Pediatric Skin Center, Department of Dermatology, University Children's Hospital Zurich, Zurich, Switzerland.
Unité de Dermatologie Pédiatrique, Services de Dermatologie et de Pédiatrie, Département Femme-mère-enfant, Site de l'Hôpital de L'enfance, Lausanne, Switzerland.
J Eur Acad Dermatol Venereol. 2021 Oct;35(10):2085-2090. doi: 10.1111/jdv.17319. Epub 2021 May 22.
Postzygotic mutations in FGFR2 have been identified in mosaic forms of acne, keratinocytic epidermal nevi, nevoid acanthosis nigricans / rounded and velvety epidermal nevus and in two fetuses with papillomatous pedunculated sebaceous nevus (PPSN).
To determine the clinical and genetic characteristics of children with cerebriform, papillomatous and pedunculated variants of sebaceous nevi.
Infants diagnosed with sebaceous nevi characterized by a cerebriform, papillomatous and/or pedunculated morphology over a 10-year period (2010-2019) at three paediatric dermatology centres in Switzerland and France were included in this case series. Clinical and histological characteristics were assessed. Next-generation sequencing was used to assess for FGFR2 mutations.
All nevi were located on the head, with a rounded or linear shape and a typical cerebriform, sometimes papillomatous and pedunculated, surface. No associated extracutaneous anomalies were found. Nevi harboured postzygotic mutations in the transmembrane domain of FGFR2 in 6/8 children (75%), either the known specific p.(Cys382Arg) mutation in 5 cases, or a novel mutation, p.(Val395Asp), in one.
We found an exquisite genotype-phenotype correlation in these rare nevi, with specific postzygotic mutations in the transmembrane domain of FGFR2. As not all lesions were truly papillomatous and pedunculated, the term cerebriform sebaceous nevus (CSN) appears more suitable than PPSN to describe this entity. The cerebriform pattern of CSN is reminiscent of cutis gyrata, as seen in Beare-Stevenson syndrome, which is caused by closely related germline FGFR2 mutations. While clinically impressive, CSN seem to carry a good prognosis and a low risk for extracutaneous associations.
FGFR2 的合子后突变已在粉刺的嵌合体形式、角朊细胞表皮痣、神经嵴黑棘皮病/圆形和天鹅绒状表皮痣以及两个具有乳头状带蒂的皮脂痣（PPSN）的胎儿中被鉴定出来。
确定具有脑回状、乳头状和带蒂变异的皮脂痣患儿的临床和遗传特征。
在瑞士和法国的三个儿科皮肤科中心，对在 10 年期间（2010-2019 年）诊断为具有脑回状、乳头状和/或带蒂形态的皮脂痣的婴儿进行了这项病例系列研究。评估了临床和组织学特征。使用下一代测序来评估 FGFR2 突变。
所有的痣都位于头部，呈圆形或线性，具有典型的脑回状，有时呈乳头状和带蒂状。未发现任何相关的皮肤外异常。在 6/8 名儿童（75%）的痣中发现 FGFR2 跨膜结构域的合子后突变，5 例为已知的特异性 p.(Cys382Arg)突变，1 例为新的突变 p.(Val395Asp)。
我们在这些罕见的痣中发现了一种精细的基因型-表型相关性，具有 FGFR2 跨膜结构域的特定合子后突变。由于并非所有病变都是真正的乳头状和带蒂状，因此术语脑回状皮脂痣（CSN）似乎比 PPSN 更适合描述这种实体。CSN 的脑回状模式让人联想到 Beare-Stevenson 综合征中所见的脑回状皮肤，这是由密切相关的种系 FGFR2 突变引起的。虽然 CSN 在临床上令人印象深刻，但似乎预后良好，且发生皮肤外关联的风险较低。
