Distribution of EGFR and KRAS Mutations in Patients with Surgically Resected Non-Small Cell Lung Cancer from Southern Italy: Real-Life Data from a Single Institution and Literature Review

Background/objectives: The identification of driver mutations in NSCLC such as those in the EGFR and KRAS genes has revolutionized the understanding and management of many lung cancer patients and has opened up a new scenario in the early disease stages in terms of therapeutic options (EGFR) and prognosis (KRAS). Data on prevalence rates and disease stage distributions of EGFR and KRAS mutations in surgically resected NSCLC are growing, but in Southern Italy, estimation is limited, since upfront EGFR testing in early-stage adenocarcinoma has been only recently introduced according to the current guidelines in clinical practice, whereas KRAS screening is usually uninvestigated in resected NSCLC. In this real-life study of a single institution in the Apulia Region, we provide an overview of the epidemiological distribution of EGFR and KRAS mutations in patients in Southern Italy with resected NSCLC, highlighting their prevalence, clinical significance, and correlation with demographic and pathological factors. A literature review was also performed to compare our findings with the most recent available data from the screening of Italian cohorts of advanced and surgically resected NSCLC patients. Methods: Data from 149 patients coming from Southern Italy with surgically resected NSCLC were retrospectively collected over a period of 16 years. EGFR and KRAS mutation screenings were performed and correlated with clinical and pathological data. Results: In total, 24 out of 149 NSCLC (16%) patients harbored an EGFR mutation. Exon 19 deletions and missense p.L858R mutations of the EGFR gene have quite similar frequencies (46%) and were more observed in never smokers (p < 0.001) and female (p < 0.001) patients with the adenocarcinoma histotype. KRAS gene mutations were detected in 31.5% of cases, with missense p.G12C (32%), p.G12V (28%), and p.G12D (17%) mutations as the most frequent ones. Neither EGFR nor KRAS mutational status were found to impact overall survival (OS) in our study cohort. Conclusions: Our findings improve the understanding of lung cancer genetics in a small and homogeneous area of Southern Italy and guide future research. The EGFR and KRAS mutations in NSCLC resected patients from Southern Italy showed a global similar incidence compared to other recently described Italian cohorts of advanced and early-stage NSCLC, with a higher frequency of exon19 EGFR deletions. No prognostic impact was observed for both EGFR and KRAS status, but additional investigations on a larger cohort are needed.