Prophylactic cranial irradiation in extensive disease small-cell lung cancer: short-term health-related quality of life and patient reported symptoms: results of an international Phase III randomized controlled trial by the EORTC Radiation Oncology and Lung Cancer Groups

Construction of a nomogram to guide prophylactic cranial irradiation in extensive‑stage small cell lung cancer

Patients with extensive-stage small cell lung cancer (ES-SCLC) have a high risk of brain metastasis (BM). However, to the best of our knowledge, the risk factors for BM remain unclear. The present study aimed to investigate the risk factors and establish a prediction model for BM in patients with ES-SCLC. A total of 156 patients with ES-SCLC who had no BM and achieved a partial or complete response between January 2020 and March 2023 were included. Patients were randomly divided into training (n=109) and validation (n=47) cohorts. Factors associated with BM were assessed in the training cohort. Univariate and Cox multivariate analyses were performed to evaluate patients with ES-SCLC. Cox multivariate analysis identified oligometastasis [hazard ratio (HR), 0.35; 95% CI, 0.14-0.85; P=0.021], sex (HR, 2.48; 95% CI, 1.05-5.85; P=0.038) and baseline adrenal metastasis (HR, 2.85; 95% CI, 1.54-5.21; P<0.001) as independent risk factors for BM. A nomogram model was constructed to predict intracranial progression-free survival (iPFS). The areas under the receiver operating characteristic curves for the 9-, 12- and 18-month iPFS in the training cohort were 0.77, 0.74 and 0.75, respectively. The nomogram prediction and actual validation cohorts demonstrated good agreement. Among the high-risk factors for BM, the overall survival analysis demonstrated that non-oligometastasis and baseline adrenal metastasis were unfavorable prognostic factors. The present nomogram may aid risk assessment for BM in patients with ES-SCLC and guide prophylactic cranial irradiation.

Hippocampal protection during preventive cranial irradiation and neurocognitive functions in patients with small cell lung cancer

Background

In small cell lung cancer (SCLC), limiting the radiation dose in the hippocampus area during preventive cranial irradiation (PCI) can reduce nerve injury and cognitive decline. This study was done to compare changes in cognitive functions between hippocampal-protected (3D-H) and non-hippocampal-protected (3D) patients during PCI.

Materials and methods

the study group included 113 patients with SCLC qualified to PCI divided in two subgroups: 3D-H (n = 74) and 3D (n = 39). Two diagnostic and screening tests, Mini-Mental State Examination (MMSE) Short Scale and Montreal Cognitive Assessment (MoCA) Scale, have been applied before the start of irradiation, immediately after and 3 months after PCI.

Results

The doses delivered to the volume of the left and right hippocampus were similar and amounted to 12.00 Gy and 12.05 Gy, respectively. There were no differences between 3D-H and 3D groups in the MoCA and MMSE tests at any time point. In both groups the values in MoCA and MMSE scales differed between time points I, II and III. The patients in the 3D-H group were less likely than patients in 3D group to experience significant cognitive decline on the MoCA scale (p = 0.003), but not on the MMSE scale (p = 0.103).

Conclusions

Following PCI, SCLC patients experience significant cognitive decline, even when the radiation dose in the hippocampal area is reduced. This trend continues for at least 3 months following the PCI. In hippocampal-protected patients significant cognitive decline assessed on the MoCA scale is less common than in non-hippocampal-protected patients.

Prophylactic cranial irradiation for limited-stage small-cell lung cancer in the modern magnetic resonance imaging era may be omitted: a propensity score-matched analysis

We aimed to clarify whether prophylactic cranial irradiation (PCI) is associated with improved outcomes in limited-stage small-cell lung cancer (LS-SCLC) in the current era of magnetic resonance imaging (MRI). Data from patients with LS-SCLC who achieved a complete response to definitive chemoradiotherapy (CRT) at two medical centers were retrospectively reviewed. Propensity score-matching was performed in a 2:1 ratio to balance the baseline characteristics of the no-PCI and PCI groups. The endpoints were the incidence of brain metastasis (BM), neurological causes of death and overall survival (OS). Overall, 80% patients underwent head MRI during the initial staging and 75 patients (no-PCI, n = 50; PCI, n = 25) were matched. Their baseline characteristics were generally well-balanced except for age; patients in the no-PCI group tended to be older. The median follow-up period was 29 months. Although the incidence of BMs tended to be higher in the no-PCI group (1-year BM occurrence: 26% vs 17%, P = 0.22), the incidence of multiple BMs (defined as >4 metastases) was similar between groups (1-year multiple BMs occurrence: 8% vs 9%, P = 0.65). The 2-year neurological causes of death and OS rate did not significantly differ between the groups (6% and 9%; P = 0.85; and 70% and 79%; P = 0.36, respectively). The 1-year occurrence of multiple BMs did not increase, even without PCI, when modern imaging modalities were integrated into the initial diagnosis, suggesting that PCI could be omitted after CRT, if MRI was incorporated into the initial diagnosis and follow-up.

Prophylactic cranial irradiation in patients with resected small-cell lung cancer: A systematic review and meta-analysis

Prophylactic cranial irradiation (PCI) was recommended for limited-stage small-cell lung cancer (SCLC) patients with complete or partial response to primary chemoradiotherapy. But it is still controversial regarding its role in SCLC patients who have had radical resection. This meta-analysis aims to evaluate the efficacy of PCI in resected SCLC patients. We searched PubMed, EMBASE, Web of Science, CENTRAl, and ClinicalTrials for controlled trials and cohort studies regarding PCI in postoperative SCLC patients. The correlation between PCI and post-operative outcomes in SCLC patients, including survival and brain metastasis rate (BMR), was examined using hazard ratios (HRs) and risk ratios with corresponding 95% confidence intervals. Quality of studies was assessed by the Newcastle-Ottawa Scale (NOS), and publication bias was assessed by Begg's test. Meta-analysis of eight studies with 2688 patients in total showed PCI was associated with improved overall survival (OS) for resected SCLC (HR: 0.65, 95% CI: 0.57-0.75, p < 0.01). In addition, subgroup analysis on three studies including 923 patients confirmed the protective role of postoperative PCI in N0 SCLC patients (HR: 0.79, 95% CI: 0.61-0.97, p < 0.05). There was also a significant reduction in BMR in the PCI group pooled from six studies (HR: 0.58, 95% CI: 0.40-0.85, p < 0.01). The use of PCI delayed brain recurrence and improved OS in patients with resected, stage I-III SCLC. Importantly, patients with N0 SCLC can also benefit from postoperative PCI. In future studies, PCI's role in patients with resected N0 SCLC at different T stage may need to be explored.

A biomarker exploration in small-cell lung cancer for brain metastases risk and prophylactic cranial irradiation therapy efficacy

BACKGROUND

Small-cell lung cancer (SCLC) is an aggressive malignancy with a poor prognosis. Limited-stage (LS)-SCLC comprises only one-third of SCLC cases, resulting in limited molecularly targeted therapies and treatment options. Despite advances in thoracic and cranial irradiation leading to improved outcomes, a notable proportion of patients develop brain metastasis (BM), highlighting the importance of identifying high-risk patients for tailored screening and treatment strategies.

MATERIALS AND METHODS

We analyzed baseline tumor biopsies from 180 LS-SCLC patients who received frontline definitive chemoradiotherapy (dCRT) using a 474-gene pan-cancer panel. The cumulative incidence of BM was calculated with death scored as a competing risk. Independent prognostic factors for BM risk were identified using the Fine-Gray model.

RESULTS

Alterations in the cell cycle pathway, particularly RB1 mutations, were more common in patients with BM, while FLT4 mutations were more frequent in those without BM (P=0.002 and P=0.021, respectively). Significant risk factors for BM include smoking (subdistribution hazard ratio [SHR]: 1.73; 95 % confidence interval [CI]: 1.11-2.70; P=0.016), RB1 mutations (SHR: 2.19; 95 % CI: 1.27-3.81; P=0.005), and BCL3 amplification (SHR: 2.27; 95 % CI: 1.09-4.71; P=0.028). Conversely, prophylactic cranial irradiation (PCI) (SHR: 0.39; 95 % CI: 0.25-1.60; P<0.001), FLT4 mutations (SHR: 0.26; 95 % CI: 0.07-0.98; P=0.047), and NOTCH pathway alterations (SHR: 0.65; 95 % CI: 0.43-1.00; P=0.049) were associated with a lower incidence of BM in LS-SCLC. Notably, consolidation PCI therapy did not reduce the BM risk in patients with baseline RB1 mutations, with BM occurrence probabilities of 34.7 % at 20 months and 62.6 % at 40 months.

