Department of Radiation Oncology, Nelune Comprehensive Cancer Centre, Prince of Wales Hospital and Community Health Services, Level 1, Bright Building, Avoca St, Randwick, NSW, 2031, Australia.
School of Clinical Medicine, Randwick Campus, Faculty of Medicine and Health, University of New South Wales, Randwick, NSW, 2031, Australia.
Eur Arch Otorhinolaryngol. 2023 Dec;280(12):5583-5594. doi: 10.1007/s00405-023-08162-y. Epub 2023 Aug 12.
Computed tomography (CT)-defined sarcopenia, as a measurement of low skeletal muscle (SM), is a poor prognostic indicator in patients with head and neck cancer (HNC), independent of weight or nutritional status. We used SM measures at the second thoracic vertebra (T2) to determine T2-SM index (SMI) thresholds for sarcopenia, and investigate the impact of low T2-SMI on overall survival (OS), and weight loss during radiotherapy (RT).
Adult patients with newly diagnosed HNC with a diagnostic PET-CT or RT planning CT scan were included. SM was analysed at T2 and a model applied to predict SM at L3. T2-SMI thresholds for sarcopenia were established with predicted measures, stratified by BMI and sex. Impact of sarcopenia and low T2-SMI on OS and weight loss during RT was investigated.
A total of 361 scans were analysed (84% males, 54% oropharynx tumours). Sarcopenia was found in 49%, demonstrating worse OS (p = 0.037). T2-SMI cutoff values were: females-74 cm/m [area under the curve (AUC): 0.89 (95%CI 0.80-0.98)], males (BMI < 25)-63 cm/m [AUC 0.93 (95%CI 0.89-0.96)], males (BMI ≥ 25)-88cm/m [AUC 0.86 (95%CI 0.78-0.93)]. No difference in OS with T2-SMI categories. Lowest T2-SMI quartile of < 63 cm/m demonstrated worse OS (p = 0.017). Weight loss during RT was higher in patients; who were not sarcopenic (6.2% vs 4.9%, p = 0.023); with higher T2-SMI (6.3% vs 4.9%, p = 0.014) and; in the highest quartiles (3.6% vs 5.7% vs 7.2%, p < 0.001).
These T2-SMI thresholds are effective in assessing CT-defined sarcopenia in HNC. Further assessment of clinical application is warranted.
计算机断层扫描（CT）定义的肌肉减少症是头颈部癌症（HNC）患者预后不良的指标，独立于体重或营养状况。我们使用第 2 胸椎（T2）的肌肉量来确定 T2 肌肉减少症指数（SMI）的截值，以研究低 T2-SMI 对总生存率（OS）和放疗期间体重减轻的影响。
纳入了新诊断为 HNC 的成年患者，他们有诊断性 PET-CT 或放疗计划 CT 扫描。在 T2 处分析肌肉量，并应用模型预测 L3 处的肌肉量。根据 BMI 和性别分层，用预测值建立肌肉减少症的 T2-SMI 截值。研究肌肉减少症和低 T2-SMI 对 OS 和放疗期间体重减轻的影响。
共分析了 361 个扫描（84%为男性，54%为口咽肿瘤）。发现 49%的患者存在肌肉减少症，OS 更差（p=0.037）。T2-SMI 截断值为：女性-74cm/m[曲线下面积（AUC）：0.89（95%CI 0.80-0.98）]，男性（BMI<25）-63cm/m[AUC 0.93（95%CI 0.89-0.96）]，男性（BMI≥25）-88cm/m[AUC 0.86（95%CI 0.78-0.93）]。T2-SMI 分类与 OS 无差异。最低的 T2-SMI 四分位数<63cm/m 的患者 OS 更差（p=0.017）。放疗期间体重减轻更多的患者；非肌肉减少症患者（6.2%比 4.9%，p=0.023）；T2-SMI 较高的患者（6.3%比 4.9%，p=0.014）；T2-SMI 最高四分位数的患者（3.6%比 5.7%比 7.2%，p<0.001）。
这些 T2-SMI 截断值可有效评估 HNC 的 CT 定义肌肉减少症。需要进一步评估其临床应用。
