Efficacy of gefitinib and radiotherapy combination in Indonesian patients with lung adenocarcinoma.

INTRODUCTION: Combinations of gefitinib and radiotherapy have been observed to have synergistic and anti-proliferative effects on lung cancer in vitro. In the clinical setting, patients who presented with respiratory difficulties such as superior vena cava syndrome (SVCS), radiotherapy should be given immediately to address the emergency while waiting for the results of epidermal growth factor receptor (EGFR) mutation test. However, there has been no study that described the role of radio-therapy in Indonesian patients with EGFR-mutant lung adenocarcinoma.

METHODS: This preliminary study aimed to evaluate the efficacy and toxicities of gefitinib and radiotherapy combination in lung adenocarcinoma patients in Persahabatan National Respiratory Referral Hospital, Jakarta, Indonesia. Subjects were consecutively recruited between January 2013 and December 2016.

RESULTS: Thirty-one lung adenocarcinoma with EGFR mutations were enrolled. Most of them were male (51.61%) with a median age of 54.5 years old (range 38-70 years old). EGFR mutation characteristics were on exon 21 L858R point mutation (61.30%), exon 21 L861Q point mutation (16.12%) and exon 19 deletion (22.58%). Radiotherapy was given at doses between 30-60 Gy. Among these subjects, median progression-free survival (PFS) was 185 days (95%CI; 123.69 - 246.30), 1-year survival rate (1-yr) was 45.2%, and median overall survival (OS) was 300 days (95%CI; 130.94 - 469.06). There were no grade 3/4 hematological and nonhematological toxicities recorded. The most frequent grade 1 and 2 non-hematological toxicities were skin rash, diarrhea, and paronychia that might be related to tyrosine kinase inhibitor (TKI).

CONCLUSION: The combination of TKI with radiation may be considered in EGFR-mutant lung adenocarcinoma subjects.