Eray Yihui Zhou

Objective: Physical treatment modalities, such as ablative fractional laser (AFL), electrocautery, and cryotherapy, are extensively used in the field of dermatology. This study aimed to characterize the short‐term innate and adaptive immune responses induced by AFL compared with heat‐ and cold‐based procedures.Materials and Methods: Innate (CD11b⁺Ly6G⁺ neutrophils) and adaptive (CD8⁺CD3⁺ T cells) immune cell infiltration and histopathological changes were examined in murine skin on Days 1 and 7, following AFL, monopolar‐electrocautery (RF), thermocautery, and cryotherapy. Interventions were standardized to reach the reticular dermis. Clinical skin reactions were photo‐documented daily. As a comparator, the adaptive immune response was examined in murine basal cell carcinomas (BCC) on Day 7 after AFL exposure.Results: Baseline histopathology confirmed immediate deep dermal tissue impact by all procedures. Immune cell dynamics varied across treatments throughout the progression of clinical and histopathological responses. On Day 1, AFL and heat‐based procedures triggered an innate immune response, characterized by CD11b⁺Ly6G⁺ neutrophil cell infiltration that correlated with histopathological findings and immediate onset of clinical skin reactions. In addition, heat‐based procedures led to an increase in overall dermal CD45⁺ cells (Day 1), which continued to rise for AFL and RF‐electrocautery at Day 7 posttreatment. On the contrary, cryotherapy did not induce immediate (Day 1) innate immune responses, but instead a delayed increase in neutrophil and CD45⁺ cell infiltration (Day 7), which coincided with the late onset of clinical reaction. CD3⁺ T cells and CD8⁺CD3⁺ T cells demonstrated a similar pattern, with an increase observed for heat‐based procedures on Day 1 and a delayed increase for cryotherapy on Day 7. Distinctive for AFL‐treated skin, the level of dermal CD3⁺ T cells increased over time, significant by Day 7, and AFL‐treated mouse BCCs responded with increased CD8⁺ T cell infiltration at Day 7 posttreatment.Conclusion: Heat‐ and cold‐based procedures developed distinct cutaneous immune responses, with cryotherapy resulting in a delayed response compared to immediate immune responses from heat‐based procedures. The substantial T cell response induced by AFL in the skin and BCC tumors indicates a potential for AFL as an adjuvant in immunotherapeutic treatments of keratinocyte cancers.

Background Epidermoid cyst (EC) is a common and benign tumor, which can occur anywhere on the skin. Surgical excision is usually considered as the first‐line treatment. However, linear scars arising after excision for EC remain a cosmetic problem. Objective To evaluate the efficacy and safety of EC removal assisted with CO₂ laser fenestration. Methods All patients diagnosed with EC and treated with CO₂ laser fenestration, content extrusion, and removal of the cyst wall between January 1, 2016, and December 31, 2018, were included in this study. After a follow‐up period ranging from 6 to 27 months, scarring, recurrence, complications, and satisfaction were assessed and analyzed. Results Forty‐three of the 47 patients have been cured by a single operation. The recurrence rate was 8.5%, which was not significantly correlated with tumor sizes or locations. 46.8% of the patients had no obvious scar after treatment. No infections or complications were observed in any of these cases. 89.4% of the patients were satisfied with the effectiveness of the treatment, while 95.7% and 87.2% were satisfied with the comfort and the cosmetic results, respectively. Conclusions CO₂ laser fenestration‐assisted removal procedure is effective for the treatment of ECs with good aesthetic outcome.

A young woman presented with multiple arciform to annular plaques on her extremities, favoring the antecubital and popliteal fossae (Figure, A). The patient reported that these asymptomatic lesions had been present since her adolescence, and she was easily bruised with minimal trauma since birth. There was no family history of similar cutaneous findings. On close inspection, the plaques were found to be composed of individual 2- to 4-mm keratotic papules surrounding white atrophic patches. Physical examination also revealed remarkable skin atrophy on the dorsal aspects of her hands (Figure, B) and feet. The patient’s skin was generally pale and translucent with visible veins, especially on the chest and abdomen. The face appeared to be emaciated, with a pinched nose, thin lips, sunken cheeks, and prominent eyes. A punch biopsy specimen from an individual papule from the left arm was obtained and analyzed under Verhoeff–van Gieson stain (Figure, C).

Xeroderma pigmentosum (XP) is a rare genetic disorder which is divided into eight complementation groups: XP‐A to XP‐G and XP‐V. Some XP patients demonstrate severe cutaneous and neurological manifestations, management of which requires timely diagnosis and intervention. We performed clinical evaluation and genetic analysis on 19 patients, the largest cohort of XP to date in China. Twenty‐three mutations from six groups were identified, 16 of which were novel. All patients developed marked freckle‐like pigmentation on sun‐exposed sites while patients with XP‐A, XP‐D, XP‐F and XP‐G showed acute sunburn reactions. Only XP‐A patients displayed progressive neurological degeneration. A relatively larger proportion of XP‐A and XP‐C were found in Chinese XP patients. One XP case and two carriers were prenatally determined. This study extended the mutation spectrum of XP in China and may aid in the diagnosis and treatment of Chinese XP patients.