, multiple tumors of the face, ears, arms, thighs, and legs had developed. They began as red macules, then became papular, and enlarged to become raised tumors which ulcerated and ultimately healed, leaving pitted or smooth scars.…”

The Multiple Growth of Molluscum Sebaceum in Donor and Recipient Sites of Skin Graft

“…As the features of molluscum sebaceum have recently been described by Beare (1953 1 and by Fouracres and Whittick (1953) it will not be necessary to enter upon a general description of the disease here. Fouracres and Whittick have pointed out the probable identity of molluscum sebaceum and multiple self-healing squamous cell carcinoma of the skin.…”