Radiotherapy in combination with systemic therapies for brain metastases: current status and progress

Lymphopenia associated with whole-brain radiotherapy and its effects on clinical outcomes of patients with brain metastases

There is increasing awareness of radiotherapy's potential side effects, such as lymphopenia. Therefore, this study aimed to establish the association between WBRT and the development of lymphopenia in patients with brain metastases undergoing brain radiotherapy (RT), along with evaluating the corresponding clinical outcomes. Including 116 patients with brain metastases undergoing brain radiotherapy, the study collected the absolute lymphocyte counts (ALC) within 2 weeks before brain radiotherapy (pre-radiotherapy, pre-RT), as well as ones at 1 and 2 months after completing RT (post-RT). Univariate and multivariate analyses were performed to identify associations between radiation modality and post-RT ALC. The relationships between post-RT ALC and overall survival were evaluated with Kaplan-Meier analysis and a multivariate Cox regression model. The median ALC definitely decreased at 1 month post-RT, but at 2 months post-RT, gradually rose but not to the pre-RT ALC. The multivariate analysis identified WBRT and lower pre-RT ALC as independent risk factors associated with the decrease in post-RT ALC at 1 month. It also revealed more than 4 brain metastases, G3-4 lymphopenia at 1 month and lower post-RT ALC at 2 months exhibited significantly worse prognosis regardless of the radiation modality. However, there was indeed an independent correlation between radiation modality and the outcome of intracranial progression-free survival (PFS). To approach the feasibility and reasonableness of treatment, clinicians should carefully consider various factors to achieve long-term survival of patients.

G-CSF improving combined whole brain radiotherapy and immunotherapy prognosis of non-small cell lung cancer brain metastases

OBJECTIVE

To evaluate the therapeutic advantage of G-CSF to whole brain radiotherapy (WBRT) in combination with immunotherapy as a first-line treatment for non-small cell lung cancer (NSCLC) brain metastases (BMs).

METHODS

In this retrospective study, 117 patients (37 in G-CSF group and 80 in no G-CSF group) who underwent first-line WBRT combined with immunotherapy were enrolled. Their survival, intracranial response, BM-related symptoms and toxicity were evaluated.

RESULTS

The overall survival (OS) of patients in G-CSF group was significantly improved compared to patients no G-CSF group (median time: 14.8 vs 10.2 months; HR: 0.61, 95 % CI: 0.38-0.97, p = 0.035). However, there were no significant differences in intracranial responses between the two groups (p > 0.05). The G-CSF group exhibited a significantly higher rate of relief from BM-related symptoms compared to the no G-CSF group (91.7 % vs 59.5 %, p = 0.037). Cox proportional hazards regression analyses indicated that after-treatment ALC > 0.9 × 10^9/L (HR 0.57, 95 % CI 0.32-0.99, p = 0.046) and Hb > 110 g/dL (HR 0.41, 95 % CI 0.24-0.71, p = 0.001) were significant potential factors associated with extended OS. The addition of G-CSF was well tolerated and effectively reduced the incidence of neutropenia (0 % vs 5.0 %, p = 0.17).

CONCLUSION

Integrating G-CSF with WBRT and immunotherapy as a first-line treatment for NSCLC-BMs has exhibited significant efficacy and favorable tolerability.

Pyrotinib combining with radiotherapy on breast cancer with brain metastasis

With the extensive application of anti-human epidermal growth factor receptor-2 (HER2) targeted therapy, the prognosis of HER2-positive breast cancer brain metastasis (BCBM) has been improved greatly. Due to the lack of prospective randomized controlled studies; however, the treatment of active brain metastasis (BM) remains a difficulty in clinic. Based upon the retrospective studies, an effective approach of radiotherapy combined with pyrotinib in HER2-positive BCBM treatment was investigated in present research. In all, 29 patients who had active BM in HER2-positive breast cancer (BC) and underwent whole-brain radiotherapy (WBRT) combined with pyrotinib from January 2019 to May 2021 were enrolled. The progression-free survival (PFS), overall survival (OS), clinical benefit rate (CBR), objective response rate (ORR), and drug-related adverse events (AEs) were analyzed among patients undergoing WBRT combined with concurrent or sequence pyrotinib + capecitabine. After the systematic treatments using WBRT combined with pyrotinib + capecitabine, the mPFS and mOS of BM patients were 6.5 months and 15.5 months, respectively. PFS (7.2 vs 6.2 months, p = 0.038) and OS (19.0 vs 14.0 months, p = 0.014) were longer after sequence treatments than those after concurrent treatment. The central nervous system (CNS) ORR of sequence treatment was superior to that of concurrent treatment (80.4% vs 58.6%, p < 0.05). Vomiting (17.2%) and diarrhea (10.3%) were the most common adverse reactions ⩾ grade 3. WBRT combined with pyrotinib is safe and effective for the treatments of active BM in HER2-positive BC. WBRT combined with sequence pyrotinib + capecitabine is more effective and less toxic than concurrent treatment. Therefore, sequence treatment is potentially a preferred regimen for patients with active BM in HER2-positive BC. The size and number of BM lesions, presence or absence of hepatic metastasis, and combination mode of radiotherapy and targeted therapy are independent risk factors for active BM prognosis.

