The use of the second thoracic vertebral landmark for skeletal muscle assessment and computed tomography‐defined sarcopenia evaluation in patients with head and neck cancer

Abstract

AbstractBackgroundThe cross‐sectional area (CSA) of skeletal muscle (SM) at the third lumbar vertebra (L3) is used to determine computed tomography (CT)‐defined sarcopenia. We investigated the feasibility of SM assessment at the second thoracic vertebra (T2) in patients with head and neck cancer (HNC).MethodsDiagnostic PET‐CT scans were used to develop a prediction model for L3‐CSA using T2‐CSA. Effectiveness of the model and cancer‐specific survival (CSS) were investigated.ResultsScans of 111 patients (85% male) were evaluated. The predictive formula: L3‐CSA (cm2) = 174.15 + [0.212 × T2‐CSA (cm2)] – [40.032 × sex] – [0.928 × age (years)] + [0.285 × weight (kg)] had good correlation r = 0.796, ICC = 0.882 (p < 0.001). SM index (SMI) mean difference (bias) was −3.6% (SD 10.2, 95% CI −8.7% to 1.3%). Sensitivity (82.8%), specificity (78.2%), with moderate agreement (ƙ = 0.540, p < 0.001). Worse 5‐year CSS with lower quartile T2‐SMI (51%, p = 0.003).ConclusionsSM at T2 can be effectively used for CT‐defined sarcopenia evaluation in HNC.