Schwannoma, also known as neurilemmoma, is a benign neoplasm of Schwann cells of the cranial or peripheral nerve sheath. Scalp involvement has been reported in 25% of patients with extracranial head and neck schwannomas, which can be misdiagnosed clinically as epidermal cyst or lipoma. In this article, we report a 32-year-old male presenting with a slow-growing painful subcutaneous mass on the left occipital scalps without any neurological symptoms. Pathological findings confirmed the diagnosis of schwannoma, and surgical removal resulted in the resolution of pain and lack of recurrence.

UNASSIGNED: The Spitz nevus (SN) is an acquired melanocytic neoplasm composed of epithelioid and/or spindle cells, which tends to develop in childhood. In pediatric patients, it is usually located on the face and neck. Unusual locations have been found in the literature, such as the penis, mouth, and tongue, as well as 2 cases of ungual SN.
UNASSIGNED: A 15-year-old male evaluated for dark brown-black longitudinal melanonychia that covered 40% of the nail, with pseudo-Hutchinson\'s sign, of 1 year of evolution.
UNASSIGNED: The SN accounts for 1% of the melanocytic neoplasms. In the present paper, we show the third case of ungual SN never previously disclosed, which presents a zigzag pattern reported in the literature for its association with the pediatric population.

(1) Background: Endocrine Mucin-Producing Sweat Gland Carcinoma (EMPSGC) is a rare, low-grade, neuroendocrine-differentiated, cutaneous adnexal tumor, officially recognized by the World Health Organization (WHO) Skin Tumors Classification in 2018 as a separate entity and homologue of endocrine ductal carcinoma in situ (eDCIS)/solid papillary carcinoma of the breast. Although it is more frequent in the female sex, between 60 and 70 years old, in the peri-orbital region, EMPSGC has also been described in the male sex, in subjects under 60 and over 80, and in extra-eyelid localizations (cheek, temple, scalp), but also in extra-facial localizations (chest and scrotum). (2) Methods: We present the clinical case of a 71-year-old woman with an undated lesion of the scalp, which presented as a nodule, skin-colored, and 2.5 cm in maximum diameter. We also conduct a comprehensive literature review from 1997 to the end of 2022, consulting PubMed, Scopus, Web of Science (WoS), and Google Scholar using the following keywords: \"Endocrine mucin-producing sweat gland carcinoma\" and/or \"EMPSGC\" and/or \"skin\" and \"cutaneous neoplasms\". In addition, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 253 patients were recorded; 146 were females (57.7%) and 107 were males (42.2%). The vast majority of the lesions were in the eyelids (peri-ocular region), and only a minority of cases involved the cheeks, supra-auricular, retro-auricular, and occipital region, with very rare cases in the scalp, to which the present is also added. (4) Conclusions: The morphological and immunophenotypical features are essential both for the correct diagnosis and to be able to classify this lesion among the corresponding eDCIS/solid papillary carcinoma of the breast, with neuroendocrine differentiation. Recent papers have attempted to shed light on the molecular features of EMPSGC, and much remains to be conducted in the attempt to subtype the molecular profiles of these entities. Future studies with large case series, and especially with molecular biology techniques, will be needed to further add information about EMPSGC and its relationship in the PCMC spectrum.

Fibrofolliculoma is a benign, perifollicular, connective tissue tumor that usually arises in the form of multiple lesions; it is rarely seen as a solitary lesion. The lesions are clinically asymptomatic, 2 to 4 mm skin-colored, soft dome-shaped papules. Here, we report a patient who visited our hospital with a palpable lesion on the nasal septum. The lesion did not cause pain upon palpation, and nasal endoscopy confirmed an irregular wart-like lesion measuring 6 × 6 mm in the left anterior nasal septum near the columella. Other otolaryngology findings were normal, and there were no similar lesions in other parts of the body. None of the patient\'s family members were known to have had such lesions. An excisional biopsy was performed on the mass for removal of the lesion, and histological examination confirmed the lesion as fibrofolliculoma. We report the first case of solitary fibrofolliculoma in the nasal septum in a healthy 62-year-old woman along with a review of the relevant literature.

We present a case of a 47-year-old female with a swelling on her scalp that was at first thought to be trichilemmal cysts. After two years, she returned to her general practitioner with a larger scalp mass. Following a biopsy, histological analysis revealed dermatofibrosarcoma protuberans (DFSP). She then had the tumor completely removed, resulting in clean margins.

Pilomatricoma, formerly known as calcifying epithelioma of Malherbe, is a rare, benign, annexic skin tumor developed from the cells of the pilar matrix. The cure without recurrence is the rule after complete surgical excision. Clinical diagnosis is challenging. Actually, differential diagnosis include malignant pilomatricoma or trichomatrical carcinoma with significant aggressive potential. However, the diagnosis of pilomatricoma must remain clinical and be confirmed histologically. We report the rare case of a pilomatricoma, in an unusual location in the thigh.

