Factors Impacting Definitive Treatment Management in Adolescent and Young Adults (AYAs) with Extremity Sarcomas

Abstract

A large proportion of extremity soft tissue sarcomas (ESS) occur in the adolescent and young adult (AYA) population, ages 18-39, yet this group is underrepresented in clinical trials. Rare tumors are difficult to study via randomized controlled trials, and the limited data is often extrapolated to AYAs. AYAs present many complex challenges, which affect clinical management. We hypothesized that the National Cancer Database (NCDB) could detect unique factors that influence treatment decisions in AYAs with ESS. The NCDB was utilized to identify patients (pts) 18 and older with ESS diagnosed between 2004-2014 and treated definitively with limb-sparing surgery (LSS) or amputation. Multivariable analyses used logistic regressions for patterns of treatment and their correlation with demographic factors (sex, race, ethnicity, insurance status, income, education, and distance from hospital) and tumor characteristics (primary site, grade, size, clinical stage, depth of extension, and surgical margins). 8953 pts in total were identified and among these, 1280 were AYA. There was no statistical difference in the likelihood of amputation vs. LSS for AYA pts compared to older adults. AYA pts were more likely to receive chemotherapy than older pts (ages 40-65, OR 0.52 (0.45-0.60), p=0.001 and ≥65 years old, OR 0.16 (0.12-0.20), p=0.001). Conversely, AYAs were less likely to receive RT compared to older pts (ages 40-65, OR 1.40 (1.22-1.61), p=0.001 and ≥65 years old, OR 1.33 (1.10-1.61), p=0.003). For all ages, deep tumor extension (OR 1.37 (1.22-1.53), p=0.001) and tumor size (5.01-10 cm, OR 1.30 (1.12-1.51) p=0.001) were associated with the use of RT. Unique to AYAs, clinical stage II disease (compared to stage I, OR 1.25 (0.81-1.91), p=0.313) and positive surgical margins (OR 1.43 (0.93-2.22), p=0.107) were not associated with use of RT. Distance of >10 miles from the hospital was associated with decreased likelihood of receiving RT for all age groups including AYAs. Non-black, Hispanic AYAs were less likely (OR 0.53 (0.36-0.78), p=0.002) compared to those of white race and non-Hispanic ethnicity to receive RT. In addition, AYAs with private insurance were more likely (OR 1.80 (1.19-2.72), p=0.006) than those uninsured to receive RT. Age groups were not significantly associated with the decision to use LSS. However, they do appear to correlate with the decision to use chemotherapy and RT. The AYA population was significantly less likely to receive RT and more likely to receive chemotherapy despite controlling for clinical and demographic factors. Sarcoma disproportionately affects AYAs and further study is warranted to identify the clinical impact of these practice disparities.