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To the Editor: Molluscum contagiosum (MC) is caused by a double-stranded DNA virus of the Poxviridae family [1]. The typical clinical presentation consists of dome-shaped, shiny, waxy papules with central umbilication. Lesions are usually 2–5 mm in diameter. Giant molluscum contagiosum, however, typically presents as a solitary, firm nodule larger than 10 mm in diameter. This form can mimic a tumor and is therefore easily misdiagnosed. We successfully utilized dermoscopy and high-frequency ultrasound (HFUS) to diagnose a rare case of giant MC in a child. A 6-year-old male presented with a 6-month history of an asymptomatic, erythematous nodule on his right heel. Physical examination revealed a solitary, firm, well-defined, erythematous nodule measuring approximately 1.5 × 1.3 cm, with a surface of fine scales (Figure 1A). No similar lesions were found elsewhere on his body. He had no evidence of systemic disease, HIV infection, or immunodeficiency. Based on the clinical presentation and history, differential diagnoses included dermatofibroma, keratoacanthoma, eccrine poroma, pyogenic granuloma, verruca vulgaris, adnexal tumor, and cutaneous cryptococcosis. Although a pathological biopsy was initially recommended, the parents declined the procedure. Dermoscopic examination was therefore performed, which revealed white-yellowish amorphous structures surrounded by linear blood vessels (Figure 1B). Furthermore, an HFUS scan showed a hypoechoic, dome-shaped nodule confined to the epidermis (Figure 1C). Together, these noninvasive findings supported a diagnosis of giant molluscum contagiosum. To treat the lesion, curettage was performed, removing cheesy, brain-like material. Subsequent histopathologic analysis of this material revealed epidermal cytoplasmic vacuolization and eosinophilic inclusion bodies (Figure 1D), confirming the diagnosis. During an 8-month follow-up period, the parents reported no recurrence of the lesion. MC is a common, benign, chronic, and localized skin infection caused by the molluscipox virus. It can occur anywhere on the body, including the palms and soles [1]. MC lesions can present with variable distribution patterns, such as scattered, clustered, linear, or single. The infection is transmitted through direct skin-to-skin contact, autoinoculation, or indirectly via fomites such as towels, clothing, swimming pools, and shared baths [1, 2]. It is particularly common in children, with a reported prevalence of 5%–11% [3]. Diagnosis is typically confirmed through clinical history and characteristic features, including pink to skin-colored, dome-shaped, shiny, waxy papules with central umbilication, usually measuring less than 2–5 mm in diameter. In rare instances, a solitary giant MC lesion, as observed in this case, can mimic a cutaneous neoplasm. The differential diagnosis includes, but is not limited to, dermatofibroma, keratoacanthoma, eccrine poroma, pyogenic granuloma, verruca vulgaris, adnexal tumor, and cutaneous cryptococcosis. On dermoscopy, these differentials exhibit characteristic features. Dermatofibroma typically displays a peripheral delicate pigment network and a central white scar-like patch [4, 5]. Keratoacanthoma presents with concentric circles of a central crater, keratin mass, keratin scales, keratinizing pearls (or white circles), and a polymorphic vascular pattern [6, 7]. Eccrine poroma is characterized by a white-to-pink halo surrounding polymorphic vessels such as glomerular and hairpin types, along with pink-white structureless areas and red lacunae [8, 9]. Pyogenic granuloma exhibits a homogeneous area, a white collarette, or white rail lines [10]. Verruca vulgaris demonstrates packed papillae with bleeding spots, dotted vessels, and linear vessels [11, 12]. The dermoscopic manifestations of skin adnexal tumors are diverse, among which arborizing telangiectasias are common [13]. Cutaneous cryptococcosis displays a yellowish halo, a white structureless area, and an irregular vascular pattern [14]. The dermoscopic features observed in our case were significantly different from those of the aforementioned differential diagnoses and were more consistent with the known dermoscopic findings of MC. HFUS is currently utilized for the diagnosis, differential diagnosis, and management of skin tumors and inflammatory diseases due to its high resolution and good correlation with histopathology [15]. However, its practical clinical application remains limited compared to other noninvasive imaging techniques, resulting in insufficiently summarized characteristic sonographic findings for many diseases. This study presents the first description of HFUS manifestations in MC. In this case, HFUS revealed epidermal thickening, increased echogenicity, discontinuity, and a well-defined hypoechoic dome-like structure (Figure 1C). The thickening and echogenicity of the epidermis were associated with thickened granular and spinous layers filled with eosinophilic inclusion bodies and increased keratin. The ill-defined hypoechoic dome-like structure observed in this case corresponded to a cup-shaped pseudotumor formed on the epidermis (Figure 1D). As this study is based on a single case report, future studies with a larger sample size are necessary to comprehensively summarize the sonographic spectrum of MC and to correlate these findings with histopathological features. When managing pediatric patients, it is vital to consider their propensity to resist surgical interventions and to carefully evaluate the associated anesthesia-related risks. In situations where surgical intervention and histopathological examination are not suitable or are declined, dermatological imaging techniques can provide valuable diagnostic clues. These techniques facilitate informed clinical decisions and enable the selection of optimal treatment modalities. Diagnosing isolated giant MC presents a significant clinical challenge. In such cases, noninvasive diagnostic techniques such as dermoscopy and HFUS play a crucial role. They facilitate diagnosis and help rule out other conditions when a pathological biopsy is not feasible or is declined. Furthermore, these techniques enhance physician–patient communication, particularly in pediatric care. They are instrumental in guiding appropriate management strategies and preventing unnecessary interventions. Collected sample: Z.Z., J.H.F., L.Z., and J.W.L. Performed the experiments: Z.Z., J.H.F., L.Z., and J.W.L. Wrote and revised the paper: Z.Z., J.H.F., and J.W.L. All authors read and approved the final manuscript. This work was supported by Jiwei Li, attending doctor of the patient and main author; and also by the Technical Innovation Talent Training Target Project (grant number: 202305AD160058), the Kunming Medical Science and Technology Academic Leading Talent Project (grant number: 2024-SW-14), the Research Project of the Yunnan Provincial Clinical Medicine Center (grant number: 2024YNLCYXZX0478), the Research Project of the Yunnan Provincial Clinical Medicine Center (grant number: 2024YNLCYXZX0467), and the Bathune Charitable Foundation (grant number: 2022E17-B13). This study was approved by the Medical Ethics Committee of Kunming Children's Hospital. All methods were performed in accordance with the ethical standards as laid down in the Declaration of Helsinki and its later amendments or comparable ethical standards. Written informed consent was obtained from the patient's parents for publication of this case report and accompanying images, and the proof can be requested at any time. The authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.