CONCLUSION

Our study yields valuable insights into the genetic characteristics of LS-SCLC patients with and without BM, aiding the development of personalized treatment strategies. Identifying risk factors associated with the incidence and timing of BM, within the standard regimen of dCRT followed by PCI, may help optimize clinical decision-making for LS-SCLC.

Population based study on the progress in survival of primarily metastatic lung cancer patients in Germany

Lung cancer is known for its high mortality; many patients already present with metastases at the time of diagnosis. The aim of this study is to assess the impact of new treatment strategies on the survival of primarily metastatic lung cancer patients and to analyze the differences in outcomes between non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) patients. Population-based data, provided by the Robert-Koch Institute in Germany, was used and patients diagnosed between 2007 and 2018 were included in the study. We differentiated between NSCLC and SCLC patients and analyzed the survival over time for both sexes separately, using the Kaplan-Meier method. To evaluate survival advantages, we calculated multivariable hazard ratios. In total, 127,723 patients were considered for the study. We observed a moderate increase in survival over time. All patients showed an increased survival rate when undergoing chemotherapy. Minimal to no increase in survival was shown in NSCLC patients when receiving radiotherapy, whereas SCLC patients' survival time did benefit from it. NSCLC patients receiving immunotherapy showed an increase in survival as well. It can be concluded that advancements in radiotherapy, the application of chemotherapy, and the introduction of immunotherapies lead to an increased survival time of both NSCLC and SCLC primarily metastatic lung cancer patients.

Choosing the right questions - A systematic review of patient reported outcome measures used in radiotherapy and proton beam therapy

The implementation of PROMs into clinical practice has been shown to improve quality of care. This systematic review aims to identify which PROMs are suitable for implementation within routine clinical practice in a radiotherapy or PBT service.The bibliographic databases MEDLINE, EMBASE and EMCARE were searched. Articles published between 1st January 2008 to 1st June 2023, that reported PROMs being utilised as an outcome measure were included. Inclusion criteria also included being written in English, involving human patients, aged 16 and above, receiving external beam radiotherapy or PBT for six defined tumour sites. PROMs identified within the included articles were subjected to quality assessment using the COSMIN reporting guidelines. Results are reported as per PRISMA guidelines. A total of 268 studies were identified in the search, of which 52 fulfilled the inclusion criteria. The use of 39 different PROMs was reported. The PROMs identified were mostly tumour or site-specific quality of life (n = 23) measures but also included generic cancer (n = 3), health-related quality-of-life (n = 6), and symptom specific (n = 7) measures.None of the PROMs identified received a high GRADE score for good content. There were 13 PROMs that received a moderate GRADE score. The remaining PROMs either had limited evidence of development and validation within the patient cohorts investigated, or lacked relevance or comprehensiveness needed for routine PROMs collection in a radiotherapy or PBT service.This review highlights that there are a wide variety of PROMs being utilised within radiotherapy research, but most lack specificity to radiotherapy side-effects. There is a risk that by using non-specific PROMs in clinical practice, patients might not receive the supportive care that they need.

Advancing immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is a rapidly progressive neuroendocrine carcinoma that, until recently, had a very small armamentarium of effective treatments. Advances in DNA sequencing and whole transcriptomics have delineated key subtypes; therefore, SCLC is no longer viewed as a homogeneous cancer. Chemoimmunotherapy with PD1 blockade is now the standard of care for advanced disease, and ongoing research efforts are moving this strategy into the limited stage setting. Combination strategies of immunotherapy with radiation are also under active clinical trial in both limited and extensive stage disease. PLAIN LANGUAGE SUMMARY: Small cell lung cancer (SCLC) is a rapidly progressive neuroendocrine carcinoma that, until recently, had a very small armamentarium of effective treatments. Chemoimmunotherapy with immune check point inhibitors is now the standard of care for advanced disease. This comprehensive review provides an overview of current treatment strategies for SCLC, unmet needs in this patient population, and emerging treatment strategies incorporating immunotherapy that will hopefully further improve outcomes for patients.

Efficacy of Prophylactic Cranial Irradiation According to the Risk of Extracranial Recurrence in Limited-Stage Small Cell Lung Cancer

PURPOSE

We aimed to evaluate the effectiveness of prophylactic cranial irradiation (PCI) for "early brain metastasis", which occurs before extracranial recurrence (ECR), and "late brain metastasis", which occurs after ECR, in limited-stage small cell lung cancer (LS-SCLC).

Materials and Methods

We retrospectively analyzed 271 LS-SCLC patients who underwent definitive chemoradiation. All patients were initially staged with brain magnetic resonance imaging and positron emission tomography. Intracranial recurrence (ICR), ECR, progression-free rate (PFR), and overall survival (OS) were analyzed as clinical endpoints. The competing risk of the first recurrence with ICR (ICRfirst) was evaluated. Significantly associated variables in multivariate analysis of ECR were considered as ECR risk factors. Patients were stratified according to the number of ECR risk factors.

RESULTS

The application of PCI was associated with higher PFR (p=0.008) and OS (p=0.045). However, PCI was not associated with any of the clinical endpoints in multivariate analysis. The competing risk of ICRfirst was significantly decreased with the application of PCI (hazard ratio, 0.476; 95% confidence interval, 0.243 to 0.931; p=0.030). Stage III disease, sequential, and stable disease after thoracic radiation were selected as ECR risk factors. For patients without these risk factors, the application of PCI was significantly associated with increased OS (p=0.048) and a decreased risk of ICRfirst (p=0.026).

CONCLUSION

PCI may play a role in preventing early brain metastasis rather than late brain metastasis after ECR, suggesting that only patients with a low risk of ECR may currently benefit from PCI.

Prophylactic cranial irradiation for extensive stage small cell lung cancer: a meta-analysis of randomized controlled trials

BACKGROUND

Previous studies have demonstrated that prophylactic cranial irradiation (PCI) could reduce the risk of brain metastases and prolong the overall survival (OS) of patients with small cell lung cancer (SCLC). However, it remains controversial whether the efficacy and safety of PCI would be subjected to the different characteristics of patients with extensive stage of SCLC. This meta-analysis aims to evaluate the efficacy and safety of PCI in patients with extensive stage SCLC.

METHODS

PubMed, Embase, and the Cochrane Library were searched for relevant studies from inception to May, 2021. Hazard ratios (HRs) were used to measure the OS and progression-free survival (PFS), and relative risks (RRs) were employed to calculate the incidence of brain metastases, survival rate, and adverse events. Summary results were pooled using random-effect models.

RESULTS

There were 1215 articles identified, and 15 trials were included, with a total of 1,623 participants. Patients who received PCI did not result in significantly improved OS [HR=0.87, 95%CI (0.70, 1.08) p=0.417] and PFS [HR=0.81, 95%CI (0.69, 0.95) p=0.001], compared with those who did not receive PCI, while patients who received PCI had a significantly decreased incidence of brain metastases [RR=0.57, 95%CI (0.45, 0.74), p<0.001]. PCI group showed no improvements in 2-year (RR=1.03, p=0.154), 3-year (RR=0.97, p=0.072), 4-year (RR=0.71, p=0.101) and 5-year survival rates (RR=0.32, p=0.307), compared with non-PCI group, whereas the overall RR indicated that PCI was associated with a higher 1-year survival rate [RR=1.46, 95%CI (1.08, 1.97), p=0.013]. In addition, PCI treatment was shown to be associated with increased incidence of adverse events, including fatigue, dermatitis, anorexia, nausea, vomiting, malaise, and cognitive impairment.

CONCLUSION

This meta-analysis suggests that PCI can reduce the incidence of brain metastases in extensive stage SCLC. Although PCI has no significant effect on the OS, it improves 1-year survival in patients with extensive stage SCLC. However, PCI does not significantly affect 2,3,4,5-year survival and may result in a significantly increased risk of adverse events.

Risk factors for cognitive impairment in radically treated stage III NSCLC: Secondary findings of the NVALT-11 study

AIM

To identify risk factors for self-reported cognitive impairment in radically treated stage III non-small cell lung cancer (NSCLC).

METHODS

Cognitive functioning was assessed using the EORTC-QLQ-C30 at seven pre-specified time points in the phase III NVALT-11 trial (observation versus prophylactic cranial irradiation [PCI] in stage III NSCLC treated with chemo-radiotherapy±surgery). Cognition was analyzed as binary (impairment or not) and continuous outcome, respectively, using generalized estimating equation (GEE) before and after multiple imputation. A score <75 was defined as cognitive impairment. A mean difference by <10, 10-<20, ≥ 20 points was regarded as no, moderate, and large clinical effect, respectively. We categorized the cognitive impairment into four types based on changes over time: sustained, reversible, recurring, and alternating.

