Clinical research of intercalated combination of osimertinib and docetaxel in T790M mutation-positive lung adenocarcinoma patients with bone metastasis in the southern Hainan Province

Objective To study the clinical application of intercalated combination of osimertinib and docetaxel in T790M mutation-positive lung adenocarcinoma patients with bone metastasis in the southern Hainan Province. Methods T790M mutation-positive lung adenocarcinoma patients with bone metastasis in the sou-thern Hainan Province treated at the Third People′s Hospital of Hainan Province from January 2018 to October 2018 were enrolled, and they were divided into intercalated combination of osimertinib and docetaxel group (n=32) and osimertinib group (n=28) according to the treatment. The patients in intercalated combination of osimertinib and docetaxel group received oral osimertinib (80 mg, qd), and received docetaxel (75 mg/m2, repeated in three-week intervals) when taking to tumor progression, and oral osimertinib treatment (80 mg, qd) was maintained until tumor partial response or stable disease after chemotherapy. The patients in osimertinib group received oral osimertinib (80 mg, qd). The patients in both groups received zoledronic acid. The response rate, disease control rate, overall survival (OS) and the incidence of adverse reactions of both groups were contrastively analyzed. Results The response rate of intercalated combination of osimertinib and doceta-xel group (62.5%, 20/32) was higher than that of osimertinib group (35.7%, 10/28), and disease control rate (93.8%, 30/32) was also higher than that of osimertinib group (67.9%, 19/28), with statistically significant differences (χ2=4.286, P=0.038; χ2=6.687, P=0.010). The median OS of intercalated combination of osimertinib and docetaxel group was 10.0 months, which was longer than that of osimertinib group (9.0 months), with statistically significant difference (χ2=5.917, P=0.015). Moreover, the adverse reactions in both groups were all grade Ⅰ or Ⅱ, which could be relieved or improved through symptomatic treatment. Conclusion Intercalated treatment of osimertinib with docetaxel is safe and effective in T790M mutation-positive lung adenocarcinoma patients with bone metastasis in the southern Hainan Province. It can prolong the survival time of patients. Key words: Lung neoplasms; Osimertinib; Docetaxel; Bone metastasis; Southern Hainan Province