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

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 () rearrangement form epidermal growth factor receptor () 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 rearrangement and those with mutation.

RESULTS

Among 145 patients with advanced lung adenocarcinoma, only six patients had both rearrangement and mutation, the sample size was too small to analysis. Univariate analysis revealed that patients with rearrangement were younger (P=0.001) and with lower serum carcinoembryonic antigen (CEA) level (P=0.008) than those with mutation. More of tumors with rearrangement were well defined (P=0.023) and have bubble lucency (P=0.026) compared with those with mutation (P=0.026). Lymphadenopathy was seen more frequently in patients with rearrangement (P=0.167). Twenty-six patients received FDG-PET/CT, among this population, lesion standardized uptake values (SUV) >6.95 and lymph nodes SUV >6.25 were more often seen in 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 rearrangement than mutation. Tumor diameter less than 36 mm were prone to be mutation (RR =0.078, 95% CI: 0.017-0.356, P=0.001).

CONCLUSIONS

Treatment naïve advanced lung adenocarcinomas with 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 mutation. Bubble lucency and higher FDG uptake of lesion and lymph nodes may help distinguish rearrangement from mutation in the absence of genetic analysis.