RESULTS

In the no-PCI arm, 43/84 [51.2%] reported cognitive impairment at least once, of which 31.4% were sustained, 25.7% reversible, 28.6% recurring, and 14.3% alternating. Results were similar in the PCI arm. Cognitive functioning at baseline was comparable in two arms and a score <75 was a significant risk factor with large effect for subsequent cognitive impairment (no-PCI: β = -22.30, p<0.001; PCI arm: β = -22.34, p<0.001; All: β = -23.47, p<0.001). Younger age (≤ 60y), squamous histology, and PCI were risk factors without clinical relevance (β > -10, p<0.05). Cognitive functioning declined over time (β = -0.26, p=0.001) except for patients with cognitive impairment at baseline (β=0.141, p=0.33).

CONCLUSION

Cognitive impairment is dynamic over time with four types. Baseline cognitive impairment (score <75) is the most important risk factor for subsequent cognitive impairment in stage III NSCLC. Note: This work has been partly reported as an oral presentation at the ESTRO 2021 meeting (OC-0176).

Evaluation of quality of life in lung cancer patients receiving radiation and Viscum album L.: a real-world data study

BACKGROUND

Lung cancer (LC) is associated with high mortality and poor quality of life (QoL). The disease as well as oncological treatments such as radiation and chemotherapy with adverse effects can impair the QoL of patients. Add-on treatment with extracts of Viscum album L. (white-berry European mistletoe, VA) has been shown to be feasible and safe and to improve the QoL of cancer patients. The aim of this study was to analyze the changes in QoL of LC patients being treated with radiation according to oncological guidelines and add-on VA treatment in a real-world setting.

METHODS

A real-world data study was conducted using registry data. Self-reported QoL was assessed by the evaluation of the European Organization of Research and Treatment Health-Related Quality of Life Core Questionnaire scale (EORTC QLQ-C30). Adjusted multivariate linear regression analyses were performed to analyze factors associated with changes in QoL at 12 months.

RESULTS

A total of 112 primary LC patients (all stages, 92% non-small-cell lung cancer, median age 70 (ICR: 63-75)), answered the questionnaires at first diagnosis and 12 months later. Assessment of 12 months changes in QoL revealed significant improvement of 27 points for pain (p = 0.006) and 17 points for nausea/vomiting (p = 0.005) in patients who received combined radiation and VA. In addition, significant improvements of 15 to 21 points for role (p = 0.03), physical (p = 0.02), cognitive (p = 0.04), and social functioning (p = 0.04) were observed in guideline treated patients receiving no radiation but add-on VA.

CONCLUSIONS

Add-on VA therapy reveals supportive effects for the QoL of LC patients. Particularly in combination with radiation a significant reduction in pain and nausea/ vomiting has been observed. Trial registration The study received ethics approval and was retrospectively registered (DRKS00013335 on 27/11/2017).

Symptom Assessment Following Surgery for Lung Cancer: A Canadian Population-based Retrospective Cohort Study

OBJECTIVE

To conduct a population-level analysis of temporal trends and risk factors for high symptom burden in patients receiving surgery for non-small cell lung cancer (NSCLC).

BACKGROUND

A population-level overview of symptoms after curative intent surgery is necessary to inform decision making and supportive care for patients with lung cancer.

METHODS

Retrospective cohort study of patients receiving surgery for stages I to III NSCLC between January 2007 and September 2018. Prospectively collection Edmonton Symptom Assessment System (ESAS) scores, linked to provincial administrative data, were used to describe the prevalence, trajectory, and predictors of moderate-to-severe symptoms in the year following surgery.

RESULTS

A total of 5350 patients, with 28,490 unique ESAS assessments, were included in the analysis. Moderate-to-severe tiredness (68%), poor wellbeing (63%), and shortness of breath (60%) were the most common symptoms reported. The rise and fall in the proportion of patients experiencing moderate-to-severe symptoms after surgery coincided with the median time to first (58 days, interquartile range: 47-72) and last cycle of chemotherapy (140 days, interquartile range: 118-168), respectively. There was eventual stabilization, albeit above the preoperative baseline, within 6 to 7 months after surgery. Female sex (relative risk [RR] 1.09- 1.26), lower income (RR 1.08-1.23), stage III disease (RR 1.15-1.43), adjuvant therapy (RR 1.09-1.42), chemotherapy within 2 weeks of an ESAS assessment (RR 1.14-1.73), and pneumonectomy (RR 1.05-1.15) were associated with moderate-to-severe symptoms following surgery.

CONCLUSIONS

Knowledge of population-level prevalence, trajectory, and predictors of moderate-to-severe symptoms after surgery for NSCLC can be used to facilitate shared decision making and improve symptom management throughout the course of illness.

Memantine in the Prevention of Radiation-Induced Brain Damage: A Narrative Review

Simple Summary

Decline in cognitive function is a major problem for patients undergoing whole-brain radiotherapy (WBRT). Scientific interest has increased due to the high dropout rate of patients in the first months after WBRT and the early onset of cognitive decline. Therefore, the study of antiglutamatergic pharmacological prophylaxis and hippocampal-sparing WBRT techniques has been deepened based on the knowledge of the mechanisms of hyperglutamatergic neurotoxicity and the role of some hippocampal areas in cognitive decline. In order to provide a summary of the evidence in this field, and to foster future research in this setting, this literature review presents current evidence on the prevention of radiation-induced cognitive decline and particularly on the role of memantine.

Abstract

Preserving cognitive functions is a priority for most patients with brain metastases. Knowing the mechanisms of hyperglutamatergic neurotoxicity and the role of some hippocampal areas in cognitive decline (CD) led to testing both the antiglutamatergic pharmacological prophylaxis and hippocampal-sparing whole-brain radiotherapy (WBRT) techniques. These studies showed a relative reduction in CD four to six months after WBRT. However, the failure to achieve statistical significance in one study that tested memantine alone (RTOG 0614) led to widespread skepticism about this drug in the WBRT setting. Moreover, interest grew in the reasons for the strong patient dropout rates in the first few months after WBRT and for early CD onset. In fact, the latter can only partially be explained by subclinical tumor progression. An emerging interpretation of the (not only) cognitive impairment during and immediately after WBRT is the dysfunction of the limbic and hypothalamic system with its immune and hormonal consequences. This new understanding of WBRT-induced toxicity may represent the basis for further innovative trials. These studies should aim to: (i) evaluate in greater detail the cognitive effects and, more generally, the quality of life impairment during and immediately after WBRT; (ii) study the mechanisms producing these early effects; (iii) test in clinical studies, the modern and advanced WBRT techniques based on both hippocampal-sparing and hypothalamic-pituitary-sparing, currently evaluated only in planning studies; (iv) test new timings of antiglutamatergic drugs administration aimed at preventing not only late toxicity but also acute effects.

Radiation therapy for extensive-stage small-cell lung cancer in the era of immunotherapy

Unlike non-small-cell lung cancer (NSCLC), the progression of small-cell lung cancer (SCLC) is slow. Extensive-stage SCLC (ES-SCLC) is a serious threat to human health, with a 5-year survival rate of <7%. Chemotherapy has been the first-line treatment for the past 30 years. The anti-PD-L1 checkpoint blockades durvalumab and atezolizumab have greatly prolonged overall survival and have become the standard first-line therapy for ES-SCLC since the CASPIAN and IMpower133 trials. In the era of chemotherapy, radiation therapy (RT), including thoracic radiation therapy (TRT) and brain radiation therapy (BRT), has shown clinical effects in randomized and retrospective studies on ES-SCLC. RT-immunotherapy has shown exciting synergistic effects in NSCLC. For ES-SCLC, the clinical effects of combining TRT/BRT with immunotherapy have not yet been systematically explored. In this review, we found that studies on RT-immunotherapy in ES-SCLC are relatively few and limited to early phase studies focusing on toxicity. The efficacy and safety profiles of early phase studies encourage prospective clinical trials. In this review, we discuss the best population, optimum TRT dose, proper TRT time, and strategies for reducing radiation-induced neurotoxicity. Furthermore, we suggest that biomarkers and patient performance status should be fully assessed before RT-immunotherapy treatment. Prospective trials are needed to provide more evidence for RT-immunotherapy applications in ES-SCLC.

Prophylactic Cranial Irradiation for Extensive-Stage Small-Cell Lung Cancer: A Controversial Area

Small-cell lung cancer (SCLC) is a highly aggressive malignant tumor that is prone to lead to the development of brain metastases (BM). The application of prophylactic cranial irradiation (PCI) has been regarded as an important technological advance made in cancer therapy to reduce the occurrence of BM and improve patient survival. The benefits of PCI in the treatment of limited-stage SCLC have been confirmed. However, there has been continuous controversy about the indications and advantages of PCI for extensive-stage SCLC (ES-SCLC) because of the conflicting results from two prospective trials. In this review, we aimed to discuss the relevant controversy and progress made in the clinical application of PCI in ES-SCLC.

