Sebaceous nevus of Jadassohn: review and clinical-surgical approach

Line-Field Optical Coherence Tomography: Usefulness in the Non-Invasive Differential Diagnosis of Congenital Alopecia of Infancy

INTRODUCTION

Soon after birth, the clinical differential diagnosis between sebaceous of Jadassohn (NSJ), congenital triangular alopecia (CTA) and aplasia cutis congenita (ACC) may be challenging. A certain overlap of standard dermoscopic features can occur, especially in atypical cases, depending on scalp skin morphology and maturation age. The recently developed line-field confocal optical coherence tomography (LC-OCT) can provide morphological skin details with cellular resolution trough a rapid non-invasive examination.

OBJECTIVES

To assess the LC-OCT features of 6 cases of congenital alopecia of different aetiologies, with both typical and atypical clinical appearance.

METHODS

A non-invasive imaging examination combining standard dermoscopy, high-resolution videodermoscopy (HRVD) and LC-OCT was realized in 7 babies presenting for congenital alopecia with overlapping features, aged between 5 months and 5 years.

RESULTS

Based on the specific LC-OCT features, and supported by HRVD features, a diagnosis of NSJ, congenital triangular alopecia (CTA) and AC) were made in 4, 2 and 1 case, respectively.

CONCLUSIONS

The combined LC-OCT plus HRVD non-invasive imaging bring the advantage to have a real time diagnosis, to set the proper management and allows to avoid a skin biopsy in the perinatal age/first years of life at delicate skin site.

Syringocystadenocarcinoma papilliferum: a systematic review of clinical characteristics, reappraisal of associations, diagnostic pitfalls and management challenges

Syringocystadenocarcinoma papilliferum (SCACP) is a rare and aggressive malignant adnexal tumor originating from apocrine or pluripotent appendageal glands, often associated with a preceding syringocystadenoma papilliferum (SCAP) or nevus sebaceus (NS). This systematic review rigorously examines SCACP through an analysis of 78 cases documented between 1980 and 2024. The study aims to provide a comprehensive review of the clinical manifestations, diagnosis, treatment modalities, and outcomes associated with SCACP, while also reappraising its associations, particularly with NS. SCACP predominantly affects older adults, with an average age of 66.3 years and a slight male predominance, commonly presenting as ulcerated nodules or plaques on the scalp. This review highlights the aggressive nature of SCACP, evidenced by significant rates of metastasis and recurrence. Treatment is primarily surgical, with Mohs micrographic surgery offering potential benefits in terms of margin control and cosmetic outcomes. The association of SCACP with NS is critically evaluated, suggesting a complex etiopathogenesis and underscoring the importance of recognizing this association for timely diagnosis and management. Our review also briefly discusses potential pitfalls faced by clinicians in the diagnosis of SCACP. Our findings emphasize the need for standardized treatment protocols and further research into targeted therapies to improve patient outcomes in SCACP.

Topical trametinib for epidermal and sebaceous nevi in a child with Schimmelpenning-Feuerstein-Mims syndrome

We present the case of a 20-month-old girl with Schimmelpenning-Feuerstein-Mims (SFM) syndrome with extensive head, neck, and torso skin involvement successfully managed with topical trametinib. Trametinib interferes downstream of KRAS and HRAS in the MAPK signaling pathway, of which KRAS was implicated in our child's pathogenic variant. Although other dermatologic conditions have shown benefit from oral trametinib, its topical use has not been well reported. Our patient showed benefit from the use of twice-daily topical trametinib, applied to the epidermal and sebaceous nevi over a 16-month period, leading to decreased pruritus and thinning of the plaques.

Mosaic RASopathies concept: different skin lesions, same systemic manifestations?

BACKGROUND

Cutaneous epidermal nevi are genotypically diverse mosaic disorders. Pathogenic hotspot variants in HRAS, KRAS, and less frequently, NRAS and BRAF may cause isolated keratinocytic epidermal nevi and sebaceous nevi or several different syndromes when associated with extracutaneous anomalies. Therefore, some authors suggest the concept of mosaic RASopathies to group these different disorders.

METHODS

In this paper, we describe three new cases of syndromic epidermal nevi caused by mosaic HRAS variants: one associating an extensive keratinocytic epidermal nevus with hypomastia, another with extensive mucosal involvement and a third combining a small sebaceous nevus with seizures and intellectual deficiency. Moreover, we performed extensive literature of all cases of syndromic epidermal nevi and related disorders with confirmed pathogenic postzygotic variants in HRAS, KRAS, NRAS or BRAF.

RESULTS

Most patients presented with bone, ophthalmological or neurological anomalies. Rhabdomyosarcoma, urothelial cell carcinoma and pubertas praecox are also repeatedly reported. KRAS pathogenic variants are involved in 50% of the cases, especially in sebaceous nevi, oculoectodermal syndrome and encephalocraniocutaneous lipomatosis. They are frequently associated with eye and brain anomalies. Pathogenic variants in HRAS are rather present in syndromic keratinocytic epidermal nevi and phacomatosis pigmentokeratotica.

CONCLUSION

This review delineates genotype/phenotype correlations of syndromic epidermal nevi with somatic RAS and BRAF pathogenic variants and may help improve their follow-up.

