Changes in radiation therapy practice and cancer incidence bring into question prior evidence suggesting that radiation therapy predominantly injures the brachial plexus upper trunk, while tumor invasion typically injures the lower trunk.

中文翻译：

---

原发癌的位置预示着臂丛神经病变的主要水平。

放射治疗实践和癌症发生率的变化使以前的证据受到质疑，这些证据表明放射治疗主要伤害臂丛神经上躯干，而肿瘤的入侵通常会伤害下躯干。