Rhododendrol-induced leukoderma update II: Pathophysiology, mechanisms, risk evaluation, and possible mechanism-based treatments in comparison with vitiligo.

A small proportion of individuals utilizing cosmetics containing rhododendrol developed leukoderma with various pathological conditions, in some cases indistinguishable from vitiligo. In this review, we investigate and evaluate the major considerations for developing rhododendrol-induced leukoderma based on data from original or review articles published in the literature to provide a wide range of information regarding the pathophysiology, mechanisms, risk evaluation, and possible mechanism-based treatments. We compile and discuss the latest information, including data related to the cytotoxicity of rhododendrol, cytoprotective functions, and involvement of the immune system, and consider the possibility of novel treatments based on the differences between individual patients and on the mechanism underlying the onset of the condition. Understanding the pathophysiology of rhododendrol-induced leukoderma helps not only elucidate the mechanisms of non-segmental vitiligo onset and progression, but also suggests prevention and treatment.

Rhododendrol-induced leukoderma update I: Clinical findings and treatment.

Individuals who used skin-whitening cosmetics (quasi-drugs) containing 2% rhododendrol-containing agents, developed leukoderma at a higher frequency than those who have used other skin-whitening cosmetics. The Rhododenol Research Team (RD-Team) was formed and commissioned by Kanebo Cosmetics Inc. to conduct research in treatments of rhododendrol-induced leukoderma (RDL), to evaluate effective treatment options from a medical standpoint, and provide information to a wide range of people. In this study, we evaluated the efficacy of various treatments for RDL from a medical perspective, based on the information published in the literature as original or review articles. We searched the PubMed (international) and the Igaku Chuo Zasshi (ICHUSHI) (Japanese) databases using the keywords "Rhododenol" and "rhododendrol", for articles published between July 2013 and November 2020. We discuss the main clinical findings and treatments (topical, oral, phototherapy, and surgical) of this condition based on the literature review. We found that ultraviolet light therapy is the most effective treatment for RDL. We have also summarized reports of the efficacy of oral vitamin D3 in RDL. A topical prostaglandin derivative has been reported in a new study to be effective. We have provided guidance for patients using self-tanning and skin-whitening agents to improve their quality of life. Finally, we have highlighted the importance of providing patients with information on contact dermatitis and instructing them to discontinue product use immediately if they develop any symptoms of contact dermatitis while using skin-whitening agents.

Regular sweating activities for the treatment of cholinergic urticaria with or without acquired idiopathic generalized anhidrosis.

Cholinergic urticaria (CholU) decreases affected individuals' quality of life because they must avoid stimuli including exercise and hot bathing. Although case reports have indicated that regular sweating activities are effective for CholU with hypohidrosis, little evidence is available. This retrospective medical record review examined CholU patients who received any form of treatment at our hospital. Twenty-seven cases (78% men; median age 22 years, range 12-70 years) were analyzed. Fourteen (52%) patients had acquired idiopathic generalized anhidrosis (AIGA). Among the 12 patients receiving sweating therapy (4 with, 8 without AIGA), improvement of symptoms was confirmed in 11 (92%; sweating therapy alone: n = 5, with H1 blocker: n = 5, with steroid pulse: n = 1) including 8 (67%) showing complete response (CR). In this sweating-therapy group, CR was achieved by six of the eight (75%) patients without AIGA and two of the four (50%) patients with AIGA. Among the 15 patients without sweating therapy, symptom improvement was observed in 9 (60%; steroid pulse: n = 7, H1 blocker: n = 2) including 1 (7%) achieving CR. Sweating therapy was safely undertaken except in one case in which the patient showed angioedema and anaphylaxis. Regular sweating activities could be a potential therapeutic option for CholU patients.

Prognostic Factors and Long-Term Efficacy of Tonsillectomy in 17 Patients with Pustulotic Arthro-Osteitis.

