Sarcopenia is a negative prognostic factor in localized extremities/trunk wall soft tissue sarcomas

Abstract

Objective: Sarcopenia is an emerging determinant of oncologic patients' prognosis, but few data are available in extremities and trunk wall soft tissue sarcomas (ESTS). The aim was to evaluate sarcopenia impact on outcomes of patients affected by ESTS.

Methods: Through SliceOMatic software we selected cross-sectional skeletal muscle area (SMA), subcutaneous fat area (SFA) and visceral fat area (VFA) on a basal CT-slice at level of the third lumbar vertebra. Muscle density (MD) was computed in Hounsfield units (HU). Skeletal mass index (SMI, cm²/m²) was computed by normalizing SMA for the square of patient's height. Cut-offs for SMI were 52 and 39 cm²/m² for men and women, respectively, while we used median values for MD, SFA and VFA. We explored the correlation of the different parameters with post-surgical complications and survival outcomes (Kaplan-Meier method).

Results: 268 patients were included. Median SMAs, SMIs and MD were 155.7 cm², 51.2 cm²/m², and 33.8 HU for men, 91.4 cm², 39.2 cm²/m², and 30.4 HU for women. Sarcopenia rate was not significantly higher in patients ≥65 years nor according to baseline prognostic factors (Sarculator app). Overall survival (OS) was significantly worse for sarcopenic patients: median OS 111.7 months (95%CI 72.8-150.6) vs not reached (NR; HR = 1.55, 95%CI:1.00-2.41, p = 0.049) for low-vs high-SMI; median OS 79.6 months (38.6-120.6) vs NR (HR 2.11, 1.34-3.34, p = 0.001) for low-vs high-MD, respectively. Sarcopenic patients showed increased post-surgical complications (30.5 % vs 17.0 %, p = 0.073).

Conclusion: Although retrospective, our study suggests to further explore sarcopenia as a negative prognostic factor in ESTS patients.

Keywords: Muscle density; Oncology; Prognostic factors; Sarcopenia; Skeletal mass index; Soft tissue sarcomas.