2999 - Does Social Vulnerability Index Correlate to Adverse Outcomes in Soft Tissue Sarcoma?

R. Jacobson¹, G. Poultsides², V. Grignol³, H. Howard³, K. Chouliaras⁴, K. Votanopoulos⁴, D. Cullinan⁵, R. C. Fields⁶, K. Cardona⁷, and M. Bedi¹; ¹Medical College of Wisconsin, Milwaukee, WI, ²Department of Medicine, Stanford University, Palo Alto, CA, ³Ohio State, Columbus, OH, ⁴Wake Forest, Salem, NC, ⁵Washington University, St. Louis, MO, ⁶Department of Surgery , Washington University School of Medicine, St. Louis, MO, ⁷Emory, Atlanta, GA

Purpose/Objective(s): Social determinants of health play a role in outcomes of many cancers. Socioeconomic and demographic factors have been used to examine disparities in survival among cancer patients, including the CDC Social Vulnerability Index (SVI). Although there is data on SVI in other cancers, the impact of SVI and STS outcomes are poorly understood. The objective of this study was to determine if SVI is associated with recurrence free survival (RFS) and overall survival (OS) in patients with STS. Materials/

Methods: A retrospective study was done using the US Sarcoma Collaborative multi-institutional database from 2000-2016. Age =18 years, stage I-IV extremity and truncal/abdominal wall STS with available zip code data were included. Zip codes were geocoded to the census tract level and matched to social vulnerability values from the CDC SVI. Social vulnerability values ranged from 0-1 with 0 being the least vulnerable and 1 being the most vulnerable. OS and RFS were calculated using Kaplan-Meier survival analyses. Prognostic variables (Table 1) were determined by univariate analysis (UVA) using the log-rank test and multivariate analyses (MVA) using the Cox proportional hazards model.
Results: 511 patients were included in the analysis. Median follow-up was 59 mo. 2-year OS and RFS was 67% and 45%, respectively. Mean nationwide SVI of patients was 0.58 and mean statewide SVI was 0.48 as compared to all censuses. On MVA, any complication (p<0.0001, 95% CI, 48.3-68.3), poor functional status (p=0.02, 95% CI 1.8 -205.3), patients of Hispanic descent (p=0.004, 95% CI 3.1-400.2), high grade (p=0.008, 95% CI 0.06- 0.65), increased tumor size (p<0.0001, 95% CI 1.1-1.6) and high nationwide SVI (p=0.03, 95% CI 1.2- 256.4) were associated with poor OS and stage IV (p=0.006, 95% CI 1.25-3.9), high grade (p=0.04, 95% CI 0.17-0.94) and poor functional status (p=0.0013, 95% CI 4.38 - 456.8) were associated with RFS.
Conclusion: In this study of patients with STS, high SVI was associated with decreased OS. These findings suggest that the SVI may be used as a tool for identifying where resources can be targeted at a national level to mediate the survival disparity for vulnerable populations with sarcoma, however further investigation is warranted.

Abstract 2999 – Table 1: Patient, Tumor and Treatment Characteristics

Variable		n (%)
Age
	=30	52 (8.7)
	31-50	148 (24.7)
	51-70	247 (41.2)
	71-100	153 (25.5)
Gender
	Male	309 (51.5)
	Female	291 (48.5)
Ethnicity
	Asian	17 (2.8)
	Black or African American	67 (11.2)
	Hispanic	38 (6.3)
	White or Caucasian	448 (74.7)
	Other	12 (2.0)
Histology
	Leiomyosarcoma	43 (8.4)
	Liposarcoma	93 (18.2)
	Undifferentiated/pleomorphic sarcoma	168 (32.9)
	Myxofibrosarcoma	48 (9.4)
	MPNST	28 (5.5)
	Extraskelatal myxoid chondrosarcoma	16 (31.3)
	Other	131 (25.6)
Metastasis		170 (28.3)
Grade
	Low	96 (16)
	High	300 (50)
Complications
	Any Complication	122 (20.3)
	No Complications
Readmissions
	= 1 readmission	53 (8.8)
	No readmissions	541 (90.2)
Reoperation
	1 or more reoperations	44 (7.3)
	No reoperations	522 (87)
Chemo
	Yes	89 (14.8)
	No	504 (84)