Development of Six Tumors in a Sebaceus Nevus of Jadassohn: Report of a Case
A 70-year-old woman presented to our outpatient clinic with a verrucous growth on her scalp measuring 2.5×1.8 cm. The lesion presented at birth. While she was unaware of any specific changes in the lesion for decades, she noticed a rapid progression in the last two years. She was generally healthy and had no accompanying symptoms. The patient had no previous history of cutaneous or internal malignancies and a complete systems review was negative. There was no family history of malignancy.\nThe lesion of NS was completely excised with a free margin of 0.2 cm and submitted for histopathological evaluation. Macroscopic examination of the lesion revealed a 2.5×1.8 cm, yellowish, verrucous plaque devoid of hair. One large, vegetative plaque with a hemorrhagic crust lay within the yellowish plaque.\nHistopathological findings of the lesion by hematoxylin and eosin staining showed acanthosis, papillomatosis, sebaceus gland hyperplasia, and immature hair follicles in the dermis in the peripheral parts of the lesion. These findings were consistent with a diagnosis of NS. In addition, there were 6 adnexal tumors in the lesion including SCAP, PT, TAA, sebaceoma, TFI, and superficial epithelioma with sebaceus differentiation (SESD). The majority of the lesion was composed of SCAP, PT, and TAA. The tumors were separated from each other by loose fibrillary connective tissue stroma. These benign tumors were partly intertwined (, ).\nCytomorphologically, the SCAP was composed of irregular papillary projections covered by double layers of epithelium and stratified squamous epithelium with stroma containing lymphocytes and large numbers of plasma cells (). The deeper portion of the SCAP consisted of tubular structures with two layers of epithelial cells. While the luminal cells of the tubules were columnar and showed decapitation secretion, the outer layer was composed of flattened cells. These tubules were surrounded by a fibrous stroma. TAA was diagnosed from these findings ().\nThe PT was characterized by a well-circumscribed large basaloid dermal tumor without an epidermal connection. There were dispersedly brown pigmentation fields in the center of large tumor islands ().\nIn our case, small foci of follicular infundibulum, sebaceoma and SESD were observed. The TFI was composed of a plate like growth of basaloid keratinocytes with several points of attachment to the epidermis (). A collection of benign basaloid sebaceus cells suggestive of a sebaceoma was present and the sebaceoma existed as two types: superficial and deep in the dermis. There were cysts containing debris from holocrine degeneration (). The SESD was characterized by a sharply defined and well-circumscribed plate-like epidermal growth. Merging with the superficial keratinocytes was a cytologically bland basaloid cell population in which admixed mature sebocytes were present in clusters ().