Background/Aims: Chronic hepatitis B (CHB) is related to an increased risk of extrahepatic malignancy (EHM), and antiviral treatment is associated with an incidence of EHM comparable to controls. We compared the risks of EHM and intrahepatic malignancy (IHM) between entecavir (ETV) and tenofovir disoproxil fumarate (TDF) treatment. Methods: Using data from the National Health Insurance Service of Korea, this nationwide cohort study included treatment-naïve CHB patients who initiated ETV (n=24,287) or TDF (n=29,199) therapy between 2012 and 2014. The primary outcome was the development of any primary EHM. Secondary outcomes included overall IHM development. E-value was calculated to assess the robustness of results to unmeasured confounders. Results: The median follow-up duration was 5.9 years, and all baseline characteristics were well balanced after propensity score matching. EHM incidence rate differed significantly between within versus beyond 3 years in both groups (P<0.01, Davies test). During the first 3 years, EHM risk was comparable in the propensity score-matched cohort (5.88 versus 5.84/1,000 person-years; subdistribution hazard ratio [SHR]=1.01, 95% confidence interval [CI]=0.88–1.17, P=0.84). After year 3, however, TDF was associated with a significantly lower EHM incidence compared to ETV (4.92 versus 6.91/1,000 person-years; SHR=0.70, 95% CI=0.60–0.81, P<0.01; E-value for SHR=2.21). Regarding IHM, the superiority of TDF over ETV was maintained both within (17.58 versus 20.19/1,000 person-years; SHR=0.88, 95% CI=0.81–0.95, P<0.01) and after year 3 (11.45 versus 16.20/1,000 person-years; SHR=0.68, 95% CI=0.62–0.75, P<0.01; E-value for SHR=2.30). Conclusions TDF was associated with approximately 30% lower risks of both EHM and IHM than ETV in CHB patients after 3 years of antiviral therapy.

Background: Melatonin receptors are present in the human skin and retina. These receptors can be stimulated by light emitting diodes (LEDs) at specific wavelengths, thereby inducing cutaneous photorejuvenation. However, the underlying mechanism remains unclear. Objective: To evaluate the influence of LEDs at specific wavelengths on melatonin membrane receptor (MT1) and cutaneous photorejuvenation via the MT1 pathway in vitro. Methods: Normal human dermal fibroblasts (HDFs) were irradiated using LEDs at different wavelengths (410~940 nm) at a dose of 1 J/cm 2 . MT1 activity was evaluated after melatonin stimulation and LED irradiation. Thereafter, the expressions of collagen (COL) and matrix metalloproteinases (MMPs), with and without luzindole (MT1/2 receptor antagonist), were investigated via semi-quantitative reverse transcription polymerase chain reaction (PCR), real-time PCR, western blotting, and enzyme-linked immunosorbent assay. Results: In HDFs, the MT1 mRNA and protein levels increased significantly in response to melatonin (dose, 50 nM) (p<0.01) and LED irradiation at 595, 630, 850, and 940 nm (p<0.01). LED irradiation up-regulated COL type I and down-regulated MMP-1. Compared to LED irradiation without luzindole, LED irradiation with luzindole produced no significant increase in COL type I mRNA and protein levels (p<0.01). Conclusion We found that LED irradiation induces collagen synthesis and MMP-1 inhibition in HDFs via MT1 activation. Additionally, multiple LED wavelengths (595, 630, 850, and 940 nm) stimulated MT1 in HDFs, unlike in the eyes, where only blue light induced plasma melatonin suppression. This suggests the possibility of the melatoninergic pathway in photorejuvenation.

Background: Rosacea is a chronic inflammatory skin disease with a pathophysiological mechanism that remains unclear. Recently, dysregulation of the sensory nerve system has been implicated in the development of this condition. Objective: This study aimed to investigate the effect of capsaicin on neuroinflammatory mediators in rosacea. In addition, this study aimed to evaluate the attenuating effects of capsazepine, a transient receptor potential vanilloid type 1 (TRPV1) antagonist. Methods: We obtained skin tissue from both rosacea patients and normal individuals for an in vivo study. In addition, normal human epidermal keratinocytes (NHEKs) were cultured, and treated with capsaicin and capsazepine for an in vitro study. Quantitative changes in neuroinflammatory mediators were evaluated by semi-quantitative reverse transcription-polymerase chain reaction (PCR), real-time PCR, enzyme-linked immunosorbent assay, and immunofluorescence staining. Results: The data showed the increase of TRPV1, TRPV4, cathelicidin (LL37) and tumor necrosis factor-α (TNF-α) in skin tissue by real-time PCR. In addition, the data showed that cathelicidin (LL37), kallikrein-5 (KLK-5), TNF-α, vascular endothelial growth factor (VEGF), interleukin (IL)-1α, IL-1β, IL-8, and protease-activated receptor 2 (PAR2) increased in capsaicin-treated NHEKs. Capsazepine attenuated the expression of TRPV1 and other mediators, except for IL-8, in capsaicin-treated NHEKs. Conclusion We confirmed that TRPV1, TRPV4, cathelicidin (LL37) and TNF-α are increased in rosacea skin, and that capsaicin is associated with increase of neuroinflammatory mediators such as LL37, KLK-5, TNF-α, VEGF, IL-1α, IL-1β, IL-8, and PAR2. Modulators or inhibitors of neuroinflammatory mediators including TRPV1 could be potential therapeutic option in the treatment of patients with rosacea.

