Clinical study on gefitinib combined with γ-ray stereotactic body radiation therapy as the first-line treatment regimen for senile patients with adenocarcinoma of the lung (final results of JLY20080085)

Abstract

Lung cancer is one of the most commonly encountered human malignancies. Due to the increase in life expectancy as well as the incidence of lung cancer, the incidence of senile lung cancer has increased significantly. We conducted a study to evaluate the efficacy and safety of gefitinib combined with γ-ray stereotactic body radiation therapy (SBRT) as the first-line treatment regimen for senile patients with adenocarcinoma of the lung. A total of 122 senile patients with adenocarcinoma of the lung were divided into 3 groups according to the treatment method. Group A included 35 patients treated with gefitinib combined with γ-ray SBRT, group B included 45 patients treated with γ-ray SBRT alone and group C included 42 patients treated with gefitinib alone. The patients received 250 mg of gefitinib per day, from the first day of the treatment until disease progression or discontinuation due to other causes. The patients were treated with γ-ray SBRT, initiated on the second day. The dose curve for this case group was 50–80%. The encircled dose was 4.0–6.5 Gy per fraction and the range of the total radiation dose was 36–48 Gy. The total number of treatments was 8–12, at a frequency of 5 times per week. All 122 patients were assessed by contrast-enhanced double helical computed tomography (CT) at 2 months. The tumor response rate (RR) of group A was 68.6% (24/35), the disease control rate (DCR) was 88.6% (31/35), the median overall survival (OS) was 15.5 months (range, 3–52 months) and the progression-free survival (PFS) was 7.8 months. The 1-year OS rate was 40.0% (14/35). The main side effects included skin rash and diarrhea. The RR of group B was 51.1% (23/45), the DCR was 71.1% (32/45), the OS was 9.6 months (range, 3–22 months) and the PFS was 5.3 months. The 1-year OS rate was 15.6% (7/45). The RR of group C was 40.5% (17/42), the DCR was 61.9% (26/42), the OS was 10.3 months (range, 3–26 months) and the PFS was 5.1 months. The 1-year OS rate was 35.7% (15/42). The main side effects included skin rash and diarrhea. The short-term therapeutic effect (RR) in group A was higher compared to that in group C (P=0.014, χ2=6.053); however, there was no significant difference compared to group B (P=0.116, χ2=2.477). The PFS of group A was higher compared with that of groups B and C (7.8 vs. 5.9, P=0.018 and 7.8 vs. 5.1, P=0.013, respectively). The OS of group A was higher compared with that of groups B and C (15.5 vs. 9.6, P=0.002 and 15.5 vs. 10.3, P=0.017, respectively). No significant differences were observed in PFS and OS between groups B and C. In conclusion, gefitinib combined with γ-ray SBRT appears to be feasible and effective as the first-line treatment in senile patients with adenocarcinoma of the lungs.