Linear lichen planus pigmentosus is a rare subtype of lichen planus pigmentosus that follows Blaschko’s lines, leaving long-standing residual atrophy and pigmentation, especially in dark-skinned populations. Conventional treatments have several limitations regarding the alleviation of pigmentation and atrophy. We report two cases of Korean women with linear lichen planus pigmentosus on their faces who were successfully treated with fractional lasers and intralesional injection of polydeoxyribonucleotide.

The effect of dupilumab on allergic contact dermatitis or patch testing is unknown. Here, we present a case of excited skin syndrome that appeared after patch testing during dupilumab treatment. A 21-year-old woman presented with atopic dermatitis that showed only a partial response to cyclosporine and dupilumab. A patch test was performed to check for underlying allergic contact dermatitis. The result was consistent with excited skin syndrome.Some studies argue that dupilumab suppresses allergic reactions triggered by allergens that activate the Th2 pathway. Others suggest that it does not affect the result of patch testing, regardless of the type of allergen tested. Even if dupilumab suppresses a certain allergic or immunologic pathway, this case shows that it cannot mask excited skin syndrome on patch testing.

Background: Upadacitinib is an oral Janus kinase1 (JAK1)-selective inhibitor, which showed a quick and significant effect on patients with atopic dermatitis in several phase 3 clinical studies. Although, an increasing number of studies have reported data on the real-world efficacy and safety of upadacitinib for the treatment of atopic dermatitis, no studies have yet been published in Korea. Objective: We assessed the real-world efficacy and safety of upadacitinib for the treatment of atopic dermatitis in Korean patients. Methods: A total of 17 patients with atopic dermatitis who received 15 mg of oral upadacitinib everyday for 16 weeks, were included in this retrospective single-center study. Based on electronic medical records, the clinical characteristics, Eczema Area and Severity Index (EASI) score, and adverse events were investigated. Results: The mean EASI score was significantly reduced at 4 weeks of upadacitinib treatment (8.81±9.00) and gradually reduced at week 8 (5.70±7.38), week 12 (4.55±6.23), and week 16 (4.58±6.74) (p＜0.001). At week 16, 61.54%, 30.77%, and 15.38% of patients achieved EASI 75, EASI 90, and EASI 100 responses, respectively. There was no statistically significant difference between EASI 75 and EASI 90 by age or gender at week 16 (p＞0.05). A total of 13 people (76.5%) had adverse events, of which acne was the most common. In all patients, the symptoms were mild and self-limited, and no patient discontinued treatment. Conclusion Upadacitinib was effective and safe for Korean patients with atopic dermatitis in real-world clinical practice.

Background: Targeted therapy and immunotherapy such as programmed death-1 (PD-1) targeting have been introduced for treating many types of cancers, including primary cutaneous angiosarcoma (CA). However, studies that examined other targeted molecules in CA are scarce. Objective: We aim to declare the expression of endoglin and survivin in addition to PD-1 and assess the clinical correlation between the expression of these molecules and clinical variables, overall survival (OS), and progressionfree survival (PFS) in CA. Methods: We identified 51 patients diagnosed with CA at Asan Medical Center over the last 14 years, based on the staining results of paraffin sections of tissue samples for endoglin, survivin, and PD-1 that were reviewed by two dermatologists. Results: Statistical analysis for the correlation between results and clinical data of CA revealed that whereas 35 (63.6%) and 30 samples (54.5%) were positive for endoglin and survivin respectively, only nine samples were positive for PD-1 (16.4%). Co-expression of endoglin and survivin was detected in 24 lesions (p=0.013) and was significantly correlated to head, neck, face, and scalp (HNFS) lesions in CA (p=0.005, p=0.038, respectively). However, the expression of these target molecules did not correlate with the OS or PFS of CA. Conclusion Considering that HNFS type CA is associated with unfavorable clinical outcomes in similar populations, our findings can be helpful in matching patients with CA with effective targeted therapy.

Background: Nipple adenoma (NA) is a rare benign tumor arising in the lactiferous ducts of the nipple. It typically presents as a palpable nodule, erosion, or discharge with erythema of the nipple. NA is different from other mammary proliferative diseases of the nipple; however, its clinicopathologic characteristics have been scarcely elucidated. Objective: In this study, we aimed to assess the clinical and histopathological characteristics of NA and compare them with mammary Paget’s diseases and breast carcinomas of the nipple. Methods: We retrospectively reviewed fifteen patients with NA. Furthermore, we reviewed fifteen patients with nipple Paget’s diseases and five patients with breast carcinomas (ductal carcinoma in situ and invasive ductal carcinoma). Skin lesions’ clinical characteristics and general histopathological findings were investigated. Results: NA showed significantly early onset (p=0.014), delayed time for onset to diagnosis (p=0.026), and smaller lesion than other nipple malignant diseases (p＜0.001). NA was predominantly localized on the right side and exhibited as more palpable mass and less nipple discharge as initial symptoms. Estimated prevalence of Korean cases (0.026%) was twice higher than Western countries (0.012%). p16 immunostaining in NA and other malignant diseases did not differ. Conclusion NA is a benign neoplasm arising on the nipple. NA showed earlier onset with smaller size at initial presentation than other malignant diseases which presented more crusts. Unnecessary surgical procedures for NA should be avoided with preceding clinical differential diagnosis.

