Comparison of clinical and radiological characteristics between anaplastic lymphoma kinase rearrangement and epidermal growth factor receptor mutation in treatment naïve advanced lung adenocarcinoma

Yingying Miao, Suhua Zhu, Huijuan Li, Jiawei Zou, Qingqing Zhu, Tangfeng Lv, Yong Song


Background: Gene analysis could not be performed in all patients, especially in advanced non-small cell lung cancer (NSCLC). We aimed to find some clinical futures and CT or FDG-PET characteristics, which could be combined to help distinguish anaplastic lymphoma kinase (ALK) rearrangement form epidermal growth factor receptor (EGFR) mutations in treatment naïve advanced lung adenocarcinoma of Chinese patients.
Methods: We retrospectively reviewed clinical and radiological characteristics of 145 patients with treatment naïve advanced lung adenocarcinoma. The one-way ANOVA, the Mann-Whitney test, chi-square test and logistic regression were used for comparison between patients with ALK rearrangement and those with EGFR mutation.
Results: Among 145 patients with advanced lung adenocarcinoma, only six patients had both ALK rearrangement and EGFR mutation, the sample size was too small to analysis. Univariate analysis revealed that patients with ALK rearrangement were younger (P=0.001) and with lower serum carcinoembryonic antigen (CEA) level (P=0.008) than those with EGFR mutation. More of tumors with ALK rearrangement were well defined (P=0.023) and have bubble lucency (P=0.026) compared with those with EGFR mutation (P=0.026). Lymphadenopathy was seen more frequently in patients with ALK rearrangement (P=0.167). Twenty-six patients received FDG-PET/CT, among this population, lesion standardized uptake values (SUV) >6.95 and lymph nodes SUVmax >6.25 were more often seen in ALK rearrangement group (P=0.011, both). In multivariate analysis, patients younger than 50 years (RR=9.878, 95% CI: 2.318–42.090, P=0.002), with lower CEA level than 4.95 μg/L (RR=8.166, 95% CI: 1.085–31.983, P=0.003) and without brain metastasis (RR=7.304, 95% CI: 1.099–48.558, P=0.040) were more likely to be ALK rearrangement than EGFR mutation. Tumor diameter less than 36 mm were prone to be EGFR mutation (RR=0.078, 95% CI: 0.017–0.356, P=0.001).
Conclusions: Treatment naïve advanced lung adenocarcinomas with ALK rearrangement were more likely to have younger age, lower serum CEA level, larger tumor volume, well defined tumor border, and non-brain metastasis than those with EGFR mutation. Bubble lucency and higher FDG uptake of lesion and lymph nodes may help distinguish ALK rearrangement from EGFR mutation in the absence of genetic analysis.