Cutaneous leiomyosarcoma is a rare malignant tumor that arises from the smooth muscle cells in the skin, specifically the piloerector muscles, which are located in the skin and eyes. This type of cancer typically presents as a firm, painless nodule or mass on the skin and can occur anywhere on the body. It is diagnosed by biopsy and is treated by surgical excision. Early diagnosis and treatment are crucial to prevent metastasis and improve prognosis.