BACKGROUND Selective neck dissection (SND) is a mainstay of head and neck cancer treatment. A common sequela is shoulder syndrome from spinal accessory nerve (SAN) trauma. Extensive dissection in neck levels 2 and 5 leads to SAN dysfunction. However, it is not known whether limited level 2 dissection reduces SAN injury. The purpose of this double-blind randomized controlled trial was to determine whether omitting level 2b dissection would improve shoulder-related quality of life and function. METHODS Patients with head and neck cancers undergoing surgery were randomized 1:1 to SND without level 2b dissection (group 1) or with it (group 2) on their dominant-hand side. Patients, caregivers, and assessors were blinded. The primary outcome was the change in the Neck Dissection Impairment Index (NDII) score after 6 months. An a priori calculation of the minimally important clinical difference in the NDII score was determined to establish a sample size of 15 patients per group (power = 0.8). Secondary outcomes included shoulder strength and range of motion (ROM) and SAN nerve conduction. The trial was registered at ClinicalTrials.gov (NCT00765791). RESULTS Forty patients were enrolled, and 30 were included (15 per group). Six months after the surgery, group 2 demonstrated a significant median decrease in the NDII from the baseline (30 points) and in comparison with group 1, whose NDII dropped 17.5 points (P = .02). Shoulder ROM and SAN conduction demonstrated significant declines in group 2 (P ≤ .05). No adverse events occurred. CONCLUSIONS Level 2b should be omitted in SND when this is oncologically safe and feasible. This allows for an optimal balance between function and cancer cure.

中文翻译：

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2b还是2b？2b级颈淋巴清扫术后的肩部功能：一项双盲随机对照临床试验。

背景技术选择性颈淋巴清扫术（SND）是头颈癌治疗的主要手段。常见的后遗症是脊柱副神经（SAN）创伤引起的肩综合症。颈部第2级和第5级的广泛解剖会导致SAN功能障碍。但是，尚不知道有限的2级解剖是否可以减轻SAN损伤。这项双盲随机对照试验的目的是确定省略2b级解剖是否会改善与肩膀相关的生活质量和功能。方法将接受手术治疗的头颈癌患者以1：1的比例随机分为SND，无2b级夹层清扫术（第1组）或优势侧加第2b夹层清扫术（第2组）。患者，护理人员和评估者不知情。主要结果是6个月后颈部清扫障碍指数（NDII）得分的变化。对NDII评分中最小的重要临床差异进行先验计算，以确定每组15名患者的样本量（功效= 0.8）。次要结果包括肩部力量和运动范围（ROM）和SAN神经传导。该试验已在ClinicalTrials.gov（NCT00765791）上进行了注册。结果纳入40例患者，其中30例（每组15例）被纳入研究。手术六个月后，第2组显示NDII较基线有显着中位数下降（30分），而与第1组相比，NDII下降了17.5分（P = .02）。肩部ROM和SAN传导在第2组中显示出显着下降（P≤.05）。没有发生不良事件。结论在肿瘤学上安全可行的情况下，应在SND中省略2b级。