Clinical characteristics of intradermal nevus in the external auditory canal.

Melanocytic nevus occurring in the external auditory canal (EAC) is uncommon. Therefore, in the absence of sufficient clinical experience, this disease may be challenging to be suspected even with a physical examination. Herein, clinical and demographic features of intradermal nevus in the EAC were investigated. Patients with an intradermal nevus on histopathological examination (n = 15; 2 men and 13 women; P = .005) were included from a pool of patients who underwent surgical resection for EAC tumors between November 2011 and March 2022. Data were retrospectively collected on their sex, appearance of the lesions, surgical method, and outcomes. Nine patients had a dome shape and 6 patients had a papillomatous shape. Ten patients had dark colors and 5 patients had pale colors. All pale colors appeared only in the dome-shaped nevus, and only dark colored papillomatous nevi were observed. A significant difference was noted in terms of the frequency of occurrence by colors (dark or pale) according to shape (dome or papillomatous) (P = .044). No patient showed recurrence or EAC stenosis after circumferential excision. In women, a dome-shaped or papillomatous mass with dark color in the EAC may likely be predicted as the nevus. However, it can also occur in men, and even if it is a pale color, in the case of a dome shape, taking the nevus into account is important. Moreover, successful treatment outcomes were achieved through circumferential excision.

Dermoscopic patterns of intradermal naevi.

BACKGROUND: Intradermal naevi represent a benign histopathological variant of common melanocytic naevi. Studies describing dermoscopic criteria of dermal naevi are very limited. OBJECTIVES: To identify dermoscopic features of dermal naevi in order to facilitate differential diagnosis from malignant lesions. METHODS: A 15-year retrospective study was performed to evaluate the dermoscopic characteristics of 202 dermal naevi, histopathologically diagnosed through the analysis of digital dermoscopic images performed with polarised light dermoscopy. For each lesion, vascular pattern, pigment pattern and other dermoscopic clues were evaluated. RESULTS: 147 Unna naevi and 55 Miescher naevi were included in the study. Brown pigment (37.1%) was the pigment pattern most frequently observed in both Unna and Miescher naevi, followed by cobblestone pattern (30.6%) in Unna naevi and white areas (23.6%) and dotted/globule pattern (20%) in Miescher naevi. As regards the vascular patterns, the polymorphic one was the most frequently observed (34.6%). The combination between comma-shaped and arborising vessels was the most common among all naevi. CONCLUSIONS: Our study describes the dermoscopic features of dermal naevi that may help to differentiate them from malignant lesions such as basal cell carcinoma, amelanotic melanoma and Spitz naevi.

Osteonevus of Nanta: a case report in a combined melanocytic nevus

Abstract Secondary osteoma cutis is a phenomenon that may occur in several conditions. When it occurs in a melanocytic nevus it is named osteonevus of Nanta, an event considered uncommon and characterized by the presence of bone formation adjacent or interposed with melanocytic cells. There are reports of its occurrence in various melanocytic lesions, being more frequently associated with intradermal nevus. We report a case of osteonevus of Nanta in combined nevus, possibly the first description of this association.

Adult-onset porokeratotic eccrine ostial and dermal duct nevus:dermatoscopic findings and treatment with tazarotene.

Porokeratotic eccrine ostial and dermal duct nevus (PEODDN) is a rare dermatosis initially described as 'comedo nevus' and renamed 'PEODDN'; it has also been referred to as linear eccrine nevus with comedones, porokeratotic eccrine ostial and hair follicle nevus, and porokeratotic adnexal ostial nevus. PEODDN is usually present at birth or develops early in life. Rarely, PEODDN can develop in adults. The treatment of this puzzling condition is not standardized. We report herein a new case of adultonset PEODDN with dermatoscopic images. Our patient responded favorably to topical tazarotene.

Osteonevus of Nanta: a case report in a combined melanocytic nevus.

Secondary osteoma cutis is a phenomenon that may occur in several conditions. When it occurs in a melanocytic nevus it is named osteonevus of Nanta, an event considered uncommon and characterized by the presence of bone formation adjacent or interposed with melanocytic cells. There are reports of its occurrence in various melanocytic lesions, being more frequently associated with intradermal nevus. We report a case of osteonevus of Nanta in combined nevus, possibly the first description of this association.

Nodular skin lesions: correlation of reflectance confocal microscopy and optical coherence tomography features.

BACKGROUND: Nodular lesions have common clinical appearance but different prognoses. Differential diagnosis between melanoma (MM), basal cell carcinoma (BCC) and dermal naevus (DN) poses a challenge in clinical practice. Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) are promising non-invasive imaging techniques, potentially able to decrease redundant biopsies. RCM allows in vivo visualization of skin down to the papillary dermis at almost histological resolution, while OCT, particularly dynamic OCT (D-OCT), provides images deeper within the dermis and reveals the vascular pattern. OBJECTIVES: To identify correlating features observed with RCM and OCT associated with the different nodular lesion diagnoses. METHODS: We retrospectively assessed 68 nodular lesions (30 MM, 20 BCC and 18 DN) with RCM and subsequently OCT. At the end of the study, evaluations were matched with histopathological diagnosis and statistical analysis was performed. RESULTS: In MM, 57% (17/30) evidenced both cerebriform nests at RCM and icicle-shaped structures at OCT, with higher average Breslow index. In 80% of BCCs with basaloid islands at RCM, OCT showed ovoid structures. More than half of DN (56%) showed hyporeflective nests at OCT and either dense nests or dense and sparse nests at RCM. CONCLUSIONS: The combined use of RCM and OCT offers a better understanding of the morphological architecture of nodular lesions, correlating RCM parameters with OCT and vice versa, assisting in turn with early differential diagnosis of malignant and benign nodular lesions. The correlation between icicle-shaped structures and cerebriform nests in MM and their association with Breslow index requires future research.

