Recursive Partitioning Analysis of Systemic Therapy after Radiotherapy in Patients with Brain Metastases

Brain Metastases: Is There Still a Role for Whole-Brain Radiation Therapy?

Whole-brain radiation therapy (WBRT) has commonly been prescribed to palliate symptoms from brain metastases, to reduce the risk of local relapse after surgical resection, and to improve distant brain control after resection or radiosurgery. While targeting micrometastases throughout the brain can be considered advantageous, the simultaneous exposure of healthy brain tissue might cause adverse events. Attempts to mitigate the risk of neurocognitive decline after WBRT include the selective avoidance of the hippocampi, among others. Besides selective dose reduction, dose escalation to boost volumes, for example, simultaneous integrated boost, aiming at increased tumor control probability is technically feasible. While up-front radiotherapy for newly diagnosed brain metastases often employs radiosurgery or other techniques targeting visible lesions only, sequential (delayed) salvage treatment with WBRT might still become necessary. In addition, the presence of leptomeningeal tumors or very widespread parenchymatous brain metastases might prompt clinicians to prescribe early WBRT.

Primary systemic therapy for patients with brain metastases from lung cancer ineligible for targeted agents

Purpose

The purpose of this study was to evaluate overall survival after systemic therapy, largely chemotherapy, in patients with small cell or non-small cell lung cancer and brain metastases. After completion of systemic therapy, some patients received planned brain irradiation, while others were followed.

Methods

Retrospective cohort study.

Results

Thirty-eight patients were included (28 small cell, 20 followed with imaging). Six of these 20 patients (30%) received delayed radiotherapy during follow-up. Planned radiotherapy (n = 18, intention-to-treat) was associated with longer survival from diagnosis of brain metastases, median 10.8 versus 6.1 months, p = 0.025. Delayed radiotherapy still resulted in numerically better survival than no radiotherapy at all (median 8.8 versus 5.3 months, not significant). If calculated from the start of delayed radiotherapy, median survival was only 2.7 months. In a multivariable analysis, both Karnofsky performance status ≥ 70 (p = 0.03) and planned radiotherapy (p = 0.05) were associated with better survival.

Conclusion

In patients ineligible for targeted agents, planned radiotherapy in a modern treatment setting was associated with longer survival compared to no radiotherapy. Timing and type of radiotherapy in such patients should be evaluated in prospective trials to identify patients who might not need planned radiotherapy.

A Case of Five-Year Survival After Combined-Modality Treatment for Non-Small Cell Lung Cancer With Intraspinal Metastasis

This case report describes the treatment approach and outcome in a 69-year-old female patient with non-small cell lung cancer (NSCLC) diagnosed with T4 N2 M1b (intraspinal) disease. The two most common targets for tyrosine kinase inhibitors (epidermal growth factor receptor and anaplastic lymphoma kinase) were not expressed. Programmed death-ligand 1 (PD-L1) was expressed in <50% of the tumor cells. In 2016, initial guideline-concordant treatment with carboplatin/vinorelbine chemotherapy was initiated. Between the first two cycles, all positron emission tomography (PET) positive lesions were irradiated with 30 Gy in 10 fractions (lung, nodes, thoracic spinal manifestation). After nine months with excellent response (at least partial remission, possibly fibrosis only), bilateral lung metastases were diagnosed. The patient was started on nivolumab monotherapy (later atezolizumab due to a change in National practice) and completed two years of treatment. She is currently in continued complete remission with regular follow-up examinations. This case illustrates that outcomes comparable to those observed in patients with limited brain metastases may be observed in patients with localized intraspinal disease and that immune checkpoint inhibitors play an important role in the management of metastatic NSCLC.