1临床资料患者女,71岁。头皮出现皮疹伴瘙痒2年。2年前无明显诱因患者左侧顶部头皮出现黄豆大丘疹,伴瘙痒,正常肤色,无疼痛。近2年来,皮疹略增大,1周前瘙痒加重。既往体健,家族中无类似患者。系统检查未见异常。皮肤科情况:左侧顶部头皮可见一孤立的黄豆大丘疹,正常肤色,质硬,表面粗糙,顶端可见角栓(图1)。皮损组织病理示:表皮角化过度,中央呈 1 Clinical data Female patient, 71 years old. Scalp rash with itching 2 years. 2 years ago no obvious incentive to appear on the left side of the top of the scalp soy papules, with itching, normal skin tone, no pain. The past two years, the rash slightly increased, itching increased 1 week ago. Past physical health, no similar family in patients. No abnormal system check. Dermatology: The left top of the scalp can be seen isolated soybean papules, normal skin tone, hard, rough surface, the top corner plug can be seen (Figure 1). Pathological lesions showed: epidermal hyperkeratosis, the central was