Bonm Alipi V, Menghini Anthony, Drolet Caroline E, Graber Jerome J
Department of Neurology, Virginia Mason Franciscan Health, Seattle, Washington, USA.
School of Medicine, University of Washington, Seattle, Washington, USA.
Neurooncol Pract. 2022 Oct 22;10(2):162-168. doi: 10.1093/nop/npac087. eCollection 2023 Apr.
Most patients with primary CNS lymphoma (PCNSL) achieve durable remission whereas a minority die in the first year. Sarcopenia is a powerful predictor of mortality in the brain and systemic cancers. Temporalis muscle thickness (TMT) is a validated radiographic measure of sarcopenia. We hypothesized that patients with thin TMT at diagnosis would have early progression and short survival.
Two blinded operators retrospectively measured TMT in 99 consecutive brain MRIs from untreated patients with PCNSL.
We generated a receiver operator characteristic curve and chose a single threshold defining thin TMT in all patients as <5.65 mm, at which specificity and sensitivity for 1-year progression were 98.4% and 29.7% and for 1-year mortality were 97.4% and 43.5% respectively. Those with thin TMT were both more likely to progress ( < .001) and had higher rates of mortality ( < .001). These effects were independent of the effect of age, sex, and Eastern Cooperative Oncology Group performance status in a cox regression. Memorial Sloan Kettering Cancer Center score did not predict progression-free survival or overall survival as well as TMT. Patients with thin TMT received fewer cycles of high-dose methotrexate and were less likely to receive consolidation but neither variable could be included in the Cox regression due to violation of the proportional hazards assumption.
We conclude that PCNSL patients with thin TMT are at high risk for early relapse and short survival. Future trials should stratify patients by TMT to avoid confounding.
大多数原发性中枢神经系统淋巴瘤（PCNSL）患者可实现持久缓解，而少数患者在第一年死亡。肌肉减少症是脑癌和全身癌症死亡率的有力预测指标。颞肌厚度（TMT）是一种经过验证的肌肉减少症影像学测量指标。我们假设诊断时TMT较薄的患者会出现早期进展且生存期较短。
两名盲法操作者对99例未经治疗的PCNSL患者的连续脑部MRI进行回顾性测量TMT。
我们绘制了受试者工作特征曲线，并选择了一个单一阈值来定义所有患者的TMT较薄情况为<5.65 mm，此时1年进展的特异性和敏感性分别为98.4%和29.7%，1年死亡率的特异性和敏感性分别为97.4%和43.5%。TMT较薄的患者进展的可能性更大（<0.001）且死亡率更高（<0.001）。在Cox回归中，这些影响独立于年龄、性别和东部肿瘤协作组体能状态的影响。纪念斯隆凯特琳癌症中心评分在预测无进展生存期或总生存期方面不如TMT。TMT较薄的患者接受高剂量甲氨蝶呤的周期较少，接受巩固治疗的可能性较小，但由于违反了比例风险假设，这两个变量均不能纳入Cox回归。
我们得出结论，TMT较薄的PCNSL患者早期复发和生存期短的风险较高。未来试验应根据TMT对患者进行分层，以避免混淆。
