Keloid, also known as scar tumor, is a benign tumor caused by excessive proliferation of connective tissue after skin injury.

bubble_chart Etiology

Cause of disease: Scar constitution is a significant factor in the onset, which can occur spontaneously or result from excessive connective tissue proliferation following trauma or mechanical stimulation. A family history is often present, and some believe it is inherited as an autosomal dominant trait. It may also stem from foreign body reactions leading to connective tissue hyperplasia. Infections, surgeries, burns, insect bites, and other minor injuries can all trigger the development of idiopathic scars.

bubble_chart Clinical Manifestations

It is commonly seen in adults, predominantly on the upper chest, but can also affect the back, shoulders, and limbs. The lesions appear as irregular, firm, flat elevations with a dark red color, smooth and shiny surface, and absence of hair. They often exhibit telangiectasia or dendritic proliferation. The lesions may gradually enlarge and are accompanied by itching, pain, or a stinging sensation, with varying degrees of tenderness. Their shapes can be linear, circular, oval, or irregular, with variable sizes and well-defined borders. Surrounding the lesions, dilated capillaries may proliferate in a radial pattern. In a few patients, the lesions may soften, shrink, and flatten over time, eventually turning into soft atrophic scars. Lesions occurring near joints can lead to contractures and restricted movement. When affecting the face, they may cause disfigurement and difficulties in mouth and eye movement.

bubble_chart Prognosis

Prevention: Individuals with a keloid constitution should avoid trauma, surgery, and skin infections. Those with cutaneous pruritus may be given antipruritic agents. (1) Local treatment: A suspension of acetic acid prednisolone or triamcinolone acetonide mixed with an appropriate amount of 1% procaine solution can be injected into the lesion or its base once a week. (2) Radiotherapy: Both radium therapy and superficial X-ray irradiation yield excellent results. For cases requiring surgical excision, radiotherapy should be administered before and after the operation or postoperatively. Simple excision is contraindicated. (3) Physical therapy: Audio-frequency electrotherapy, iodine iontophoresis, or magnetotherapy may be used.