Outcomes of prophylactic cranial irradiation in patients with small cell lung cancer in the modern era of baseline magnetic resonance imaging of the brain

BACKGROUND

For decades many patients with small cell lung cancer (SCLC) have been offered prophylactic cranial irradiation (PCI) to prevent brain metastases (BM). However, the role of PCI is debated in the modern era of increased brain magnetic resonance imaging (MRI) availability. BM in SCLC patients may respond to chemotherapy, and if a negative MRI is used in the decision to use of PCI in the treatment strategy, the timing of brain MRI may be crucial when evaluating the effect of PCI. This retrospective study investigates the impact of PCI outcomes in patients with SCLC staged with brain MRI prior to chemotherapy.

MATERIALS AND METHODS

This study included 245 patients diagnosed SCLC/mixed NSCLC-SCLC treated between 2012 and 2019. The population was analyzed separately for limited disease (LS-SCLC) and extensive disease (ES-SCLC). Patients were divided into groups based on baseline brain MRI prior to chemotherapy and PCI. The primary endpoint was time to symptomatic BM. Secondary endpoints were overall survival (OS), and progression-free survival (PFS).

RESULTS

In patients with LS-SCLC staged with brain MRI the probability of developing symptomatic BM at one year was 4% vs. 22% (p < 0.05), median OS was 55 vs. 24 months (p < 0.05), and median PFS was 30 vs. 10 months (p < 0.05) with and without PCI, respectively. No differences in probability of symptomatic BM and survival outcomes were observed in ES-SCLC. In a multivariate regression analysis, no variables were statistically significant associated with the risk of developing symptomatic BM in patients with LS-SCLC and ES-SCLC. For patients with ES-SCLC staged with brain MRI, PS (HR = 3.33, CI; 1.41-7.89, p < 0.05) was associated with poor survival.

CONCLUSION

This study found that PCI in LS-SCLC patients staged with brain MRI had lower incidence of symptomatic BM and improved survival outcomes suggesting PCI as standard of care. Similar benefit of PCI in patients with ES-SCLC was not found.

The overall survival impact of prophylactic cranial irradiation in limited-stage small-cell lung cancer: a systematic review and meta-analysis

•

PCI for LS-SCLC patients has become more controversial.

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Literature search on PCI impact on overall survival in LS-SCLC yielded 28 studies.

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Meta-analysis of adjusted HRs revealed pooled HR of 0.62 (95% CI: 0.57–0.69).

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Findings support PCI in current practice while awaiting prospective trial results.

Background

Prophylactic cranial irradiation (PCI) for limited-stage small-cell lung cancer (LS-SCLC) patients has become more controversial. Since the publication of the systematic review by Aupérin et al. in 1999, no randomized controlled trials regarding PCI in LS-SCLC have been completed. The aim of this study was to systematically review and meta-analyze the effect of PCI on overall survival (OS) in patients with LS-SCLC.

Methods

A systematic search was conducted in the databases of MEDLINE (PubMed), Embase and the Cochrane library. Only studies that reported an adjusted hazard ratio (aHR), indicating the effect of PCI versus no PCI on OS (adjusted for confounders) in patients with LS-SCLC were included for critical appraisal and meta-analysis. A pooled aHR estimate was calculated using a random-effects model.

Results

Pooling of 28 retrospective studies including a total of 18,575 patients demonstrated a significant beneficial effect of PCI versus no PCI on OS with a pooled aHR of 0.62 (95% CI: 0.57–0.69). Substantial heterogeneity of reported aHRs among studies was observed (I² = 65.9%). Subgroup analyses revealed that this heterogeneity could partly be explained by study sample size. The pooled aHR among 7 versus 21 studies with a sample size of > 300 versus ≤ 300 patients was 0.79 (95% CI: 0.64–0.97) versus 0.56 (95% CI: 0.46–0.69; p < 0.001), respectively.

Conclusions

This meta-analysis demonstrates a significant beneficial effect of PCI on OS in patients with LS-SCLC. Larger studies reported a milder beneficial effect, possibly due to a decreased risk of model overfitting. Serious risk of selection and confounding bias were of concern due to the lack of prospective trials. These results support the role of PCI in standard clinical practice in patients with LS-SCLC while awaiting results of prospective trials on alternative strategies.

Treatment and Prevention of Brain Metastases in Small Cell Lung Cancer

Central nervous system (CNS) metastasis will develop in 50% of small cell lung cancer (SCLC) patients throughout disease course. Development of CNS metastasis poses a particular treatment dilemma due to the accompanied cognitive changes, poor permeability of the blood-brain barrier to systemic therapy and relatively advanced state of disease. Survival of patients with untreated SCLC brain metastases is generally <3 months with whole brain radiotherapy used as first-line management in most SCLC patients. To prevent development of CNS metastasis prophylactic cranial irradiation (PCI) is recommended in limited stage disease, after response to chemotherapy and radiation, while PCI may be considered in extensive stage disease after favorable response to upfront treatment. Neurocognitive toxicity with whole brain radiotherapy and PCI is a concern and remains difficult to predict. The mechanism of toxicity is likely multifactorial, but a potential mechanism of injury to the hippocampus has led to hippocampal sparing radiation techniques. Treatment of established non-small cell lung cancer CNS metastases has increasingly focused on using stereotactic radiotherapy (SRS) and it is tempting to extrapolate these results to SCLC. In this review, we explore the evidence surrounding the prediction, prevention, detection, and treatment of CNS metastases in SCLC. We further review whether existing evidence supports extrapolating less toxic treatments to SCLC patients with CNS metastases and discuss trials that may shed more light on this question.

Prophylactic cranial irradiation (PCI), hippocampal avoidance (HA) whole brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS) in small cell lung cancer (SCLC): Where do we stand?

Small cell lung cancer (SCLC) is an aggressive form of lung cancer associated with an increased risk of develping brain metastases (BM), which are a significant cause of morbidity and mortality. Prophylactic cranial irradiation (PCI) was first introduced in the 1970s with the aim of reducing BM incidence and improving survival and quality of life (QoL). Prospective clinical trials and meta-analyses have demonstrated its effectiveness in reducing BM incidence and improving survival, across all stages of the disease following response to induction chemotherapy. Despite its long history, "unknowns" surrounding PCI use still exist and there are particular subgroups of patients for which its use remains controversial. PCI is known to cause neurocognitive toxicity which can have a significant impact on a patient's QoL. Strategies to minimise this, including the use of hippocampal avoidance radiotherapy techniques, neuroprotective drugs and stereotactic radiosurgery in place of whole brain radiotherapy for the treatment of BM, are under evaluation. This review offers a summary of the key PCI trials published to date and the current treatment recommendations based on available evidence. It also discusses the key questions being addressed in ongoing clinical trials and highlights others where there is currently a knowledge gap and therefore where further data are urgently required.

Randomized Phase III Trial of Prophylactic Cranial Irradiation With or Without Hippocampal Avoidance for Small-Cell Lung Cancer (PREMER): A GICOR-GOECP-SEOR Study

PURPOSE

Radiation dose received by the neural stem cells of the hippocampus during whole-brain radiotherapy has been associated with neurocognitive decline. The key concern using hippocampal avoidance-prophylactic cranial irradiation (HA-PCI) in patients with small-cell lung cancer (SCLC) is the incidence of brain metastasis within the hippocampal avoidance zone.

METHODS

This phase III trial enrolled 150 patients with SCLC (71.3% with limited disease) to standard prophylactic cranial irradiation (PCI; 25 Gy in 10 fractions) or HA-PCI. The primary objective was the delayed free recall (DFR) on the Free and Cued Selective Reminding Test (FCSRT) at 3 months; a decrease of 3 points or greater from baseline was considered a decline. Secondary end points included other FCSRT scores, quality of life (QoL), evaluation of the incidence and location of brain metastases, and overall survival (OS). Data were recorded at baseline, and 3, 6, 12, and 24 months after PCI.

RESULTS

Participants' baseline characteristics were well balanced between the two groups. The median follow-up time for living patients was 40.4 months. Decline on DFR from baseline to 3 months was lower in the HA-PCI arm (5.8%) compared with the PCI arm (23.5%; odds ratio, 5; 95% CI, 1.57 to 15.86; P = .003). Analysis of all FCSRT scores showed a decline on the total recall (TR; 8.7% v 20.6%) at 3 months; DFR (11.1% v 33.3%), TR (20.3% v 38.9%), and total free recall (14.8% v 31.5%) at 6 months, and TR (14.2% v 47.6%) at 24 months. The incidence of brain metastases, OS, and QoL were not significantly different.

