Seth Neha, Abeykoon Jithma P, Goyal Gaurav, Go Ronald S, Tessier Steven, King Rebecca L, Ravindran Aishwarya
Department of Pathology and Laboratory Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, New York, NY 11548, USA.
Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
Cancers (Basel). 2025 Jun 19;17(12):2055. doi: 10.3390/cancers17122055.
Mesenchymal dendritic cell neoplasms represent a distinct category of hematologic malignancies that challenge traditional classifications of histiocytic and classical dendritic/Langerhans cell neoplasms. Historically grouped under the broader umbrella of dendritic cell neoplasms, these entities differ significantly in their ontogeny, histopathologic features, molecular alterations, and clinical behavior. They are categorized into three main subtypes including follicular dendritic cell sarcoma, fibroblastic reticular cell tumor, and EBV-positive inflammatory follicular dendritic cell sarcoma/fibroblastic reticular cell tumor. They originate from mesenchymal stromal cells, and genetic alterations activating the NF- κβ pathway are frequent in follicular dendritic cell sarcomas. Immunophenotypic characterization is critical to distinguish these from other hematologic malignancies including histiocytic and classical dendritic/Langerhans cell neoplasms and other solid (non-hematopoietic) cancers. This review recapitulates current knowledge on existing classifications, details their diverse ontogeny from classical dendritic cell neoplasms, and provides insights into their clinicopathologic characteristics to improve diagnostic accuracy. We detail two case studies that demonstrate the challenges involved in the histopathologic diagnosis of these rare tumors, necessitating a comprehensive workup. Integrating developmental biology into practical diagnostic algorithms is essential to improve recognition and classification of these underdiagnosed neoplasms, ultimately guiding timely management.
间充质树突状细胞瘤是血液系统恶性肿瘤中的一个独特类别，对组织细胞性肿瘤以及经典树突状细胞/朗格汉斯细胞肿瘤的传统分类提出了挑战。历史上，这些实体被归入更广泛的树突状细胞瘤范畴，它们在个体发生、组织病理学特征、分子改变和临床行为方面存在显著差异。它们分为三个主要亚型，包括滤泡树突状细胞肉瘤、成纤维网状细胞瘤和EB病毒阳性炎症性滤泡树突状细胞肉瘤/成纤维网状细胞瘤。它们起源于间充质基质细胞，激活NF-κβ通路的基因改变在滤泡树突状细胞肉瘤中很常见。免疫表型特征对于将这些肿瘤与其他血液系统恶性肿瘤（包括组织细胞性肿瘤以及经典树突状细胞/朗格汉斯细胞肿瘤）和其他实体（非造血）癌症区分开来至关重要。本综述总结了关于现有分类的当前知识，详细阐述了它们与经典树突状细胞瘤不同的个体发生过程，并深入探讨了它们的临床病理特征以提高诊断准确性。我们详细介绍了两个病例研究，展示了这些罕见肿瘤组织病理学诊断中所涉及的挑战，这需要全面的检查。将发育生物学整合到实际诊断算法中对于提高这些诊断不足的肿瘤的识别和分类至关重要，最终指导及时的治疗。
