Eczema-like carcinoma, also known as Paget’s disease, is a specific type of skin tumor that clinically manifests as eczema-like lesions and is characterized by large, lightly stained abnormal cells in the epidermis. The etiology and pathogenesis of eczema-like carcinoma are unknown. It is believed that it originates from in situ carcinoma in the ducts of the breast and the opening part of the parietal sweat ducts, and from there it expands down along the ducts of the breast and the glandular epithelium, and eventually invades the connective tissue; upward it expands into the epidermis and forms Paget’s disease lesions. Clinical manifestations of eczema-like carcinoma 1. Paget disease of the breast almost always involves women, mostly in the unilateral breast and areola, with an average age of onset of 55 years, rarely in male breast. The lesions start as scaly erythematous plaques or plaques, often accompanied by eczema words, superficial vesicles, oozing or crusting, infiltration is obvious, slowly expanding to the periphery, ulcers and nipple retraction can be formed. It is often accompanied by breast cancer and may have axillary lymph node metastasis. Extramammary Paget’s disease can involve both sexes, but is predominantly female, with an average age of onset greater than that of breast Paget’s disease. It is more common in the female pubic area, followed by the scrotum, perineum and perianal area, and is also seen in the parietal sweat gland area outside the pubic area (such as the axilla). The lesions are similar to breast Paget’s disease, but they are larger in size and appear as well-defined red patches or plaques, indicating eczema-like, erosion, oozing and crusting, with long painful itching. The prognosis is generally better than that of breast Paget disease, but it can be accompanied by intradermal invasive carcinoma; those who extend from rectal adenocarcinoma to perianal skin or from cervical cancer to vulva are called secondary extramamammary Paget disease and have poor prognosis. Histopathological examination of eczema-like carcinoma Single or nest-like arrangement of Paget cells in the epidermis, large cytosol, round or oval, no intercellular bridges, cells containing a large nucleus, abundant and lightly stained cytoplasm, even vacuolated, positive PAS reaction, resistant to amylase; Paget cells increase when the section extrudes surrounding cells into a network, and also extrudes the epidermal basement membrane band into a fine line, and the dermis is accompanied by chronic inflammatory cell infiltration in the dermis. The diagnosis and differential diagnosis of eczema-like carcinoma The occurrence of eczema-like patches in unilateral breast or parietal sweat gland distribution area in middle-aged and elderly people, with infiltration at the base, slow course and persistence, if treatment according to eczema is ineffective, the disease should be suspected, and pathological biopsy can confirm the diagnosis. This disease should be differentiated from breast, vulvar eczema, Bowen’s disease, basal cell epithelioma, etc. Treatment of eczema-like carcinoma Breast Paget disease should be treated with subtotal mastectomy or radical mastectomy if accompanied by intra-mammary masses. Extra-breast Paget disease should be treated by Mohs surgical technique with extensive deep excision to avoid recurrence. If the damage is large and involves the groin and perineum, implantation is required.