CONCLUSION

Sparing the hippocampus during PCI better preserves cognitive function in patients with SCLC. No differences were observed with regard to brain failure, OS, and QoL compared with standard PCI.

Recent developments in the treatment of small cell lung cancer

Small cell lung cancer (SCLC) comprises about 15% of all lung cancers. It is an aggressive disease, with early metastasis and a poor prognosis. Until recently, SCLC treatment remained relatively unchanged, with chemotherapy remaining the cornerstone of treatment. In this overview we will highlight the recent advances in the field of staging, surgery, radiotherapy and systemic treatment. Nevertheless, the prognosis remains dismal and there is a pressing need for new treatment options. We describe the progress that has been made in systemic treatment by repurposing existing drugs and the addition of targeted treatment. In recent years, immunotherapy entered the clinic with high expectations of its role in the treatment of SCLC. Unravelling of the genomic sequence revealed new possible targets that may act as biomarkers in future treatment of patients with SCLC. Hopefully, in the near future, we will be able to identify patients who may benefit from targeted therapy or immunotherapy to improve prognoses.

Shared decision-making for prophylactic cranial irradiation in extensive-stage small-cell lung cancer: an exploratory study

Background

Prophylactic cranial irradiation (PCI) offers extensive-stage small-cell lung cancer (ES-SCLC) patients a lower chance of brain metastasis and slightly longer survival but is associated with a short-term decline in quality of life due to side-effects. This tradeoff between survival and quality of life makes PCI suitable for shared decision-making (SDM), where patients and clinicians make treatment decisions together based on clinical evidence and patient preferences. Despite recent clinical practice guidelines recommending SDM for PCI in ES-SCLC, as well as the heavy disease burden, research into SDM for lung cancer has been scarce. This exploratory study presents patients’ experiences of the SDM process and decisional conflict for PCI.

Methods

Radiation oncologists (n=7) trained in SDM applied it in making the PCI decision with ES-SCLC patients (n=25). We measured patients’ preferred level of participation (Control Preferences Scale), the level of SDM according to both groups (SDM-Q-9 and SDM-Q-Doc), and patients’ decisional conflict [decisional conflict scale (DCS)].

Results

Seventy-nine percent of patients preferred a collaborative role in decision-making, and median SDM scores given by patients and clinicians were 80 (IQR: 75.6–91.1) and 85.2 (IQR: 78.7–88.9) respectively, indicating satisfaction with the process. However, patients experienced considerable decisional conflict. Over 50% lacked clarity about which choice was suitable for them and were unsure what to choose. Sixty-four percent felt they did not know enough about the harms and benefits of PCI, and 60% felt unable to judge the importance of the harms/benefits in their life.

Conclusions

ES-SCLC patients prefer to be involved in their treatment choice for PCI but a substantial portion experiences decisional conflict. Better information provision and values clarification may support patients in making a choice that reflects their preferences.

Prophylactic cranial irradiation confers favourable prognosis for patients with limited-stage small cell lung cancer in the era of MRI: A propensity score-matched analysis

INTRODUCTION

Prophylactic cranial irradiation (PCI) is recommended for patients with limited-stage small cell lung cancer (LS-SCLC) who achieve good response after chemoradiotherapy. But PCI is neurotoxic. Magnetic resonance imaging (MRI) is the standard tool for evaluating brain metastasis (BM). This study was to retrospectively analyse the necessity of PCI in the era of MRI in LS-SCLC.

METHODS

From July 2013 to June 2017, 190 patients with LS-SCLC who were treated with definitive chemoradiotherapy were included and analysed in this study. They were divided into the PCI group and non-PCI group. Propensity score matching (PSM) analysis was used to balance the variable differences. The Kaplan-Meier method was applied to estimate survival with log-rank test to ascertain significance between different groups.

RESULTS

Seventy-seven patients (40.5%) received PCI after chemoradiotherapy. After adjustment for propensity scores, 69 pairs of patients were matched between two groups. After PSM, the 1-year and 3-year OS rates were 96.9% and 48.5% in PCI group versus 89.9% and 25.0% in non-PCI group (HR: 0.419, 95% CI: 0.251-0.701, P = 0.001). The 1-year and 3-year BMFS in PCI group were 96.8% and 67.5% versus 62.3% and 37.9% in non-PCI group (HR: 0.247, 95% CI: 0.132-0.460, P < 0.001).

CONCLUSION

For patients showing no BM on MRI after definitive CRT, PCI confers less BM and better OS in LS-SCLC.

Low-Dose Radiation Therapy: A New Treatment Strategy for Alzheimer's Disease?

Alzheimer's disease (AD) is a neurodegenerative disease characterized by extracellular amyloid-β (Aβ) peptide aggregates, forming amyloid plaques, and intracellular deposits of phosphorylated tau. Neuroinflammation is now considered as the third hallmark of AD. The majority of clinical trials tested pharmacological strategies targeting amyloid, tau, and neuroinflammation, with disappointing results overall. In parallel, innovative strategies exploring other pathways and approaches are being tested. In this article, we focus on the rationale and preliminary preclinical evidence for a novel application to AD of a widely used therapeutic strategy for oncological and benign conditions: low-dose radiation therapy (LD-RT). LD-RT has shown to be effective against systemic amyloid deposits, as well as against chronic inflammatory diseases, and could thus be able to modulate amyloid load and neuroinflammation in AD. The anti-amyloid effect could be possibly mediated by the LD-RT action on the β-sheet structure of amyloid fibrils, by breaking H-bonds, and depolymerize glucoaminoglycans which are highly radiation-sensitive molecules associated with amyloid fibrils. The anti-inflammatory effect could be linked to the decrease of leukocytes-endothelial cells interactions and to the stimulation of the release of anti-inflammatory molecules. One preclinical study has observed a dramatic reduction of amyloid plaques 4 weeks post-RT, more important with fractionated protocols at low doses than hypofractionated single dose treatments, associated with modulation of inflammatory and anti-inflammatory cytokines and cognitive improvement. Ongoing Phase I clinical trials will test the ability of LD-RT to hold these promises.

Low Dose Brain Irradiation Reduces Amyloid-β and Tau in 3xTg-AD Mice

We have previously reported that low doses of external beam ionizing irradiation reduced amyloid-β (Aβ) plaques and improved cognition in APP/PS1 mice. In this study we investigated the effects of radiation in an age-matched series of 3xTg-AD mice. Mice were hemibrain-irradiated with 5 fractions of 2 Gy and sacrificed 8 weeks after the end of treatment. Aβ and tau were assessed using immunohistochemistry and quantified using image analysis with Definiens Tissue Studio. We observed a significant reduction in Aβ plaque burden and tau staining; these two parameters were significantly correlated. This preliminary data is further support that low doses of radiation may be beneficial in Alzheimer's disease.

Hippocampal avoidance in prophylactic cranial irradiation for small cell lung cancer: benefits and pitfalls

Small cell lung cancers (SCLC) are a group of cancers that are clinically and pathologically different from other lung cancers. They are associated with high recurrence rates and mortality, and many patients present with metastatic disease. Approximately ten percent of SCLC patients have brain metastases at time of diagnosis, and the cumulative incidence of brain metastases increases to more than fifty percent at two years, even with optimal treatment. Hence, in patients without brain metastases at presentation, prophylactic cranial irradiation (PCI) is an important component of treatment along with systemic chemotherapy and radiotherapy. The goal of PCI is to decrease the incidence of subsequent symptomatic brain metastases in patients who show an initial response to the systemic treatment. Various clinical trials have evaluated the utility of PCI and found substantial benefit. Unfortunately, the long-term toxicity associated with PCI, namely the neuro-cognitive impairment that may develop in patients as a result of the radiation toxicity to the hippocampal areas of the brain, has raised concern both for patients and their treating physicians. Various techniques have been tried to ameliorate the neuro-cognitive impairment associated with PCI, including pharmacological agents and highly conformal hippocampal avoidance radiation. All of these have shown promise, but there is a lack of clarity about the optimal way forward. Hippocampal avoidance PCI appears to be an excellent option and a number of groups are currently evaluating this technique. Although there is clear benefit with this specialized radiation treatment, there are also concerns about the risk of disease recurrence in the undertreated hippocampal areas. This review attempts to compile the available data regarding the benefits and pitfalls associated with hippocampal avoidance PCI in the setting of SCLC.

