High Risk of Non-Melanoma Skin Cancer in Actinic Keratosis Patients with Skin of Color: A Nationwide Register-Based Cohort Study.

INTRODUCTION: Actinic keratoses (AK) are rough, scaly patches from UV exposure, increasing the risk of non-melanoma skin cancer (NMSC). This study examines AK incidence in Korea and its role as a risk factor for NMSC. METHODS: A retrospective nationwide register-based cohort study analyzed 2,917 AK patients and 14,585 controls from 2002 to 2019. Patients diagnosed with AK were followed until NMSC occurrence, death, emigration, or December 2019. RESULTS: AK incidence reached 44.8 per 100,000 person-years in 2019. The adjusted hazard ratio for NMSC in AK patients was 8.91 (95% confidence interval, 5.72-13.90). Higher NMSC risk was observed in female AK patients, those under 60 years, and those with lower income levels. The 16-year cumulative incidence of NMSC was 4.19% in AK patients versus 0.44% in controls. CONCLUSION: AK significantly increases the risk of NMSC in Koreans, highlighting the need for tailored surveillance and treatment strategies.

A novel nerve block technique for nail surgery.

In pediatric patients, nail unit anesthesia is frequently required for procedures including matrixectomy or nail avulsion. However, nail unit anesthesia is very painful and requires a significant amount of time to take complete effect, causing a great deal of distress for most pediatric patients. By targeting the palmar and dorsal digital nerves in the distal part of the fingers, our method enables fast, simple, and less painful anesthesia.

Histopathological differences between vitiligo and lichen sclerosus et atrophicus using quantitative immunohistochemical analysis.

Introduction: Lichen sclerosus et atrophicus (LS) is rare skin condition characterized by the presence of whitish patches primarily affecting the genital and perianal areas, though it can occur other parts of the body. LS may result in skin depigmentation without textural changes and should be differentiated from vitiligo. However, the histopathological features of hypopigmentation during vitiligo and LS have rarely been compared and have not been precisely described using quantitative immunohistochemical analysis. This study, therefore, aimed to investigate and compare the pigmentary characteristics of LS and vitiligo lesions using histochemical and immunohistochemical staining. Methods: We included 31 and 46 patients diagnosed with LS and vitiligo, respectively, at Ajou University Hospital between March 2009 and March 2020 in this study. Their medical charts and skin biopsy specimens were retrospectively reviewed. Additionally, Fontana-Masson staining for melanin and immunohistochemical staining for Melan-A, NKI/beteb, tyrosinase, and microphthalmia-associated transcription factor was performed. Results: The melanin content, as well as the number of melanocytes was, in general, significantly higher in the epidermis of patients in the LS group compared with that in the vitiligo group. However, 22.6% of LS tissues showed less melanin pigmentation, 25.8% of LS specimens exhibited a lower number of melanocytes, and 29.0% of LS specimens demonstrated less melanocyte activity when compared with the average of vitiligo specimens. Conclusion: As lower melanin pigmentation and the near absence number of melanocytes were also observed in several LS specimens, both the clinical and histological findings must be comprehensively reviewed to differentiate vitiligo from LS.