Epidermal Growth Factor Receptor Mutation Status Confers Survival Benefit in Patients with Non-Small-Cell Lung Cancer Undergoing Surgical Resection of Brain Metastases: A Retrospective Cohort Study

Survival in patients undergoing surgical resection for brain metastasis from lung cancer and utility of different prognostic scales

Brain metastases (BM) from lung cancer are among the most common intracranial tumors. Several studies have published scales to estimate the survival of patients with BM. Routine access to molecular diagnostics and modern oncologic treatments, including targeted therapy and immunotherapy, is limited in low- and middle-income countries (LMICs); therefore, incorporating them into recent prognostic scales may diminish the reliability of the scales in LMICs. This retrospective study aimed to determine the survival of 55 patients who were surgically treated for BM from lung cancer at a Brazilian public tertiary teaching hospital between 2012 and 2022. We determined clinical factors associated with survival, and compared observed survival rates with the estimated survival on prognostic scales. The mean overall survival (OS) was 9.3 months (range:0.2-76.5). At univariate analysis, female sex and improved postoperative Karnofsky performance status (KPS) score were associated with longer survival. The median survival did not differ between groups when classified using the Graded Prognostic Assessment (GPA)-2008, Lung-molecular GPA-2017, and Lung-GPA-2021 scales. According to the Diagnosis-Specific (DS)-GPA-2012 scale, there was a significant difference between the groups. In the multivariate Cox regression survival analysis, a higher DS-GPA-2012 and improved postoperative KPS score remained significantly associated with longer survival. In conclusion, this cohort showed a mean OS of < 1 year. Improved KPS score after surgery was associated with increased survival. This cohort DS-GPA scale demonstrated the highest concordance with observed survival, indicating its potential as a valuable tool for patient stratification in surgical treatment decision-making in LMICs.

Advances in the Molecular Landscape of Lung Cancer Brain Metastasis

Lung cancer is one of the most frequent tumors that metastasize to the brain. Brain metastasis (BM) is common in advanced cases, being the major cause of patient morbidity and mortality. BMs are thought to arise via the seeding of circulating tumor cells into the brain microvasculature. In brain tissue, the interaction with immune cells promotes a microenvironment favorable to the growth of cancer cells. Despite multimodal treatments and advances in systemic therapies, lung cancer patients still have poor prognoses. Therefore, there is an urgent need to identify the molecular drivers of BM and clinically applicable biomarkers in order to improve disease outcomes and patient survival. The goal of this review is to summarize the current state of knowledge on the mechanisms of the metastatic spread of lung cancer to the brain and how the metastatic spread is influenced by the brain microenvironment, and to elucidate the molecular determinants of brain metastasis regarding the role of genomic and transcriptomic changes, including coding and non-coding RNAs. We also present an overview of the current therapeutics and novel treatment strategies for patients diagnosed with BM from NSCLC.

Correlation of EGFR mutation subtypes and survival in surgically treated brain metastasis from non-small-cell lung cancer

OBJECTIVE

Epidermal growth factor receptor (EGFR) mutation is a positive prognostic factor for survival in patients with non-small-cell lung cancer (NSCLC). In such patients, brain metastasis signifies negative outcomes. Patients with NSCLC brain metastasis that may benefit from neurosurgery is under investigation. We aim to investigate the impact of different mutation loci in surgically treated NSCLC brain metastasis patients.

METHODS

This retrospective cohort study included patients with NSCLC brain metastasis who underwent brain lesionectomy, followed by radiotherapy and chemotherapy or targeted therapy. Demographics and tumor characteristics were compared between the EGFR mutant type and wild type groups. Postoperative survival and risk factors were analyzed using log rank and Cox regression methods.

RESULTS

Overall, 101 patients were included, with 57 belonging to the EGFR mutant type group and 44 to the EGFR wild type group. The median postoperative survival was 17 months for the entire cohort, with the duration being 19 and 14 months for EGFR mutant type and wild type patients (p = 0.013), respectively. Multivariate analysis revealed that exon 19 del (p = 0.02) and a high Karnofsky Performance Scale score (p < 0.01) were independent positive prognostic factors to predict survival. The timing of development of the brain metastasis or the location of the intracranial metastasis was not associated with EGFR mutations.

CONCLUSION

EGFR mutations are associated with better survival outcomes in patients with NSCLC brain metastasis suitable for surgical treatment. This advantage was attributed to patients having a specific mutation of exon 19 deletion.