In this case study, we aimed to evaluate the disease condition of patients with pustulotic arthro-osteitis (PAO) at 36-month post-tonsillectomy. A retrospective analysis of the cases of 17 patients with PAO who were resistant to initial systemic treatments and underwent tonsillectomy at our hospital in 2006-2016 was conducted. The patients' disease condition at 1-, 24-, and 36-month post-tonsillectomy was assessed by the visual analog scale (VAS) score for osteoarthropathic pain, the disease duration, the area of palmoplantar lesions, and the Palmoplantar Pustular Psoriasis Area Severity Index (ppPASI). In the minimum follow-up of 36-month post-tonsillectomy in 17 patients, the median ppPASI and VAS scores decreased from 12 to 1 and from 80 to 20, respectively. Thirteen patients with ≥70% improvement in their VAS scores maintained the same good condition after ≥36 months, whereas four patients with <70% improvement in their VAS scores did not show remarkable improvement after that time point. Furthermore, we found that the improvement in VAS score was not associated with the disease duration or the patients' pre-tonsillectomy ppPASI values. Tonsillectomy might be an alternative treatment option for patients with PAO. Long-term efficacy against pain can be predicted by evaluating a patient's improvement at 1-month post-tonsillectomy.

Association between PD-L1 expression and lymph node metastasis in cutaneous squamous cell carcinoma.

AIM: To clarify the relationship between programmed cell death ligand 1 (PD-L1) expression in cutaneous squamous cell carcinoma (cSCC) and clinicopathological variables. METHODS: We examined PD-L1 expression in tumor cells (TCs) and tumor infiltrating immune cells (ICs) in 46 cases of cSCC by immunohistochemistry. In each case, we employed two methods-intensity and proportion scores-to evaluate PD-L1 expression in TCs. For the evaluation of PD-L1 expression in ICs, only the proportion score was used. Association between PD-L1 expression and clinicopathological variables was analyzed using Fisher's exact test. RESULTS: High intensity scores in TCs were observed in 18 of the 46 cases (39.1%) and low intensity scores were observed in 28 cases (60.9%). Applying the proportions, using cut-off values of ≥1% and 50%, positive scores in TCs were observed in 36 (78.3%) and 20 cases (43.5%), respectively. PD-L1-positive ICs were observed in 29 (63%) and seven cases (15.2%), using cut-off values of ≥1% and 10%, respectively. The high intensity scores in TCs correlated with lymph node metastasis (P = 0.008) and female gender (P = 0.017), although positive proportions in TCs or ICs were not significantly related to lymph node metastasis. A multivariate analysis showed that high intensity of PD-L1 expression in TCs was an independent risk factor for lymph node metastasis. CONCLUSIONS: The results suggested that high intensity of PD-L1 expression in TCs is associated with lymph node metastasis in cSCC.

Dermoscopic features distinctive for extraocular sebaceous carcinoma.

We examined dermoscopic features of three cases of extraocular sebaceous carcinoma and reviewed the literatures. The yellowish structures, polymorphous vessels and ulceration were common findings in our cases and all cases of the previous reports. The appearance of whitish-pink areas has not been described previously. Our results suggested that the combination of four dermoscopic features, whitish-pink areas, yellowish structures, polymorphous vessels and ulceration might be distinctive in extraocular sebaceous carcinoma.

