Mastocytosis is a heterogeneous group of neoplasms defined by a numerical increase and accumulation of clonal mast cells (MCs) in various organ systems. The disease may present as cutaneous mastocytosis or systemic mastocytosis (SM). On the basis of histopathological and molecular features, clinical variables, and organ involvement, SM is divided into indolent SM, smoldering SM, SM with an associated hematologic neoplasm, aggressive SM, and MC leukemia. Each variant is defined by unique diagnostic criteria and a unique spectrum of clinical presentations. A key driver of MC expansion and disease evolution is the oncogenic machinery triggered by mutant forms of KIT. The genetic background, additional somatic mutations, and comorbidities also contribute to the course and prognosis. Patients with SM may also suffer from mediator-related symptoms or even an MC activation syndrome. This article provides an update of concepts on the genetics, etiology, and pathology of mastocytosis, with emphasis on diagnostic criteria and new treatment concepts.

中文翻译：

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肥大细胞增多症发病机制的新见解：诊断和治疗的新兴概念


肥大细胞增多症是一组异质性肿瘤，其定义是克隆肥大细胞 （MC） 在各种器官系统中的数量增加和积累。该疾病可能表现为皮肤肥大细胞增多症或系统性肥大细胞增多症 （SM）。根据组织病理学和分子学特征、临床变量和器官受累，SM 分为惰性 SM、阴燃性 SM、伴有相关血液系统肿瘤的 SM、侵袭性 SM 和 MC 白血病。每种变异都由独特的诊断标准和独特的临床表现谱定义。MC 扩增和疾病进化的关键驱动因素是由 KIT 突变形式触发的致癌机制。遗传背景、其他体细胞突变和合并症也影响病程和预后。SM 患者还可能患有介质相关症状，甚至 MC 激活综合征。本文提供了肥大细胞增多症的遗传学、病因学和病理学的最新概念，重点介绍了诊断标准和新的治疗理念。