Sjøblom Bjørg, Grønberg Bjørn H, Wentzel-Larsen Tore, Baracos Vickie E, Hjermstad Marianne J, Aass Nina, Bremnes Roy M, Fløtten Øystein, Bye Asta, Jordhøy Marit
Dept of Internal Medicine, Innlandet Hospital Trust, Hamar, Norway; Dept of Oncology, Oslo University Hospital, Oslo, Norway.
The Cancer Clinic, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway; European Palliative Care Research Centre, Dept of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
Clin Nutr. 2016 Dec;35(6):1386-1393. doi: 10.1016/j.clnu.2016.03.010. Epub 2016 Apr 1.
BACKGROUND & AIMS: Recent research indicates that severe muscular depletion (sarcopenia) is frequent in cancer patients and linked to cachexia and poor survival. Our aim was to investigate if measures of skeletal muscle hold prognostic information in advanced non-small cell lung cancer (NSCLC).
We included NSCLC patients with disease stage IIIB/IV, performance status 0-2, enrolled in three randomised trials of first-line chemotherapy (n = 1305). Computed tomography (CT) images obtained before start of treatment were used for body composition analyses at the level of the third lumbar vertebra (L3). Skeletal muscle mass was assessed by measures of the cross sectional muscle area, from which the skeletal muscle index (SMI) was obtained. Skeletal muscle radiodensity (SMD) was measured as the mean Hounsfield unit (HU) of the measured muscle area. A high level of mean HU indicates a high SMD.
Complete data were available for 734 patients, mean age 65 years. Both skeletal muscle index (SMI) and muscle radiodensity (SMD) varied largely. Mean SMI and SMD were 47.7 cm/m and 37.4 HU in men (n = 420), 39.6 cm/m and 37.0 HU in women (n = 314). Multivariable Cox regression analyses, adjusted for established prognostic factors, showed that SMD was independently prognostic for survival (Hazard ratio (HR) 0.98, 95% CI 0.97-0.99, p = 0.001), whereas SMI was not (HR 0.99, 95% CI 0.98-1.01, p = 0.329).
Low SMD is associated with poorer survival in advanced NSCLC. Further research is warranted to establish whether muscle measures should be integrated into routine practice to improve prognostic accuracy.
近期研究表明，严重肌肉消耗（肌肉减少症）在癌症患者中很常见，且与恶病质及不良生存状况相关。我们的目的是研究骨骼肌指标是否对晚期非小细胞肺癌（NSCLC）具有预后信息价值。
我们纳入了疾病分期为IIIB/IV期、体能状态为0 - 2的NSCLC患者，这些患者参与了三项一线化疗的随机试验（n = 1305）。治疗开始前获得的计算机断层扫描（CT）图像用于第三腰椎（L3）水平的身体成分分析。通过测量肌肉横截面积来评估骨骼肌质量，并由此获得骨骼肌指数（SMI）。骨骼肌放射密度（SMD）通过测量肌肉区域的平均亨氏单位（HU）来测定。平均HU值高表明SMD高。
734例患者有完整数据，平均年龄65岁。骨骼肌指数（SMI）和肌肉放射密度（SMD）差异很大。男性（n = 420）的平均SMI和SMD分别为47.7 cm/m和37.4 HU，女性（n = 314）分别为39.6 cm/m和37.0 HU。在对既定预后因素进行调整的多变量Cox回归分析中，显示SMD对生存具有独立预后价值（风险比（HR）0.98，95%置信区间0.97 - 0.99，p = 0.001），而SMI则不然（HR 0.99，95%置信区间0.98 - 1.01，p = 0.329）。
低SMD与晚期NSCLC患者较差的生存状况相关。有必要进一步研究以确定肌肉指标是否应纳入常规实践以提高预后准确性。
