Radiosurgery for small-cell lung cancer brain metastases: a review

External Validation of an Extended Prognostic Assessment Model in Patients With Brain Metastases from Small-cell Lung Cancer

Background/Aim

Recently, the small-cell lung cancer (SCLC) grade model for patients with brain metastases was developed by a Japanese group. It includes sex, performance status, number of brain metastases, primary tumor control and presence of extracranial metastases. The aim of the present study was to validate this prognostic score in a European cohort of patients.

Patients and Methods

The retrospective validation study included 189 patients from two centers in Germany and Norway. Survival according to the SCLC grade score was evaluated. Additional prognostic factors were analyzed.

Results

Median survival was 7.5 months. The 3-tiered SCLC grade score based on the sum of adverse prognostic features was significantly associated with survival (p<0.001): A higher point sum resulted in shorter survival. However, in our validation cohort, age affected survival to the same degree as several parameters that were part of the score.

Conclusion

This validation study supports the international applicability of the SCLC grade model. Age, which has also been identified as a relevant prognostic factor in other previous studies (including the SCLC Graded Prognostic Assessment), may deserve consideration when trying to optimize survival prediction. Given that different studies identified different age limits, e.g., 70 or 75 years, merged databases are needed to provide definitive conclusions.

Modern Stereotactic Radiotherapy for Brain Metastases from Lung Cancer: Current Trends and Future Perspectives Based on Integrated Translational Approaches

Brain metastases (BMs) represent the most frequent metastatic event in the course of lung cancer patients, occurring in approximately 50% of patients with non-small-cell lung cancer (NSCLC) and in up to 70% in patients with small-cell lung cancer (SCLC). Thus far, many advances have been made in the diagnostic and therapeutic procedures, allowing improvements in the prognosis of these patients. The modern approach relies on the integration of several factors, such as accurate histological and molecular profiling, comprehensive assessment of clinical parameters and precise definition of the extent of intracranial and extracranial disease involvement. The combination of these factors is pivotal to guide the multidisciplinary discussion and to offer the most appropriate treatment to these patients based on a personalized approach. Focal radiotherapy (RT), in all its modalities (radiosurgery (SRS), fractionated stereotactic radiotherapy (SRT), adjuvant stereotactic radiotherapy (aSRT)), is the cornerstone of BM management, either alone or in combination with surgery and systemic therapies. We review the modern therapeutic strategies available to treat lung cancer patients with brain involvement. This includes an accurate review of the different technical solutions which can be exploited to provide a "state-of-art" focal RT and also a detailed description of the systemic agents available as effective alternatives to SRS/SRT when a targetable molecular driver is present. In addition to the validated treatment options, we also discuss the future perspective for focal RT, based on emerging clinical reports (e.g., SRS for patients with many BMs from NSCLC or SRS for BMs from SCLC), together with a presentation of innovative and promising findings in translational research and the combination of novel targeted agents with SRS/SRT.

Twenty-Month Regression Following Concurrent Conventional Whole-Brain Irradiation and Chemoimmunotherapy for ≥3.8 cm Cerebellar Metastasis From Small Cell Lung Cancer

Standard whole-brain radiotherapy (WBRT) alone for large brain metastases (BMs) from small cell lung cancer (SCLC) has limited efficacy and durability, and stereotactic radiosurgery (SRS) alone for symptomatic posterior fossa BMs >3 cm with satellite lesions is challenging. Herein, we describe the case of a 73-year-old female presenting with treatment-naïve SCLC and 15 symptomatic multiple BMs, including a ≥3.8-cm cerebellar mass (≥17.7 cm3) and two adjacent lesions; otherwise, the SCLC was confined to the thorax. The patient was initially treated concurrently with conventional WBRT (30 Gy in 10 fractions) without boost and chemoimmunotherapy (CIT) consisting of carboplatin, etoposide, and atezolizumab. Atezolizumab was excluded during irradiation. Five months after WBRT, the large cerebellar lesion had remarkably regressed, and the smaller lesions (≤17 mm) showed complete responses (CRs) without local progression at 20 months. However, six and 16 months after WBRT, the thoracic lesions had progressed, and although amrubicin was administered, four new BMs, including pons involvement, had developed, respectively. Despite the CRs of the four BMs following SRS (49.6 Gy in eight fractions) and the sustained regression of the thoracic lesions, meningeal dissemination and multiple new BMs were evident 3.5 months post-SRS. The small remnant of the large BM and/or newly developed BMs abutting the cerebrospinal fluid (CSF) space could have led to CSF dissemination, the presumed cause of the patient's death. Taken together, concurrent chemo-WBRT and subsequent CIT can provide excellent and durable tumor responses for SCLC BMs, but may not be fully sufficient for BMs ≥3.8 cm. Therefore, in cases with large lesions, focal dose escalation of the large lesions, consolidative thoracic radiotherapy, and dose de-escalation in the macroscopically unaffected brain region may prevent or attenuate CSF dissemination, new BM development, and adverse effects and thus should be considered.

