Vascular Stains and Hair Collar Sign Associated with Congenital Anomalies of the Scalp

Abstract

We reported a series of three meningothelial hamartomas, one benign fibrous tumor, and one aplasia cutis congenita presenting with the hair collar sign and a coexistent vascular stain. Our series highlighted the importance of coexisting cutaneous markers found in the newborn period. The presence of a vascular stain and hair collar sign with or without a congenital scalp nodule should increase suspicion of an associated cranial dysraphism.

Two cases of aplasia cutis congenita with hair collar signs and macrophage hyperplasia

“…A review of previously reported patients with hair collar signs revealed a significant risk of associated skull defects, direct connections to the central nervous system, and brain and cerebrovascular anomalies with this sign . In ACC cases, the presences of a hair collar sign and vascular stains are considered to be strong clinical indicators of skull or cerebrovascular involvement . Although we performed both imaging and histopathological examinations, no such disorders were found in our patients.…”

The hair collar sign

“…The literature contains 43 patients with the hair collar sign [Novy, 1938;Farmer and Maxmen, 1960;Commens et al, 1989;Singman et al, 1990;Sinclair et al, 1992;Toriello et al, 1993;Evers et al, 1994;Khallouf et al, 1994;Drolet et al, 1995a,b;Lees et al, 2000;Federici et al, 2004;Tiang et al, 2004;Fujita et al, 2005;Herron et al, 2005;Rogers et al, 2005;Neilan et al, 2006]. Including the 2 patients in this report, there are 22 males, 22 females, and 1 in which the sex was not specified.…”

Neurogenic Tumors of Soft Tissue

“…Extracranial meningothelial and neuroglial proliferations usually present as asymptomatic or slowly growing cutaneous or superficial subcutaneous nodules in children [55][56][57][58][59][60][61]. One tissue type generally predominates, but rare examples display a combination of mesenchymal and neuroectodermal elements [58,[62][63][64][65][66][67][68][69].…”

“…Clinically, the diagnosis may be suggested by the presence of circumscribed alopecia or congenital localized hypertrichosis, particularly when associated with a vascular stain (Fig. 3) [55,58,60,77,87,88]. The so-called ''hair collar'' sign is a not specific for meningothelial lesions, because it is also seen in other conditions associated with cranial dysraphia, such as encephalocele, glial heterotopia, and membranous aplasia cutis [89,90].…”

“…The histopathologic abnormality can sometimes be subtle, appearing as an alteration in the density of the cutaneous adnexa (usually decreased) or increased vascularity [57]. Higher power examination discloses scattered meningothelial cells in linear strands or small clusters within dense, hypocellular collagenous or fibromyxoid stroma infiltrating among adnexal structures or subcutaneous fibroadipose tissue [57,60,71,[76][77][78]. Cytologically, the cells are uniform and can be epithelioid or spindled, with bland oval or rounded nuclei, occasional intranuclear pseudoinclusions, and pale, homogeneous cytoplasm with indistinct cytoplasmic borders.…”