Background: Eccrine poroma (EP) is a benign adnexal neoplasm that can be pigmented in 17% of cases. Four histopathological variants of EP exist. Dermoscopically, EP can mimic many other skin neoplasms. Objectives: To provide a dermoscopic–histopathological correlation of EP, classifying the clinical and dermoscopic features of EPs on the basis of their histopathological subtype, in an attempt to better characterize these entities. Patients and Methods: A single-center retrospective study was conducted. Clinical data were collected; patients were classified on the basis of the 4 histopathological variants of EPs. Dermoscopic images were reviewed. A dermoscopic–histopathological correlation was performed, and the results were compared with literature data. Results: Twenty-six lesions were included, both pigmented and nonpigmented. Three of the 4 histopathological variants were identified. Different dermoscopic features were observed for each distinct histopathological subtype of EP. The lesions mimicked different types of other skin neoplasms, in particular: nonpigmented hidroacanthoma simplex resembled nonmelanoma skin cancer; pigmented hidroacanthoma simplex appeared like a seborrheic keratosis or a solar lentigo; EPs sensu stricto presented as pink nodules if nonpigmented and were similar to seborrheic keratosis if pigmented; dermal duct tumors appeared as pigmented nodular lesions. Conclusions: Distinct dermoscopic features appeared to be recurrent in each histopathological variant. Dermoscopy can provide important clues for the diagnosis of EP; the final diagnosis is allowed by histopathology. To achieve a correct diagnosis of EP, because of its clinical and dermoscopic variability, surgical excision is recommended.

Background: vulvar intraepithelial neoplasia is a non-invasive precursor lesion found in 50–70% of patients affected by vulvar squamous cell carcinoma. In the past, radical surgery was the standard treatment for vulvar intraepithelial neoplasia, however, considering the psychological and physical morbidities related to extensive surgery, several less aggressive treatment modalities have been proposed since the late 1970s. Photodynamic therapy is an effective and safe treatment for cutaneous non-melanoma skin cancer, with favorable cosmetic outcomes. Methods: in the present paper, the results of selected studies on photodynamic therapy in the treatment of vulvar intraepithelial neoplasia are reported and discussed. Results: Overall, complete histological response rates ranged between 20% and 67% and symptom response rates ranged between 52% and 89% according to different studies and case series. Conclusions: the real benefit of photodynamic therapy in the setting of vulvar intraepithelial neoplasia lies in its ability to treat multi-focal disease with minimal tissue destruction, preservation of vulvar anatomy and excellent cosmetic outcomes. These properties explain why photodynamic therapy is an attractive option for vulvar intraepithelial neoplasia treatment.

Conflict of interest: the authors declare that they have no conflicts of interest.

Background: Cutaneous melanoma (CM) poses significant diagnostic challenges due to its biological heterogeneity and the subjective interpretation of histopathologic criteria. While early and accurate diagnosis remains critical for patient outcomes, conventional pathology is limited by interobserver variability and diagnostic ambiguity, especially in borderline lesions. Objective: This narrative review explores the integration of digital pathology (DP) and artificial intelligence (AI)—including deep learning (DL), machine learning (ML), and interpretable models—into the histopathologic workflow for CM diagnosis. Methods: We systematically searched PubMed, Scopus, and Web of Science (2013–2025) for studies using whole slide imaging (WSI) and AI to assist melanoma diagnosis. We categorized findings across five domains: WSI-based classification models, feature extraction (e.g., mitoses, ulceration), spatial modeling and TIL analysis, molecular prediction (e.g., BRAF mutation), and interpretable pipelines based on nuclei morphology. Results: We included 87 studies with diverse AI methodologies. Convolutional neural networks (CNNs) achieved diagnostic accuracy comparable to expert dermatopathologists. U-Net and Mask R-CNN models enabled robust detection of critical histologic features, while nuclei-level analyses offered explainable classification strategies. Spatial and morphometric modeling allowed quantification of tumor–immune interactions, and select models inferred molecular alterations directly from H&E slides. However, generalizability remains limited due to small, homogeneous datasets and lack of external validation. Conclusions: AI-enhanced digital pathology holds transformative potential in CM diagnosis, offering accuracy, reproducibility, and interpretability. Yet, clinical integration requires multicentric validation, standardized protocols, and attention to workflow, ethical, and medico-legal challenges. Future developments, including multimodal AI and integration into molecular tumor boards, may redefine diagnostic precision in melanoma.

