What is piloacanthoma?

We often encounter some diseases in life. We can ignore some minor problems, but there are many serious diseases that require timely treatment. There are still some diseases that we have rarely heard of and have never encountered before, so we are not very clear about the severity of the problem, such as what is pilocarcinoma? We rarely see this disease, but if we don’t understand some relevant information, we will be caught off guard if someone around us discovers this disease. So we need to understand.

Acanthoma of the hair sheath is a follicular tumor that differentiates into the terminal hair follicles, namely the infundibulum and isthmus (the infundibulum extends from the epidermis and is connected to the isthmus, both of which are part of the hair sheath). Histopathology: Large irregular branching cysts appear, which are different from the dilated holes. In areas with mild hyperplasia, such as the dilated holes, most tumor cells are lobed and clump together, radially invading the dermis and subcutaneous tissue from the cyst wall. In some areas, the tumor cells are arranged in a palisade-like manner around and contain different amounts of glycogen, thus resembling the outer root sheath epithelium.

The lesions grow rapidly, from a 1 mm macule or papule to a 25 mm hemispherical, dome-shaped, skin-colored nodule within 3 to 8 weeks. On the surface of the nodule, a smooth crater with a central angular plug can be seen. The lesions are smooth and shiny with clear boundaries from the surrounding areas, and capillaries can be seen on the surface. Atypical keratoacanthomas are common; some resemble seborrheic keratoses or benign acanthomas, while others have a nodular, proliferative appearance with crater-like depressions. Giant keratoacanthoma refers to a tumor with a diameter greater than 2 cm, often invading the nose and eyelids. Subungual keratoacanthoma is rare, tender, and destructive crater-like in the center, often causing damage to the terminal phalanx. The subungual lesion often does not regress naturally and causes underlying bone destruction in the early stages.

Radiographically it is characterized by a crescent-shaped osteolytic defect without sclerosis or periosteal reaction. Single keratoacanthoma occurs most often on sun-exposed areas, such as the midface, back of the hands, and arms, but other areas such as the buttocks, thighs, penis, ears, and head may also be affected. In women, lesions are less common on the back of the hands, more common on the lower legs, and rare on the oral mucosa. It is more common in middle-aged and elderly people and less common in men. The interesting feature of this disease is that it takes about 2 to 6 weeks for rapid growth, then remains stable for 2 to 6 weeks, and finally disappears on its own after 2 to 6 weeks, leaving a mild depressed scar. However, some damage may take 6 months to 1 year to completely disappear. It is estimated that approximately 5% of lesions recur.

The above content is about what piloacanthoma is. After understanding it, we know that men can also develop this disease, and it is more serious, especially for older people, so they need to pay attention to prevention in their daily lives. Because the problem of tumors cannot be ignored and can seriously endanger life safety. Therefore, we should pay more attention to our behavior and diet structure.