Background: Riehl’s melanosis of the face and neck has been reported in middle-aged women who have darker skin types. Recently, cases of Riehl’s melanosis have been on the rise in Korea, which might reflect the increased use of various cosmetic products and procedures. Objective: This study was designed to analyze the clinicopathological characteristics and treatment outcomes of Riehl’s melanosis in Korean patients. Methods: We closely observed 80 patients with Riehl’s melanosis diagnosed in Asan Medical Center and Hanyang University Medical Center between 2005 and 2015. A skin biopsy was analyzed in 51 patients, and a patch test was carried out in 16 patients. Results: Patients with chronic Riehl’s melanosis (＞12 months) had an increased frequency of previous laser treatments. Patients with acute Riehl’s melanosis (＜3 months) reported a previous history of dry skin, itching, or irritation as a result of the use of hair dye. Patients older than 50 years, with darker skin type, and with a longer disease duration (＞12 months) had poor response rates. Chronic Riehl’s melanosis may be preceded by repeated irritation of barrier-compromised skin, and acute Riehl’s melanosis seems to be an allergic form of Riehl’s melanosis. Conclusion Riehl’s melanosis has different clinical manifestations according to disease duration and different treatment responses based on disease duration.

Pheochromocytoma and paraganglioma (PPGLs) are rare catecholamine-secreting neuroendocrine tumors but can be life-threatening. Although most PPGLs are benign, approximately 10% have metastatic potential. Approximately 40% cases are reported as harboring germline mutations. Therefore, timely and accurate diagnosis of PPGLs is crucial. For more than 130 years, clinical, molecular, biochemical, radiological, and pathological investigations have been rapidly advanced in the field of PPGLs. However, performing diagnostic studies to localize lesions and detect metastatic potential can be still challenging and complicated. Furthermore, great progress on genetics has shifted the paradigm of genetic testing of PPGLs. The Korean PPGL task force team consisting of the Korean Endocrine Society, the Korean Surgical Society, the Korean Society of Nuclear Medicine, the Korean Society of Pathologists, and the Korean Society of Laboratory Medicine has developed this position statement focusing on the comprehensive and updated diagnosis for PPGLs.

Purpose: The study aimed to identify the effects of sleep hygiene (use of caffeine, alcohol, night eating syndrome, stress, and coping styles), social network, and smartphone-related factors on quality of sleep in young adults. Methods: This was a descriptive research design. Participants completed a questionnaire on evidence-based variables including caffeine intake, alcohol consumption, social network, night eating syndrome, stress, coping styles, and smartphone-related factors. Stepwise multiple regression was used for data analysis to identify factors that influenced the participants’ quality of sleep. This study included 288 young adults in South Korea. Results: This study identified the factors affecting quality of sleep in young adults. Their average weekly sleep duration was 6.86 hours with low sleep quality, indicated by a score of 59.34 points (range 17-100). The predictors of sleep quality were sleep mood, sub-items of night eating syndrome, effects of pain over the last four weeks, and social networks, which explained 33% of the variance. Conclusion Sleep-induced diseases in young adults could be prevented by identifying sleep mood, pain, and social networks, which is important for health and using them as a basis for intervention.

Pheochromocytoma and paraganglioma (PPGLs) are rare catecholamine-secreting neuroendocrine tumors but can be life-threatening. Although most PPGLs are benign, approximately 10% have metastatic potential. Approximately 40% cases are reported as harboring germline mutations. Therefore, timely and accurate diagnosis of PPGLs is crucial. For more than 130 years, clinical, molecular, biochemical, radiological, and pathological investigations have been rapidly advanced in the field of PPGLs. However, performing diagnostic studies to localize lesions and detect metastatic potential can be still challenging and complicated. Furthermore, great progress on genetics has shifted the paradigm of genetic testing of PPGLs. The Korean PPGL task force team consisting of the Korean Endocrine Society, the Korean Surgical Society, the Korean Society of Nuclear Medicine, the Korean Society of Pathologists, and the Korean Society of Laboratory Medicine has developed this position statement focusing on the comprehensive and updated diagnosis for PPGLs.

Background: Psoriasis is a common chronic inflammatory skin disease. The development of psoriasis is dependent on many intercellular events such as innate immunity and T cell-mediated inflammation. Furthermore, genetic factors are strongly implicated in the pathophysiology of psoriasis. Although a variety of susceptible genes are identified, it is likely that many important genes remain undisclosed. Objective: The aim of this study is to investigate the possible role of lysine demethylase 2A (KDM2A) in the pathophysiology of psoriasis. Methods: We examined the expression of KDM2A using a well established imiquimod-induced psoriasiform dermatitis model. Results: Immunohistochemistry analysis showed that expression of KDM2A was increased in imiquimod-induced psoriasiform dermatitis. Consistent with this result, KDM2A level was markedly increased in the epidermis of psoriatic patient. When keratinocytes were stimulated with TLR3 agonist poly(I:C), KDM2A was increased at both the mRNA and protein levels. Poly(I:C) increased the expression of psoriasis-related cytokines including tumor necrosis factor-α, interleukin-8, and CCL20, and KDM2A inhibitor daminozide enhanced the poly(I:C)-induced cytokine expression. Finally, topical co-application of imiquimod and daminozide exacerbated the imiquimod-induced psoriasiform dermatitis. Conclusion Together, these results suggest that KDM2A is increased to negatively regulate the inflammatory reaction of epidermal keratinocytes in psoriasis.