Basal cell carcinoma arising within nevus sebaceous on the right scalp in a 55-year-old male: A case report and review of literature

We report here a case of nevus sebaceous in a 55-year-old male, who presented with a 50-year history of an asymptomatic swelling in his right scalp. The solitary, yellowish, expansile plaque over the scalp gradually became lobulated and turned dark-pigmented with spontaneous bleeding, itching discomfort, and occasional ulceration after scratching. The male's clinical presentation and histopathological findings were compatible with basal cell carcinoma arising in nevus sebaceous. At present, 5-aminolevulinic acid photodynamic therapy (ALA-PDT) emerges as a novel treatment modality which has proved safe and effective. In this case, three sessions of photodynamic therapy in combination with surgical excision were performed, leaving mild pigmentation within 3 weeks. The patient showed good cosmetic outcome, minimal scarring on the right scalp without further complications, disease recurrence or metastasis after ALA-PDT within six months.

Uncommon Large and Bilateral Fibrous Cephalic Plaques in a Patient with TSC2-Related Tuberous Sclerosis Complex

Tuberous sclerosis complex (TSC) is a genetic disorder, frequently characterized by early dermatological manifestations. The recognition and adequate description of these dermatological manifestations are of utmost importance for early diagnosis, allowing for the implementation of therapeutic and preventive measures. Fibrous cephalic plaques (FCPs) are considered a major diagnostic criterion for TSC, as FCPs are the most specific skin lesions of TSC. The localization, consistency, color, and size of FCPs vary widely, which can cause diagnostic delay, especially in patients with atypical presentations. The present report describes a female TSC patient with a confirmed heterozygous pathogenic genotype, NG_005895.1 (TSC2_v001): c.2640-1G>T, who presented with uncommon large and bilateral FCPs causing bilateral ptosis and marked with hyperostosis of the diploe that generated an asymmetry of the brain parenchyma. Differential diagnoses considered initially in this patient due to the atypical FCPs are described.

Successful Treatment of Sebaceous Nevus With Copper Vapor Laser

Introduction: Sebaceous nevus (SN) is a benign skin hamartoma with a potent transformation in benign or malignant tumors in adolescents or adults. Due to the most common location in the esthetic zone, an SN makes patients seek a dermatologist for cosmetic concerns on the face or neck. The surgical excision of a large-sized SN in the esthetic zone may require reconstruction with a skin flap and be associated with recurrences and scar formation. Case Report: We describe the successful treatment of the large-sized neck SN with copper vapor laser (CVL) for the first time. A left-sided neck SN (linear size of 27 mm) in the 24-year-old Caucasian female completely resolved after eight CVL sessions. The settings were as follows: average power accounted for 0.8-1.0 W, with a ratio at green (511 nm) and yellow (578 nm) wavelengths of 3:2. The pulse duration was set as 20 nanoseconds, the repetition rate 16.6 kHz, the exposure time 200 ms, light spot diameter of 1 mm. The CVL treatment resulted in the complete disappearance of the SN without remote side effects such as hyperpigmentation, scarring or recurrences 24 months after the treatment. The patient was satisfied with the excellent cosmetic results. Conclusion: The CVL treatment of the SN provides the most relevant result due to the complete elimination of SN cells and the remodeling of the vascular bed supplying the involved areas.

Nevus Sebaceous of Jadassohn in Adults-Can Reflectance Confocal Microscopy Detect Malignant Transformation?

Nevus sebaceous of Jadassohn (NSJ) is a rare congenital lesion that affects the adnexal structures of the skin. It is typically located on the scalp and face of females and presents as a well-defined, slightly elevated, yellow lesion. It is also linked to a high risk of secondary tumors, which are more frequently benign than malignant. In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging technique that provides a horizontal image of the skin with a resolution similar to histology. We report a case of basal cell carcinoma (BCC) developed in an NSJ with its dermoscopic, confocal, and histopathological features. A 49-year-old female presented with a well-circumscribed, 1 cm-diameter verrucous, yellowish lesion surrounded by a poorly defined, slightly erythematous, translucent plaque, located on the scalp in the temporoparietal region, which had been present since birth, grew at puberty, and changed its appearance in the last three years. Dermoscopy of the central lesion revealed yellow globules grouped into clusters, with peripheral linear and arborescent thin vessels, surrounded by several translucent nodular lesions with fine, arborizing vessels. RCM examination showed large, monomorphic cells with a hyperreflective periphery and a hyperreflective center located on the central lesion, corresponding to sebocytes, surrounded by multiple dark silhouettes lined with hyperreflective bands of thickened collagen, corresponding to tumor islands. The histopathological findings confirmed the diagnosis of BCC developed on an NJS. RCM can be a useful technique for the non-invasive examination and monitoring of these lesions, taking into account their transformation risk and preventing unnecessary excisions that might have a detrimental aesthetic impact on patients.

A Linear Waxy Verrucous Plaque of the Scalp

Nevus sebaceous of Jadassohn (NSJ) is an inborn, cutaneous hamartoma that is presented as a round-oval, or linear, yellowish-orange hairless plaque with an excess of sebaceous glands, typically localized to the head or neck. NSJ disease progresses slowly in three general stages. Due to its embryological origin, it yields an already documented potential for a variety of epidermal and adnexal tumors. The incidence of secondary neoplasms within NSJ is 10-30%, and the risk of neoplastic transformation increases with age. The majority of neoplasms are benign. Regarding malignant tumors, NSJ is usually associated with basal cell carcinoma. All neoplasms are typically encountered in long-standing lesions. Owing to NSJ's ample variety of associations with neoplasms, its management demands a case-driven tailored treatment. We present the case of a 34-year-old female with NSJ.