The Management and Outcomes of Patients with Extra-Pulmonary Neuroendocrine Neoplasms and Brain Metastases

Background: Brain metastases (BMs) in patients with extra-pulmonary neuroendocrine neoplasms (EP–NENs) are rare, and limited clinical information is available. The aim of this study was to detail the clinicopathological features, management and outcomes in patients with EP–NENs who developed BMs. Methods: A retrospective single-centre analysis of consecutive patients with EP–NENs (August 2004–February 2020) was conducted. Median overall survival (OS)/survival from BMs diagnosis was estimated (Kaplan–Meier). Results: Of 730 patients, 17 (1.9%) had BMs, median age 61 years (range 15–77); 8 (53%) male, unknown primary NEN site: 40%. Patients with BMs had grade 3 (G3) EP–NENs 11 (73%), G2: 3 (20%), G1: 1 (7%). Eight (53%) had poorly differentiated NENs, 6 were well-differentiated and 1 was not recorded. Additionally, 2 (13%) patients had synchronous BMs at diagnosis, whilst 13 (87%) developed BMs metachronously. The relative risk of developing BMs was 7.48 in patients with G3 disease vs. G1 + G2 disease (p = 0.0001). Median time to the development of BMs after NEN diagnosis: 15.9 months (range 2.5–139.5). Five patients had a solitary BM, 12 had multiple BMs. Treatment of BMs were surgery (n = 3); radiotherapy (n = 5); 4: whole brain radiotherapy, 1: conformal radiotherapy (orbit). Nine (53%) had best supportive care. Median OS from NEN diagnosis was 23.6 months [95% CI 15.2–31.3]; median time to death from BMs diagnosis was 3.0 months [95% CI 0.0–8.3]. Conclusion: BMs in patients with EP–NENs are rare and of increased risk in G3 vs. G1 + G2 EP–NENs. Survival outcomes are poor, and a greater understanding is needed to improve therapeutic outcomes.

Management Strategies for Large Brain Metastases

Brain metastases represent the most common intracranial neoplasm and pose a significant disease burden on the individual and the healthcare system. Although whole brain radiation therapy was historically a first line approach, subsequent research and technological advancements have resulted in a larger armamentarium of strategies for treatment of these patients. While chemotherapeutic options remain limited, surgical resection and stereotactic radiosurgery, as well as their combination therapies, have shifted the paradigms for managing intracranial metastatic disease. Ultimately, no single treatment is shown to be consistently effective across patient groups in terms of overall survival, local and distant control, neurocognitive function, and performance status. However, close consideration of patient and tumor characteristics may help delineate more favorable treatment strategies for individual patients. Here the authors present a review of the recent literature surrounding surgery, whole brain radiation therapy, stereotactic radiosurgery, and combination approaches.

Clinical Activity and Safety of Anlotinib Combined with PD-1 Blockades for Patients with Previously Treated Small Cell Lung Cancer

Objective

Anlotinib was the standard monotherapy for patients with previously treated small cell lung cancer (SCLC) in recent years. Programmed cell death protein 1 (PD-1) blockade combined with antiangiogenic targeted drugs have proved to play a synergistic action for cancer treatment clinically. Consequently, the present study was to investigate the efficacy and safety of anlotinib combined with PD-1 blockades for patients with previously treated SCLC.

Methods

A total of 36 patients with SCLC who were treated with at least one previous systemic chemotherapy regimen participated in this study retrospectively. All the patients were administered with anlotinib plus PD-1 blockades therapy. Clinical activity was assessed according to the change of target lesion by imaging evidence and all the subjects were followed up regularly. Safety profiles were collected and documented during the treatment. Univariate analysis was carried out using Log rank test and multivariate analysis was adjusted by Cox regression analysis.

Results

All the 36 patients with previously treated SCLC were able to have their efficacy and safety profile evaluated. The best overall response of the combination regimen showed that complete response was observed in one patient, partial response was noted in 9 patients, stable disease was reported in 19 patients, progressive disease was seen in 7 patients. Therefore, the objective response rate (ORR) of the 36 patients was 27.8% (95% CI: 14.2-45.2%), disease control rate (DCR) was 80.6% (95% CI: 64.0-91.8%). Regarding the prognostic data, the median PFS and OS of the 36 patients was 4.6 months (95% CI: 3.13-6.07) and 9.3 months (95% CI: 3.30-15.30), respectively. The most common treatment-related adverse reactions were hypertension (52.8%), fatigue (47.2%), diarrhea (38.9%), hand and foot reaction (38.9%) and dermal toxicity (33.3%). Furthermore, multivariate Cox regression analysis for PFS indicated that ECOG performance status was an independent factor to predict PFS.

Conclusion

Anlotinib combined with PD-1 blockades regimen preliminarily demonstrated encouraging efficacy and tolerable safety for patients with previously treated SCLC. The conclusion should be validated in prospective clinical trials subsequently.