Abstract 76P
Background
Leiomyosarcomas are one of the most common types of sarcomas, with an estimated incidence between 10 and 20% of all sarcomas. Unfortunately, despite optimal locoregional treatments, leiomyosarcoma may relapse. At the European level through EORTC, efforts were made to assess different regimens in combination with doxorubicin for the treatment of metastatic unresectable leiomyosarcoma.
Methods
A total of 71 patients treated between 2010-2023 were retrospectively selected, all of whom had provided consent for the use of their data. To obtain a more homogeneous sample, only those patients treated in the first line with anthracyclines in monotherapy or in combination, and gemcitabine and docetaxel were selected from the initially identified group.
Results
A total of 71 patients were retrospectively reviewed, comprising 62 women and 9 men. Age at diagnosis was 53 years (range: 26-86 years). The most common location uterine in 46%. 52,11% (37 patients) exhibited metastatic onset. 64% had pulmonary involvement, predominantly followed by peritoneal localization. Survival in patients with non-metastatic onset, was 58 months (range: 51-64 months), compared to 24 months for metastatic onset (range: 13-34 months), p-value of 0.003. PFSl in different treatment lines: Doxorubicin (D): 8 months, Doxorubicin + dacarbazine(D+DTIC): 12 months, Doxorubicin+trabectedin(D+tra): 9 months, Epirubicin + ifosfamide (Epi+Ifo): 7 month, gemcitabine + docetaxel (Gem+Doc): 7 months and Doxorubicin + olaratumab (D+olara): 7 months, p=0,07. Overall survival (OS) D: 47 months, D+DTIC: 74 months, D+tra 42 month, Epi+Ifo: 30 months, Gem+Doc: 37 months and D+olara: 34 months.
Conclusions
Limitation of retrospective assessment. Slight increase in progression-free survival comparing with the literature. Epi+Ifo should not be a standard option in leiomyosarcoma, as literature data show a low response and limited disease control. However, in our historical series, it was a chosen line in 7 patients. OS, the combination of D+DTIC stands out, doubling overall survival compared to historical data. 86% reach second lines. Assessing PFS2 in treatment, a notable survival of 9 months with tra stands out, surpassing the average and comparing with the trabectedin second-line study showing a PFS of 4.2 months.
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.