Prophylactic cranial irradiation in SCLC

Prophylactic cranial irradiation (PCI) has well established place in therapy for patients with limited-disease small cell lung cancer who responded to treatment. The data from randomized trials document that PCI reduces brain metastases rate from approximately 60% to 30%, and increases 3-year overall survival by approximately 5%. Currently, the dose of 25 Gy in 10 fractions is considered as standard. In attempt to reduce neuropsychological sequelae attributable to PCI hippocampal sparing techniques are employed. The existing studies suggest the benefit of hippocampal sparing in limiting memory and higher neurocognitive function losses, but with a risk of failures in the spared region. Ongoing studies will further validate the role of hippocampal sparing, both in terms of toxicity reduction and metastases prevention. PCI for patients who have undergone resection for stage I small cell lung cancer (SCLC) is not recommended, PCI may be, however, associated with a favourable outcome in SCLC patients who have undergone complete surgery in stages II−III. The role of PCI in extensive-disease (ED) SCLC has been evolving. Most recent evidence indicate that PCI is controversial in ED patients with response to initial chemotherapy and absence of brain metastases confirmed by contrast-enhanced MRI. The patients who do not receive PCI, must, however, receive periodic MRI examination during follow-up, i.e., remain under active surveillance with access to radiotherapy at brain relapse. The assessment of safety and effectiveness of hippocampal-sparing PCI, with or without drug neuroprotection in consideration of diverse combinations of radiotherapy, chemotherapy and immunotherapy create a background for future directions of research.

Impact of prophylactic cranial irradiation and hippocampal sparing on 18F-FDG brain metabolism in small cell lung cancer patients

BACKGROUND AND PURPOSE

Prophylactic cranial irradiation (PCI) in small-cell lung cancer (SCLC) patients improves survival. However, it is also associated with cognitive impairment, although the underlying mechanisms remain poorly understood. Our study aims to evaluate the impact of PCI and potential benefit of hippocampal sparing (HS) on brain metabolism assessed by ¹⁸F-Fluoro-Deoxy-Glucose Positron Emission Tomography/Computed Tomography (¹⁸F-FDG PET/CT).

MATERIALS AND METHODS

We retrospectively included 22 SCLC patients. 50% had hippocampal-sparing (HS) PCI. ¹⁸F-FDG PET/CT was performed 144.5 ± 73 days before and 383 ± 451 days after PCI. Brain ¹⁸F-FDG PET scans were automatically segmented in 12 regions using Combined-AAL Atlas from MI-Neurology Software (Syngo.Via, Siemens Healthineers). For all atlas regions, we computed SUV Ratio using brainstem as a reference region (SUVR = SUVmean/Brainstem SUVmean) and compared SUVR before and after PCI, using a Wilcoxon test, with a level of significance of p < 0.05.

RESULTS

We found significant decreases in ¹⁸F-FDG brain metabolism after PCI in the basal ganglia (p = 0.004), central regions (p = 0.001), cingulate cortex (p < 0.001), corpus striata (p = 0.003), frontal cortex (p < 0.001), parietal cortex (p = 0.001), the occipital cortex (p = 0.002), precuneus (p = 0.001), lateral temporal cortex (p = 0.001) and cerebellum (p < 0.001). Conversely, there were no significant changes in the mesial temporal cortex (MTC) which includes the hippocampi (p = 0.089). The subgroup who received standard PCI showed a significant decrease in metabolism of the hippocampi (p = 0.033). Contrastingly, the subgroup of patients who underwent HS-PCI showed no significant variation in metabolism of the hippocampi (p = 0.783).

CONCLUSION

PCI induced a diffuse decrease in ¹⁸F-FDG brain metabolism. HS-PCI preserves metabolic activity of the hippocampi.

[The role of prophylactic cranial irradiation in small cell lung cancer]

INTRODUCTION

Prophylactic cranial irradiation (PCI) is considered standard therapeutic management in small cell lung cancer (SCLC). This is based on old randomised trials with methodological limitations, namely the absence of magnetic resonance imaging (MRI) of the brain. The aim of this study is to assess the risk not administering PCI when systematic brain imaging is applied.

METHODS

Retrospective study including untreated SCLC, without PCI and receiving brain imaging at the time of diagnosis. Kaplan-Meier and log-rank statistics were used for survival analyses.

RESULTS

Among 150 patients, 75 were possibly eligible for PCI. Thirteen patients presented with an isolated brain recurrence as the first site of progression with no other metastatic sites apparent, and in 6 patients, the brain was the only recurrent site during the whole follow-up. In the group of patients eligible for PCI, there was no statistically significant survival difference according to the brain progression status (P=0.11).

CONCLUSIONS

The expected impact of PCI seems limited in terms of overall survival and prevention of isolated brain metastases in patients having systematic brain imaging during SCLC work-up.

Patient-reported outcomes with first-line durvalumab plus platinum-etoposide versus platinum-etoposide in extensive-stage small-cell lung cancer (CASPIAN): a randomized, controlled, open-label, phase III study

OBJECTIVES

In the phase III CASPIAN study, first-line durvalumab plus etoposide in combination with either cisplatin or carboplatin (EP) significantly improved overall survival (primary endpoint) versus EP alone in patients with extensive-stage small-cell lung cancer (ES-SCLC) at the interim analysis. Here we report patient-reported outcomes (PROs).

MATERIALS AND METHODS

Treatment-naïve patients with ES-SCLC received 4 cycles of durvalumab plus EP every 3 weeks followed by maintenance durvalumab every 4 weeks until progression, or up to 6 cycles of EP every 3 weeks. PROs, assessed with the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) version 3 and its lung cancer module, the Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13), were prespecified secondary endpoints. Changes from baseline to disease progression or 12 months in prespecified key disease-related symptoms (cough, dyspnea, chest pain, fatigue, appetite loss) were analyzed with a mixed model for repeated measures. Time to deterioration (TTD) of symptoms, functioning, and global health status/quality of life (QoL) from randomization was analyzed.

RESULTS

In the durvalumab plus EP and EP arms, 261 and 260 patients were PRO-evaluable. Patients in both arms experienced numerically reduced symptom burden over 12 months or until progression for key symptoms. For the improvements from baseline in appetite loss, the between-arm difference was statistically significant, favoring durvalumab plus EP (difference, -4.5; 99% CI: -9.04, -0.04; nominal p = 0.009). Patients experienced longer TTD with durvalumab plus EP versus EP for all symptoms (hazard ratio [95% CI] for key symptoms: cough 0.78 [0.600‒1.026]; dyspnea 0.79 [0.625‒1.006]; chest pain 0.76 [0.575‒0.996]; fatigue 0.82 [0.653‒1.027]; appetite loss 0.70 [0.542‒0.899]), functioning, and global health status/QoL.

CONCLUSION

Addition of durvalumab to first-line EP maintained QoL and delayed worsening of patient-reported symptoms, functioning, and global health status/QoL compared with EP.

Current and future strategies in radiotherapy for small-cell lung cancer

Small-cell lung cancer (SCLC) accounts for 13% of all lung tumors. The standard treatment in patients with limited-stage (LS) disease is thoracic radiotherapy (TRT) combined with chemotherapy. In extensive-stage (ES) SCLC, the importance of consolidation TRT in patients with a good treatment response has become increasingly recognized. In both LS and ES disease, prophylactic cranial irradiation is recommended in patients who respond to treatment. New therapeutic approaches such as immunotherapy are being increasingly incorporated into the treatment of SCLC, although more slowly than in non-small cell lung cancer. Diverse radiation dose and fractionation schemes, administered in varying combinations with these new drugs, are being investigated. In the present article, we review and update the role of radiotherapy in the treatment of SCLC. We also discuss the main clinical trials currently underway to identify future trends.

RELEVANCE FOR PATIENTS

Radiotherapy is a critical component of multimodality treatment of SCLC. This article can help physicians to improve medical knowledge and find better ways to treat their SCLC patients.

GOECP/SEOR clinical recommendations for lung cancer radiotherapy during the COVID-19 pandemic

The coronavirus disease 2019 crisis has had a major and highly complex impact on the clinical practice of radiation oncology worldwide. Spain is one of the countries hardest hit by the virus, with devastating consequences. There is an urgent need to share experiences and offer guidance on decision-making with regard to the indications and standards for radiation therapy in the treatment of lung cancer. In the present article, the Oncological Group for the Study of Lung Cancer of the Spanish Society of Radiation Oncology reviews the literature and establishes a series of consensus-based recommendations for the treatment of patients with lung cancer in different clinical scenarios during the present pandemic.

Risk factors for neurocognitive decline in lung cancer patients treated with prophylactic cranial irradiation: A systematic review

BACKGROUND

Prophylactic cranial irradiation (PCI) reduces brain metastasis incidence in lung cancer, however with risk of neurocognitive decline. Nevertheless, risk factors for neurocognitive decline after PCI remain unclear.

