A 60－year－old man had been receiving oral cyclosporine at a local clinic for chronic eczema for 10 years. Three years earlier, a black macule had appeared on his vertex scalp and gradually enlarged ; however, he did not seek medical attention. Two years prior, it measured 2 cm ; however, its rapid growth over the following year led him to consult the referring physician. Partial biopsy suggested malignant melanoma, and the patient was referred to our department. During his first visit, we observed a coalescent black－and－erythematous nodule on the vertex and an irregularly bordered black patch contiguous with a red nodule on the right temporal scalp. Two punch biopsies of the temporal lesion confirmed malignant melanoma. As immunosuppressive therapy is known to increase the risk of cutaneous malignancies and long－term cyclosporine use is becoming more common, we report this case with a review of the literature.[Skin Cancer (Japan) 2025 ; 40 : 109－113]

A 63－year－old woman presented with a 5－year history of a brownish lesion beneath her left breast. Examination revealed a well－demarcated, irregularly shaped patch measuring 54×35 mm. A skin biopsy confirmed extramammary Paget’s disease (EMPD). Mammography, breast ultrasonography, and contrast－enhanced magnetic resonance imaging showed no intramammary lesions, and computed tomography revealed no metastases. Local excision with a 1 cm margin was performed. Histopathological examination revealed atypical epithelial cells with clear cytoplasm and prominent nucleoli extending from the epidermis to the dermis. Immunohistochemical staining was positive for CK7 and GCDFP－15, and negative for S－100, Melan－A, and p63. Glandular structures suggestive of mammary ductal－lobular components were identified in the subcutaneous adipose tissue beneath the tumor. Based on histopathological and immunohistochemical findings, the lesion was diagnosed as ectopic EMPD, possibly arising from an accessory mammary gland. No recurrence or metastasis was detectable 6 months after surgery.[Skin Cancer (Japan) 2025 ; 40 : 114－120]

An 18－year－old female presented with a purplish nodule on her left thigh 1 year earlier. She underwent resection by her previous doctor and was diagnosed with dermatofibrosarcoma protuberans (DFSP). A 2 cm margin from the mass and the inferior floor with an intrinsic fascia were resected. Histopathologically, spindle－shaped cells proliferated irregularly in the dermis, creating a honeycomb－like appearance in the subcutaneous fat, and more than 80% of the tumor showed mucinous changes. Immunohistochemical staining was positive for CD34 and negative for factor ⅩⅢa. Therefore, the patient was diagnosed with myxoid DFSP. The incidence of DFSP in patients aged < 20 years is approximately 1 per 1 million, with myxoid DFSP accounting for 4% of all DFSPs. Herein, we report a case of myxoid DFSP in a young adult, an exceedingly rare occurrence, along with a review of the literature.[Skin Cancer (Japan) 2025 ; 40 : 121－126]

An 89－year－old male presented with an enlarging oval mass in the right posterior neck that had been first noticed two months prior to the initial consultation. On examination, a 25－mm－sized reddish lesion with surface erosion was observed. Biopsy revealed diffuse proliferation of small－to medium-sized and some large atypical lymphocytes, positive for CD8 and CD30 throughout the dermis and subcutaneous fat, with mild epidermotropism. Immunohistochemistry revealed that the atypical cells were partially positive for granzyme B and negative for ALK. Southern blot analysis demonstrated monoclonal rearrangements of T－cell receptor β chain and γ chain. No involvement of lymph nodes or other organs was detected by computed tomography. Given the solitary indolent lesion and characteristic histopathological findings, a diagnosis of CD8－positive primary cutaneous anaplastic large cell lymphoma was made. Local radiotherapy was administered, which resulted in regression of the tumor after three months.[Skin Cancer (Japan) 2025 ; 40 : 127－132]

Case 1 involved a 69－year－old male who presented with a reddish penile plaque. Case 2 involved a 78－year－old male with a reddish scrotal nodule. Histopathological examination in both cases revealed full－thickness epidermal dysplasia characterized by abnormal keratinocytes and the presence of clumped cells. The lesions were completely excised under local anesthesia. DNA was extracted from paraffin－embedded tissue samples of excised lesions, and HPV－DNA testing was conducted. HPV type 16 was detected in Case 1, and HPV type 51 was detected in Case 2. Immunohistochemical analysis revealed strong expression of p16 protein in both cases, whereas p53 protein expression was negative. In cervical cancer, p16 overexpression is widely recognized as a surrogate marker of HPV infection. However, in Bowen’s disease, p16 overexpression does not reliably correlate with HPV infection. Recent studies suggest that the absence of p53 expression, rather than p16 status, may be more closely associated with HPV－related Bowen disease.[Skin Cancer (Japan) 2025 ; 40 : 133－137]

A 37－year－old male with Fanconi anemia presented with a red plaque on the right scrotum. Surgical resection with a 6 mm margin revealed histopathological features of Bowen’s disease, which is characterized by full－thickness proliferation of atypical keratinocytes. High－risk human papilloma virus (HPV) was not detected. Fanconi anemia is a genetic disorder involving defects in the FA/BRCA DNA repair pathway and is associated with an increased risk of cancer. Although cutaneous squamous and basal cell carcinomas are commonly reported in patients with Fanconi anemia, Bowen’s disease is rare. Previously, these cases were typically linked to sun－exposed areas or a high－risk HPV infection. This case is notable because the lesion developed at a sun－protected site and it was HPV－negative. These findings highlight the need for vigilant monitoring of patients with Fanconi anemia because Bowen’s disease may arise in atypical locations and it is independent of HPV infection.[Skin Cancer (Japan) 2025 ; 40 : 138－142]