Search

Asymmetric small interfering RNAs (asiRNAs) that mediate RNA interference have been investigated for therapeutic use in various tissues, including skin tissue. Androgenetic alopecia (AGA) is caused by a combination of genetic factors, resulting in sensitivity to dihydrotestosterone (DHT), which binds to the androgen receptor (AR) to mediate a series of biomolecular changes leading to hair loss. This study aimed to evaluate the therapeutic potential of a cell-penetrating, AR-targeting asiRNA (cp-asiAR) for AGA treatment, which was designed to silence the

Background: Nail apparatus melanoma (NAM) is a subtype of cutaneous melanoma occurring at nail units and belongs to the acral lentiginous melanoma subgroup. Due to its unique anatomical structure to protect the acral site, mechanical trauma may have a clinicoprognostic impact on NAM. Therefore, we investigated the clinicoprognostic and histopathological characteristics of NAM according to the presence of trauma history prior to melanoma development. Methods: Clinicopathological and follow-up data of patients with NAM according to trauma history were obtained. Results: We included 87 patients with NAM, 21.8% of whom had a previous trauma history. Trauma-related NAMs were more likely to involve the toenail (p = 0.040), include a high proportion of amelanotic melanomas (p = 0.038) as well as nail bed tumor (p = 0.013), and have a longer time interval between the onset of nail change and confirmed diagnosis (p = 0.012). Moreover, survival analysis revealed that trauma-related NAMs more frequently showed progression in general (p = 0.034) and nodal metastasis (p = 0.047) and had worse prognosis in terms of progression-free survival (p = 0.004). Conclusion: In conclusion, NAMs with previous trauma have unique clinicoprognostic characteristics. The specific clinicopathological features of NAMs according to trauma indicate that trauma may play a role in melanoma development.

The clinicoprognostic implications of head and neck involvement of mycosis fungoides (MF) are poorly understood.To evaluate the association of head and neck involvement on the clinicoprognostic features of MF.The clinical features and survival outcomes of patients with MF in a Korean academic medical center database were retrospectively evaluated according to the presence of head and neck involvement at diagnosis.Cases of MF with (group A, n = 39) and without (group B, n = 85) head and neck involvement at diagnosis were identified. Advanced-stage disease (stages IIB-IVB) was more common in group A (43.6%) than in group B (5.9%) (P .001). MF progression, extracutaneous dissemination, and large-cell transformation more commonly occurred in group A than in group B. The 10-year overall survival rate was worse in group A (53.4%) compared with group B (81.6%) (P .001). Head and neck involvement at diagnosis was associated with poor prognosis in early-stage MF (stages IA-IIA) and was independently associated with worse progression-free survival (hazard ratio, 24.4; 95% confidence interval, 2.2-267.6; P = .009).A single center, retrospective design.Head and neck involvement of MF was associated with a poor prognosis.

The association between psoriasis and alopecia areata has not been thoroughly investigated. The objective of this study is to investigate the association of psoriasis with alopecia areata. An electronic search was conducted in August 2021. The analysis included studies that reported sufficient data on the prevalence, odds, or hazard of alopecia areata in patients with psoriasis or that of psoriasis in patients with alopecia areata. Meta-analysis using an inverse variance method was performed with a random-effects model, assuming inherent heterogeneity between the included studies. The subgroup analyses were performed according to the age group and study quality. A total of 27 studies were included. The pooled prevalence of alopecia areata among patients with psoriasis was 0.5% (95% confidence interval [CI], 0.3-0.7%). The pooled odds ratio of alopecia areata among patients with psoriasis was 2.71 (95% CI, 2.29-3.21), whereas the pooled prevalence of psoriasis among patients with alopecia areata was 2.5% (95% CI, 2.0-3.0%). Moreover, the pooled odds ratio of psoriasis among patients with alopecia areata was 3.52 (95% CI, 1.27-9.74). The association of psoriasis and alopecia areata remained in the subgroup analyses according to the age group and study quality. In conclusion, this study suggests a bidirectional association between psoriasis and alopecia areata. Clinical examinations may be necessary to determine the presence of comorbid alopecia areata in patients with psoriasis and vice versa.

Use of stem cells to treat various diseases in dermatology has been of interest. Conditioned media with the growth factors secreted from stem cells has been used as a topical agent. We report a case of foreign body granulomas that appeared days after dermal injection of the conditioned media mimicking scars at all injection sites.

