Extranasal natural killer/T-cell lymphoma arising in the heart is rare and typically presents with non-specific clinical symptoms, necessitating a biopsy for a definitive diagnosis. We report an unusual case of a 48-year-old male who initially presented with chest pain and shortness of breath. Subsequent diagnosis via pericardial fluid analysis, including flow cytometry and immunohistochemical stains, revealed extranasal NK/T-cell lymphoma without sinonasal involvement. The analysis identified neoplastic lymphoid cells expressing CD2, cytoplasmic CD3, Epstein-Barr virus, and CD56 and exhibiting increased Ki-67 staining. Additionally, the patient developed hemophagocytosis lymphocytosis secondary to NK/T cell lymphoma. Treatment included an interleukin-1 receptor antagonist (anakinra), dexamethasone, rituximab, and etoposide. Unfortunately, the patient’s condition rapidly deteriorated, leading to multiorgan failure and eventual demise. Given the rarity of this lymphoma, early diagnosis based on a high suspicion level provides the best chance for improved overall survival.

发生在心脏的鼻外自然杀伤/T 细胞淋巴瘤很少见，通常表现为非特异性临床症状，需要进行活检才能明确诊断。我们报告了一名 48 岁男性的不寻常病例，他最初表现为胸痛和呼吸短促。随后通过心包液分析（包括流式细胞术和免疫组织化学染色）进行诊断，发现鼻外 NK/T 细胞淋巴瘤，无鼻窦受累。分析发现肿瘤性淋巴细胞表达 CD2、细胞质 CD3、Epstein-Barr 病毒和 CD56，并表现出 Ki-67 染色增强。此外，患者还出现继发于 NK/T 细胞淋巴瘤的噬血细胞和淋巴细胞增多症。治疗包括白介素 1 受体拮抗剂（阿那白滞素）、地塞米松、利妥昔单抗和依托泊苷。不幸的是，患者的病情迅速恶化，导致多器官衰竭并最终死亡。鉴于这种淋巴瘤的罕见性，基于高度怀疑水平的早期诊断为改善总体生存提供了最佳机会。