METHODS

We systematically reviewed the PubMed database according to the PRISMA guideline. Inclusion criteria were: randomized clinical trials (RCTs) and observational/single arm trials evaluating PCI, including ≥20 patients, reporting neurocognitive test results for lung cancer. Primary aim: evaluate risk factors associated with neurocognitive decline after PCI.

RESULTS

Twenty records were eligible (8 different RCTs, 8 observational studies), including 3553 patients in total (858 NSCLC, 2695 SCLC) of which 73.6% received PCI. Incidence of mild/moderate cognitive decline after PCI varied from 8 to 89% (grading not always provided); for those without PCI, this was 3.4-42%. Interestingly, 23-95% had baseline cognitive impairment. Risk factors were often not reported. In one trial, both age (>60 years) and higher PCI dose (36 Gy) including twice-daily PCI were associated with a higher risk of cognitive decline. In one trial, white matter abnormalities were more frequent in the concurrent or sandwiched PCI arm, but without significant neuropsychological differences. One trial identified hippocampal sparing PCI to limit the neurocognitive toxicities of PCI and another reported an association between hippocampal dose volume effects and memory decline. As neurocognition was a secondary endpoint in most RCTs, and was assessed by various instruments with often poor/moderate compliance, high-quality data is lacking.

CONCLUSIONS

Age, PCI dose, regimen and timing might be associated with cognitive impairment after PCI in lung cancer patients, but high-quality data is lacking. Future PCI trials should collect and evaluate possible risk factors systematically.

Prophylactic Cranial Irradiation for Small-Cell Lung Cancer: Time for a Reassessment

Prophylactic cranial irradiation (PCI) has been an accepted part of the management of both limited and small-cell lung cancer; however, the data that support its use in limited-stage disease is based on an analysis of trials done before currently accepted approaches to staging (i.e., brain MRI and/or PET scanning) were available. For extensive disease, data are available from two randomized studies that are in direct conflict. This article explores the basic rationale for PCI and the evidence indicating that it is time to readdress the question of its routine use.

Strategies to prevent brain metastasis

PURPOSE OF REVIEW

The current article reviews the state of art of prevention strategies for brain metastases from solid tumors and touches both old pivotal studies and new directions of personalized molecular approaches.

RECENT FINDINGS

Prophylactic cranial irradiation (PCI) has a definite role in the prevention of relapse into the brain for patients with small cell lung cancer (SCLC) responding to chemotherapy and radiotherapy as it prolongs overall survival (OS). However, the risk of late cognitive deficit following whole brain radiotherapy (WBRT) in this patient population is still not well known. Conversely, PCI significantly reduces the incidence of brain metastases and prolongs the disease-free interval in patients with non-SCLC (NSCLC), but does not improve OS thus far. Pharmacologic prevention is a new concept driven by the efficacy of targeted agents on macrometastases from specific molecular subgroups.

SUMMARY

The future challenges for prevention of brain metastases are represented by the identification of subgroups of patients at higher risk of relapse into the brain coupled with either new WBRT strategies to better preserve cognition or effective molecular agents to target micrometastases.

Limited Stage Small Cell Bladder Cancer: Outcomes of a Contemporary Cohort

BACKGROUND: Limited stage small cell bladder cancer is curable with multi-modality therapy using external beam radiotherapy or radical cystectomy. The optimal management strategy for this rare disease is still debated, yet few case series have described patients treated after 2010. OBJECTIVE: To analyze outcomes from a contemporary cohort of patients undergoing definitive treatment. METHODS: Patients diagnosed with small cell bladder cancer after January 1, 2010 were identified from an institutional database. Clinical histories were collected by chart review. Survival outcomes were analyzed in patients who received curative-intent therapy consisting of bladder radiotherapy or cystectomy. RESULTS: Thirty patients with limited stage disease that received definitive therapy were identified. Seventeen patients received primary radiotherapy, and thirteen underwent cystectomy. Median age was 70 years. Median follow up was 39.6 months (range 7.2–95.8). The median overall survival of patients undergoing radiotherapy or cystectomy were 36.8 and 30.6 months, respectively (hazard ratio 0.99, 95% confidence interval 0.35–2.85). The median metastasis free survival for patients receiving radiotherapy was not reached, and 18.9 months in the cystectomy group (hazard ratio 0.94, 95% confidence interval 0.34–2.61). The most common sites of relapse were lymph node (n = 6) and bone (n = 5). Brain metastases were less common (n = 3). CONCLUSIONS: Patients receiving cystectomy or radiotherapy had similar outcomes in this contemporary series, but definitive comparisons are limited by the cohort size and high censoring rate (53%). Survival in our cohort is improved compared with older reports, though outcomes remain poor, reiterating the need for better therapeutic options.

Study protocol: watchful observation of patients with limited small cell lung cancer instead of the PCI-prospective, multi-center one-arm study

Background

Prophylactic cranial irradiation (PCI) is a current standard of care after confirmed response to radical chemoradiotherapy for limited disease small cell lung cancer (LD-SCLC). This standard is mostly based on results of old randomized studies when brain imaging with magnetic resonance (MRI) was not available. Survival benefit of PCI in extended disease SCLC was recently challenged by the results of randomized phase III study from Japan.

Methods

Eighty patients with LD-SCLC after response to chest chemoradiotherapy will be enrolled. Patients will be followed up by brain MRI every 3 to 6 months up to 3 years. Neurocognitive function tests will be performed at baseline and after 12 and 24 months. Patients who develop brain metastases will be irradiated with stereotactic (SRT) or whole brain RT (WBRT). The primary endpoint is overall survival. The secondary endpoints are: response rate to radiotherapy of early detected brain metastases, analysis of efficacy of SRT and WBRT; assessment and analysis of neurocognitive functions and QoL in the studied cohorts: QLQ-C30 questionnaire and the California Verbal Learning Test, Color connection test, Benton visual retention test, and verbal fluency test will be carried out.

Discussion

The results of this trial may contribute to changing of LD-SCLC clinical management by deescalating the treatment. There is a lack of prospective, recent studies in LD-SCLC patients with omission of PCI and modern radiation therapy technologies for developed brain metastases. The comprehensive neurocognitive function testing will help to assess the impact of modern radiotherapy (SRT) compared with WBRT and no-PCI in SCLC patients. A subgroup of long-term survivors, who will not develop brain metastases, will not be exposed to unnecessary brain irradiation with its deleterious consequences. The limitation of our study is a lack of parallel randomized control arm. This is a potential source of bias; however, randomized study will be difficult to complete for two major reasons: (1) limited population of LD-SCLC eligible for the study and (2) opinions of our patients, who after information and discussion about benefits and potential harms of PCI, often choose to omit PCI in our practice.

Trial registration

ClinicalTrials.gov Identifier: NCT04168281, 19 Nov. 2019.

Severe symptoms persist for Up to one year after diagnosis of stage I-III lung cancer: An analysis of province-wide patient reported outcomes

OBJECTIVES

Lung cancer is associated with significant disease- and treatment-related morbidity. The Edmonton Symptom Assessment System (ESAS) is a tool developed to elicit patients' own assessment of the severity of common cancer-associated symptoms. The objective of this study was to examine symptom severity in the 12 months following diagnosis of lung cancer, and to identify predictors of high symptom burden.

MATERIALS AND METHODS

This was a retrospective population-based cohort study, including patients with stage I-III lung cancer diagnosed between 2007-2016, and who had symptom screening in the 12 months following diagnosis. The proportion of patients reporting severe symptoms (ESAS ≥ 7) in the year following diagnosis was plotted over time. Multivariable regression models were constructed to identify factors associated with severe symptoms.

RESULTS

69,440 unique symptom assessments were reported by 11,075 lung cancer patients. Tiredness was the most prevalent severe symptom (47.3 %), followed by shortness of breath (39.4 %) and poor wellbeing (36.5 %) among all disease stages. Patients diagnosed with higher stage disease reported more severe symptoms, but symptom trajectories were similar for all stages in the year following diagnosis. Disease stage (RR 1.10-2.01), comorbidity burden (RR 1.17-1.51), degree of socioeconomic marginalization (RR1.15-1.45), and female sex (RR 1.15-1.50) were associated with reporting severe symptoms in the year following diagnosis.

CONCLUSION

Severe physical and psychological symptoms persist throughout the first year following lung cancer diagnosis, regardless of disease stage. Those at risk of experiencing high symptom burden may benefit from targeted supportive care interventions, including psychosocial support aimed at improving health-related quality of life.