Cold atmospheric plasma (CAP) has been incorporated into various fields, including promotion of cutaneous wound healing. Atopic dermatitis (AD) is a chronic cutaneous condition characterized by inflammation-induced skin wounds and impaired skin barrier function. To investigate whether CAP may improve AD using an animal model. Dermatophagoides farinae extracts (DFE)-induced murine models of AD were used in this study. The plasma-treated group received a total of 6 CAP treatments during 2 weeks, while the control group did not receive any treatment. Differences in dermatitis severity, transepidermal water loss (TEWL), serum level of immunoglobulin (Ig) E and epidermal thickness were evaluated in both groups. The dermatitis severity was significantly improved by CAP treatment. TEWL was lower in the plasma-treated group compared with the non-treated control group. Serum Ig E dropped significantly after treatment with CAP. Difference in epidermal thickness of the ear skin was not significant between the plasma-treated and non-treated groups. Localized treatment of AD with CAP decreases dermatitis severity, TEWL, and serum Ig E level. These results show CAP’s potentials as a novel therapeutic modality for AD.

Dermatofibrosarcoma protuberans (DFSP) is a rare fibrohistiocytic tumour of unknown pathogenesis with intermediate malignant potential. Although trauma has been hypothesized as a predisposing factor for DFSP development, clinicopathological characteristics of trauma-related DFSP have not been investigated.This study investigated the differences between trauma-associated DFSP and trauma-unrelated DFSP.Patients histopathologically diagnosed with DFSP from January 2000 to December 2019 at the Dermatology Department were included. Clinical, histopathological, prognostic features and trauma history were analysed.We recruited 141 patients with DFSP (mean age, 36.1 years; male: female, 1:1.01). Recurrence and systemic metastasis were observed in 15.6% and 2.8% of patients, respectively. Older patients were likely to develop DFSP at the trauma sites more frequently on the face and lower legs. The active-growing lesions were more frequently associated with trauma-related DFSP. Multivariable logistic regression revealed that age at diagnosis (OR: 1.031; 95% CI: 1.004-1.059; p = 0.024) and tumour growth (OR: 3.336; 95% CI: 1.162-9.578, p = 0.025) were significantly associated with trauma-related DFSPs.The age at diagnosis, lesion location and tumour growth were associated with DFSPs in this study. Analysis of DFSP with trauma history provides a deeper understanding of long-term trauma effects on sarcoma development.

The study aimed to compare the volume enhancement and the lifting capacity of two different hyaluronic acid gels for lip injection. Thirty-six Korean female patients were randomized into two groups according to the cross-linking degree of the hyaluronic acid filler injected. Using a fixed injection protocol, patients were injected with 1 mL of hyaluronic acid filler in the lips and followed up at four and 12 weeks after injection. Lip volume, lip projection, and columella–labial angle were measured using a 3-dimensional imaging system at each time point. Follow-up values were compared with baseline. Compared with pre-treatment values, there was a statistically significant increase in mean lip volume and lip projection at four and 12 weeks after injection, with no significant differences between the two groups. Lips injected with hyaluronic acid filler of intermediate cross-link density resulted in more acute angles than lips injected with lightly cross-linked hyaluronic acid. The difference was statistically significant at each follow-up time point. No serious complications were observed throughout the study period. Our results imply that in patients who want a prominent upper lip lift, lip injections using hyaluronic acid fillers with intermediate cross-linking density can be a good option due to their lift capacity. The degree of cross-linking may not be a significant determinant of simple lip volume augmentation when other variables are constant.

Comprehensive studies of primary cutaneous extranodal natural killer/T-cell lymphoma (PCENKTL) are scarce. The objectives of this study are to describe PCENKTL in terms of its clinical features, histopathology, immunophenotypes, and prognosis, and to analyze factors affecting patient survival outcomes. We searched four databases and include studies with extractable data. We also searched the Asan Medical Center database for cases of PCENKTL. We include a total of 289 patients. The mean age at diagnosis was 52.8 years and the female to male ratio was 1:1.2. The most common clinical morphology was a subcutaneous nodule, followed by ulceration. About half of the patients presented with disseminated skin lesions. The median overall survival was 12.0 months and the 5-year survival rate was 22.0%. There was no correlation between the clinical morphology or the histopathological features of the skin lesions with the patient outcomes. Advanced TNM stage, a disseminated skin lesion, tumor location on the leg or trunk, the presence of B symptoms, and a high International Prognostic Index score were associated with a worse prognosis, and chemoradiotherapy was associated with a better survival outcome as compared with chemotherapy alone in univariable analyses. In multivariable analyses, only advanced TNM stage and tumor location on the leg were associated with a worse prognosis. In conclusion, PCENKTL is an aggressive cutaneous lymphoma and its prognosis is associated with TNM stage and tumor location.

