Hyperplastic erythema

　　The etiology of hyperplastic erythema is unknown, it can occur spontaneously, but it often occurs in patients with poor healing and slight exudation after circumcision, caused by chronic irritation due to exudation. The mucosal epithelium is often involved in full thickness, with a clear boundary with the surrounding normal part, and its histological features are similar to those of skin in situ carcinoma. The histopathological characteristics are papillary epidermal acanthocytes hypertrophy, forming slender epidermal processes, resembling fingers growing downward to the dermis, but the basement membrane is intact, there is vascular dilation in the dermis, and lymphocytes and plasma cells present as zonal infiltration. Many atypical epithelial cells can be seen in the proliferating epithelium, with deeply stained nuclei or multinucleated nuclei. Tumor giant cells and dyskeratotic cells are less common.

　　The progression of hyperplastic erythema is slow, with a course of disease ranging from several months to 25 years, averaging about 2 years. If the duration is long, it presents as verrucous hyperplasia or ulceration, the complications of the disease are as follows.

　　1. Invasive squamous cell carcinoma: If non-invasive hyperplastic erythema is not treated in time or treated improperly, the lesions may appear infiltration, erosion, ulceration, or papillary changes, which often indicates the development of invasive squamous cell carcinoma.

　　2. Invasion of surrounding tissues and lymph node metastasis: Once it becomes invasive squamous cell carcinoma, it can invade surrounding tissues and be accompanied by regional lymph node and/or distant site metastasis (about 20%).

　　Hyperplastic erythema mainly occurs in patients with elongated prepuce who have not undergone circumcision, with an age range of 20 to 60 years. The lesions often occur on the glans, urethral orifice, coronal sulcus, and prepuce. Other mucosal sites such as oral mucosa, vulva, and anal mucosa may also be involved. Most cases are solitary, and the lesions usually manifest as a single clear, bright red or pale macular rash, some of which are slightly elevated, soft in texture, or with hard edges. They are round or irregular in shape, covered with shiny, difficult-to-peel grayish white scales. The diameter of the skin lesions is between 0.2 to 3.5 cm, averaging about 1 cm. Larger lesions can gradually expand from a single lesion or be formed by the fusion of multiple small lesions. Most of them are bright and slightly elevated macular rashes, or present as velvety plaques. If infiltration, erosion, ulceration, or papillomatous lesions occur, invasive squamous cell carcinoma changes are often found under the microscope. The disease progresses slowly, can remain unchanged for many years, and may develop into squamous cell carcinoma if not treated properly.

　　The etiology of proliferative erythema is unknown and can occur spontaneously. The prevention of proliferative erythema lies in avoiding any local irritation, paying attention to local cleanliness and hygiene. Pay attention to keeping the skin clean and dry, avoiding skin abrasions.

　　The histopathological examination of proliferative erythema shows thickening of the stratum corneum, covered with secreted crust or abnormal keratinous material. The epidermal cells are irregularly thickened, especially between the papillae at the edges, which can form epidermal processes extending into the dermis. The stratum spinosum is thickened, similar to Bowen's disease. The keratinocytes are纺锤 and elliptical, the cells can have large and heavily stained nuclei and multiple nuclei, and premature keratinization, polarity disorder, increased mitosis, and vacuolated cells may occur. Capillary dilation and inflammatory cell infiltration are observed in the dermis.

　　Patients with proliferative erythema should pay attention to a light diet, mainly with high-protein, high-vitamin, high-fiber, high-calorie, and low-fat diet, especially paying attention to food taboos. Some patients may experience allergic reactions after eating seafood, which may trigger or worsen the condition. Patients should also avoid smoking and drinking, as well as spicy and irritating foods.

　　Patients with proliferative erythema should avoid local irritation. Local excision, local cryotherapy, or photodynamic therapy can be performed surgically. External application of 5% to 20% fluorouracil cream is also possible, but attention should be paid to protect the scrotum, otherwise it is easy to cause edema due to irritation. The effect of superficial X-ray irradiation is good, usually using low voltage, generally using 29 to 43kV, 3000 to 5000R.