Acquired and familial mucinous nevus

Abstract

An 8-year-old boy consulted about a 1-year asymptomatic plaque on the left dorsal side of the spine. The patient had had no previous antecedents to note and presented no injury or scratch marks in the region. Upon physical examination, we observed a 3.5 · 2.0 cm in size ovalshaped plaque that extended laterally outwards from the spine with a slight blaschkoid pattern. The surface presented a slightly raised appearance, flesh colored with lightly hyperpigmented edges ( Fig. 1a).A biopsy was performed which showed an epidermis with acanthosis and papillomatosis. The dermis and the hypodermis did not seem to be affected, however, a colloid iron stain showed diffuse blue deposits in the upper dermis between the collagen bundles. Accordingly, the patient was diagnosed with mucinous nevus. No treatment was started, and the lesion remained stable in the following months. Case 2A 14-year-old girl was seen in consultation for a two-year history of a brown lesion on her back. The lesion was largely asymptomatic, and there was no antecedent of trauma or scratching in this area. Cutaneous examination showed a solitary brownish, firm plaque, 3 cm in diameter located on the lumbosacral region ( Fig. 1b). There were no other skin or mucosal abnormalities.An incisional biopsy from the solitary plaque was performed, and the histopathologic pictures showed an acanthotic epidermis with thin, elongated rete ridges and minimal basket-weave hyperkeratosis (Fig. 2a).The striking feature was the massive deposit of mucinous material in the whole dermis that stained positive with alcian blue at pH 2.5 (Fig. 2b). With the van Gieson stain, the density of elastic fibers was shown to be slightly reduced. Masson trichrome staining failed to demonstrate collagen fiber alterations. There were no abnormalities in eccrine sweat glands.Results of laboratory studies were within normal limits. Case 3A 14-year-old girl, twin sister of the previous case, presented with a well-defined plaque in the same area similar to her sister that had appeared some months previously. 1283

A Case of Mucinous Nevus Clinically Mimicking Nevus Lipomatosus Superficialis

“…Mucinous nevus is a neoplastic hamartoma and a rare form of primary cutaneous mucinosis2. Mucinous nevus clinically presents as grouped brownish papules and confluent plaques, usually with a unilateral, linear, zosteriform, or grouped distribution.…”

“…Mucinous nevus clinically presents as grouped brownish papules and confluent plaques, usually with a unilateral, linear, zosteriform, or grouped distribution. It usually appears at birth or in early childhood and mainly occurs on the back2. Although most cases are sporadic, the possibility of familial association has been suggested2.…”

“…It usually appears at birth or in early childhood and mainly occurs on the back2. Although most cases are sporadic, the possibility of familial association has been suggested2. The nevoid feature of mucinous nevus needs to be clinically differentiated from epidermal nevus or NLS.…”

Mucinous Nevus

“…1 There have been only a few isolated reports of Poland syndrome with congenital dermatoses. [2][3][4] Adding to this association list, we report a case of Poland syndrome with multiple congenital melanocytic nevi (CMN). Additionally, the nevi are in a Blaschkolinear arrangement, which is also rare; we know of only 2 such cases reported previously.…”

“…Seventy-one percent of cases were reported in men, and the most common location was the back. [1][2][3][4] Of note, 45% of cases were reported in Asian countries. Half of all cases were present at birth, while the remainder developed in childhood, adolescence, or early adulthood.…”