Juvenile melanocytic acral nevus: A comparative study between MANIAC and non-MANIAC nevus and its clinicopathological characteristics.

BACKGROUND: Melanocytic acral nevi have a series of distinguishing features, including their location, patient age at onset, clinical progression, and histological findings. In particular, histopathological analysis often reveals a melanocytic acral nevus with intraepidermal ascent of cells (MANIAC nevus), which in some cases can be mistaken for atypia or malignancy. AIM: This study describes the clinicopathological characteristics of acral nevi in patients under 18 years old and contrasts the clinical and histological features between MANIAC vs non-MANIAC nevi. METHODS: This was a retrospective observational study, performed in our department in the decade between January 2007 and January 2017. We included patients younger than 18 years of age who were subjected to the removal of melanocytic acral nevi. RESULTS: A total of 70 patients were studied. 54.2% (38/70) were females and 45.8% (32/70) were males. With regard to the type of nevus, 34 were compound, 27 were junctional, and 9 were predominantly intradermal lesions. We identified a total of 41 MANIAC nevi and 29 non-MANIAC nevi. Statistically significant differences between these two groups were identified in nevus size (larger in MANIAC) and the frequency of compound nevi (higher in the MANIAC group), but not in the remainder of the histological parameters studied.

An Atypical Fibroxanthoma and Intradermal Nevus Collision Tumor-Potential for Misdiagnosis.

Atypical fibroxanthomas (AFX) are rare cutaneous tumors, which typically present as a solitary ulcerated papule or nodule on sun-damaged skin. Despite malignant-appearing features on histology, AFX typically pursue a benign clinical course. In rare instances, AFX can form collision tumors with other lesions. However, to the best of our knowledge, AFX in collision with a nevus has never been previously reported. In this study, we describe such a lesion for its novelty and challenge in diagnosis, as this case was originally considered to be melanoma arising in a nevus. On histologic examination, there were 2 distinct populations of cells; one composed of markedly atypical and pleomorphic epithelioid and oval to spindled cells, consistent with AFX, and the other, a bland-appearing intradermal nevus with congenital features. The AFX population stained positive with smooth muscle actin, CD10, and CD68 and was negative for S100, SOX10, Melan-A, desmin, pancytokeratin, CK5/6, and p63. Deep to this was a second population of small, bland-appearing melanocytes in a broad, band-like distribution. This unusual collision tumor between AFX and an intradermal nevus highlights the important role immunohistochemistry plays in avoiding the misdiagnosis and potential overtreatment of benign or low-grade lesions, and in identifying potential mimickers.

Nevo poroqueratósico del ostium y el ducto dérmico ecrinos: reporte de caso / Porokeratotic eccrine ostial and dermal duct nevus: case report

El Nevo Poroqueratósico del Ostium y el Ducto Dérmico Ecrinos (NPODDE), es un raro hamartoma benigno de los conductos de las glándulas sudoríparas ecrinas, puede presentarse desde el nacimiento o también en edades posteriores. Su etiología plantea una alteración en la queratinización debido a una mutación somática en el gen GJB2 que codifica para una proteína de unión gap. Esta mutación también está relacionada con el síndrome KID por lo cual la asesoría genética es crucial en estos pacientes. Clínicamente puede presentarse como hoyuelos hiperqueratósicos en palmas y plantas que normalmente son asintomáticos. El diagnostico se confirma con la histopato-logía que muestra una laminilla cornoide sobre el conducto ecrino subyacente. La entidad es benigna y de difícil tratamiento siendo refractaria a varias modalidades terapéuticas. Se presenta un caso de un paciente adulto masculino con lesiones típicas en palmas y plantas, a quien con la biopsia de piel se le confirmó el diagnóstico de NPODDE. Dado la baja frecuencia de esta condición el objetivo de este artículo radica en actualizar los aspectos más relevantes de esta entidad.

Porokeratotic Eccrine Ostial and Dermal Duct Nevus (PEODDN) is a rare benign hamartoma of eccrine sweat gland ducts, it can present from birth or also at later ages. Its etiology implies an alteration in keratinization due to a somatic mutation in GJB2 gene, that codes for a gap junction protein. This mutation is also associated with KID syndrome so genetic counseling for parents is crucial. Clinically it can present as keratotic pits in palms and soles that are usually asymp-tomatic. The diagnosis is confirmed by histopathology that shows a cornoid lamellae on the underlying eccrine duct. The entity is benign and the treatment is difficult, being refractory to seve-ral therapeutic modalities. We present a case of a male adult patient with typical lesions on palms and soles, who was diagnosed with PEODDN by skin biopsy. Given the low frequency of this con-dition, the objective of this article is to update the most relevant aspects of this entity.

Case for diagnosis. Ulcerated intradermal nevus simulating Sister Mary Joseph's nodule

Abstract: We report a case of a 76-year-old patient with a history of recent weight loss and ulcerated umbilical nodular lesion. Initially, we considered the diagnostic hypothesis of Sister Mary Joseph's nodule. However, histopathological evaluation revealed that it was an ulcerated intradermal nevus. We perform a brief review of umbilical nodules.

Case for diagnosis. Ulcerated intradermal nevus simulating Sister Mary Joseph's nodule.

We report a case of a 76-year-old patient with a history of recent weight loss and ulcerated umbilical nodular lesion. Initially, we considered the diagnostic hypothesis of Sister Mary Joseph's nodule. However, histopathological evaluation revealed that it was an ulcerated intradermal nevus. We perform a brief review of umbilical nodules.