Breast Cancer Subtypes and Mortality of Breast Cancer Patients With Brain Metastasis at Diagnosis: A Population-Based Study

Background

Brain metastasis is an important cause of breast cancer-related death.

Aim

We evaluated the relationships between breast cancer subtype and prognosis among patients with brain metastasis at the initial diagnosis.

Methods

The Surveillance, Epidemiology, and End Results database was searched to identify patients with brain metastasis from breast cancer between 2010 and 2015. Multivariable Cox proportional hazard models were used to identify factors that were associated with survival among patients with initial brain metastases. The Kaplan–Meier method was used to compare survival outcomes according to breast cancer subtype.

Results

Among 752 breast cancer patients with brain metastasis at diagnosis, 140 patients (18.6%) underwent primary surgery and 612 patients (81.4%) did not undergo surgery, while 460 patients (61.2%) received chemotherapy and 292 patients (38.8%) did not receive chemotherapy. Multivariable analysis revealed that, relative to HR+/HER2– breast cancer, HR–/HER2– breast cancer was associated with significantly poorer overall survival (hazard ratio: 2.52, 95% confidence interval: 1.99–3.21), independent of age, sex, race, marital status, insurance status, grade, liver involvement, lung involvement, primary surgery, radiotherapy, and chemotherapy. The median overall survival intervals were 12 months for HR+/HER2−, 19 months for HR+/HER2+, 11 months for HR−/HER2+, and 6 months for HR–/HER2– (P < .0001). Relative to HR+/HER2– breast cancer, HR–/HER2– breast cancer was associated with a significantly higher risk of mortality among patients, and the association was stronger among patients who received chemotherapy (p for interaction = .005).

Conclusions

Breast cancer subtype significantly predicted overall survival among patients with brain metastasis at diagnosis.

Integration of Systemic Therapy and Stereotactic Radiosurgery for Brain Metastases

Simple Summary

In the multi-modal treatment of brain metastasis (BM), the role of systemic therapy has undergone a recent revolution. Due to the development of multiple agents with modest central nervous system penetration of the blood-brain barrier, targeted therapies and immune checkpoint inhibitors are increasingly being utilized alone or in combination with radiation therapy. However, the adoption of sequential or concurrent strategies varies considerably, and treatment strategies employed in clinical practice have rapidly outpaced evidence development. Therefore, this review critically analyzes the data regarding combinatorial approaches for a variety of systemic therapeutics with stereotactic radiosurgery and provides an overview of ongoing clinical trials.

Abstract

Brain metastasis (BM) represents a common complication of cancer, and in the modern era requires multi-modal management approaches and multi-disciplinary care. Traditionally, due to the limited efficacy of cytotoxic chemotherapy, treatment strategies are focused on local treatments alone, such as whole-brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), and resection. However, the increased availability of molecular-based therapies with central nervous system (CNS) penetration now permits the individualized selection of tailored systemic therapies to be used alongside local treatments. Moreover, the introduction of immune checkpoint inhibitors (ICIs), with demonstrated CNS activity has further revolutionized the management of BM patients. The rapid introduction of these cancer therapeutics into clinical practice, however, has led to a significant dearth in the published literature about the optimal timing, sequencing, and combination of these systemic therapies along with SRS. This manuscript reviews the impact of tumor biology and molecular profiles on the management paradigm for BM patients and critically analyzes the current landscape of SRS, with a specific focus on integration with systemic therapy. We also discuss emerging treatment strategies combining SRS and ICIs, the impact of timing and the sequencing of these therapies around SRS, the effect of corticosteroids, and review post-treatment imaging findings, including pseudo-progression and radiation necrosis.