48MO - Characteristics and outcomes of 76 patients with pleomorphic liposarcoma: The Gustave Roussy experience

Background

Pleomorphic liposarcoma (P-LPS), a rare high-grade subtype of sarcomas, is the less common among liposarcomas. Management of P-LPS is based on guidelines for other types of sarcomas. There is an unmet need for specific data on P-LPS from experienced centers due to their unique features. This paper aims to evaluate the clinical characteristics and treatment outcomes of P-LPS patients with emphasis on survival data and response to systemic therapy.

Methods

This is a retrospective analysis of all P-LPS pts at Gustave Roussy from March 1988 to July 2022. Clinical and demographic data, as well as survival outcomes, were retrieved from electronic records. Additional data on response to systemic therapy were also gathered.

Results

76 P-LPS patients (pts) were included. There were 41 women (53.9%) and the mean age was 57 years (16-85). 59 pts had localized disease (77.6%) at diagnosis and the majority (97.2%) had grade 2 or 3 tumors. The most common primary site was in the lower limbs (41.5%) followed by the upper limbs and the trunk (20.8% and 19.5%, respectively). The median local-RFS (relapse-free survival) at 1 and 5 years were 81.1% and 50.1% while the metastatic RFS was 85.4% and 64.8%, respectively. On multivariate analysis (MA), age and gender were found to be prognostic factors for local recurrence while only tumor grade was for distant relapse. Overall survival in the whole population at 1 and 5 years was 95.6% and 74.9%, respectively. Adjuvant chemotherapy (21 out of 71 pts) was a negative prognostic biomarker for OS on MA. Among 25 pts with advanced disease, response rates were higher with eribulin (in 4 pts, ORR=25% and DCR=75%) and trabectedin (in 7 pts; ORR=57% and DCR=86%) in the first or later lines of therapy, in comparison to conventional chemotherapy (doxorubicin-based; in 17 pts, ORR=5.9% and DCR=47%). In the first-line setting, the ORR reached 13.6% versus 8.3% in the second-line setting.

Conclusions

P-LPS is a rare and aggressive entity with a high risk of local and distant recurrence. In the advanced setting, Eribulin and trabectedin showed significant activity in comparison to conventional therapy. Larger multicentric data collection with better identification of molecular characteristics is needed to optimize the management of this entity.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.