Massachusetts General Hospital, Boston, MA, USA.
Soma Jobbagy and Simmi Patel contributed equally to this manuscript.
Int J Surg Pathol. 2021 Oct;29(7):764-769. doi: 10.1177/10668969211002264. Epub 2021 Mar 22.
Hamartomas are primary, benign neoplastic lesions that most commonly derive from a single variably differentiated cell lineage. Here, we report an unusual case of a cardiac hamartoma. A 62-year-old woman presented with chest pain and palpitations. Serial imaging revealed a large slowly growing and highly vascularized left ventricular mass, which required surgical resection. Microscopically, the lesion was composed of nodular fibrovascular proliferation with haphazardly embedded muscle bundles and peripheral calcifications. Immunohistochemical studies revealed prominent muscle-specific actin positive and smooth muscle actin positive muscle fiber bundles within a disorganized fibrovascular stroma. This characterization is most consistent with cardiac mesenchymal hamartoma. Relevant differential diagnoses for this lesion include hamartoma of mature cardiac myocytes (HMCMs) and intramuscular hemangioma. The prominent smooth muscle differentiation of muscle bundles was incompatible with defining features of HMCM. Absence of S100-positive nerve and mature adipose cells distinguished this lesion from the recently defined, heterogeneous cardiac mesenchymal hamartoma. Forty-seven cases of cardiac hamartoma reported from 1970 to 2020 were reviewed to provide histopathologic context.
错构瘤是一种主要的良性肿瘤性病变，最常来源于单一的、具有不同分化潜能的细胞谱系。在这里，我们报告了一例心脏错构瘤的罕见病例。一名 62 岁女性因胸痛和心悸就诊。连续影像学检查显示左心室有一个大的、缓慢生长的、高度血管化的肿块，需要手术切除。显微镜下，病变由结节状纤维血管增生组成，伴有杂乱嵌入的肌束和外周钙化。免疫组织化学研究显示，在紊乱的纤维血管基质中存在突出的肌节肌动蛋白阳性和平滑肌肌动蛋白阳性的肌纤维束。这种特征最符合心脏间叶性错构瘤。该病变的相关鉴别诊断包括成熟心肌细胞错构瘤（HMCM）和肌内血管瘤。肌束中突出的平滑肌分化与 HMCM 的特征不一致。缺乏 S100 阳性神经和成熟脂肪细胞将该病变与最近定义的、异质性的心脏间叶性错构瘤区分开来。回顾了 1970 年至 2020 年报道的 47 例心脏错构瘤病例，以提供组织病理学背景。
