Osimertinib for EGFR‐Mutant Lung Cancer with Brain Metastases: Results from a Single‐Center Retrospective Study. (20th August 2018)

• Record Type: Journal Article
• Authors: Xie, Lijia; Nagpal, Seema; Wakelee, Heather A.; Li, Gordon; Soltys, Scott G.; Neal, Joel W.
• Is Part Of: Oncologist. Volume 24:Number 6(2019)
• Page Start: 836
• Page End: 843
• Publication Date: 2018-08-20
• Subjects: Osimertinib -- Brain metastases -- EGFR‐mutant lung cancer -- Stereotactic radiosurgery; Oncology -- Periodicals; Tumors -- Periodicals; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Oncology; Tumors; Neoplasms; Electronic journals; Periodicals; Periodicals; 616.994
• DOI: 10.1634/theoncologist.2018-0264
• Languages: English
• ISSNs: 1083-7159

Abstract

Abstract: Introduction: Osimertinib is a third‐generation tyrosine kinase inhibitor, initially approved for epidermal growth factor receptor (EGFR) mutant non‐small cell lung cancer (NSCLC) with T790M acquired resistance, and now approved in the first‐line setting. However, data supporting the use of osimertinib in untreated brain metastases are limited, although it has established central nervous system (CNS) activity. Our study compares the clinical outcomes of patients experiencing progressing brain metastases treated with cranial irradiation and osimertinib with those treated with osimertinib alone. Methods: Forty patients who were treated with osimertinib at the Stanford Cancer Center from November 2015 to December 2016 were identified by searching an electronic medical record database. Eleven patients had progressing brain metastases and did not receive radiation (group A), 9 patients had progressing brain metastases and received radiation when starting osimertinib (group B), and 20 patients had stable brain metastases at the time of initiating osimertinib (group C). Patient and disease characteristics, radiographic responses, and survival outcomes were evaluated retrospectively for the three groups. Results: The CNS response rate was 32.3%. Median time to treatment failure (TTF), overall progression‐free survival (PFS), and overall survival (OS) were 10.0 months (95% confidence interval [CI], 4.5–11.8), 8.8 months (95% CI, 6.2–12.1), and 16.2 months, respectively. Median TTF was 15.1 months for group A (95% CI, 1.7–28.5), 7.7 months for group B (95% CI, 0–15.5), and 10.7 months for group C (95% CI, 9.0–12.5). The median PFS was 8.8 months for group A (95% CI, 4.3–13.4), not reached for group B, and 8.4 months for group C (95% CI, 5.6–11.1). The median OS was not reached for group A and C, and was 16.2 months for group B. There was no apparent difference in TTF, PFS, or OS between the three groups. Conclusion: Receiving radiation prior to starting osimertinib for patients with progressing brain metastases did not prolong TTF, PFS, or OS in our series. To minimize the risks of radiation‐related toxicity, delaying radiation could be considered for some patients with EGFR ‐mutant NSCLC with brain metastases who initially respond to osimertinib in the second‐line setting. Abstract : A single‐center retrospective study of 40 patients with epidermal growth factor receptor mutant lung cancer with brain metastases treated with osimertinib was conducted, with a focus on whether patients who initially responded to osimertinib may be able to defer or delay radiation without reducing overall survival.