Cystic epithelioma: causes, symptoms, diagnosis, treatment

Cystic epithelioma (syn: proliferating trichylemal cyst, pilar tumor) is a fairly rare tumor, mainly occurring in individuals older than 40 years, although the age range is quite wide - from 26 to 87 years. In women, the tumor occurs twice as often as in men. It is localized mainly on the scalp, less often on the face and trunk, the elements are usually solitary. In the early stages, this is a fairly clearly delimited intradermal nodule, displaced, dense-elastic consistency, as the beginner grows above the level of the surrounding skin. Long-existing formations can reach large sizes - 10 cm or more, forming express sites on a wide base of the bizarre configuration due to uneven growth of the tumor. A direct clinical diagnosis is usually limited to some kind of cyst - the sebaceous, the hairy, the epidermal.

Pathomorphology of cystic epithelioma. The basis of the neoplasm is a cyst of various sizes, located in the dermis, sometimes closely associated with the epithelium of the enlarged and elongated follicular funnel. From the epithelial lining of the cyst, strata of proliferating keratinocytes of various sizes and configurations forming solid and cystlike structures can depart. Complexes consist of basal and prickly layers containing keratinocytes with abundant pinkish cytoplasm, fuzzy intercellular bridges. Cells of granular type are absent. Sometimes in solid complexes the processes of dyskeratosis, nuclear atypia, mitotic activity are expressed. Cystlike structures have a wall reminiscent of the epithelial lining of the follicle in the isthmus zone and are filled with compact (homogeneous) keratin in the central part. In case of damage, granulomatous type inflammation, the appearance of extravasates of erythrocytes, a variety of siderophages may occur.

The greatest difficulties in differential diagnostics with squamous cell carcinoma can cause areas of cystic epithelioma with the phenomena of dyskeratosis, atypia and mitotic activity. In squamous cell carcinoma, these phenomena are much more pronounced, in addition, evaluation of the tumor configuration at low magnification can help in differential diagnosis - clear, smooth boundaries of the element are more characteristic of cystic epithelioma.

[1], [2], [3], [4], [5]