The diagnostic role of preferentially expressed antigen in melanoma (PRAME) immunohistochemistry has not been thoroughly evaluated for acral melanocytic tumors. The objective of this study was to evaluate the utility of this modality for the diagnosis of acral melanocytic tumors compared with other potential markers. Melanocytic tumors were classified as either acral nevi, challenging melanocytic tumors (superficial atypical melanocytic proliferation of uncertain significance (SAMPUS)-favor benign (SAMPUS-FB), SAMPUS-favor malignant (SAMPUS-FM)) or acral melanomas. A total of 106 acral melanocytic tumors including acral nevi (n = 32), SAMPUS-FB (n = 17), SAMPUS-FM (n = 20), and acral melanomas (n = 37) were included. Diagnostic power, assessed using an area under the receiver operating characteristic curve (AUC) for distinguishing acral melanomas and acral nevi, was highest for PRAME (AUC = 0.997), followed by c-Myc (AUC = 0.755), cyclin D1 (AUC = 0.652), and c-Kit (AUC = 0.573). At a PRAME expression level ≥30% as a positive test for acral melanoma, the sensitivity and specificity of this marker for discriminating acral melanoma from acral nevus were 100% and 96.9%, respectively. PRAME immunohistochemistry also discriminated SAMPUS-FM from SAMPUS-FB with a sensitivity and specificity of 90.0% and 76.5%, respectively. In conclusion, PRAME immunohistochemistry can be used effectively to distinguish between various spectra of acral melanocytic neoplasms.

The aim of this study was to evaluate the safety and efficacy of combined 1060-nm diode laser and 635-nm low-level laser therapy (LLLT) device for non-invasive reduction of the abdominal and submental fat. Forty-two healthy subjects received single laser treatment on both the abdomen and submental area. Ultrasound images measuring the thickness of abdominal and submental fat were taken at baseline, follow-up at 4, 8, and 12 weeks after treatment. Waist circumference and body weight were also measured at all visits. Adverse events were recorded at all visits. Subjects completed a satisfaction questionnaire at the end of the trial. Twelve weeks after a single treatment with the investigational device, ultrasound images showed statistically significant (P < 0.0001) reductions in abdominal and submental fat by 18.62 and 26.4%, respectively. In addition, significant (P < 0.0001) reduction in waist circumference was observed. Ninety-six percent of subjects rated that they were satisfied. Noted side effects were transient mild to moderate tenderness which subsided within 1 to 3 weeks. No serious treatment-related adverse events were reported. The dual wavelength device combining 1060-nm diode laser with 635-nm LLLT was safe and effective for non-invasive reduction of both abdominal and submental fat.

Primary cribriform carcinoma of the skin is an indolent, rare, adnexal tumor. Although its malignant potential remains uncertain, no recurrence or metastasis has been reported. A 33-year-old man presented with a solitary, erythematous, subcutaneous nodule on the right knee. The clinical impression was epidermal cyst, and the resected tumor demonstrated a well-circumscribed mass in the dermis and subcutis. The tumor was composed of two regions: a solid component and a cribriform component. The solid component (90%) showed multiple solid nests of epithelial cells. Individual cells had large, oval-to-round, hyperchromatic, pleomorphic nuclei with a nuclear groove. The cribriform component (10%) showed similar neoplastic cells with many prominent lumina. Some lumina had an eosinophilic substance that exhibited a positive periodic acid-Schiff reaction. No recurrence or metastasis was observed within a follow-up period of eight months after excision. In conclusion, we report the first case of primary cribriform carcinoma of the skin in Korea.

