Tumor cavitation in patients with non-small-cell lung cancer receiving anti-angiogenic therapy with apatinib

Background: Cavities have been reported in approximately 20% of lung cancer after anti-angiogenesis treatments. However, the effect of which on treatment outcomes remains unclear. This study sought to investigate the incidence and radiographic patterns of tumor cavitation in patients with non-small cell lung cancer (NSCLC) treated with apatinib, and its associations with patients' clinical characteristics and outcomes. Methods: A total of 300 patients with NSCLC treated with apatinib were retrospectively identified. Baseline and follow-up chest computed tomography scans were reviewed to identify tumor cavitation, and the subsequent filling-in of the cavitation. A multivariate logistic regression analysis was conducted to identify the factors associated with tumor cavitation. Survival curves were constructed using the KaplanMeier method and compared using the log-rank test. Results: Of the 300 patients, 51 (17.0%) developed lung cavitation after initiating apatinib therapy. The results of the multivariate analysis showed that apatinib combination therapy (vs. apatinib monotherapy, odds ratio: 0.593, 95% confidence interval: 0.412-0.854, P=0.005) was significantly associated with tumor cavitation. Patients with tumor cavitation had significantly longer progression-free survival (PFS) than those without cavitation (8.2 vs. 5.2 months, P<0.01). Of the patients, 18 had cavity filling after progression, while 13 had persistent cavities after progression. The corresponding median PFS times were 11.9 and 3.2 months in patients with filled and persistent cavities after disease progression, respectively (P<0.001). Conclusions: Tumor cavitation occurred in 17% of the NSCLC patients treated with apatinib and was associated with better PFS. Patients who had cavities filled after progression had a better prognosis than those with persistent cavities.