Granuloma annulare is a relatively common inflammatory skin disease. The etiology is unknown; however, drugs have been considered as one of the predisposing conditions, and a few cases of granuloma annulare related to biologics have been recently reported. A 48-year-old man with a 25-year history of psoriasis visited our dermatological clinic. Ustekinumab was administered for the treatment of psoriasis. After 5 years of ustekinumab therapy, erythematous papules with an annular distribution appeared on his trunk and extremities. Skin biopsy supported the diagnosis of generalized granuloma annulare, and the patient continued to receive ustekinumab with oral methotrexate, cyclosporine, and steroids for 9 months. However, as the skin lesions aggravated, oral steroid treatment was continued, and secukinumab was administered instead of ustekinumab. The skin lesions improved and remained stable with the intermittent administration of oral steroids thereafter.

Background: Guselkumab, a human immunoglobulin-G1λ monoclonal antibody, selectively blocks the interleukin-23-mediated signaling pathway. It has emerged as a promising treatment option for moderate-to-severe psoriasis. However, no studies have reported real-world clinical data on guselkumab in patients with psoriasis in Korea. Objective: To investigate the effectiveness and safety of guselkumab in Korean patients with moderate to severe plaque psoriasis. Methods: We retrospectively reviewed patients with moderate-to-severe psoriasis who were treated with guselkumab at Pusan National University Hospital (Busan and Yangsan) from January 2019 to May 2021. Fifty-six patients with psoriasis who were treated with guselkumab were included in the study. Patient demographics, psoriasis area and severity index (PASI) scores, investigator’s global assessment scores, and adverse events were assessed. Results: The mean baseline PASI score (16.2±7.6) significantly decreased after 20 weeks of guselkumab treatment (p＜0.05). In total, 76.8%, 78.6%, and 88.1% of patients achieved a PASI90 response at 20, 28, and 52 weeks, respectively. Of 56 patients, 52 had a PASI90 response at the last follow-up visit. No serious adverse events were observed. Four patients (7.1%) experienced mild adverse events, such as injection site reaction, upper respiratory tract infection, and headache. Conclusion This study reconfirmed the efficacy and safety of guselkumab in Korean patients with moderateto-severe psoriasis.

Epidermal cysts are the most common cutaneous cysts that originate from the hair follicles. Therefore, they are rarely found in areas without hair follicles, such as the palms, soles, and subungual areas. Herein, we reported two cases of subungual epidermoid implantation cysts. The first patient was a 52-year-old male who presented with onycholysis and a subungual white mass on the middle fingernail of the right hand. The second patient was a 67-year-old male who presented with an erythematous patch and swelling of the proximal nail fold of the right thumb. Ultrasonography revealed bone erosion and a round-to-elliptical mass with internal avascularity. Heterogeneous echogenicity and internal echogenic foci were detected in both patients. After nail avulsion, a skin-colored mass was observed. Histopathological examination revealed typical epidermal cysts in both patients. Herein, we report two rare cases of subungual epidermoid implantation cysts.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin’s lymphoma accounting for approximately one-third of all cases. DLBCL can present as a lymph node or extranodal tumor. Cavernous sinus (CS) is a small but complex structure in which various arteries, sympathetic plexuses, and cranial nerves are passing through. Cavernous sinus syndrome (CSS) results from any disease process that affects CS including tumor, vascular disease, infection, or inflammation. Herein, we report a case of extranodal DLBCL diagnosed by skin biopsy presenting as CSS. A 58-year-old male presented with a 3-week-old, gradually growing subcutaneous nodule on the left upper lip. He also suffered from ptosis, ophthalmoplegia, diplopia, and headache confined to the right side for 3 months. Histopathologic examination of the left upper lip showed dense dermal infiltration of atypical large tumor cells resembling centroblasts and immunoblasts. Immunohistochemistry studies revealed that the tumor cells were positive for CD20, BCL2, BCL6, MUM1, and MYC. After additional radiologic evaluation with positron emission tomography-computed tomography (PET-CT), brain magnetic resonance imaging, and orbital CT, he was finally diagnosed with extranodal DLBCL involving the right CS, oculomotor muscles, and left upper lip.

Background: Dupilumab is a human monoclonal antibody against interleukin-4 receptor α. Several clinical trials have demonstrated the rapid and excellent therapeutic effects of dupilumab. Although a growing number of studies have reported data on the real-world efficacy and safety of dupilumab for the treatment of atopic dermatitis, data on real-world experiences in Korea are limited. Objective: To evaluate the real-world efficacy and safety of dupilumab for the treatment of moderate-to-severe atopic dermatitis in Korean patients. Methods: This was a retrospective, single-center study. A total of 179 patients treated with dupilumab for at least 16 weeks were enrolled in this study. Based on electronic medical records, the clinical characteristics, Eczema Area and Severity Index (EASI) score, and adverse events were investigated. Results: The mean baseline EASI score (26.5±7.2) significantly decreased at weeks 16, 40, 52, and 112 (p＜0.05). All and 55.2% of patients achieved EASI75 and EASI90 responses at week 52, and all and 75.0% of patients achieved EASI75 and EASI90 responses at week 112, respectively. Common adverse events were facial erythema (31.8%), conjunctivitis (24.0%), and herpes simplex virus infection (11.2%). Three serious adverse events of severe conjunctivitis, mycosis fungoides, and mesenteric venous thrombosis resulted in discontinuation of dupilumab. Conclusion Dupilumab was effective in real-world clinical practice with a favorable safety profile in Korean patients with moderate-to-severe atopic dermatitis.

Background: Risankizumab, human immunoglobulin G1λ monoclonal antibody, selectively blocks the p19 subunit of interleukin-23-mediated signaling pathway. Risankizumab has emerged as an effective and well-tolerated therapeutic option for moderate-to-severe psoriasis. However, real-world data on treatment outcomes of risankizumab in Korean patients with psoriasis are limited. Objective: To investigate the efficacy and safety of risankizumab in Korean patients with moderate-to-severe plaque psoriasis. Methods: We retrospectively reviewed patients with moderate-to-severe psoriasis who were treated with risankizumab in our hospital from July 2020 to December 2022. A total of 45 patients with psoriasis who were treated with risankizumab for at least 16 weeks were included in this study. Patient demographics, Psoriasis Area and Severity Index (PASI) scores, Investigator’s Global Assessment scores, and adverse events were assessed. Results: The mean baseline PASI score (13.1±7.7) was significantly decreased after 16 weeks of risankizumab treatment (0.9±1.4) (p＜0.05). Of the 45 patients, 40 showed a PASI 90 response at the last follow-up visit. No serious adverse events were observed. Three patients (6.7%) experienced mild adverse events such as injection site reaction, easy bruising, and headache. Conclusion Our real-world data demonstrated that risankizumab treatment is effective and safe in Korean patients with moderate-to-severe plaque psoriasis.