Icotinib combined whole brain radiotherapy for patients with brain metastasis from lung adenocarcinoma harboring epidermal growth factor receptor mutation

A meta-analysis for the efficacy and safety of icotinib combined with radiotherapy in treating brain metastases of non-small cell lung cancer

BACKGROUND

Currently, the therapies for brain metastases of non-small cell lung cancer (NSCLC) mainly include whole brain radiotherapy and icotinib. For exploring the efficacy and safety of radiotherapy and icotinib, a meta-analysis was performed based on a series of data.

METHOD

A systematic search was performed on PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure and Wanfang Database. The search time was set from the database establishment to December, 2022. All randomized controlled trials evaluating the efficacy and safety of whole brain radiotherapy alone or in combination with icotinib for whole brain metastases of NSCLC were included in our meta-analysis. Clinical outcomes and adverse reactions were analyzed using Stata17.0 software.

RESULTS

Finally, 10 clinical studies were enrolled in this meta-analysis, including 717 patients. Briefly, compared with radiotherapy alone, icotinib combined with radiotherapy increased response rate [relative ratio (RR) = 1.240; 95% confidence interval (CI) (1.141, 1.348); P < .001] and disease control rate (RR = 1.240, 95% CI [1.141,1.348], P < .001). Besides, according to the outcomes of adverse reaction assessment exhibited, there were no significant differences between the 2 group patients in the incidence of rash (RR = 1.536, 95% CI [0.694, 3.402], P = .290), adverse reaction in gastrointestinal tract (RR = 1.060, 95% CI [0.792, 1.419], P = 1.419), hepatic injury (RR = 1.541, 95% CI [0.798,2.975], P = .198) and leukopenia (RR = 1.182, 95% CI [0.787, 1.777], P = .421). However, the patients receiving combination treatment showed much longer progression free survival than those receiving radiotherapy alone (standardized mean difference = 1.559; 95% CI [0.699, 2.419]; P < .001).

CONCLUSION

Icotinib combined with radiotherapy can significantly short-term and long-term efficacy of NSCLC patients with brain metastases but not increase adverse reactions.

The Presence of Genomic Instability in Cerebrospinal Fluid in Patients with Meningeal Metastasis

Purpose

This study aimed to explore the genomic instability in cerebrospinal fluid (CSF) in patients with meningeal metastasis (MM).

Material and Methods

We collected the blood and CSF samples of 15 MM patients and one brain parenchymal metastasis (BPM) patient. A panel of 543 cancer-related genes was conducted to analyze the status of genomic instability in CSF and plasma cell-free DNA (cfDNA) of all patients. Subsequently, nine patients underwent low-depth whole-genome sequencing (WGS) analysis to verify the existence of genomic instability, followed by genomic scoring by the application of aneuploidy scores. Diagnosis-specific graded prognostic assessment (DS-GPA) score was utilized to assess the clinical status of MM patients.

Results

There was significant difference in gene mutation between CSF cfDNA and plasma cfDNA in MM patients. Among them, 12 MM patients developed genomic instability in their CSF cfDNA, while the remaining 3 had stable genetic profile. Besides, BPM patients showed genomic stability in his CSF and paraffin-embedded tissue sections. No genomic instability was noticed in plasma cfDNA of all patients. Sensitive mutations on EGFR, ERBB2, ALK and KRAS genes and increased gene copy numbers of MET and ERBB2 were detected in 10 MM patients with genomic instability, as well as the EGFR gene mutation in one MM case with genomic stability. Additionally, MM patients with genomic instability had lower overall survival and higher aneuploidy scores and tumor mutation burden compared with those with genomic stability. Moreover, MM patients with higher DS-GPA scores benefited from better survival.

Conclusion

Genomic instability existed in the CSF cfDNA rather than plasma cfDNA of MM patients, which might be the underlying cause of the differences in MM.

Icotinib: efficacy in different solid tumors and gene mutations

Icotinib is a first-generation inhibitor of epidermal growth factor receptor, which has been approved by the Chinese National Medical Products Administration, for the treatment of non-small cell lung cancer with epidermal growth factor receptor sensitive mutations. In addition, icotinib also shows moderate activity in other solid tumors driven by epidermal growth factor receptor, including non-small cell lung cancer with epidermal growth factor receptor rare non-resistant mutations, and esophageal cancer with epidermal growth factor receptor amplification or overexpression. This article reviews the efficacy of icotinib in different solid tumors with different epidermal growth factor receptor alterations.

Pulsatile Erlotinib in EGFR-Positive Non-Small-Cell Lung Cancer Patients With Leptomeningeal and Brain Metastases: Review of the Literature

Patients with epidermal growth factor receptor (EGFR)-positive (EGFR⁺) non-small-cell lung cancer (NSCLC) show improved response rates when treated with tyrosine kinase inhibitors (TKIs) such as erlotinib. However, standard daily dosing of erlotinib often does not reach therapeutic concentrations within the cerebrospinal fluid (CSF), resulting in progression of central nervous system (CNS) disease. Intermittent, high-dose administration of erlotinib reaches therapeutic concentrations within the CSF and is well tolerated in patients. Experience with "pulsatile" dosing, however, is limited. We review the literature on the pharmacology and clinical outcomes of pulsatile erlotinib in the treatment of EGFR⁺ NSCLC with brain and leptomeningeal metastases, and include available data on the use of next-generation TKIs in CNS progression. We also provide our institution's experience with patients treated with pulsatile erlotinib for CNS metastasis, and propose clinical criteria for its use. Pulsatile erlotinib is a reasonable alternative in EGFR⁺ patients with new or worsening CNS disease, without evidence of systemic progression, and without confirmed T790M resistance mutations within the CNS.