Central centrifugal cicatricial alopecia (CCCA) nomenclature describes a typical clinical presentation of cicatricial hair loss that begins on the vertex scalp with progressive, symmetric, and centrifugal evolution. However, atypical presentations have been noted clinically by the authors and reported in the literature. We sought to characterize the distribution of hair loss in published cases of adult patients with CCCA. A 3-step search process was used to evaluate research articles in Cumulative Index to Nursing & Allied Health, EMBASE, Google Scholar, MEDLINE, Scopus, and Web of Science databases. Studies with scalp photography or description of hair loss distribution were included. Three researchers evaluated eligible studies for clinical subtypes. Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Review was used to report results. Ninety-nine studies consisting of 281 cases of CCCA were included. Hair loss distributions included variants of the classic presentation along with distinct subtypes such as patchy, occipital, parietal, frontal, temporal, and trichorrhexis. Studies had significant homogeneity, as the classic distribution of CCCA was commonly reported. Additionally, clinically diagnosed cases may have concurrent diagnoses, and numerous studies did not report trichoscopy findings. CCCA terminology may not always be reflective of clinical presentation. Understanding atypical presentations is essential to inform appropriate and targeted treatment.

中文翻译：

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范围审查的经验教训：中央离心性疤痕性脱发的临床表现

中央离心性疤痕性脱发 (CCCA) 命名法描述了疤痕性脱发的典型临床表现，始于头顶头皮，呈进行性、对称性和离心性演变。然而，作者在临床上注意到并在文献中报道了非典型表现。我们试图描述已发表的 CCCA 成年患者病例中脱发的分布特征。使用三步搜索过程来评估护理与联合健康累积索引、EMBASE、Google Scholar、MEDLINE、Scopus 和 Web of Science 数据库中的研究文章。包括头皮摄影或脱发分布描述的研究。三名研究人员评估了临床亚型的合格研究。使用系统评价的首选报告项目和范围界定审查的荟萃分析扩展来报告结果。纳入了 99 项研究，共 281 例 CCCA 病例。脱发分布包括经典表现的变体以及不同的亚型，例如斑片状脱发、枕叶脱发、顶叶脱发、额叶脱发、颞叶脱发和脱发。研究具有显着的同质性，因为 CCCA 的经典分布被广泛报道。此外，临床诊断病例可能有并发诊断，并且许多研究没有报告毛发镜检查结果。 CCCA 术语可能并不总是反映临床表现。了解非典型表现对于指导适当和有针对性的治疗至关重要。