Rational and design of prophylactic cranial irradiation (PCI) and brain MRI surveillance versus brain MRI surveillance alone in patients with limited-stage small cell lung cancer achieving complete remission (CR) of tumor after chemoradiotherapy: a multicenter prospective randomized study.

BACKGROUND: Prophylactic cranial irradiation (PCI) is part of standard care in limited-stage small cell lung cancer (SCLC) at present. As evidence from retrospective studies increases, the benefits of PCI for limited-stage SCLC are being challenged. METHODS: A multicenter, prospective, randomized controlled study was designed. The key inclusion criteria were: histologically or cytologically confirmed small cell carcinoma, age ≥ 18 years, KPS ≥ 80, limited-stage is defined as tumor confined to one side of the chest including ipsilateral hilar, bilateral mediastinum and supraclavicular lymph nodes, patients have received definitive thoracic radiotherapy (regardless of the dose-fractionation of radiotherapy used) and chemotherapy, evaluated as complete remission (CR) of tumor 4-6 weeks after the completion of chemo-radiotherapy. Eligible patients will be randomly assigned to two arms: (1) PCI and brain MRI surveillance arm, receiving PCI (2.5 Gy qd to a total dose of 25 Gy in two weeks) followed by brain MRI surveillance once every three months for two years; (2) brain MRI surveillance alone arm, undergoing brain MRI surveillance once every three months for two years. The primary objective is to compare the 2-year brain metastasis-free survival (BMFS) rates between the two arms. Secondary objectives include 2-year overall survival (OS) rates, intra-cranial failure patterns, 2-year progression-free survival rates and neurotoxicity. In case of brain metastasis (BM) detect during follow-up, stereotactic radiosurgery (SRS) will be recommended if patients meet the eligibility criteria. DISCUSSION: Based on our post-hoc analysis of a prospective study, we hypothesize that in limited-stage SCLC patients with CR after definitive chemoradiotherapy, and ruling out of BM by MRI, it would be feasible to use brain MRI surveillance and omit PCI in these patients. If BM is detected during follow-up, treatment with SRS or whole brain radiotherapy does not appear to have a detrimental effect on OS. Additionally, this approach may reduce potential neurotoxicity associated with PCI.

Cranial irradiation disrupts homeostatic microglial dynamic behavior.

Cranial irradiation causes cognitive deficits that are in part mediated by microglia, the resident immune cells of the brain. Microglia are highly reactive, exhibiting changes in shape and morphology depending on the function they are performing. Additionally, microglia processes make dynamic, physical contacts with different components of their environment to monitor the functional state of the brain and promote plasticity. Though evidence suggests radiation perturbs homeostatic microglia functions, it is unknown how cranial irradiation impacts the dynamic behavior of microglia over time. Here, we paired in vivo two-photon microscopy with a transgenic mouse model that labels cortical microglia to follow these cells and determine how they change over time in cranial irradiated mice and their control littermates. We show that a single dose of 10 Gy cranial irradiation disrupts homeostatic cortical microglia dynamics during a 1-month time course. We found a lasting loss of microglial cells following cranial irradiation, coupled with a modest dysregulation of microglial soma displacement at earlier timepoints. The homogeneous distribution of microglia was maintained, suggesting microglia rearrange themselves to account for cell loss and maintain territorial organization following cranial irradiation. Furthermore, we found cranial irradiation reduced microglia coverage of the parenchyma and their surveillance capacity, without overtly changing morphology. Our results demonstrate that a single dose of radiation can induce changes in microglial behavior and function that could influence neurological health. These results set the foundation for future work examining how cranial irradiation impacts complex cellular dynamics in the brain which could contribute to the manifestation of cognitive deficits.

Prophylactic Cranial Irradiation in Limited-Stage Small Cell Lung Cancer: A Meta-Analysis.

The role of prophylactic cranial irradiation (PCI) in limited-stage small cell lung cancer (LS-SCLC) has been questioned in the era of magnetic resonance imaging (MRI). The purpose of this study was to re-evaluate the efficacy of PCI in patients with LS-SCLC. Three electronic databases were searched, including PubMed, Embase, and the Cochrane Library from January 2012 to April 2022. All relevant publications were included based on the inclusion criteria, and survival data and brain metastasis (BM) rates were extracted and pooled. Ten studies were selected which involved 532 patients who received PCI and 613 patients who did not receive PCI. In pooled estimates, PCI significantly improved overall survival (OS) and progression-free survival (PFS) [hazard ratio (HR) = 0.71, 95% confidence interval (CI): 0.61-0.82, p <0.001; HR = 0.68, 95% CI: 0.48-0.97, p = 0.03, respectively]. Additionally, the use of PCI was associated with a significant reduction in the risk of brain metastasis (BM, risk ratio = 0.64, 95% CI: 0.46-0.90, p = 0.009). In subgroup analyses. The authors found that the PCI effects on OS were independent of region and the use of brain imaging after initial treatment. These findings demonstrate that PCI improves OS and PFS while decreasing the risk of BM in patients with LS-SCLC, implying that PCI remains necessary even in the MRI era. Key Words: Prophylactic cranial irradiation, Small cell lung cancer, Magnetic resonance imaging, Brain metastasis.

Survival prediction in patients with gynecological cancer irradiated for brain metastases.

