Gamma knife stereotactic radiosurgery for the management of incidentally-identified brain metastasis from non-small cell lung cancer

Comparison of Surgical Resection and Stereotactic Radiosurgery in the Initial Treatment of Brain Metastasis

BACKGROUND

Brain metastasis (BM) is the most common brain malignancy and a common cause of death in cancer patients. However, the relative outcome-related advantages and disadvantages of surgical resection (SR) and stereotactic radiosurgery (SRS) in the initial treatment of BM are controversial.

METHOD

We systematically reviewed the English language literature up to March 2020 to compare the efficacy of SR and SRS in the initial treatment of BM. We identified cohort studies from the Cochrane Library, PubMed, and EMBASE databases and conducted a meta-analysis following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Twenty cohort studies involving 1,809 patients were included. Local control did not significantly differ between the SR and SRS groups overall (hazard ratio [HR] 1.02, 95% confidence interval (CI) 0.64-1.64, p = 0.92; I2 = 54%, p = 0.03) or in subgroup analyses of SR plus SRS vs. SRS alone, SR plus whole brain radiation therapy (WBRT) versus SRS plus WBRT, or SR plus WBRT versus SRS alone. Distant intracranial control did not significantly differ between the SR and SRS groups overall (HR 0.78, 95% CI 0.38-1.60, p = 0.49; I2 = 61%, p = 0.03) or in subgroup analyses of SR plus SRS versus SRS alone or SR plus WBRT versus SRS alone. In addition, overall survival (OS) did not significantly differ in the SR and SRS groups (HR 0.91, 95% CI 0.65-1.27, p = 0.57; I2 = 47%, p = 0.09) or in subgroup analyses of SR plus SRS versus SRS alone, SR plus WBRT versus SRS alone or SR plus WBRT versus SRS plus WBRT.

CONCLUSION

Initial treatment of BM with SRS may offer comparable local and distant intracranial control to SR in patients with single or solitary BM. OS did not significantly differ between the SR and SRS groups in people with single or solitary BM.

Impact of Tyrosine Kinase Inhibitors (TKIs) Combined With Radiation Therapy for the Management of Brain Metastases From Renal Cell Carcinoma

Background: Targeted therapy has transformed the outcome for patients with metastatic renal cell carcinoma. Their efficacy and safety have also been demonstrated in brain metastatic RCC. Preclinical evidence suggests synergism of radiation and tyrosine kinase inhibitors. Consequently, several studies have compared their efficacy in the treatment of RCC brain metastases to the era of brain management with surgery/radiation only.

Objectives: We seek to systematically review and meta-analyze the results of those studies that involved comparative intervention groups of brain management; TKIs, and never used TKIs.

Methods and Materials: Online databases (PubMed, EMBASE, Cochrane library, and ClinicalTrials.gov) were searched for comparative studies. Overall survival as the primary outcome of interest, and local brain control, distant control, and adverse events as secondary outcomes of interest were recorded for meta-analysis. Hazard ratios were pooled together using Review Manager 5.3. Fixed effects or random effects model were adopted according to the level of heterogeneity. Subgroup analysis included studies that involved SRS as the local treatment of management.

Results: Overall 7 studies (n = 897) were included for meta-analysis. TKI use was associated with better survival (HR 0.60 [0.52, 0.69], p < 0.00001) and local brain control (HR 0.34 [0.11, 0.98], p = 0.05). SRS subgroup also revealed significantly better survival (HR 0.61 [0.44, 0.83], p = 0.002) and local brain control (HR 0.19 [0.08, 0.45], p = 0.0002). Distant brain control (HR 0.95 [0.67, 1.35], p = 0.79) and brain progression free survival were unaffected (HR 0.94 [0.56, 1.56], p = 0.80). Only one study (n = 376) reported significantly greater 12-months cumulative incidence of radiation necrosis with TKI use within 30 days of SRS (10.9 vs. 6.4%, p = 0.04).

Conclusions: TKIs use in combination with SRS is safe and effective for treating RCC brain metastases. Larger randomized controlled trials are warranted to validate the results.

Tumor Primary Site and Histology Subtypes Role in Radiotherapeutic Management of Brain Metastases

Randomized controlled trials have failed to report any survival advantage for WBRT combined with SRS in the management of brain metastases, despite the enhanced local and distant control in comparison to each treatment alone. Literature review have revealed important role of primary histology of the tumor when dealing with brain metastases. NSCLC responds better to combined approach even when there was only single brain metastasis present while breast cancer has registered better survival with SRS alone probably due to better response of primary tumor to advancement in surgical and chemotherapeutic agents. Furthermore, mutation status (EGFR/ALK) in lung cancer and receptor status (ER/PR/HER2) in breast cancer also exhibit diversity in their response to radiotherapy. Radioresistant tumors like renal cell carcinoma and melanoma brain metastases have achieved better results when treated with SRS alone. Secondly, single brain metastasis may benefit from local and distant brain control achieved with combined treatment. These diverse outcomes suggest a primary histology-based analysis of the radiotherapy regimens (WBRT, SRS, or their combination) would more ideally establish the role of radiotherapy in the management of brain metastases. Molecularly targeted therapeutic and immunotherapeutic agents have revealed synergism with radiation therapy particularly SRS in treating cancer patients with brain metastases. Clinical updates in this regard have also been reviewed.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Role of Surgery in the Management of Adults With Metastatic Brain Tumors

Please see the full-text version of this guideline https://www.cns.org/guidelines/guidelines-treatment-adults-metastatic-brain-tumors/chapter_2) for the target population of each recommendation listed below.  SURGERY FOR METASTATIC BRAIN TUMORS AT NEW DIAGNOSIS QUESTION: Should patients with newly diagnosed metastatic brain tumors undergo surgery, stereotactic radiosurgery (SRS), or whole brain radiotherapy (WBRT)?

