1492P - The differences in recurrence and survival of extremity liposarcoma subtypes

Date 11 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Soft Tissue Sarcomas
Sarcoma
Presenter Melissa Vos
Citation Annals of Oncology (2017) 28 (suppl_5): v521-v538. 10.1093/annonc/mdx387
Authors M. Vos1, H. Kosela Paterczyk2, P. Rutkowski2, G.J.L.H. van Leenders3, M. Normantowicz4, A. Lecyk4, S. Sleijfer5, K. Verhoef6, D.J. Grünhagen6
  • 1Medical Oncology/surgical Oncology, Erasmus MC Cancer Institute, 3075 EA - Rotterdam/NL
  • 2Soft Tissue/bone Sarcoma And Melanoma, The Maria Sklodowska-Curie Memorial Institute and Oncology Centre, 02-781 - Warsaw/PL
  • 3Pathology  , Erasmus MC Cancer Institute, Rotterdam/NL
  • 4First Faculty Of Medicine, Medical University of Warsaw, Warsaw/PL
  • 5Medical Oncology, Erasmus MC Cancer Institute, Rotterdam/NL
  • 6Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam/NL

Abstract

Background

Liposarcomas (LPS) are most frequently located in the extremity and recur often, locally as well as on distant sites. There are currently no studies comparing the differences between the different LPS subtypes specifically on this primary site. The aim of this study is to map the differences in recurrence and survival of extremity LPS.

Methods

Two retrospective databases (Rotterdam-R, Warsaw-W) of patients treated for primary LPS located in the extremities from 1985-2015 in two tertiary referral centers were used to analyze recurrence patterns (local/distant) and survival.

Results

In total, 456 patients were identified: 192 with well differentiated LPS (WDLPS), 172 myxoid LPS (MLPS), 54 pleomorphic LPS (PLPS), 23 dedifferentiated LPS(DDLPS) and 15 other subtypes (excluded from further analysis). A difference between the two datasets was the frequency of (neo)adjuvant radiotherapy (R: 34.9% vs. W: 81.5%). In the Rotterdam cohort, local recurrence (LR) was observed most frequent in DDLPS (4/13, 5-year LR free survival 56.6%), followed by WDLPS (26/113, 64.9%), PLPS (3/20, 78.6%) and MLPS (10/77, 84.0%, p = 0.136). In the Warsaw cohort, 5-year LR free survival was the lowest in PLPS (9/34, 67.7%), followed by DDLPS (1/10, 83.3%), MLPS (12/95, 84.9%) and WDLPS (3/79, 94.1%, p = 0.001). Distant metastases (DM) were most commonly observed in PLPS in both datasets (5-year DM free survival R: 9/20, 50.3% and W: 16/34, 44.5%), but in the Rotterdam cohort MLPS (16/77, 76.3%) was the second most common subtype with DM, compared to DDLPS (2/10, 62.5%) in Warsaw. DM in WDLPS was rare in both datasets (R:3/113, 96.3%, W: 1/79, 98.5%). 5-year overall survival (OS) did not significantly differ between the two datasets (R: 38/223, 78.5% vs. W: 32/218, 80.9%, p = 0.561), but did significantly differ between the subtypes (R: p = 0.005, W: p 

Conclusions

Patients with the four LPS subtypes show distinct patterns of LR, DM and OS. Despite the differences in recurrence, treatment and follow up, OS did not differ significantly between the two expertise centers.

Clinical trial identification

Legal entity responsible for the study

Erasmuc MC Rotterdam

Funding

None

Disclosure

All authors have declared no conflicts of interest.