In this study, the clinicopathologic features and survival outcomes of patients with hyperpigmented MF from a single tertiary referral center database were retrospectively evaluated. Hyperpigmented MF accounted for 10.9% (14/128) of all MF cases. The mean age at diagnosis was 46.9 years, and the female-to-male ratio was 1:1.3. Concurrent hypopigmented, ichthyosiform, and poikilodermatous lesions were detected in 21.4%, 14.3%, and 14.3% of the patients, respectively. Histopathologically, most patients (85.7%) showed interface change with pigment incontinence. Double negative (CD4- and CD8-) immunophenotypes were more frequent in patients with hyperpigmented MF (25%) than in those with other MF subtypes (9.8%). Most patients (85.7%) had early-stage disease at diagnosis. The survival outcomes did not differ significantly between hyperpigmented and other MF subtypes. In conclusion, hyperpigmented MF often accompanies other atypical MF variants and is frequently associated with atypical immunophenotypes. The outcomes of hyperpigmented MF are comparable to those of other MF subtypes.

Background Kaposi sarcoma (KS) is a mesenchymal tumor with distinct histopathological features according to tumor progression. Programmed death-1 (PD-1) and its ligand PD-L1 play major roles in the immune escape strategy of tumors. Objectives This study evaluated expression of PD-1 and PD-L1 in various stages of KS and investigated associations between their expression and clinical characteristics. Methods Fifty cases with histopathologically diagnosed KS were classified as early or late stage. These specimens were stained with anti-PD-1 and anti-PD-L1 antibodies. The extent of expression in the intratumoral and peri-tumoral areas was judged by two dermatopathologists. Results PD-1 and PD-L1 were expressed in 72.2% (13/18) and 11.1% (2/18) of early-stage cases, respectively, compared with 43.8% (14/32) and 28.1% (9/32) of late-stage cases, respectively. At the late stage, PD-1 expression was significantly higher in the peri-tumoral area than in the intratumoral area (P = 0.001). PD-1 expression in the intratumoral area was significantly higher at the early stage than at the late stage (P = 0.013). PD-L1 expression in the peri-tumoral area was significantly higher at the late stage than at the early stage (P = 0.038). Conclusions The pattern of PD-1 and PD-L1 expression differs according to the stage of KS, but is unaffected by clinical variables.

Background Although cutaneous melanoma has been widely evaluated, data elucidating the clinical features and prognostic factors of cutaneous metastatic melanoma are limited. Objective To determine and compare the clinicoprognostic features of cutaneous metastasis in acral and nonacral melanoma. Methods The Asan Medical Center database was reviewed for cases of cutaneous metastatic melanoma that had been confirmed by skin biopsy between January 1996 and December 2017. Results Cutaneous metastasis occurred in 12.4% (61 of 492 cases) of our cohort. The frequency of cutaneous metastasis was higher in nonacral melanoma than that in acral melanoma. The mean duration between the initial diagnosis of a primary tumor and cutaneous dissemination was 19.8 months. Cutaneous metastasis developed earlier during the disease course in acral melanoma than that in nonacral melanoma. Cutaneous metastasis was more disseminated, involving multiple anatomy sites in nonacral melanoma than that in acral melanoma. In-transit metastasis was significantly more common in acral melanoma than that in nonacral melanoma. The disease stage at the time of cutaneous metastasis was not significantly different between acral and nonaral melanoma. In-transit metastasis was commonly associated with visceral involvement in acral melanoma but not in nonacral melanoma. The extent and multiplicity of cutaneous metastasis were dependent on the status of other viscera during the cutaneous metastasis. No significant difference in survival during the cutaneous metastasis was observed between acral and nonacral melanoma. Conclusion Clinicoprognostic features of cutaneous metastasis were different between acral and nonacral melanoma.

Background Primary cutaneous angiosarcoma (CA) is a rare but aggressive tumor with a high rate of local recurrence. This study was designed to analyze the clinicopathological features of primary CA and identify factors of cutaneous manifestations associated with the prognosis of angiosarcoma. Methods Medical records of 55 patients with primary CA were retrospectively analyzed to investigate clinical features, survivals, and prognostic factors. Anatomical location of tumor was classified to the scalp, face, and neck, and sites outside the head and neck. Results Primary CA presented cutaneous nodules (31/55, 47.2%), patches (13/55, 23.6%), and indurated plaques (11/55, 20.0%). Nodular lesion was significantly more common in CA on the scalp compared to CA on sites outside the scalp. Histologically, tumors presenting as nodular lesions on the scalp was predominantly composed of solid sheets of large pleomorphic cells, whereas non-nodular lesions composed of tumor cells between collagen bundles forming irregular vascular spaces. Cutaneous angiosarcoma on the scalp showed a worse prognosis compared to CA on sites outside the scalp. Patients presenting clinical morphology with nodules and multiple skin lesions showed significantly reduced overall survival (OS). Conclusion In primary CA, location on the scalp, morphology with nodules, and multiplicity of skin lesions significantly affected survival outcomes.