Background: Cutaneous melanoma (CM) is one of the most lethal tumors among skin cancers and its incidence is rising worldwide. Recent data support the role of microRNAs (miRNAs) in melanoma carcinogenesis and their potential use as disease biomarkers. Methods: We quantified the expression of miR-146a-5p and miR-21-5p in 170 formalin-fixed paraffin embedded (FFPE) samples of CM, namely 116 superficial spreading melanoma (SSM), 26 nodular melanoma (NM), and 28 lentigo maligna melanoma (LMM). We correlated miRNA expression with specific histopathologic features including Breslow thickness (BT), histological subtype, ulceration and regression status, and mitotic index. Results: miR-146a-5p and miR-21-5p were significantly higher in NM compared to SSM and LMM. The positive correlation between miR-146a-5p and miR-21-5p expression and BT was confirmed for both miRNAs in SSM. Considering the ulceration status, we assessed that individual miR-21-5p expression was significantly higher in ulcerated CMs. The increased combined expression of the two miRNAs was strongly associated with ulceration (p = 0.0093) and higher mitotic rate (≥1/mm²) (p = 0.0005). We demonstrated that the combination of two-miRNA expression and prognostic features (BT and ulceration) can better differentiate cutaneous melanoma prognostic groups, considering overall survival and time-to-relapse clinical outcomes. Specifically, miRNA expression can further stratify prognostic groups among patients with BT ≥ 0.8 mm but without ulceration. Our findings provide further insights into the characterization of CM with specific prognostic features. The graphical abstract was created with BioRender.com.

Background/objectives: Despite advancements in early diagnosis and clinical practices guided by standardized care protocols, Merkel cell carcinoma (MCC) is marked by an unfavorable prognosis with a 5-year relative survival rate of 65%, based primarily on data collected prior to the introduction of immunotherapy. Regional nodal metastases affect 40–50% of MCC patients, while approximately 33% experience distant dissemination. Among these, bone and bone marrow metastases are particularly notable, although the characteristics and clinical implications of this metastatic disease in MCC remain poorly understood. Methods: A comprehensive review was conducted using the Medline database (via PubMed) up to January 2025. The search strategy included the string “(Merkel cell carcinoma AND (bone OR marrow))”. Results: A total of 1133 (69.3% male and 30.7% female) patients diagnosed with advanced MCC were collected. The median (IQR) age at diagnosis was 67.5 (12.65) years old. Overall, 201 (20.8%) cases of bone and/or bone marrow metastases were identified and linked to a primary known MCC in 75.7% of cases. Bone metastases (BMs) appear as the third most common metastatic site, following the liver (second) and lymph nodes (first). They show mixed biological and radiological behavior, with a marked preference for the axial skeleton over the appendicular one. Addressing the characteristics of metastatic bone disease, neurological symptoms were the most documented, whereas bone marrow involvement and leukemic spread seemed to be primarily related to immunosuppression. Multimodal treatment strategies, including platinum-based chemotherapy and radiotherapy, were the primary approaches adopted, reflecting therapeutic practices from the pre-immunotherapy era. Conclusions: The pattern of metastatic spread in MCC differs among studies, with the bones resulting as the third most common site of distant spread. Excluding head and neck MCC, which seems to be more regularly associated with liver metastases, the relationship between the primary tumor site and the development of bone or bone marrow metastases appears inconsistent. Overall, BMs mostly correlated with advanced MCC stages and poorer survival outcomes, with a median overall survival (OS) of 8 months (range 12.75–4). The integration of international guidelines, evolving evidence from clinical trials, and the expanding role of immune checkpoint inhibitors (ICIs) will contribute to improving systemic disease control and enhance patient care.