H. N. Overton1, F. Gani1, J. Singh1, A. Blair1, M. Umair3, C. Meyer2, F. M. Johnston1, N. Ahuja1 1Johns Hopkins University School Of Medicine,Division Of Surgical Oncology, Department Of Surgery,Baltimore, MD, USA 2Johns Hopkins University School Of Medicine,Division Of Oncology, Department Of Medicine,Baltimore, MD, USA 3Saint Louis University School Of Medicine,Department Of Radiology,Saint Louis, MO, USA
Introduction:
Retroperitoneal sarcoma (RPS) is a rare tumor type that accounts for approximately 15% of soft tissue sarcomas. An expanding elderly population in the United States presents a need to understand associations between age and outcomes in primary or recurrent RPS. We investigated features of RPS in a cohort of surgical patients to determine if any differences exist along the spectrum of adult age.
Methods:
Patients undergoing surgery for RPS with curative intent at the Johns Hopkins Hospital between 1994 and 2015 were identified. Overall (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meir method. Univariable and multivariable Cox proportional hazards regression analysis was performed to identify factors associated with worse OS and DFS.
Results:
A total of 223 patients were identified who met inclusion criteria. The median age at time of index surgery was 61 years (IQR: 51-68) with 57.5% (n=106) of patients being female. Among all patients, 168 patients (75.3%) presented with primary RPS while 55 (24.6%) presented with recurrent disease. Pathology was 48.9% (n=109) liposarcoma, 34.5% (n=77) leiomyosarcoma, and 16.6% (n=37) other. Median tumor size was 12cm (IQR: 7-20). High grade tumors were most common at 48.8% (n=105) compared to 28.8% (n=62) grade 1 and 22.3% (n=48) grade 2. Complete resection (R0/R1) was achieved in 86.8% (n=191) of patients. Administration of chemotherapy was significantly different among age groups (39.4% <45years, 25.5% 45-64 years, 13.7% 65-79years, 0.00% ≥ 80 years, p=0.007) as was likelihood of an incomplete (R2) resection (21.2% <45years, 6.6% 45-64 years, 16.9% 65-79years, 30.0% ≥ 80 years, p=0.027). Postoperatively, 61.3% (n=119) developed a tumor recurrence; 54.6% (n=65) developed local disease while 38.6% (n=46) developed distant disease and 6.7 % (n=8) developed local and distant disease. The median OS and DFS were 67.5 months (IQR: 27.4-130.6) and 17.8 months (IQR 6.4 -47.4), respectively. On multivariable analysis, increasing patient age was associated with a shorter OS (Hazard Ratio [HR] = 1.02, 95% CI:1.00-1.04, p=0.046) but was not associated with DFS (HR= 1.001, 95% CI:0.98-1.02, p=.879). Of note, other risk factors associated with poor OS were high grade tumor (G1/G2 vs G3) (HR = 2.83, 95% CI:1.47-5.44, p=0.002) and postoperative recurrence (HR= 6.11, 95% CI: 2.92-12.79, p<0.001, Figure 1).
Conclusion:
Increasing age at time of index operation for primary or recurrent RPS, high grade tumor and post-operative recurrence correlates with decreased OS. Further study is needed to understand the characteristics and interactions of pathology, multiple recurrences and aggressive surgical and medical therapy on different age categories of patients with RPS.
