Abstract 127P
Background
There is sparse data about the outcomes of advanced chordoma on targeted therapies. Subtyping morphologically/genomically is also less studied.
Methods
Retrospective analysis of a prospective database of chordoma patients referred to Sarcoma Medical Oncology Clinic, AIIMS, Delhi between January 2017 to December 2022. SPSS 23 was used for analysis.
Results
There were 23 patients (pts) with male predominance (n=16, 70%). Age ranged from 3 months to 69 years with median age 48 years with 3 pts (13%) less than 18 years of age. The majority (n=22, 96%) had chondroid chordoma while 1 had poorly differentiated with INI 1 loss. Most common sites were sacral n=12, vertebral n=6, clival n=5. Of 23, 7 (30%) had the metastatic disease while 16 (70%) had locally advanced disease. Brachyury positivity was present in all pts. EGFR IHC was done in 10 pts and was positive in all with 5 showing strong EGFR positivity. Median number of previous surgeries done was 1 (range= 1- 3) while 12 (52%) had received radiotherapy. 4 patients had received imatinib before presenting to our clinic. In our clinic, first-line therapies were erlotinib, n=13 (56%) while sirolimus was first-line therapy for TSC2 mutated chordoma (n=1), imatinib (n=1), and doxorubicin-based chemotherapy was considered for INI deficient chordoma(n=1). Others received best supportive care (n=1), resurgery +/- radiation therapy (n=3) and carbanion therapy (Austria), (n=1). Of those on erlotinib in which response was assessed (n=12), RECIST response was 41% and the median PFS was 15 months. Sirolimus also led to partial response in a patient with TSC2 mutation persisting beyond 9 months. 2 pts progressing on erlotinib were given afatinib and had SD for 7 months and 11 months. 1 pt with MET amplification is on cabozantinib with clinical improvement. Next-generation sequencing was done in 5 patients and revealed germline and somatic TSC2 mutation (n=1), PIK3CA mutation (n=1), MET amplification (n=1), and others (n=2).
Conclusions
Advanced chordoma is a heterogenous entity with evolving strategies. EGFR receptors including erlotinib and afatinib are effective drugs while TSC 2 mutated chordoma may respond to mTOR inhibitors. Such rare diseases need collaboration and research on a global level.
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.