Pilomatricoma: causes, symptoms, diagnosis, treatment

Pilocimacoma (synonymous necrotizing calcified malerb epithelioma) occurs more often in childhood and adolescence, mostly on the face or in the shoulder region, in the form of a solitary tumor reaching a few centimeters, covered more often by normal skin with a smooth surface protruding above the skin, very dense consistency. It grows slowly over the years, does not ulcerate. Sometimes family cases are observed.

Pathomorphology of the pyloricarcoma. A characteristic feature of pyloric coma at early stages of development is the presence of massive layers of small rounded cells with dark basophilic nuclei and an almost indistinguishable cytoplasm - typical cells of the hair matrix. Within these clusters, we see islands of gradual transformation of matrix cells into larger cells with a pale-colored cytoplasm with fuzzy boundaries and pycnotic, gradually disappearing nuclei, resulting in them being called shadow cells. Stroma of the tumor in the first stages is rich in blood vessels. In more mature formations, accumulation of shadow cells is observed, the vascular component is poorly expressed, the processes of dystrophy with the presence of giant multinucleated macrophages and deposits of calcium salts that are in the form of small granular masses are found in shadow cells or are located in the form of amorphous masses revealed by the method of Cossa In 15-20% of cases ossification is observed. Among the dystrophic islets of pale-colored cells, clusters of immature keratin, as well as pigmented cells of the hair bulb, are often found. Sometimes the pyloricarcoma may appear in the wall of the hairy cyst.

Histology of the pyloricarcoma. Histochemical examination and electron microscopy revealed that basaloid cells are cells of an immature hair matrix. A sharply positive reaction to SS- and SH-groups in most tumor cells and double refraction of shadow cells in a polarization microscope indicate a tendency of tumor cells to keratinize. The transition cellular elements between matrix cells and shadow cells are analogous to those in normal keratinization of the hair, they contain a large amount of tonofibrils and there is no keratohialin keratinization stage.

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