Excessive accumulation of submental fat (SMF) causes a lower face cosmetic problem. A lipolytic injectable has recently been developed as a solution. The objective of this study is to investigate the effects and safety of DWJ211 (a newly developed lipolytic injectable) in the reduction of SMF and to identify the optimum dose. In this multi-center, double-blind, placebo-controlled study, subjects with moderate to severe SMF were randomized to injections of DWJ211 0.5%, DWJ211 1%, DWJ211 2% or placebo in the submental area, every 4 weeks, up to Week 12. Efficacy was determined by improvements in physician-assisted SMF rating scales (PA-SMFRS) and subject-assisted SMF rating scales (SA-SMFRS) 4 weeks after the last treatment (Week 16). Safety was assessed by inquiries, subject diary entries of adverse events, laboratory tests, and vital sign checks. Of 140 enrolled subjects, 136 were included in the analysis. The proportions of subjects, who achieved ≥1-grade improvement on the PA-SMFRS were 41.7%, 65.7%, 84.4%, and 72.7%, and the proportions of subjects, who achieved ≥1-grade improvement on the SA-SMFRS were 50.0%, 71.4%, 93.8%, and 81.8% for the placebo, DWJ211 0.5%, DWJ211 1%, and DWJ211 2% group, respectively. Adverse drug reactions (ADRs) were more common in each of the treatment groups compared with placebo, with the most common ADR being injection site pain. No subjects experienced any serious adverse events. In conclusion, the 1% DWJ211 dose was beneficial for SMF reduction and had a tolerable safety profile. Thus, we selected 1% as the dose to be tested in a Phase 3 clinical trial.

Background Although deep neural networks have shown promising results in the diagnosis of skin cancer, a prospective evaluation in a real-world setting could confirm these results. This study aimed to evaluate whether an algorithm (http://b2019.modelderm.com) improves the accuracy of nondermatologists in diagnosing skin neoplasms. Methods A total of 285 cases (random series) with skin neoplasms suspected of malignancy by either physicians or patients were recruited in two tertiary care centers located in South Korea. An artificial intelligence (AI) group (144 cases, mean [SD] age, 57.0 [17.7] years; 62 [43.1%] men) was diagnosed via routine examination with photographic review and assistance by the algorithm, whereas the control group (141 cases, mean [SD] age, 61.0 [15.3] years; 52 [36.9%] men) was diagnosed only via routine examination with a photographic review. The accuracy of the nondermatologists before and after the interventions was compared. Results Among the AI group, the accuracy of the first impression (Top-1 accuracy; 58.3%) after the assistance of AI was higher than that before the assistance (46.5%, P = .008). The number of differential diagnoses of the participants increased from 1.9 ± 0.5 to 2.2 ± 0.6 after the assistance (P < .001). In the control group, the difference in the Top-1 accuracy between before and after reviewing photographs was not significant (before, 46.1%; after, 51.8%; P = .19), and the number of differential diagnoses did not significantly increase (before, 2.0 ± 0.4; after, 2.1 ± 0.5; P = .57). Conclusions In real-world settings, AI augmented the diagnostic accuracy of trainee doctors. The limitation of this study is that the algorithm was tested only for Asians recruited from a single region. Additional international randomized controlled trials involving various ethnicities are required.