Resection of symptomatic non-small cell lung cancer brain metastasis in the setting of multiple brain metastases

OBJECTIVE

Current guidelines primarily suggest resection of brain metastases (BMs) in patients with limited lesions. With a growing number of highly effective local and systemic treatment options, this view may be challenged. The purpose of this study was to evaluate the role of metastasectomy, disregarding BM count, in a comprehensive treatment setting.

METHODS

In this monocentric retrospective analysis, the authors included patients who underwent resection for at least 1 BM and collected demographic, clinical, and tumor-associated parameters. Prognostic factors for local control and overall survival (OS) were analyzed with the log-rank test and Cox proportional hazards analysis.

RESULTS

The authors analyzed 216 patients. One hundred twenty-nine (59.7%) patients were diagnosed with a single/solitary BM, whereas 64 (29.6%) patients had 2-3 BMs and the remaining 23 (10.6%) had more than 3 BMs. With resection of symptomatic BMs, a significant improvement in Karnofsky Performance Scale (KPS) was achieved (p < 0.001), thereby enabling adjuvant radiotherapy for 199 (92.1%) patients and systemic treatment for 119 (55.1%) patients. During follow-up, 83 (38.4%) patients experienced local recurrence. BM count did not significantly influence local control rates. By the time of analysis, 120 (55.6%) patients had died; the leading cause of death was systemic tumor progression. The mean (range) OS after surgery was 12.7 (0-88) months. In univariate analysis, the BM count did not influence OS (p = 0.844), but age < 65 years (p = 0.007), preoperative and postoperative KPS ≥ 70 (p = 0.002 and p = 0.005, respectively), systemic metastases other than BM (p = 0.004), adjuvant radiation therapy (p < 0.001), and adjuvant systemic treatment (p < 0.001) were prognostic factors. In regression analysis, the presence of extracranial metastases (HR 2.30, 95% CI 1.53-3.48, p < 0.001), adjuvant radiation therapy (HR 0.97, 95% CI 0.23-0.86, p = 0.016), and adjuvant systemic treatment (HR 0.37, 95% CI 0.25-0.55, p < 0.001) remained as independent factors for survival.

CONCLUSIONS

Surgery for symptomatic BM from non-small cell lung cancer may be indicated even for patients with multiple lesions in order to alleviate their neurological symptoms and to consequently facilitate further treatment.

Mutation status and postresection survival of patients with non-small cell lung cancer brain metastasis: implications of biomarker-driven therapy

OBJECTIVE

Non-small cell lung cancer (NSCLC) is the most common primary tumor to develop brain metastasis. Prognostic markers are needed to better determine survival after neurosurgical resection of intracranial disease. Given the importance of mutation subtyping in determining systemic therapy and overall prognosis of NSCLC, the authors examined the prognostic value of mutation status for postresection survival of patients with NSCLC brain metastasis.

METHODS

The authors retrospectively analyzed all cases of NSCLC brain metastasis with available molecular testing data that were resected by a single surgeon at a single academic center from January 2009 to February 2019. Mutation status, demographic characteristics, clinical factors, and treatments were analyzed. Association between predictive variables and overall survival after neurosurgery was determined with Cox regression.

RESULTS

Of the included patients (n = 84), 40% were male, 76% were smokers, the mean ± SD Karnofsky Performance Status was 85 ± 14, and the mean ± SD age at surgery was 63 ± 11 years. In total, 23%, 26%, and 4% of patients had EGFR, KRAS, and ALK/ROS1 alterations, respectively. On multivariate analysis, survival of patients with EGFR (HR 0.495, p = 0.0672) and KRAS (HR 1.380, p = 0.3617) mutations were not significantly different from survival of patients with wild-type (WT) tumor. However, the subgroup of patients with EGFR mutation who also received tyrosine kinase inhibitor (TKI) therapy had significantly prolonged survival (HR 0.421, p = 0.0471). In addition, postoperative stereotactic radiosurgery (HR 0.409, p = 0.0177) and resected tumor diameter < 3 cm (HR 0.431, p = 0.0146) were also significantly associated with prolonged survival, but Graded Prognostic Assessment score ≤ 1.0 (HR 2.269, p = 0.0364) was significantly associated with shortened survival.

CONCLUSIONS

Patients with EGFR mutation who receive TKI therapy may have better survival after resection of brain metastasis than patients with WT tumor. These results may inform counseling and decision-making regarding the appropriateness of resection of NSCLC brain metastasis.