A 72－year－old woman presented to our department with a tumor on the right lumbar region in January 2019. The patient recounted that she had a black spot in that same region since childhood. An excisional biopsy was performed in November of the same year, and a pathological diagnosis of malignant melanoma was made. Her PET/CT also revealed metastasis to the right inguinal region and right external iliac lymph node, and in December, she underwent right inguinal region, external iliac bone, and closed lymph node dissection (Stage IIIC). Oral administration of Tafinlar and Mekinist was initiated as postoperative adjuvant therapy ; however, the patient complained of respiratory distress six months after initiation of oral administration, and a detailed examination revealed a decrease in her cardiac function. She was subsequently diagnosed with drug－induced heart failure, prompting discontinuation of Tafinlar and Mekinist, and hospitalization for the management of her symptoms. Herein, we report a case of drug－induced heart failure caused by oral administration of Tafinlar and Mekinist, including certain bibliographical considerations for such cases.[Skin Cancer (Japan) 2021 ; 36 : 149－152]

A 28－year－old woman with a history of Hashimoto’s disease visited us due to a rash with pain in the vulva. At the first consultation, erosive lesions, white wart－like plaques, and brown papules from the vaginal vestibule to the labia majora were observed. A diagnostic skin biopsy was performed, with the specimen including all of the above sites. Histopathological findings revealed atypical keratinocytes, fission images, and clumping cells in the entire epidermis in the erosive lesions and white wart－like plaques ; brown papules showed similar but slightly atypical findings. Epidermal cells were diffusely positive including the cytoplasm at both sites in almost all layers. The above findings were suggestive of Bowen’s disease and bowenoid papulosis of the vulva in the young woman. Lesion excision with a 5－mm margin was performed for treating the patient.[Skin Cancer (Japan) 2021 ; 36 : 153－157]

An 85－year－old male was admitted to our hospital with a large tumor on his left shoulder. The tumor was first noticed when he was 60 years old and had gradually grown to 6 cm × 6 cm × 7 cm in size at the time of his consultation. Some signs of necrosis and infection were noticed. Surgical excision, including a margin of 1.5 cm, was performed. Histopathological diagnosis revealed dermatofibrosarcoma protuberans. Thus, further extensive resection with a margin of 2 cm extending from the initial surgical site was performed including partial resection of the acromion. The defect was reconstructed with a superficial cervical artery flap. During the 15－month follow－up period, no recurrence or contracture were observed, and the flap survived successfully.[Skin Cancer (Japan) 2021 ; 36 : 158－163]

An 83－year－old man presented with a left－sided, forehead tumor, noticed to be a gradually expanding, black－brown spot for 10 years. Clinical examination showed a 35×25 mm dark brown macule with central ulceration ; clinical diagnosis was basal cell carcinoma. Histopathological examination of the biopsy showed features of both basal, and squamous cell carcinoma. The tumor was surgically excised, with a 1 cm surgical margin. Ber－EP4 staining was focally positive within the tumor, which was diagnosed as basosquamous cell carcinoma. The defect was closed using a full－thickness skin graft. Six months after the operation, no local recurrence, lymph node or organ metastasis was detected with a full－body computed tomography scan.[Skin Cancer (Japan) 2021 ; 36 : 164－167]

Mixed skin tumors, consisting of mesenchymal and epithelial tissues, are rare. They are most frequently located in the head and neck region. We report the case of a mixed skin tumor arising from the auricular region, along with a review of the related literature. The patient was a 57－year－old man. He noted a gradual enlarging skin tumor in the auricular region four months prior to his first visit. A trepanation biopsy revealed a mixed skin tumor. Complete excision was performed under local anesthesia, and the histopathological findings of the excised specimen confirmed the diagnosis. The patient had a favorable prognosis, and local recurrence did not occur three months following the surgery.[Skin Cancer (Japan) 2021 ; 36 : 168－172]

Among malignant skin tumors, cutaneous malignant melanoma has poor prognosis, and high risk of metastasis. Sentinel Lymph Node Biopsy (SLNB) is a minimally invasive procedure, for accurate staging and consideration of lymph node dissection. We examined the clinical significance and effect of SLNB, by analyzing 10－year results of treatment, for cutaneous malignant melanoma at Tokushima University Hospital ; SLNB was effective in determining prognosis. Despite lymph node dissection, no effect in improving prognosis was observed. Currently, various molecular－targeted drugs and immune checkpoint inhibitors have appeared as treatments for malignant melanoma, and their therapeutic strategies are still advancing. In the future, clinical trials with adjuvant therapy and SLNB or Complete Lymph Node Dissection, should be conducted to improve prognosis.[Skin Cancer (Japan) 2021 ; 36 : 173－179]