We describe a 65-year-old man who presented with 'aches and pains' localized to the lower extremities, and was diagnosed with acute myeloid leukemia (AML). We hypothesize that this case represents an atypical presentation of AML with an immune-mediated necrotizing-like myopathy as a possible paraneoplastic manifestation of the disease, which improved after initiating chemotherapy. Our patient received a full course of 7 + 3 chemotherapy with cytarabine and daunorubicin. Proximal leg weakness and pain improved markedly following this treatment, establishing a temporal relationship between the possible paraneoplastic manifestation and treatment of underlying disease. Associations between malignancy and myopathies such as polymyositis and dermatomyositis have been well established in the literature. However, paraneoplastic IMNM is still a rare clinical phenomenon and has infrequently been associated with AML. This case may suggest myopathy and associated muscle 'aches and pains' as possible presenting symptoms of underlying AML, highlighting the heterogeneity of the clinical manifestations of this disease.

中文翻译：

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肌肉酸痛：我有白血病吗？

我们描述了一名 65 岁的男性，他出现了局限于下肢的“疼痛”，并被诊断出患有急性髓性白血病 (AML)。我们假设该病例代表 AML 的非典型表现，免疫介导的坏死样肌病可能是该疾病的副肿瘤表现，在开始化疗后有所改善。我们的患者接受了阿糖胞苷和柔红霉素的 7 + 3 化疗完整疗程。这种治疗后腿部近端无力和疼痛明显改善，在可能的副肿瘤表现和潜在疾病治疗之间建立了时间关系。恶性肿瘤与肌病（如多发性肌炎和皮肌炎）之间的关联已在文献中得到充分证实。然而，副肿瘤性 IMNM 仍然是一种罕见的临床现象，并且很少与 AML 相关。该病例可能表明肌病和相关的肌肉“疼痛”可能是潜在 AML 的症状，突出了这种疾病临床表现的异质性。