Congenital Smooth Muscle Hamartoma Characterized by Hypopigmented Appearance / 대한피부과학회지

Congenital smooth muscle hamartoma is a benign proliferation of smooth muscles within the dermis. The classic form presents as well-defined, skin-colored, or hyperpigmented plaques associated with hypertrichosis. However, there have been reports of atypical forms, including a follicular spotted appearance, linear atrophic plaques, and morphea-like forms. In such cases, distinguishing congenital smooth muscle hamartomas from other cutaneous diseases can be challenging. Herein, we report on a 16-month-old boy who presented with a hypopigmented patch and hypertrichosis on his back since birth. Histopathological examination revealed mild acanthosis and well-defined smooth muscle bundles haphazardly oriented in the dermis. These bundles stained positively with Masson’s trichrome stain. Based on these findings, a definitive diagnosis of congenital smooth muscle hamartoma was established. In conclusion, an exceptionally rare case of congenital smooth muscle hamartoma with a hypopigmented appearance is reported.

Effectiveness and Safety of Low-Dose Oral Minoxidil in Female Pattern Hair Loss:A Single-Center Study of 44 Patients / 대한피부과학회지

Background@#Female-pattern hair loss (FPHL) is characterized by diffuse hair thinning in the mid-frontal scalp and increased hair shedding. Although the use of low-dose oral minoxidil (LDOM) is increasing significantly in Korea, data on its use are limited. @*Objective@#To determine the efficacy and safety of LDOM in Korean patients with FPHL. @*Methods@#This retrospective, single-center study was conducted at Pusan National University Hospital. The study included female patients with pattern hair loss who received treatment with LDOM at 1.25 mg/d for a minimum of 6 months in combination with other treatments. Patients were eligible for LDOM addition if their previous treatments showed a limited response and the previous treatment regimen remained unchanged throughout the evaluation period. Clinical response to treatment was evaluated using the Sinclair hair loss severity scale. @*Results@#The study included 44 females with FPHL. Before treatment, the mean Sinclair scale score was 2.77, which decreased to 2.27 after treatment. By the 3rd month, one patient (2.3%) experienced worsening, while seven patients (15.9%) showed slight improvement. By the 6th month, the treatment response was as follows: stabilization in 30 patients (68.2%), slight improvement in 13 patients (29.5%), and substantial improvement in one patient (2.3%). Adverse effects, predominantly hypertrichosis, were observed in nine patients. All adverse effects improved upon discontinuation of LDOM and no life-threatening adverse effects were observed during the study. @*Conclusion@#This study provides evidence that LDOM can be an effective therapeutic option with a good safety profile for FPHL.

Two Cases of Mycosis Fungoides Diagnosed during Dupilumab Treatment / 대한피부과학회지

Dupilumab, a human monoclonal antibody targeting the interleukin-4 receptor α, has exhibited rapid and remarkable therapeutic efficacy in numerous clinical trials focusing on moderate-to-severe atopic dermatitis and prurigo nodularis. Nonetheless, instances of mycosis fungoides have been reported in patients undergoing dupilumab treatment for atopic dermatitis. We present two cases: a 36-year-old woman and a 64-year-old man who presented to our dermatology clinic with erythematous papules and plaques. Following skin biopsy, both patients were diagnosed with chronic eczematous dermatitis with prurigo. Erythematous plaques notably increased after 9 months and 1 month of dupilumab treatment, respectively. Subsequent biopsies confirmed histopathological markers consistent with mycosis fungoides. The first patient underwent chemotherapy for lymph node metastasis, while the second received oral acitretin, narrow-band ultraviolet B, and topical corticosteroids.

Multiple Cutaneous Rosai-Dorfman Disease on the Face Treated by Electrosurgery / 대한피부과학회지

Cutaneous Rosai-Dorfman disease (RDD) is a rare, benign condition mainly affecting the lymph nodes and sometimes involving the skin. RDD is notorious for its poor response to medication, and surgery is often the preferred treatment option for limited lesions. Herein, we present a case of cutaneous RDD in a 49-year-old woman with multiple facial nodules that showed minimal response to treatment with steroids, isotretinoin, and methotrexate.The diagnosis of cutaneous RDD was confirmed based on histopathological examination. The patient showed minimal response to medication; however, electrosurgery resulted in a relatively good cosmetic response. The present case demonstrates that electrosurgery can be an effective treatment option for cutaneous RDD, especially in case of patients with multiple lesions. The rarity of this disease and the limited reports on its management highlights the need for further research on the efficacy of different surgical modalities for cutaneous RDD.

A Novel Mutation in the MBTPS2 Gene Resulting in Ichthyosis Follicularis, Atrichia, and Photophobia Syndrome

Ichthyosis follicularis, atrichia, and photophobia (IFAP) syndrome is a rare genetic disorder caused by mutations in the MBTPS2 gene. It is characterized by ichthyosis and alopecia from birth. Photophobia may be present in infancy or early childhood. Its mode of inheritance is X-linked recessive; thus, it mostly affects male. The disease severity varies, ranging from mild cases limited to the skin to the severe variant involving multiple extracutaneous features. A 7-year-old boy presented with scanty hair on scalp and eyebrows at birth. On physical examination, scaly patches were observed on the whole body and spiky follicular hyperkeratotic papules were observed on the face and trunk. He also suffered from severe photophobia. Histopathological examination of the scalp showed miniaturized hair follicles without perifollicular fibrosis. Genetic analysis revealed a novel mutation in the MBTPS2 gene which was a homozygous missense mutation of c.245T>C leading to an amino-acid substitution from phenylalanine to serine (p.Phe82Ser). We diagnosed this patient with IFAP syndrome. To date, 25 pathogenic MBTPS2 gene mutations have been identified. To our knowledge, c.245T>C is a novel homozygous missense mutation in the MBTPS2 gene, which has not been reported in Human Gene Mutation Database, ClinVar Database, and Leiden Open Variation Database. Previous reports suggested genotype-phenotype correlations in the MBTPS2 gene mutations. Supported by a previous notion that genotype correlates with phenotype, this novel mutation can be a predictive factor for the mild form of IFAP syndrome, restricted to the classic symptom triad.

CD30＋ Large-Cell Transformation of Mycosis Fungoides Treated with Brentuximab Vedotin / 대한피부과학회지

Large-cell transformation of mycosis fungoides (LCT-MF) is an advanced stage of primary cutaneous T-cell lymphoma with a poor prognosis. Therapeutic options for these patients are often limited, and so far, they are not promising. An 81-year-old woman with a previous history of mycosis fungoides presented with aggravation of generalized erythematous scaly patches and new onset of ulcerated tumor on the abdomen for 3 months.Histopathological examination revealed a dense dermal infiltrate composed of atypical large lymphocytes. Immunohistochemically, the tumor cells were positive for CD30 expression. A diagnosis of CD30＋ LCT-MF was established. She was intensively treated with methotrexate (1 month), acitretin (1 month), and rituximab with dose-modified cyclophosphamide, doxorubicin, and prednisone (1 cycle). Despite such treatments, the improvement was minimal. Subsequently, the patient was started on brentuximab vedotin, 1.8 mg/kg intravenously once every 3weeks. She responded well to brentuximab therapy, and the skin lesions completely subsided within 12 weeks of treatment.