Pediatric dermatoses presenting as follicular papules are common entities encountered in clinical practice. These are a heterogeneous group of disorders of infectious or noninfectious origin that commonly present as regularly spaced, small papules with or without perifollicular inflammation. Inflammatory causes include follicular eczema, pityriasis rubra pilaris, lichen nitidus, follicular seborrheic dermatitis, keratosis pilaris and its variants, keratosis circumscripta, follicular psoriasis, lichen spinulosus, follicular lichen planus, follicular mucinosis, perforating folliculitis, follicular porokeratosis, and follicular dermographism. These conditions may arise due to filaggrin mutations, keratinization defects, autoimmunity, or microbial triggers. Nutritional causes include phrynoderma and scurvy, while connective tissue diseases such as dermatomyositis and chronic cutaneous lupus erythematosus are autoimmune. Additional categories include infectious, genetic, hormonal, environmental, frictional, malignant, nevus-related, iatrogenic, and idiopathic entities. An early and accurate diagnosis is essential for proper management and reducing disease-associated apprehension in children and/or their parents. This review attempts to describe the role of history taking and clinical examination, including morphology, location, pattern of distribution, and associated features, while dealing with a child with follicular-based papules. In addition, it delineates the role of dermoscopy and pathological examination in reaching a correct diagnosis. Furthermore, it describes the available treatment options and disease course of various follicle-based dermatoses.

Skin cutaneous melanoma (SKCM) is highly aggressive, has a poor prognosis, and readily develops drug resistance. Therefore, elucidating new mechanisms underlying the development and progression of cutaneous malignant melanoma, identifying specific new targets, and developing effective therapeutics based on these targets has become a current research priority. This study analyzed clinical tissue samples from SKCM patients, revealing that BLM DNA helicase (BLM) is highly expressed in SKCM tissues but minimally expressed in pigmented nevus tissues. Furthermore, BLM expression correlates with patient survival, highlighting its significant role in melanoma development. These findings position BLM as a promising target for anti-melanoma therapy. Building on this, a trifluoromethylpyrimidine derivative (FMD-108) targeting BLM was identified from a chemical library of natural products and derivatives developed by our team. In vitro and in vivo experiments demonstrated that FMD-108 notably inhibited cancer cell growth and metastasis, while significantly modulating the expression of DNA damage markers (γ-H2AX, p-CHK1, p-CHK2), apoptosis-related proteins (Bcl-2, Bax), and epithelial-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin, Vimentin). These results suggest that FMD-108 effectively suppresses melanoma cell proliferation and metastasis by inducing apoptosis, arresting the cell cycle at the G1 phase, and inducing DNA damage. These findings suggest that BLM may serve as a potential target in cutaneous malignant melanoma, providing a prospective strategy for clinical anti-melanoma drug development.

Congenital melanocytic nevus (CMN) is a melanocytic lesion present at birth or in early infancy, and most cases follow a benign clinical course. While the risk of malignant melanoma (MM) is known to be increased in giant CMN, the risk in small- to medium-sized CMN is considered low, and routine prophylactic excision is generally not recommended. We report a case of MM arising in a medium-sized CMN in a 23-year-old woman. The lesion had remained stable for many years but showed rapid enlargement and bleeding over a two-month period. Histopathological examination revealed nodular proliferation of atypical melanocytic cells with marked nuclear pleomorphism, high mitotic activity, and vascular invasion. Immunohistochemical analysis demonstrated diffuse Preferentially expressed Antigen in MElanoma positivity, a high Ki-67 labeling index, and loss of p16 expression. Based on the integrated evaluation of morphological and immunohistochemical findings, a diagnosis of MM arising in CMN was made. The tumor was classified as Stage IIc (T4bN0M0) according to the American Joint Committee on Cancer Eighth edition. This case highlights that even in small- to medium-sized CMN, rapid clinical changes such as enlargement and bleeding may represent important warning signs of malignant transformation. Careful clinical monitoring and appropriate patient education are essential for the early detection of MM in such lesions.

Nevus lipomatosus cutaneous superficialis (NLCS) is a unique hamartoma, characterized by ectopic adipose tissue in the dermis, which mainly localizes in buttock and thigh. This study elucidates a case of NLCS with fibroblastic nodular hyperplasia and reviews related literature. Herein, a 15-year-old boy was presented with subcutaneous mass consisting of multiple papules on the surface below his left knee joint for 5 years. The histopathological findings revealed ectopic mature adipose tissue and several storiform-arranged masses containing short fusiform cells and mast cells within the dermis and immunohistochemical staining indicated that CD10 was positive in the above fusiform cells. The diagnosis of nevus lipomatosus cutaneous superficialis with fibroblastic nodular hyperplasia was made. This study aims to increase awareness of this rare disease and its concomitant diseases for early recognition and proper treatment strategy.

Epidermal nevus and woolly hair may rarely coexist as part of mosaic RASopathies caused by postzygotic HRAS mutations. We report a 1-year-old boy with ipsilateral epidermal nevus and localized woolly hair, accompanied by right frontal encephalomalacia and developmental delay. Genetic testing revealed a mosaic HRAS mutation (c.34G>A, p.Gly12Ser) in lesional skin. This case expands the spectrum of HRAS-related mosaic RASopathies and highlights the association between epidermal nevus, woolly hair and neurological involvement.

Distinguishing malignant melanoma (MM) from benign melanocytic nevi presents a diagnostic challenge that can result in suboptimal management. We sought to assess whether quantifying nuclear and nucleolar areas in histological samples provided utility in differentiation. Our study used deidentified hematoxylin and eosin (H&E)-stained teaching slides, 77 MM cases and 73 benign nevi cases (N = 150). Using ImageJ software, 20 nuclei and their corresponding nucleoli were measured per slide in square pixels and converted to square microns. Nuclei selection was contingent on visualization of the nuclear envelope and a singular nucleolus. Mann-Whitney U tests were applied to compare average nuclear and nucleolar areas between groups. Significant differences were observed in both nuclear and nucleolar areas. The mean nuclear area was significantly larger in MM compared with benign nevi (702.04 ± 236.55 μm2 vs. 481.18 ± 153.89 μm2; P < 0.001). Similarly, the mean nucleolar area was markedly larger in MM compared with benign nevi (90.88 ± 52.25 μm2 vs. 58.03 ± 25.35 μm2; P < 0.001).

Bean syndrome, also known as blue rubber bleb nevus syndrome, is a rare congenital disorder characterized by multiple venous malformations affecting the skin, soft tissues, and gastrointestinal tract. Its main complication is chronic gastrointestinal bleeding, which can lead to iron-deficiency anemia and a lower quality of life. We present the case of a pediatric patient diagnosed with Bean syndrome, in whom typical skin lesions and gastrointestinal involvement were identified. We describe the clinical course, the diagnostic tests performed, and the treatment regimen initiated with sirolimus. This case highlights the importance of recognizing this condition in children for early diagnosis and timely treatment, as well as the need for multidisciplinary follow-up. Sirolimus represents a promising therapeutic option for severe cases, although it requires close monitoring.