Infantile fibrosarcoma (IFS) is a rare pediatric cancer that typically presents early in life. Surgical resection is commonly curative; however, resection is sometimes not possible requiring additional multimodal treatment. IFS commonly harbors a fusion in one of the neurotrophic receptor tyrosine kinase (NTRK ) genes. Larotrectinib, a highly selective inhibitor of tropomyosin receptor kinase (TRK), has been shown to be well tolerated and effective in children as young as 1‐month old. We report a case of IFS in a newborn treated with larotrectinib. The patient experienced a rapid clinical and radiographic response demonstrating the potential to treat newborns with larotrectinib.

中文翻译：

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使用 larotrectinib 成功治疗了大 NTRK 融合阳性婴儿纤维肉瘤的新生儿。

婴儿纤维肉瘤 (IFS) 是一种罕见的儿科癌症，通常在生命早期出现。手术切除通常可以治愈；然而，有时无法切除，需要额外的多模式治疗。IFS 通常融合了一种神经营养受体酪氨酸激酶 ( NTRK ) 基因。Larotrectinib 是一种高选择性原肌球蛋白受体激酶 (TRK) 抑制剂，已被证明对 1 个月大的儿童具有良好的耐受性和有效性。我们报告了一例接受 larotrectinib 治疗的新生儿发生 IFS 的病例。患者经历了快速的临床和放射学反应，证明了使用 larotrectinib 治疗新生儿的潜力。