Subungual melanomas are rare neoplasms that tend to debut as longitudinal melanonychia. They are primarily found in patients over 60 years of age and are usually diagnosed late, representing a diagnostic challenge. We present a case report of a 59-year-old female Hispanic patient who initially presented with melanonychia and was eventually diagnosed with subungual melanoma in situ. She was surgically treated and, after three months, remained healthy. Relevant risk factors, clinical and onychoscopic findings, diagnostic criteria, and treatment options are also discussed. Since many benign entities present similarly, high clinical suspicion is critical for diagnosing this entity.

Background: A previous study in Denmark suggested an increased melanoma risk associated with the use of flecainide. Objective: To study the association between flecainide use and the risk of melanoma and non-melanoma skin cancer in Spain and Denmark. Methods: We conducted a multi-database case-control study in (database/study period) Spain (SIDIAP/2005-2017 and BIFAP/2007-2017) and Denmark (Danish registries/2001-2018). We included incident cases of melanoma or non-melanoma skin cancer (NMSC) aged ≥18 with ≥2 years of previous data (≥10 years for Denmark) before the skin cancer and matched them to controls (10:1 by age and sex). We excluded persons with immunosuppression or previous cancer. We defined ever-use as any prescription fill and high-use as a cumulative dose of at least 200 g (reference: never-use). We categorized a cumulative dose for a dose-response assessment. We used conditional logistic regression to compute ORs (95% CI) adjusted for photosensitizing, anti-neoplastic, disease-specific drugs and comorbidities. Results: The total numbers of melanoma/NMSC cases included were 7,809/64,230 in SIDIAP, 4,661/31,063 in BIFAP, and 27,978/152,821 in Denmark. In Denmark, high-use of flecainide was associated with increased adjusted ORs of skin cancer compared with never-use [melanoma: OR 1.97 (1.38-2.81); NMSC: OR 1.34 (1.15-1.56)]. In Spain, an association between high-use of flecainide and NMSC was also observed [BIFAP: OR 1.42 (1.04-1.93); SIDIAP: OR 1.19 (0.95-1.48)]. There was a non-significant dose-response pattern for melanoma in Denmark and no apparent dose-response pattern for NMSC in any of the three databases. We found similar results for ever-use of flecainide. Conclusion: Flecainide use was associated with an increased risk of melanoma (Denmark only) and NMSC (Denmark and Spain) but without substantial evidence of dose-response patterns. Further studies are needed to assess for possible unmeasured confounders.

Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma that develops from dermal fibroblasts and spreads within the dermis and subcutaneous fat. It is locally aggressive, with a high local recurrence rate after excision but has extremely low metastatic potential. In the case of recurrent tumors, surgical excision with adequate margins is the gold standard treatment and may require adjuvant radiotherapy or chemotherapy in some cases. We conducted a retrospective analysis of individuals with dermatofibrosarcoma protuberance of the head and neck region that had treatment at our facility between 2016 and 2021. We gathered the data on the surgical techniques, reconstructive techniques used, histopathological features, adjuvant therapy, and outcomes. We treated three patients with head and neck dermatofibrosarcoma protuberance: one scalp lesion and two on the cheek. All three patients had recurrent tumors, two of whom were treated elsewhere for the primary lesion. One patient underwent surgery for a benign spindle cell tumor of the right cheek, but a final histopathological examination revealed dermatofibrosarcoma protuberance, and the tumor recurred within 3 months. The duration of recurrence is between 3 and 24 months. The size of the tumor ranges from 7.2 to 10.5 cm. The wide local excision margins range from 2 to 4 cm. Reconstruction ranges from split skin graft to regional flap. Inadequate margins raise the possibility of local recurrence in dermatofibrosarcoma protuberance.

Fibrofolliculoma is a benign tumor characterized by a smooth, dome-shaped papule of size 2-4 mm. Most fibrofolliculomas occur as multiple lesions, and very rarely, they are solitary. Herein, we report a case of solitary fibrofolliculoma found in the alar rim, without the typical characteristics of a fibrofolliculoma. A 42-year-old man visited the hospital with a protruding lesion that had occurred 1 year previously. A mass of size 5× 7 mm was observed on the left alar rim. The tumor was dome-shaped and palpable. The patient did not have any similar lesions elsewhere. No family member was known to have such a lesion. An incisional biopsy was performed before surgery, and pathological examination revealed hyperkeratosis and dyskeratosis; however, an accurate diagnosis was not made. Complete resection was planned for the mass on the alar rim. The resected mass was subjected to permanent biopsy, and the pathological examination results led to the diagnosis of fibrofolliculoma. Therefore, when diagnosing a dome-shaped mass in the alar rim, despite the suspicion of a very rare disease, it is necessary to suspect fibrofolliculoma and consider the process from diagnostic examination to treatment.