Effect of Recombinant Human Endostatin on Radiosensitivity in Patients With Non–Small-Cell Lung Cancer

Abstract

To observe the effects of recombinant human endostatin (RHES) on the radiosensitivity of non-small cell lung cancer (NSCLC). First, 10 hypoxia-positive cases of pathology-diagnosed NSCLC selected from 15 patients were used to determine the normalization window, a period during which RHES improves NSCLC hypoxia. Second, 50 hypoxia-positive cases of pathology-diagnosed NSCLC (Stages I-III) were randomly divided into a RHES plus radiotherapy group (25 cases) and a radiotherapy-alone group (25 cases). Intensity = modulated radiotherapy with a total dose of 60 Gy in 30 fractions for 6 weeks was adopted in the two groups. The target area included primary foci and metastatic lymph nodes. In the RHES plus radiotherapy group, RHES (15 mg/day) was intravenously given during the normalization window. After RHES administration, the tumor-to=normal tissue radioactivity ratio and capillary permeability surface were first decreased and then increased, with their lowest points on the fifth day compared with the first day (all p < 0.01). Blood flow was first increased and then decreased, with the highest point on the fifth day, compared with the first and tenth day (all p< 0.01). In the RHES plus radiotherapy group and the radiotherapy-alone group, the total effective rates (complete response plus partial response) were 80% and 44% (p = 0.009), respectively. The median survival times were 21.1 ± 0.97 months and 16.5 ± 0.95 months (p= 0.004), respectively. The 1-year and 2-year local control rates were 78.9 ± 8.4% and 68.1 ± 7.8% (p = 0.027) and 63.6 ± 7.2% and 43.4 ± 5.7% (p = 0.022), respectively. The 1-year and 2-year overall survival rates were 83.3 ± 7.2% and 76.6 ± 9.3% (p = 0.247) and 46.3 ± 2.4% and 37.6 ± 9.1% (p = 0.218), respectively. The RHES normalization window is within about 1 week after administration. RHES combined with radiotherapy within the normalization window has better short-term therapeutic effects and local control rates and no severe adverse reactions in the treatment of NSCLC, but it failed to significantly improve the 1-year and 3-year overall survival rates.