Opportunistic muscle measurements on staging chest CT for extremity and truncal soft tissue sarcoma are associated with survival

Abstract

Background and Objectives Computed tomography (CT) measurements of sarcopenia have been proposed as biomarkers associated with outcomes in various cancers and have typically been evaluated at the L3 vertebral level. However, staging imaging for patients with extremity and truncal soft tissue sarcoma (STS) often only includes chest CT imaging which precludes evaluation at L3. Therefore, we sought to evaluate muscle metrics at T12 on standard staging chest CT scans and evaluate for correlation with overall and event‐free survival in patients with STS. Methods CT chest imaging for 89 patients with intermediate and high‐grade STS (53 male, 36 female; 58.5 ± 19.0 years old, follow‐up 37.4 ± 27.1 months) was reviewed on PACS at T12 for skeletal muscle density (SMD) and skeletal muscle index (SMI). Results Overall survival increased with increased SMD on univariate (hazard ratio [HR] = 0.61 [0.43, 0.86]) and age‐adjusted analysis (HR = 0.65 [0.42, 0.89]. Event‐free survival also increased with increased SMD in univariate analyses (HR = 0.68 [0.49, 0.95]) but did not maintain significance after adjusting for age (HR = 0.68 [0.43, 1.07]). SMI was not a predictor of overall or event‐free survival. Conclusions Higher SMD measured on routinely obtained staging chest CTs in STS patients is associated with improved survival.

Impact of sarcopenia in advanced and metastatic soft tissue sarcoma

“…Comparability is limited though, because different to our study, that study investigated localized as well as metastatic disease. In two other analyses with higher proportions of patients with more advanced disease, association of sarcopenia with OS was found [33,34]. Therefore, the impact of sarcopenia seems to be more significant in a/mSTS compared to localized disease stages and this might be attributed to higher levels of inflammation found in advanced and metastatic disease linked to cancer cachexia [35].…”

“…Another possible source of deviation in reported SMI values may be attributed to the use of different software solutions. In this study a self-designed, purpose-built albeit unvalidated software within the MeVisLAB framework is utilized, whereas other studies use commercially available software solutions [33,34].…”

Impact of preoperative sarcopenia in patients undergoing sacral tumor resection

“…However, the authors noted that patients with sarcopenia were noted to have larger tumor size, and larger tumor size was also associated with mortality 19 . Likewise, a series by Phan et al 17 recently utilized the skeletal muscle density measured at the T12 vertebral body to show that patients with a higher skeletal muscle density (less cachexia) had improved survival following sarcoma surgery. In the current series, however, we did not notice an impact of sarcopenia on survival.…”

“…[26][27][28] In patients with bone and soft-tissue sarcomas, there have been variations in the impact of sarcopenia on oncologic outcome. 16,17,19 In the first series examining the impact of sarcopenia on the outcome of patients with soft-tissue sarcoma, Wilson et al 16 noted there to be no influence of sarcopenia on patient outcome in terms of complications or survival. However, when examining a combined series of bone and soft-tissue sarcomas, Hendrickson et al 19 noted that patients with sarcopenia had worse 12-month survival compared to patients without sarcopenia.…”

“…As a surrogate for the quality of muscle, the psoas:lumbar vertebra index (PLVI) can be obtained on a CT scan 10 . In patients with malignancies, including sarcoma, sarcopenia has been found to be an independent predictor of complications and survival 11–20 . As part of the clinical staging and work‐up of patients undergoing sacral tumor resection, a CT scan of the pelvis is often obtained, 2 and therefore sarcopenia may be easily assessed in this cohort.…”