Current approaches to the management of brain metastases

Brain metastases are a very common manifestation of cancer that have historically been approached as a single disease entity given the uniform association with poor clinical outcomes. Fortunately, our understanding of the biology and molecular underpinnings of brain metastases has greatly improved, resulting in more sophisticated prognostic models and multiple patient-related and disease-specific treatment paradigms. In addition, the therapeutic armamentarium has expanded from whole-brain radiotherapy and surgery to include stereotactic radiosurgery, targeted therapies and immunotherapies, which are often used sequentially or in combination. Advances in neuroimaging have provided additional opportunities to accurately screen for intracranial disease at initial cancer diagnosis, target intracranial lesions with precision during treatment and help differentiate the effects of treatment from disease progression by incorporating functional imaging. Given the numerous available treatment options for patients with brain metastases, a multidisciplinary approach is strongly recommended to personalize the treatment of each patient in an effort to improve the therapeutic ratio. Given the ongoing controversies regarding the optimal sequencing of the available and expanding treatment options for patients with brain metastases, enrolment in clinical trials is essential to advance our understanding of this complex and common disease. In this Review, we describe the key features of diagnosis, risk stratification and modern paradigms in the treatment and management of patients with brain metastases and provide speculation on future research directions.

Meta-analysis of prophylactic cranial irradiation or not in treatment of extensive-stage small-cell lung cancer: The dilemma remains

PURPOSE

The role of prophylactic cranial irradiation (PCI) in treatment of extensive-stage small-cell lung cancer (SCLC) is controversial. The aim of this study was to systematically evaluate the efficacy and safety of using PCI in the treatment of extensive-stage SCLC. In the present study, we examined whether PCI was essential for the optimal treatment of extensive-disease small-cell lung cancer.

MATERIAL AND METHODS

We searched the PubMed, Embase, Medline, and China National Knowledge Infrastructure databases to identify articles that assessed the efficacy of PCI in treating extensive-stage small-cell lung cancer patients.

RESULTS

We identified 8 studies that involved a total of 982 patients who received PCI (PCI group) and a total of 4509 patients who did not receive PCI (control group). The results showed that PCI significantly improved the 1-year overall survival rate (HR=1.50; 95% CI: 1.23-1.82; I²=67%; P<0.0001) and reduced the incidence of brain metastasis (HR=0.46; 95% CI: 0.37-0.58; I²=6%; P<0.00001).

CONCLUSION

PCI improves the 1-year overall survival rate and reduces the risk of brain metastasis in patients with extensive-stage SCLC.

Whole-brain radiotherapy plus sequential or simultaneous integrated boost for the treatment of a limited number of brain metastases in non-small cell lung cancer: A single-institution study

BACKGROUND

To compare the survival outcomes and neurocognitive dysfunction in non-small cell lung cancer (NSCLC) patients with brain metastases (BM ≤10) treated by whole-brain radiotherapy (WBRT) with sequential integrated boost (SEB) or simultaneous integrated boost (SIB).

MATERIALS

Fifty-two NSCLC patients with a limited number of BMs were retrospectively analyzed. Twenty cases received WBRT+SEB (WBRT: 3 Gy*10 fractions and BMs: 4 Gy*3 fractions; SEB group), and 32 cases received WBRT+SIB (WBRT: 3 Gy*10 fractions and BMs: 4 Gy*10 fractions; SIB group). The survival and mini-mental state examination (MMSE) scores were compared between the groups.

RESULTS

The cumulative 1-, 2-, and 3-year survival rates in the SEB vs SIB groups were 60.0% vs 47.8%, 41.1% vs 19.1%, and 27.4% vs 0%, respectively. The median survival times in the SEB and SIB groups were 15 and 10 months, respectively. The difference in survival rate was significant (P = .046). Subgroup analysis revealed that 1-, 2-, and 3-year survival rates and median survival time in the SEB group were significantly superior to those of the SIB group, especially for male patients (age <60 years) with 1-2 BMs (P < .05). The MMSE score of the SEB group at 3 months after radiation was higher than that of the SIB group (P < .05). Nevertheless, WBRT+SEB required a longer treatment time and greater cost (P < .005).

CONCLUSIONS

WBRT + SEB results in better survival outcomes than WBRT+SIB, especially for male patients (age <60 years) with 1-2 BMs. WBRT+SEB also appeared to induce less neurocognitive impairment than WBRT+SIB.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Role of Whole Brain Radiation Therapy in Adults With Newly Diagnosed Metastatic Brain Tumors

TARGET POPULATION

Adult patients (older than 18 yr of age) with newly diagnosed brain metastases.

QUESTION

If whole brain radiation therapy (WBRT) is used, is there an optimal dose/fractionation schedule?

RECOMMENDATIONS

Level 1:  A standard WBRT dose/fractionation schedule (ie, 30 Gy in 10 fractions or a biological equivalent dose [BED] of 39 Gy10) is recommended as altered dose/fractionation schedules do not result in significant differences in median survival or local control. Level 3: Due to concerns regarding neurocognitive effects, higher dose per fraction schedules (such as 20 Gy in 5 fractions) are recommended only for patients with poor performance status or short predicted survival. Level 3: WBRT can be recommended to improve progression-free survival for patients with more than 4 brain metastases.

QUESTION

What impact does tumor histopathology or molecular status have on the decision to use WBRT, the dose fractionation scheme to be utilized, and its outcomes?

RECOMMENDATIONS

There is insufficient evidence to support the choice of any particular dose/fractionation regimen based on histopathology. Molecular status may have an impact on the decision to delay WBRT in subgroups of patients, but there is not sufficient data to make a more definitive recommendation.

QUESTION

Separate from survival outcomes, what are the neurocognitive consequences of WBRT, and what steps can be taken to minimize them?

RECOMMENDATIONS

Level 2: Due to neurocognitive toxicity, local therapy (surgery or SRS) without WBRT is recommended for patients with ≤4 brain metastases amenable to local therapy in terms of size and location. Level 2:  Given the association of neurocognitive toxicity with increasing total dose and dose per fraction of WBRT, WBRT doses exceeding 30 Gy given in 10 fractions, or similar biologically equivalent doses, are not recommended, except in patients with poor performance status or short predicted survival. Level 2: If prophylactic cranial irradiation (PCI) is given to prevent brain metastases for small cell lung cancer, the recommended WBRT dose/fractionation regimen is 25 Gy in 10 fractions, and because this can be associated with neurocognitive decline, patients should be told of this risk at the same time they are counseled about the possible survival benefits. Level 3: Patients having WBRT (given for either existing brain metastases or as PCI) should be offered 6 mo of memantine to potentially delay, lessen, or prevent the associated neurocognitive toxicity.

QUESTION

Does the addition of WBRT after surgical resection or radiosurgery improve progression-free or overall survival outcomes when compared to surgical resection or radiosurgery alone?

RECOMMENDATIONS

Level 2: WBRT is not recommended in WHO performance status 0 to 2 patients with up to 4 brain metastases because, compared to surgical resection or radiosurgery alone, the addition of WBRT improves intracranial progression-free survival but not overall survival. Level 2: In WHO performance status 0 to 2 patients with up to 4 brain metastases where the goal is minimizing neurocognitive toxicity, as opposed to maximizing progression-free survival and overall survival, local therapy (surgery or radiosurgery) without WBRT is recommended. Level 3: Compared to surgical resection or radiosurgery alone, the addition of WBRT is not recommended for patients with more than 4 brain metastases unless the metastases' volume exceeds 7 cc, or there are more than 15 metastases, or the size or location of the metastases are not amenable to surgical resection or radiosurgery.The full guideline can be found at: https://www.cns.org/guidelines/guidelines-treatment-adults-metastatic-brain-tumors/chapter_3.

What is the role of radiotherapy for extensive-stage small cell lung cancer in the immunotherapy era?

Small cell lung cancer has been a difficult disease to treat with poor survival and few significant improvements in outcomes in the last three decades. Most recently the addition of atezolizumab to chemotherapy in the first-line treatment of extensive-stage small cell lung cancer (ES-SCLC) resulted in improved overall survival and progression-free survival compared to chemotherapy alone. Recent randomized studies examining both consolidative thoracic radiotherapy and prophylactic cranial irradiation (PCI) in ES-SCLC have impacted the utilization of these interventions. The approval of immune checkpoint inhibitors (ICIs) to platinum/etoposide chemotherapy for the treatment of ES-SCLC in the front-line setting may also further impact the role of radiotherapy in this disease. In this article, we review the current evidence supporting thoracic radiotherapy in ES-SCLC and discuss the promising therapeutic implications of thoracic radiation in light of the inclusion of ICIs. We also address how the increasing routine use of surveillance brain magnetic resonance imaging (MRI) and ICIs may diminish the use of PCI in ES-SCLC.