Adult T cell leukemia/lymphoma (ATLL) is a mature T cell neoplasm caused by the human oncogenic retrovirus human T lymphotropic virus type-1 (HTLV-1). While several musculoskeletal manifestations have been described in ATLL, skeletal muscle involvement is unusual, with only four cases reported in the English-language literature. We present a rare case of ATLL manifesting as an intra-muscular calf mass in a 58-year-old man who immigrated to the USA from West Africa. While skeletal muscle involvement by lymphoma is uncommon, it remains important to consider within the differential diagnosis when there are suggestive imaging findings because it entails important technical biopsy considerations as well as treatment implications. This case report also raises awareness of ATLL presenting outside of typical HTLV-1 endemic areas, related to current population migration patterns. ATLL should therefore be considered in patients with appropriate risk factors.

中文翻译：

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人小细胞T细胞淋巴瘤病毒1型相关淋巴瘤。

成人T细胞白血病/淋巴瘤（ATLL）是由人致癌逆转录病毒1型人类T淋巴病毒（HTLV-1）引起的成熟T细胞肿瘤。尽管在ATLL中描述了几种肌肉骨骼表现，但骨骼肌受累并不常见，英语文献中仅报道了4例。我们介绍了一个罕见的ATLL病例，该病例表现为一名58岁男子的肌肉内小腿肿块，该男子从西非移民到美国。虽然淋巴瘤累及骨骼肌并不常见，但在影像学表现提示时，在鉴别诊断中考虑仍然很重要，因为它涉及重要的技术活检和治疗意义。此案例报告还提高了在典型的HTLV-1流行地区之外出现ATLL的意识，与当前的人口迁移模式有关。因此，在具有适当危险因素的患者中应考虑使用ATLL。