At the end of 2019, the cause of pneumonia outbreaks in Wuhan, China, was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In February 2020, the World Health Organization named the disease cause by SARS-CoV-2 as coronavirus disease 2019 (COVID-19). In response to the pandemic, the Korean Cancer Association formed the COVID-19 task force to develop practice guidelines. This special article introduces the clinical practice guidelines for cancer patients which will help oncologists best manage cancer patients during the COVID-19 pandemic.

Background: Breast reconstruction using an extended latissimus dorsi (eLD) flap can supplement more volume than reconstruction using various local flaps after partial mastectomy, and it is a valuable surgical method since the reconstruction area is not limited. However, when performing reconstruction, the surgeon should consider latissimus dorsi (LD) volume reduction due to postoperative chemotherapy (POCTx) and postoperative radiotherapy (PORTx). To evaluate the effect of POCTx and PORTx on LD volume reduction, the effects of each therapy—both separately and jointly—need to be demonstrated. The present study quantified LD volume reduction in patients who underwent POCTx and PORTx after receiving breast-conserving surgery (BCS) with an eLD flap. Methods: This study included 48 patients who received immediate breast reconstruction using an eLD flap from January 2013 to March 2017, had chest computed tomography (CT) 7–10 days after surgery and 10–14 months after radiotherapy completion, and were observed for more than 3 years postoperatively. One surgeon performed the breast reconstruction procedures, and measurements of breast volume were obtained from axial CT views, using a picture archiving and communication system. A P-value <0.05 was the threshold for statistical significance. Results: The average volume reduction of LD at 10–14 months after completing POCTx and PORTx was 64.5% (range, 42.8%–81.4%) in comparison to the volume measured 7–10 days after surgery. This change was statistically significant (P<0.05). Conclusions Based on the findings of this study, when harvesting an eLD flap, surgeons should anticipate an average LD volume reduction of 64.5% if chemotherapy and radiotherapy are scheduled after BCS with an eLD flap.

At the end of 2019, the cause of pneumonia outbreaks in Wuhan, China, was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In February 2020, the World Health Organization named the disease cause by SARS-CoV-2 as coronavirus disease 2019 (COVID-19). In response to the pandemic, the Korean Cancer Association formed the COVID-19 task force to develop practice guidelines. This special article introduces the clinical practice guidelines for cancer patients which will help oncologists best manage cancer patients during the COVID-19 pandemic.

Background: Pigmented contact dermatitis (PCD) is a non-eczematous contact dermatitis characterized by hyperpigmentation with few or no signs of dermatitis. The pathomechanism of PCD is still unknown; there are few case reports of PCD caused by hair dye, henna, and cosmetics. Objective: This study aimed to analyze the clinical features and the significance of risk factors in adult Korean patients with PCD. Methods: We retrospectively reviewed 75 patients with PCD. Clinical features including age, sex, duration, location, and risk factors were obtained from electronic medical records. To determine the significance of the risk factors of PCD, we compared these patients with 155 patients diagnosed with allergic contact dermatitis (ACD) without hyperpigmentation. Results: The mean age of onset of PCD in patients was 55.5 years, and the male:female ratio was 1:14. The mean duration of PCD was 16.3 months. The number of patients with PCD who had histories of hair dye use (n=67, 89.3%) and health supplement consumption (n=18, 24.0%) was significantly higher than that of patients with ACD. There were no significant differences in medication, cosmetic changes, stress history, results of patch test, patch testing with the patient’s own products, immunoglobulin E (kU/L), and eosinophils (cells/μL). Conclusion This study analyzed the clinical features and risk factors of PCD and ACD in adult Korean patients, and it suggests that PCD may be caused by irritation induced by variable factors and not allergic reactions.

Background: Pigmented contact dermatitis (PCD) is a non-eczematous contact dermatitis characterized by hyperpigmentation with few or no signs of dermatitis. The pathomechanism of PCD is still unknown; there are few case reports of PCD caused by hair dye, henna, and cosmetics. Objective: This study aimed to analyze the clinical features and the significance of risk factors in adult Korean patients with PCD. Methods: We retrospectively reviewed 75 patients with PCD. Clinical features including age, sex, duration, location, and risk factors were obtained from electronic medical records. To determine the significance of the risk factors of PCD, we compared these patients with 155 patients diagnosed with allergic contact dermatitis (ACD) without hyperpigmentation. Results: The mean age of onset of PCD in patients was 55.5 years, and the male:female ratio was 1:14. The mean duration of PCD was 16.3 months. The number of patients with PCD who had histories of hair dye use (n=67, 89.3%) and health supplement consumption (n=18, 24.0%) was significantly higher than that of patients with ACD. There were no significant differences in medication, cosmetic changes, stress history, results of patch test, patch testing with the patient’s own products, immunoglobulin E (kU/L), and eosinophils (cells/μL). Conclusion This study analyzed the clinical features and risk factors of PCD and ACD in adult Korean patients, and it suggests that PCD may be caused by irritation induced by variable factors and not allergic reactions.