炎性肌纤维母细胞瘤（IMT）是一种罕见的起源于间叶组织的肿瘤。上皮样炎性肌纤维母细胞肉瘤 (EIMS) 是一种罕见且特别具有侵袭性的变异，与较差的预后相关。几乎所有 EIMS 病例均表现出激活的间变性淋巴瘤激酶 (ALK) 基因重排，这表明 EIMS 患者可能会受益于 ALK 酪氨酸激酶抑制剂 (TKI) 的治疗。我们介绍了一名 34 岁女性的病例，她被诊断患有纵隔 EIMS，并具有罕见的棘皮动物微管相关蛋白样 4 (EML4) -ALK 融合。经过 15 个月的新辅助洛拉替尼治疗后，患者接受了完整的手术切除，获得了病理学完全缓解。鉴于与 EIMS 相关的术后复发风险较高，患者的治疗计划包括持续使用劳拉替尼进行辅助治疗。截至目前，患者的总体生存期已超过 2 年，且未观察到肿瘤复发。因此，该病例提供了宝贵的临床证据，支持新辅助劳拉替尼治疗 ALK 阳性局部纵隔 EIMS 患者的潜在益处，并具有可耐受的安全性。版权所有 © 2024 Cheng、Zhao、Ren、Xue、Yan 和 Huang。

Inflammatory myofibroblastic tumor (IMT) is a rare tumor originating from mesenchymal tissue. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) represents a rare and particularly aggressive variant, associated with a worse prognosis. Almost all EIMS cases exhibits activating anaplastic lymphoma kinase (ALK) gene rearrangements, which suggests that EIMS patients may potentially benefit from treatment with ALK tyrosine kinase inhibitors (TKIs). We presented a case involving a 34-year-old woman who was diagnosed with mediastinal EIMS and had a rare echinoderm microtubule-associated protein-like 4 (EML4) -ALK fusion. Following 15 months of neoadjuvant lorlatinib treatment, the patient underwent a complete surgical resection, resulting in a pathological complete response. Given the heightened risk of postoperative recurrence associated with EIMS, the patient's treatment plan included ongoing adjuvant therapy with lorlatinib. As of the present moment, the patient has achieved an overall survival of over 2 years with no observed tumor recurrence. Consequently, the case offers valuable clinical evidence supporting the potential benefits of neoadjuvant lorlatinib treatment for ALK-positive locally mediastinal EIMS patients, with a demonstrated tolerable safety profile.Copyright © 2024 Zheng, Zhao, Ren, Xue, Yan and Huang.