It was in 1980 that Rothko et al. introduced the term "superficial epithelioma with sebaceous differentiation" for lesions encountered in just one patient over a period of eight years. The authors described plate-like aggregations of basophilic cells with broad attachment to the overlying epidermis together with keratin cysts and sebaceous cells within the lobules. The lesions have situated on the face, axilla, trunk, and thigh. Photomicrographs of only three lesions were shown in the article (Figs. 1A-C). [1]

Seven years later, Friedman and colleagues made the diagnosis of superficial epithelioma with sebaceous differentiation in 5 patients, in all of whom the lesions had developed as solitary papules on the face.[2] All lesions were described as having a plate-like arrangement of basaloid and squamoid cells together with sebacoeus differentiation. The authors considered the lesions diagnosed by them to be the same described by Rothko et al. previously. Only three lesions were shown in photomicrographs (Figs. 2A-C).

Vaughan, in 1990, reported on a lesion diagnosed by him as superficial epithelioma with sebaceous differentiation (Fig. 3). [3] A longstanding asymptomatic yellowish plaque from the back histologically showed numerous sebaceous lobules connected to surface epidermis. Lobules were made up of mature and immature sebocytes.

A unique lesion was described in 1992 by Sachez-Yus et al. (Figs. 4A-B). [4] In a longstanding plaque on the buttock area of a 60-year-old man developed into a squamous cell carcinoma, a poorly differentiated adenocarcinoma, and a neoplasm of trichoblastic differentiation. The plaque was made up of partly reticulated epithelial proliferations consisting of mature and immature sebocytes. The proliferations were connected to surface epidermis. The authors diagnosed this plaque as superficial epithelioma with sebaceous differentiation.

Kato and Ueno told of their experience with a patient who developed a small yellow plaque on the eyelid (Fig. 5). Histologically, the lesion was multilobular with numerous broad attachments to the overlying epidermis made up of uniform basaloid cells with single or clustered sebocytes in the upper part of the tumor and multiple well-differentiated sebaceous lobules in the middle and lower parts of the tumor. Multiple cystic spaces were formed in the lobules. [5] A reticulated pattern of the aggregations was not emphasized by the authors.

In 1994, in a textbook titled Neoplasms with Sebaceous Differentiation, Steffen and Ackerman analyzed critically all lesions published with the diagnosis superficial epithelioma with sebaceous differentiation. [6] In their opinion, the lesions described by Rothko et al. were not the same as published by Friedman et al. They reproduced photomicrographs of the lesions of the article by Rothko et al. and rediagnosed two of them as seborrheic keratoses with sebaceous differentiation and one as a verruca vulgaris with sebaceous differentiation. After reassessing the article by Friedman et al. Steffen and Ackerman came to the conclusion that one of the cases was better diagnosed as a verruca vulgaris with sebaceous differentiation, while two other cases pictured shared a superficial plate-like and reticulated arrangement of cells with sebaceous differentiation. The lesion presented by Sanchez-Yuz et al. was also reassessed by the authors, who concluded that the lesion was similar to those described by Friedman et al. Steffen and Ackerman considered the reticulated arrangement to be a highly distinctive feature of all these lesions and proposed the name "reticulated acanthoma with sebaceous differentiation" for the condition which they deemed to be unique. Steffen and Ackerman added 5 lesions from their own experience which they had diagnosed as reticulated acanthoma with sebaceous differentiation (Figs. 6- 10). They claimed that the neoplasm had two different presentations, namely, plaque-like and exophytic pedunculating, for both of which they gave examples.

Akasaka and colleagues published in 1994 a report of a patient in whom they had diagnosed a superficial epithelioma with sebaceous differentiation on the left cheek. Histopathology demonstrated plate-like lobules of basophilic basaloid cells with broad attachments to the overlying epidermis (Fig. 11). [7] The lesion was relatively compact and reminiscent of the first one pictured in the article of Rothko et al. A reticulated pattern was not present.

In 2003, Lee and colleagues reported on a patient in whom they had made the diagnosis of superficial epithelioma with sebaceous differentiation. [8] The lesion was situated on the back and consisted of a brownish plaque. Histologically, the lesion showed a plate-like arrangement of proliferations with sebaceous differentiation and a few cysts filled with keratin (Fig. 12). A reticulated pattern of the aggregations was not pictured in the photomicrographs included in the publication.

In 2006, Fukai and coworkers told of a patient diagnosed with reticulated acanthoma with sebaceous differentiation. [9] The lesion was a longstanding pink-to-brown patch on the upper back of a 55-year-old woman. On histopathology, the lesion showed a reticulated pattern of epithelial strands and exhibited sebaceous differentiation at the lower parts of them (Figs. 13A-D). The authors excluded the differential diagnosis of a seborrheic keratosis with sebaceous differentiation because infundibular cysts and basal pigmentation were not encountered in the lesion.

In the textbook Histopathologic Diagnosis of Adnexal Epithelial Neoplasms, Böer and Ackerman, in 2008, presented reticulated acanthoma with sebaceous differentiation as a distinct entity. [10] They emphasized the reticulated arrangement of strands of epithelial cells with sebacoues differentiation, occasionally forming chains. The examples given in photomicrographs were the same as shown in the previous textbook on neoplasms with sebaceous differentiation, reproduced here as Figures 6 and 7. [6] In their opinion, the differential diagnoses to be considered were seborrheic keratosis with sebacoeus differentiation and verruca vulgaris with sebaceous differentiation, both being identifiable mainly based on silhouette.

In a new edition of the textbook titled Neoplasms with Sebaceous Differentiation, published only recently, Ackerman and coworkers addressed, once again, the subject of reticulated acanthoma with sebaceous differentiation. They continued the review of the literature from the previous edition and commented on the lesions published by Kato and Ueno, by Akasaka et al., and by Lee et al. Ackerman et al. insisted that reticulated acanthoma with sebaceous differentiation is a distinctive neoplasm that may present as a plaque or as a pedunculating lesion. They considered the reticulated architecture the most important finding and provided a set of criteria that was thought by them to enable differentiation of reticulated acanthoma with sebaceous differentiation from seborrheic keratosis with sebaceous differentiation and from verruca vulgaris with sebaceous differentiation. The illustrations given by the authors are the same as shown in the volume of 1994. In contrast to the previous edition, however, no photomicrographs from articles reviewed were reproduced in the chapter.