Background Prabotulinumtoxin A has been shown to have efficacy for the treatment of upper-limb spasticity and improvement of moderate to severe glabellar lines. However, the efficacy and safety of prabotulinumtoxin A for crow's feet have not been evaluated. Objective This study compared the efficacy and safety of prabotulinumtoxin A and onabotulinumtoxin A in the treatment of crow's feet. Patients and methods A multicenter, randomized, double-blind, active-controlled, split-face study was conducted in subjects with bilateral symmetric, moderate to severe crow's feet at maximum smile. The investigators assessed the severity of crow's feet by using the facial wrinkle scale, and the subjects reported the improvement in severity, their subjective satisfaction, and perceived age. The primary efficacy outcome was the proportion of subjects with Grade 0 or 1 severity of crow's feet at maximum smile at Week 4 as assessed by the investigators. Results In the primary efficacy outcome assessment, there was no significant difference between the 2 groups (prabotulinumtoxin A, 65.02%; onabotulinumtoxin A, 62.56%; p = .0956). All secondary efficacy outcomes were also achieved. Adverse events related to injection were mild and recovered spontaneously. Conclusion Prabotulinumtoxin A and onabotulinumtoxin A have comparable efficacy and safety in the treatment of crow's feet.

The clinical and pathological features of lymphomatoid papulosis (LYP) are diverse. The objective of this study is to evaluate the clinical and pathological features associated with the prognosis and clinical course of LYP.The clinical and pathological features of LYP in a medical center database were retrospectively retrieved.Overall, 58 LYP patients were included in the study. The mean age at diagnosis was 39.1 years and the female-to-male ratio was 1:1.2. More than two-thirds (40/58, 69.0%) of the patients showed a chronic and recurrent disease course. A longer pre-diagnosis duration (odds ratio (OR), 1.01; 95% confidence interval (CI), 1.00-1.03) was significantly associated with secondary lymphoma development. Lower extremity involvement (OR, 10.40; 95% CI, 1.17-92.28) and the absence of eosinophils in the lesions (OR, 11.28; 95% CI, 1.01-126.24) were found to be significantly associated with the chronic and recurrent course of LYP.A longer pre-diagnosis duration is associated with secondary lymphoma, while a lower extremity involvement and the absence of lesional eosinophil infiltration are associated with the chronicity of LYP.

Background Distinguishing benign lesion from early malignancy in melanocytic lesions of the nail unit still remains a diagnostic challenge, both clinically and histopathologically. While several immunohistochemistry (IHC) stainings have been suggested to help discriminate benign subungual melanocytic proliferation (SMP) and subungual melanoma in situ (MIS), the diagnostic utility of IHC staining for cyclin D1 and PRAME has not been thoroughly investigated in melanocytic lesions of nail unit. Methods This retrospective study included cases of benign SMP and subungual MIS confirmed by biopsy at Asan Medical Center from January 2016 to December 2020. Cases of melanocytic activation without proliferation and melanoma where dermal invasion was identified were excluded. Cyclin D1 and PRAME expression was assessed by counting proportion of melanocytes with nuclear positivity under 200x magnification. Results A total of 14 patients with benign SMP and 13 patients with subungual MIS were included in this study. 11 patients with benign SMP (71.4%) and 5 patients with subungual MIS (38.5%) showed > 60% nuclear immunostaining for cyclin D1, respectively. While 13 patients with benign SMP (92.9%) showed totally negative staining for PRAME, 10 patients with subungual MIS (76.9%) exhibited > 50% nuclear immunostaining for PRAME. Using the cutoff of 10%, PRAME exhibited good overall discrimination between benign SMP and subungual MIS (AUC = 0.849, 95% CI = 0.659–0.957). Conclusions This study suggests that PRAME IHC staining as a reliable discriminator in distinguishing subungual MIS from benign SMP.

This was a single-center, unmasked, paralleled, randomized controlled trial.A randomized trial was conducted in a tertiary care institute in South Korea to validate whether artificial intelligence (AI) could augment the accuracy of nonexpert physicians in the real-world settings, which included diverse out-of-distribution conditions. Consecutive patients aged19 years, having one or more skin lesions suspicious for skin cancer detected by either the patient or physician, were randomly allocated to four nondermatology trainees and four dermatology residents. The attending dermatologists examined the randomly allocated patients with (AI-assisted group) or without (unaided group) the real-time assistance of AI algorithm (https://b2020.modelderm.com#world; convolutional neural networks; unmasked design) after simple randomization of the patients.Using 576 consecutive cases (Fitzpatrick skin phototypes III or IV) with suspicious lesions out of the initial 603 recruitments, the accuracy of the AI-assisted group (n = 295, 53.9%) was found to be significantly higher than those of the unaided group (n = 281, 43.8%; P = 0.019). Whereas the augmentation was more significant from 54.7% (n = 150) to 30.7% (n = 138; P0.0001) in the nondermatology trainees who had the least experience in dermatology, it was not significant in the dermatology residents. The algorithm could help trainees in the AI-assisted group include more differential diagnoses than the unaided group (2.09 vs. 1.95 diagnoses; P = 0.0005). However, a 12.2% drop in Top-1 accuracy of the trainees was observed in cases in which all Top-3 predictions given by the algorithm were incorrect.The multiclass AI algorithm augmented the diagnostic accuracy of nonexpert physicians in dermatology.

