Results
A total of 9112 pediatric and AYA sarcoma cases were included in this
study. The demographic and clinical characteristics of the population
are shown in Table 1. The majority of patients were white (75.9%) and
non-Hispanic (80.1%) with a median age at diagnosis of 17 years.
Primary tumors were most commonly in the extremities (39.1%). Of the
total study population, 2932 (32.1%) patients were classified as having
low SES, 2084 (22.8%) with middle SES, and 4096 (44.9%) with high SES.
The low SES category had a higher proportion of black (26.4%) and
Hispanic patients (21.7%) as compared to the high SES category.
There were significant differences in the proportion of patients in each
SES category who presented with advanced disease at diagnosis. For
patients with low SES, 18.6% had metastatic disease compared to 16.9%
in the middle SES category and 15.7% in the high SES
(p<0.01). A similar trend was found with increased tumor size,
where 53.1% of low SES, 51.6% of middle SES, and 48.4% of high SES
patients presented with a tumor that was ≥5cm (p<0.01). The
median time to treatment was 5 days (IQR 0-20). Only low SES was
associated with an increased median time to treatment of 6 days (IQR
0-22, p<0.01). Most patients received chemotherapy (60.1%),
44.4% received radiation therapy, and 71.8% underwent surgery. More
patients in the highest SES category lived in a metropolitan area
compared to low SES (90.4% vs. 74.9%, p<0.01) and less than
60 miles from the facility where they received treatment (82.5% vs.
74.4%, p<0.01).
The results of the univariate and multivariate analysis are presented in
Table 2. In the univariate analysis, black race was significantly
associated with an increased risk of tumor size ≥5cm compared to white
(OR=1.36, p<0.01), but not for the presence of metastatic
disease. Significant univariate predictors of metastatic disease
included low SES (OR=1.23, p<0.01), public or no insurance
(OR=1.34, p<0.01 and OR=1.42, p<0.01, respectively).
Low and middle SES were significantly associated with an increased risk
of a tumor ≥5 cm (OR=1.37, p<0.01 and OR=1.23,
p<0.01, respectively) along with both public and no insurance
(OR=1.34, p<0.01 and OR=1.92, p<0.01, respectively).
Additionally, odds ratios increased with age, with patients in the
13-25-year category 1.96 times more likely to present with metastatic
disease and 1.34 times more likely to present with a tumor ≥5 cm.
After accounting for significant variables of interest, our multivariate
analysis showed that low SES and public and no insurance remained
significant predictors of advanced disease at diagnosis. Compared to
high SES, patients with low SES had a 16% increase in the odds of
presenting with metastatic disease (p=0.03), and 29% increased odds of
presenting with tumor size ≥5cm (p<0.01). Middle SES showed a
17% increase in odds of tumor size ≥5cm compared to high SES (p=0.01),
but no difference in metastatic disease (p=0.37). Compared to private
insurance, public insurance was associated with metastatic disease (OR=
1.35, p<0.01) and increased tumor size (OR=1.28,
p<0.01). Additionally, lack of insurance was associated with
increased odds ratios of presenting with metastatic disease (OR=1.32,
p=0.02) and larger tumor size (OR=1.67, p<0.01).