Keratinocytes in atopic dermatitis express abundant ΔNp73 regulating thymic stromal lymphopoietin production via NF-κB.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease that often cannot be completely controlled by modern medicine. Since multiple factors are intricately involved in the pathogenesis of AD, wide-ranging research is required for further advancement of AD treatment. Epidermal keratinocytes are the forefront to the external environment and play a pivotal role in the initiation of immune reaction against exogenous invasion. OBJECTIVE: Thymic stromal lymphopoietin (TSLP) is a keratinocyte-derived cytokine that induces differentiation and activation of type 2 helper T cells and innate lymphoid cells, cardinal effectors in pathophysiology of AD. We previously reported that ΔNp63, a p53-related molecule, regulates the expression of TSLP receptors and suggested the entity of a potential TSLP autocrine loop in the AD epidermis. In this study, we further explored the significance of p53 family transcription factors in TSLP production from human keratinocytes. METHOD: Expression profile of p73, a p53-related molecule, was evaluated in human AD tissue by immunohistochemistry. In addition, the function of p73 in producing TSLP was investigated with in vitro cultured keratinocytes via molecular biological analysis. RESULTS: ΔNp73 was abundantly expressed in the AD epidermis and increased the release of TSLP via NF-κB activation. Furthermore, the Toll-like receptor 3 signal enhanced ΔNp73 expression and thereby induced TSLP expression. CONCLUSION: Our results indicate that ΔNp73 is an additional participant in the mechanism of TSLP production. Amending the aberrant state of keratinocytes, represented by overexpression of ΔNp73, can be a novel therapeutic target of AD.

Serum cytokeratin 19 fragment 21-1 is a useful tumor marker for the assessment of extramammary Paget's disease.

Cytokeratin 19 fragment 21-1 (CYFRA 21-1) has been used as a tumor marker for several malignancies. However, to date, no studies have assessed whether CYFRA 21-1 could be a useful marker for extramammary Paget's disease (EMPD). The present study aimed to evaluate the significance of CYFRA 21-1 as a serum tumor marker for EMPD progression. Concentrations of serum CYFRA 21-1 and carcinoembryonic antigen (CEA) in 13 cases of EMPD were measured prior to undergoing treatment at Sapporo Medical University Hospital from January 2014 to May 2016. Four of the 13 patients had lymph node metastases at diagnosis, but none had distant metastases. Immunohistochemistry indicated that all 13 primary tumors and four metastatic tumors in lymph nodes were positive for cytokeratin 19. Although none of the 13 patients showed high serum CEA levels, six patients (46.2%) had elevated serum CYFRA 21-1. Furthermore, CYFRA 21-1 was reduced in association with post-treatment tumor reduction in all six patients. Among these six patients, four developed recurrence and metastasis during the follow-up period. CYFRA 21-1 was re-elevated in all four of these patients; however, serum CEA was elevated only in the patient with distant metastasis. These results suggest that CYFRA 21-1 is more sensitive compared with CEA, and can be useful as a tumor marker for evaluating tumor progression and treatment efficacy in patients with EMPD.

Clinical and epidemiological analysis in 149 cases of rhododendrol-induced leukoderma.

Rhododendrol-induced leukoderma is an acquired depigmentation that develops mainly at the contact site after repeated use of skin-whitening cosmetics containing rhododendrol. In most cases, cessation of further depigmentation or occurrence of repigmentation is observed after discontinuing the use of cosmetics. However, some patients develop vitiligo vulgaris through the spread of depigmentation into the non-exposed areas. Our study aims to investigate the patient-specific factors that may affect the extent of depigmentation or repigmentation, as well as development of vitiligo vulgaris. The degree of depigmentation of the face, neck and hands where exposed to rhododendrol was scored using photographs over time. The relationships between depigmentation score at first visit/improvement rate of depigmentation score and patient demographics were evaluated and three important clinical observations were made. First, repigmentation of the face was superior compared with that of the hands and neck, suggesting a possible role for the migration and differentiation of melanocyte stem cells from hair follicles, as a mechanism of repigmentation. Second, the intensity of rhododendrol exposure did not contribute to differences in the severity of depigmentation. This suggested a possibility of underlying genetic susceptibility to melanocyte cytotoxicity or immune reaction. Third, depigmentation score at first visit and past history of atopic dermatitis were significantly high in patients who developed vitiligo vulgaris. This suggested that severe chemical damage of melanocytes by rhododendrol leads to a higher risk of developing vitiligo vulgaris through the possible involvement of an immune reaction. These clinical observations may help to further understand the pathogenesis of rhododendrol-induced leukoderma.