Several studies have determined the correlation between programmed cell death protein-1 (PD-1) and chronic plaque psoriasis (CPP). However, limited studies have assessed the association between PD-1 expression and the clinicoprognostic and distinct clinicopathological characteristics of CPP and guttate psoriasis (GP). Twenty-nine patients with skin biopsy-confirmed CPP were recruited at the Asan Medical Center between January 2018 and June 2020, and 33 patients with biopsy-confirmed GP were enrolled between January 2002 and June 2020. The clinicoprognostic and histopathological characteristics were analyzed according to immunohistochemical PD-1 expression in the epidermal or dermal inflammatory infiltrates. The CPP and GP lesions were divided into PD-1-low and PD-1-high groups. The CPP epidermal PD-1-high group had typical histopathological changes and significantly higher psoriasis area and severity index scores (p = 0.014) and disease duration (p = 0.009) than the epidermal PD-1-low group. In patients with GP, compared with the dermal PD-1-high group, the dermal PD-1-low group exhibited significantly higher disease duration (p = 0.002) and relapse rate of plaque psoriasis (p = 0.005) and significantly lower relapse-free survival (p = 0.016). Upregulated epidermal PD-1 expression was correlated with the chronicity and severity of CPP, while downregulated dermal PD-1 expression was correlated with poor prognosis of GP.

Although various skin cancer detection devices have been proposed, most of them are not used owing to their insufficient diagnostic accuracies. Laser-induced plasma spectroscopy (LIPS) can noninvasively extract biochemical information of skin lesions using an ultrashort pulsed laser.To investigate the diagnostic accuracy and safety of real-time noninvasive in vivo skin cancer diagnostics utilizing nondiscrete molecular LIPS combined with a deep neural network (DNN)-based diagnostic algorithm.In vivo LIPS spectra were acquired from 296 skin cancers (186 basal cell carcinomas, 96 squamous cell carcinomas, and 14 melanomas) and 316 benign lesions in a multisite clinical study. The diagnostic performance was validated using 10-fold cross-validations.The sensitivity and specificity for differentiating skin cancers from benign lesions using LIPS and the DNN-based algorithm were 94.6% (95% CI: 92.0%-97.2%) and 88.9% (95% CI: 85.5%-92.4%), respectively. No adverse events, including macroscopic or microscopic visible marks or pigmentation due to laser irradiation, were observed.The diagnostic performance was evaluated using a limited data set. More extensive clinical studies are needed to validate these results.This LIPS system with a DNN-based diagnostic algorithm is a promising tool to distinguish skin cancers from benign lesions with high diagnostic accuracy in real clinical settings.

With the increasing incidence of skin cancer, many noninvasive technologies to detect its presence have been developed. This review focuses on reflectance confocal microscopy (RCM), optical coherence tomography (OCT), high-frequency ultrasound (HFUS), electrical impedance spectroscopy (EIS), pigmented lesion assay (PLA), and Raman spectroscopy (RS) and discusses the basic principle, clinical applications, advantages, and disadvantages of each technology. RCM provides high cellular resolution and has high sensitivity and specificity for the diagnosis of skin cancer. OCT provides lower resolution than RCM, although its evaluable depth is deeper than that of RCM. RCM and OCT may be useful in reducing the number of unnecessary biopsies, evaluating the tumor margin, and monitoring treatment response. HFUS can be mainly used to delineate tumor depths or margins and monitor the treatment response. EIS provides high sensitivity but low specificity for the diagnosis of skin malignancies. PLA, which is based on the genetic information of lesions, is applicable for the detection of melanoma with high sensitivity and moderate-to-high specificity. RS showed high accuracy for the diagnosis of skin cancer, although more clinical studies are required. Advances in these technologies for the diagnosis of skin cancer can lead to the realization of optimized and individualized treatments.