Effects of EGFR gene mutation on stage 3A lung adenocarcinomas in the clinical decision-making process for mediastinal invasive staging

Objective: In our study, we aimed to evaluate the effects of EGFR gene mutation on the clinical course of Non-Small Cell Lung carcinoma. Material and Methods: Our study was conducted retrospectively on patients who were operated on for NSCLC diagnosed as adenocarcinoma. The International Cancer Control Association and the American Cancer Committee eighth TNM classification system were evaluated in our study. Case groups at this stage were divided into two main groups as EGFR gene mutation (+/-) and data between the clinical behaviours of these two main groups were investigated. Results: There was no statistically significant difference between the two groups in terms of age, gender, smoking, and type of surgery (p = 0.727, p = 0.936, p = 0.463). The relationship between EGFR and surgery type was also not significant (2 = 0.268; p = 0.992). There were no statistically significant difference between the medians of Suv-Max value (z = 1.083; p = 0.279). Among 653 cases in all NSCLC adenocarcinoma subtypes, EGFR gene mutation positivity was 23.89%. When we evaluate the progression of patients with EGFR gene mutation from stage 3A to 3B, it is more aggressive in cases with EGFR gene mutation, but it is not statistically significant (c2=2.924; p=0.087). Conclusions: Knowledge of whether there is an EGFR gene mutation can provide important clinical information. In this respect, EGFR gene mutation positivity in stage 3A cases may constitute an indication for preoperative invasive mediastinal sampling, but we need more data to get statistically definitive results.