Two cases of type 2 segmental manifestation in a family with cutaneous leiomyomatosis.
Two cases of type 2 segmental manifestation in a family with cutaneous leiomyomatosis.
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皮肤平滑肌瘤病家系2型节段性表现2例。
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
R. Happle
中科院分区：
文献类型：
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作者：
A. König;R. Happle
常染色体显性遗传性皮肤病有两种节段性表现。类型1反映了潜在突变的杂合性，皮损的严重程度类似于观察到的非镶嵌表型。类型2反映杂合性丢失，节段性受累的特征是在普通表型上叠加更明显的表现。我们在此描述一例罕见的家族性皮肤平滑肌瘤病二型节段性表现。先证者为37岁女性，有多发性子宫肌瘤病史，右胸8×20厘米三角形区域内有多个凝集成团的坚硬的淡红色丘疹。在她的身体上发现了一些类似的孤立病变。她70岁的母亲同样报告了多发性子宫肌瘤的病史，并显示从她的左胸到左前臂伸肌表面的带状区域有肌瘤堆积。在她身体的其他部位也发现了一些孤立的非节段性病变。1955年，手术切除了1个病变，组织病理学检查显示为肌瘤特征。此外，家族病史显示先证者的祖母和一位阿姨患有皮肤肌瘤病。最有可能的是，这种在两代人中发生的节段性2型皮肤平滑肌瘤病的家族性表现是由于早期发育阶段的合子后杂合性丧失所致。我们假设潜在的基因位点特别容易发生有丝分裂重组或其他合子后突变事件，导致相应的野生型等位基因丢失。
Two types of segmental manifestation have been differentiated in autosomal dominant skin disorders. Type 1 reflects heterozygosity for the underlying mutation and the severity of lesions is similar to that observed in the nonmosaic phenotype. Type 2 reflects loss of heterozygosity and the segmental involvement is characterized by a more pronounced manifestation superimposed on the ordinary phenotype. We here describe an unusual familial occurrence of type 2 segmental manifestation of cutaneous leiomyomatosis. The proposita, a 37-year-old woman with a history of multiple uterine leiomyoma, showed multiple agminated firm, pale-red papules arranged in an 8 x 20 cm triangular area on her right chest. A few similar isolated lesions were found to be scattered all over her body. Her 70-year-old mother reported likewise a history of multiple uterine myoma and showed an accumulation of leiomyomas in a band-like area extending from her left chest to the extensor surface of her left forearm. Some isolated nonsegmental lesions were found in other areas of her body. In 1955, one lesion had been surgically removed and histopathological examination showed features of leiomyoma. Moreover, the family history revealed cutaneous leimyomatosis in the proposita's grandmother and in one aunt. Most likely, this familial occurrence of a segmental type 2 manifestation of cutaneous leiomyomatosis in two generations resulted from postzygotic loss of heterozygosity at an early developmental stage. We hypothesize that the underlying gene locus is particularly prone to mitotic recombination or other postzygotic mutational events resulting in loss of the corresponding wild-type allele.