RECOMMENDATIONS

Level 1: Surgery + WBRT is recommended as first-line treatment in patients with single brain metastases with favorable performance status and limited extracranial disease to extend overall survival, median survival, and local control. Level 3: Surgery plus SRS is recommended to provide survival benefit in patients with metastatic brain tumors Level 3: Multimodal treatments including either surgery + WBRT + SRS boost or surgery + WBRT are recommended as alternatives to WBRT + SRS in terms of providing overall survival and local control benefits.  SURGERY AND RADIATION FOR METASTATIC BRAIN TUMORS QUESTION: Should patients with newly diagnosed metastatic brain tumors undergo surgical resection followed by WBRT, SRS, or another combination of these modalities?

RECOMMENDATIONS

Level 1: Surgery + WBRT is recommended as superior treatment to WBRT alone in patients with single brain metastases. Level 3: Surgery + SRS is recommended as an alternative to treatment with SRS alone to benefit overall survival. Level 3: It is recommended that SRS alone be considered equivalent to surgery + WBRT.  SURGERY FOR RECURRENT METASTATIC BRAIN TUMORS QUESTION: Should patients with recurrent metastatic brain tumors undergo surgical resection?

RECOMMENDATIONS

Level 3: Craniotomy is recommended as a treatment for intracranial recurrence after initial surgery or SRS.  SURGICAL TECHNIQUE AND RECURRENCE QUESTION A: Does the surgical technique (en bloc resection or piecemeal resection) affect recurrence?

RECOMMENDATION

Level 3: En bloc tumor resection, as opposed to piecemeal resection, is recommended to decrease the risk of postoperative leptomeningeal disease when resecting single brain metastases.

QUESTION B

Does the extent of surgical resection (gross total resection or subtotal resection) affect recurrence?

RECOMMENDATION

Level 3: Gross total resection is recommended over subtotal resection in recursive partitioning analysis class I patients to improve overall survival and prolong time to recurrence. The full guideline can be found at https://www.cns.org/guidelines/guidelines-treatment-adults-metastatic-brain-tumors/chapter_2.

Methods and results of locoregional treatment of brain metastases in patients with non-small cell lung cancer

This article presents methods and results of surgery and radiotherapy of brain metastases from non-small cell lung cancer (BMF-NSCLC). Patients with single BMF-NSCLC, with Karnofsky score ≥ 70 and controlled extracranial disease are the best candidates for surgery. Stereotactic radiosurgery (SRS) is recommended in patients with 1-3 BMF-NSCLC below 3-3.5 cm, with minor neurological symptoms, located in parts of the brain not accessible to surgery, with controlled extracranial disease. Whole brain radiotherapy (WBRT) following SRS reduces the risk of local relapse; in selected patients median survival reaches more than 10 months. Whole brain radiotherapy alone is a treatment in patients with multiple metastases, poor performance status, uncontrolled extracranial disease, disqualified from surgery or SRS with median survival 3 to 6 months. There is no doubt that there are patients with BMF-NSCLC who should receive only the best supportive care. There is a debate in the literature on how to select these patients.

Comparison Between Surgical Resection and Stereotactic Radiosurgery in Patients with a Single Brain Metastasis from Non-Small Cell Lung Cancer

BACKGROUND

The management of patients with single brain metastasis (BM) from non-small cell lung cancer (NSCLC) is controversial. Surgical resection (SR) with adjuvant irradiation and stereotactic radiosurgery (SRS) are performed in the treatment of such lesions. This study compared both modalities in terms of tumor control and survival.

METHODS

During the period 2004-2011, 115 patients with single BM from NSCLC were treated with SR or SRS at our institution. Median patient age was 61 years. SR was performed in 43 patients, and SRS was performed in 72 patients. Most patients who underwent SR had adjuvant irradiation. Of patients, 63% in the SR group and 56% in the SRS group had synchronous presentation of BM and lung primary tumor. Thoracic disease was managed with curative intent in 60% of patients in the SR group compared with 50% of patients in the SRS group.

RESULTS

Median follow-up was 10.2 months. Local control was 72% in patients in the SR group and 79% in patients in the SRS group (P = 0.992). Median survival for patients in the SR group was 13.3 months, and median survival for patients in the SRS group was 7.8 months (P = 0.047). Multivariate analyses revealed aggressive treatment of the primary NSCLC as an independent factor associated with prolonged survival in patients undergoing SR. In the SRS group, patients with metachronous metastasis showed a better prognosis. Metachronous presentation was associated with more aggressive management of the primary tumor.

CONCLUSIONS

In this study, patients with single BM undergoing SR had a survival advantage. However, because SR and SRS achieved comparable local control of BM, patients receiving SRS should benefit from an equally aggressive treatment of the primary NSCLC, as thoracic management was the most important predictor of survival.

[Advances in diagnosis and treatment of brain metastases from the primary lung cancer]

肺癌脑转移的发生率为23%-65%，是脑转移性肿瘤中最常见的类型，且预后较差。目前肺癌脑转移的诊治和分子机理已成为众多研究的热点之一。本文就肺癌脑转移的临床特征、诊断和治疗方面的进展以及最新脑转移的机制学研究做了系统的综述。