Abstract 370P
Background
Brain metastases (BM) develop during the disease course in 20-65% of lung cancer patients. As neo-angiogenesis is crucial to BM growth, the combination of angiogenesis inhibitors and brain radiotherapy is an active focus of research. Apatinib, a tyrosine kinase inhibitor that selectively inhibits the vascular endothelial growth factor receptor-2, is safe and significantly prolongs survival in chemotherapy-refractory gastric cancer. This prospective study evaluated the safety and efficacy of apatinib combined with concurrent whole brain radiation therapy (WBRT) in lung cancer patients with BM.
Methods
Apatinib (500 or 250 mg/day) was administered orally for one week before radiotherapy, and continued in the same manner concurrently with WBRT (15 fractions; 37.5Gy to the whole brain plus a simultaneous integrated boost (SIB) to gross disease of 49.5-52.5Gy) and another week after WBRT completion. The intracranial progression free survival (iPFS), overall survival (OS), brain edema index, intracranial overall response rate (iORR), and intracranial disease control rate (iDCR) were analyzed, and the adverse reactions of the patients were also observed.
Results
From July 2016 to January 2020, 17 patients were treated. At three months after WBRT, the iORR was 70.6%, the iDCR was 88.2%, and brain edema index was significantly reduced compared to before brain radiation therapy (4.2 vs 1.9, P=0.02). The median iPFS time was 9 months (95% CI, 7.1-18.1 months) and the median OS time was 17 months (95% CI, 15.5-37.9 months). The iPFS rates at 6 months, 1 year, and 2 years were 64.7%, 41.2%, and 17.6%, respectively; corresponding OS rates were 76.5%, 70.6%, and 47.1%, respectively. Most patients tolerated apatinib well; 7 patients had side effects, most commonly grade 1 or 2. Only two patients experienced grade 3 adverse events (hypertension and oral mucositis); no grade 4 or 5 toxicities were observed.
Conclusions
Apatinib combined with SIB WBRT appears to be safe and effective in treating BM from lung cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
G. Han.
Funding
National Natural Science Foundation of China (No. 81903137).
Disclosure
All authors have declared no conflicts of interest.