J Cancer 2018; 9(21):3831-3838. doi:10.7150/jca.25715
Retroperitoneal dedifferentiated liposarcoma: Analysis of 61 cases from a large institution
1. Department of Bone and Soft Tissue Sarcomas, Fudan University Shanghai Cancer Center, Shanghai, China
2. Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
*Peng Luo and Weiluo Cai contributed equally to this work.
Luo P, Cai W, Yang L, Wu Z, Chen Y, Zhang R, Yan W, Shi Y, Wang C. Retroperitoneal dedifferentiated liposarcoma: Analysis of 61 cases from a large institution. J Cancer 2018; 9(21):3831-3838. doi:10.7150/jca.25715. Available from https://www.jcancer.org/v09p3831.htm
Background: To describe the clinical features of retroperitoneal dedifferentiated liposarcoma (RP DDLS) and further evaluate the prognostic factors.
Methods: The clinicopathological variables and treatment strategies of 61 RP DDLS patients who underwent surgical resections at a single institution between September 2005 and September 2016 were reviewed. Kaplan-Meier and Cox regression methods were conducted for survival analyses.
Results: The average patients' age was 52 years (range, 27-81), and there was almost no gender predilection (30 males vs. 31 females). 51 (83.6%) patients got gross tumor resections (R0/R1 resection), and the median tumor size was 19 cm (range, 4.3-50 cm). 39(63.9%) patients were with intermediate-grade sarcoma and 22(36.1%) were with high-grade sarcoma. The median intraoperative blood loss was 400 ml (range, 50-2700ml). 19 (31.1%) patients presented multifocal diseases. Tumors were removed intactly in 42 (68.9%) patients. In order to obtain gross tumor resections, 33 (54.1%) of the patients underwent excisions of at least one adjacent organ, of which kidney (n=21, 63.6%) was the most common one. 6 (9.8%) patients developed distant metastases during follow-up. The overall 5-year progression-free survival (PFS) rate was 3.7%, with the median PFS of 19 months. The 5-year overall survival (OS) rate was 43.5%, with the median OS of 58 months. Updating to November 2017, 30 (49.2%) patients remained alive. The median follow-up time was 49 months. Multivariate analysis using Cox proportional hazards model revealed that tumor grade, blood loss, resection extent, and tumor integrity were independently associated with OS (p=0.032, p=0.018, p=0.020, p=0.005, respectively). Tumor grade, tumor integrity and multifocality were significant predictors for PFS (p=0.013, p=0.080, p=0.009, p=0.028, respectively).
Conclusion: Intermediate-grade histology, intraoperative blood loss < 400 ml, complete tumor resection, and tumor integrity were independently associated with better OS. Intermediate-grade histology, tumor integrity and unifocal disease independently predicted favorable PFS.
Keywords: retroperitoneal dedifferentiated liposarcoma, Asian, predictors