D03.7

Clinical Causes: Excessive exposure to ultraviolet (UV) radiation from sunlight or tanning beds. Having a fair skin complexion, which offers less natural protection against UV rays. A history of sunburns, especially severe or repeated episodes during childhood or adolescence. Family history of melanoma or other skin cancers. Presence of numerous moles or atypical moles on the skin. Previous skin injuries or burns that may have caused cellular damage. Use of immunosuppressive medications or conditions that impair immune response.

Key Symptoms: The appearance of new or changing pigmented lesions on the skin. A mole that changes in size, shape, or color over time. Lesions with irregular borders or uneven color distribution, including shades of black, brown, and tan. Lesions that are asymmetrical, with uneven edges. Itching, tenderness, or bleeding in the affected area, although these are less common in early stages. Presence of a flat, pigmented patch that has recently expanded or altered.

Diagnosis Path: Diagnosing melanoma in situ involves a comprehensive clinical examination of the skin, focusing on suspicious pigmented lesions. Dermatologists may employ tools like dermoscopy to analyze skin features in detail. When a lesion appears concerning, a biopsy is performed—typically a shave, punch, or excisional biopsy—to obtain tissue samples for pathological examination. Histological analysis confirms whether abnormal melanocytes are confined to the epidermis, warranting the diagnosis of melanoma in situ. Additional tests can include lymph node assessment if invasive components are suspected, but in melanoma in situ, these are generally not necessary.

Treatment Protocols: The primary treatment for melanoma in situ of the lower limb is surgical excision. The goal is to remove all abnormal cells completely while conserving healthy tissue. The procedure usually involves excising the lesion with a safety margin of healthy skin tissue to ensure complete removal. Depending on the lesion's size and location, procedures such as Mohs micrographic surgery may be employed for optimal tissue conservation and precise removal. Follow-up care involves monitoring the excision site for signs of recurrence and conducting regular skin examinations to detect any new lesions early. In some cases, additional treatments like topical therapies or immunotherapies are considered if the lesion cannot be fully excised or if it recurs.