Pilomatricoma: Clinical, Dermoscopic Findings and Management in 55 Pediatric Patients and Concise Review of the Literature with Special Emphasis on Dermoscopy.

INTRODUCTION: Pilomatricoma is a benign adnexal dermal or subcutaneous tumor derived from immature hair matrix cells. OBJECTIVES: The aim of our study is to evaluate clinical and dermoscopic features of pilomatricomas, with a specific focus on pediatric lesions, and to provide a concise review of the existing literature. METHODS: A single-center retrospective study was undertaken on 55 patients with a histopathological diagnosis of pilomatricoma referred to the Dermatology Unit, University of Bologna, Bologna, Italy, between 2005 and 2023. Pilomatricomas were retrospectively evaluated relying on clinical and dermoscopic images. A PubMed search was conducted. All the relevant research up to July 31, 2023, was reviewed. We classified the cases as "typical" or "atypical" based on whether they were suspected of being pilomatricomas or not. RESULTS: A total of 55 children with pilomatricomas were observed and studied. Two patients presented with 2 pilomatricomas, leading to the identification of 58 pilomatricomas. 'Typical' pilomatricomas were observed in 79% of cases as nodular and pigmented lesions with one or more colors, ranging from blue-gray to red to yellow/white, evident on clinical examination and even better on dermoscopy. In 21% of cases, pilomatricomas presented in an 'atypical' form, which did not allow for a well-founded suspicion, placing them in differential diagnosis with other lesions and therefore requiring histological examination. CONCLUSIONS: According to our case series and systematic review of the literature, clinical appearance and dermoscopy may be sufficient to diagnose or suspect pilomatricoma in around 80% of cases, while histological examination is necessary to confirm the diagnosis in the remaining 20% of cases.

Eruptive Non-melanoma Skin Cancers/Squamous Atypia Following Skin Surgery. Report of Two New Cases, Concise Review of the Literature With Special Emphasis on Treatment Options.

Introduction: Eruptive cutaneous squamous cell carcinomas (ESCC), eruptive squamous atypia (ESA) and eruptive keratoacanthomas (EKA) are different terms used to describe the occurrence of multiple cutaneous squamous neoplasms after skin surgery, laser treatment, traumas, such as tattoos, and local or systemic medical treatments. ESCC have been reported to arise at the sites of skin surgery, including the area affected by the primary tumor and split thickness skin graft (STSG) donor and recipient sites. Objectives: The aim of this study is to report 2 additional cases of ESCC after skin surgery and make a critical revision of the literature, analyzing the clinical, histological features and outcomes of ESCC after cutaneous surgery. Methods: Up to August 2021, according to our systematic review of the literature, we have collected 19 published articles and a total of 34 patients, including our 2 cases. Results: The results of this review highlight five red flags that clinicians should consider: (i) lower and upper limbs represent the cutaneous site with the highest risk, representing 83,78% of the cases in the literature; (ii) the median time to onset of ESCC is approximately 6 weeks; (iii) primary cutaneous squamous cell carcinomas were completely excised with free margins on histologic examination in the totality of the cases of the literature, and therefore ESCC should not be considered recurrences; (iv) any surgical technique involves a risk to promote ESCC; (v) treatment of ESCC includes medical treatment, surgery or combined surgical and medical treatment. Conclusions: This review highlights 5 red flags which could support clinicians in the diagnosis and management of ESCC after skin surgery.

Machine learning-based clinical outcome prediction in surgery for acromegaly.

PURPOSE: Biochemical remission (BR), gross total resection (GTR), and intraoperative cerebrospinal fluid (CSF) leaks are important metrics in transsphenoidal surgery for acromegaly, and prediction of their likelihood using machine learning would be clinically advantageous. We aim to develop and externally validate clinical prediction models for outcomes after transsphenoidal surgery for acromegaly. METHODS: Using data from two registries, we develop and externally validate machine learning models for GTR, BR, and CSF leaks after endoscopic transsphenoidal surgery in acromegalic patients. For the model development a registry from Bologna, Italy was used. External validation was then performed using data from Zurich, Switzerland. Gender, age, prior surgery, as well as Hardy and Knosp classification were used as input features. Discrimination and calibration metrics were assessed. RESULTS: The derivation cohort consisted of 307 patients (43.3% male; mean [SD] age, 47.2 [12.7] years). GTR was achieved in 226 (73.6%) and BR in 245 (79.8%) patients. In the external validation cohort with 46 patients, 31 (75.6%) achieved GTR and 31 (77.5%) achieved BR. Area under the curve (AUC) at external validation was 0.75 (95% confidence interval: 0.59-0.88) for GTR, 0.63 (0.40-0.82) for BR, as well as 0.77 (0.62-0.91) for intraoperative CSF leaks. While prior surgery was the most important variable for prediction of GTR, age, and Hardy grading contributed most to the predictions of BR and CSF leaks, respectively. CONCLUSIONS: Gross total resection, biochemical remission, and CSF leaks remain hard to predict, but machine learning offers potential in helping to tailor surgical therapy. We demonstrate the feasibility of developing and externally validating clinical prediction models for these outcomes after surgery for acromegaly and lay the groundwork for development of a multicenter model with more robust generalization.