<i>EGFR</i> Mutation–Positive Unresectable Stage III Non-Squamous Lung Cancer Is Associated with a High Incidence of Brain Metastasis

Kim, Hongsik; Park, Sehhoon; Jung, Hyun Ae; Sun, Jong-Mu; Lee, Se-Hoon; Ahn, Jin Seok; Ahn, Myung-Ju

doi:.0.0.0

Cancer Research and Treatment > Epub ahead of print

Original Article

doi: https://doi.org/10.4143/crt.2022.388 [Epub ahead of print]

EGFR Mutation–Positive Unresectable Stage III Non-Squamous Lung Cancer Is Associated with a High Incidence of Brain Metastasis

Hongsik Kim¹

, Sehhoon Park², Hyun Ae Jung², Jong-Mu Sun², Se-Hoon Lee², Jin Seok Ahn², Myung-Ju Ahn²

¹Division of Hematology-Oncology, Department of Internal Medicine, Chungbuk National University Hospital, Cheongju, Korea
²Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea

Correspondence

Myung-Ju Ahn ,Tel: 82-2-3410-3459, Fax: 82-2-3410-1754, Email: silkahn@skku.edu

Received: June 16, 2022; Accepted: September 30, 2022. Published online: October 4, 2022.

ABSTRACT

Purpose
The impact of epidermal growth factor receptor (EGFR) mutation in locally advanced non–small cell lung cancer (NSCLC) remains controversial. This study was conducted to investigate the clinical outcomes and recurrence patterns after definitive chemoradiotherapy (CRT) in patients with unresectable stage III non-squamous-cell lung cancer according to EGFR mutation status.
Materials and Methods
We retrospectively reviewed 604 patients with pathologically confirmed stage III NSCLC who were treated with definitive CRT and were examined for EGFR mutation at Samsung Medical Center, Korea, from January 2013 to December 2018. Among them, we identified 236 patients with stage III non-squamous-cell lung cancer who were treated with definitive CRT and were examined for EGFR mutation status. We analyzed the frequency of EGFR mutation, progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and recurrence pattern.
Results
Among 236 patients, EGFR mutation was detected in 71 patients (30.1%) and the median follow-up duration was 41.7 months. There were no significant differences in PFS (9.9 vs. 10.9 months, p=0.236), and ORR to CRT (93.0% vs. 90.3%, p=0.623) according to EGFR mutation status. However, the EGFR mutant group showed significantly higher recurrence (88.7% vs. 75.2%, p=0.022), distant metastasis (76.1% vs. 61.2%, p=0.036) rates, especially brain (38.0% vs. 12.7%, p < 0.001), and better median OS (59.2 vs. 41.3 months, p=0.037) compared with patients without EGFR mutation.
Conclusion
Patients with EGFR mutation–positive unresectable stage III non-squamous lung cancer exhibited higher recurrence and distant metastasis rates, especially brain metastasis.

Key words: Non-small-cell lung carcinoma, EGFR mutation, Chemoradiotherapy, Metastasis, Survival