BACKGROUND AND PURPOSE: This large population-based, retrospective, single-center study aimed to identify prognostic factors in patients with brain metastases (BM) from gynecological cancers. MATERIAL AND METHODS: One hundred and forty four patients with BM from gynecological cancer treated with radiotherapy (RT) were identified. Primary cancer diagnosis, age, performance status, number of BM, presence of extracranial disease, and type of BM treatment were assessed. Overall survival (OS) was calculated using the Kaplan-Meier method and the Cox proportional hazards regression model was used for multivariable analysis. A prognostic index (PI) was developed based on scores from independent predictors of OS. RESULTS: Median OS for the entire study population was 6.2 months. Forty per cent of patients died within 3 months after start of RT. Primary cancer with the origin in cervix or vulva (p = 0.001),  Eastern Cooperative Oncology Group (ECOG) 3-4 (p < 0.001), and the presence of extracranial disease (p = 0.001) were associated with significantly shorter OS. The developed PI based on these factors, categorized patients into three risk groups with a median OS of 13.5, 4.0, and 2.4 months for the good, intermediate, and poor prognosis group, respectively. INTERPRETATION: Patients with BM from gynecological cancers carry a poor prognosis. We identified prognostic factors and developed a scoring tool to select patients with better or worse prognosis. Patients in the high-risk group have a particular poor prognosis, and omission of RT could be considered.

Grade 5 Radiation Necrosis After Whole-Brain Radiation Therapy.

Whole-brain radiation treatment is often considered for patients with leptomeningeal disease. There are limited reports of the development of radiation necrosis after whole-brain radiation treatment and fewer associating the presence of germline mutations with risk. We present a case report to highlight the need for consideration of radiosensitizing mutations when recommending radiation therapy.

Factors associated with overall survival in breast cancer patients with leptomeningeal disease (LMD): a single institutional retrospective review.

BACKGROUND: Breast cancer-related leptomeningeal disease (BC-LMD) is a dire diagnosis for 5-8% of patients with breast cancer (BC). We conducted a retrospective review of BC-LMD patients diagnosed at Moffitt Cancer Center from 2011 to 2020, to determine the changing incidence of BC-LMD, factors which are associated with the progression of BC CNS metastasis to BC-LMD, and factors which are associated with OS for patients with BC-LMD. METHODS: Patients with BC and brain/spinal metastatic disease were identified. For those who eventually developed BC-LMD, we used Kaplan-Meier survival curve, log-rank test, univariable, and multivariate Cox proportional hazards regression model to identify factors affecting time from CNS metastasis to BC-LMD and OS. RESULTS: 128 cases of BC-LMD were identified. The proportion of BC-LMD to total BC patients was higher between 2016 and 2020 when compared to 2011-2015. Patients with HR+ or HER2 + BC experienced longer times between CNS metastasis and LMD than patients with triple-negative breast cancer (TNBC). Systemic therapy and whole-brain radiation therapy (WBRT) was associated with prolonged progression to LMD in all patients. Hormone therapy in patients with HR + BC were associated with a delayed BC-CNS metastasis to LMD progression. Lapatinib treatment was associated with a delayed progression to LMD in patients with HER2 + BC. Patients with TNBC-LMD had shorter OS compared to those with HR + and HER2 + BC-LMD. Systemic therapy, intrathecal (IT) therapy, and WBRT was associated with prolonged survival for all patients. Lapatinib and trastuzumab therapy was associated with improved OS in patients with HER2 + BC-LMD. CONCLUSIONS: Increasing rates of BC-LMD provide treatment challenges and opportunities for clinical trials. Prospective trials testing lapatinib and/or similar tyrosine kinase inhibitors, IT therapies, and combination treatments are urgently needed.

[The role of whole brain irradiation nowadays: more or less or different?] / A teljes agyi besugárzás szerepe napjainkban: többet, kevesebbet vagy másként?

In patients with poor performance status (KPS<50), ineligibility for effective systemic treatment and multiple brain metastases (BM) best supportive care is the preferred treatment over whole brain radiotherapy (WBRT). WBRT should be considered for the treatment of non-limited number (>4) brain metastases, depending on the patient's life expectancy, neurological symptoms, size, number and location of brain metastases, indication, type and availability of systemic therapy. In these patients if life expectancy is >4 months without small cell histology and without hippocampal lesions, hippocampal sparing WBRT with or without memantine is recommended. Simultaneous integrated boost for the BM is a logical and supportable concept. Prophylactic cranial irradiation (PCI) is still recommended in small cell lung cancer patients with complete remission. Hippocampal sparing WBRT needs further validation in this indication.

A new updated prognostic index for patients with brain metastases (BMs) treated with palliative whole brain radiotherapy (WBRT) in the era of precision oncology. METASNCore project.

INTRODUCTION: Palliative WBRT is the main treatment for multiple BMs. Recent studies report no benefit in survival after WBRT compared to palliative supportive care in patients (pts) with poor prognosis. A new era of systemic treatment strategies based on targeted therapies are improving the prognosis of patients with BMs. The purpose of this study is to develop a prognostic score in palliative pts with BMs who undergo WBRT in this new setting. METHODS: 239 pts with BMs who received palliative WBRT between 2013-2022 in our center were analyzed retrospectively. The score was designed according to the value of the ß coefficient of each variable with statistical significance in the multivariate model using Cox regression. Once the score was established, a comparison was performed according to Kaplan-Meier and was analyzed by log-rank test. RESULTS: 149 pts (62.3%) were male and median (m) age was 60 years. 139 (58,2%) were lung cancer and 35 (14,6%) breast cancer. All patients received 30Gys in 10 sessions. m overall survival (OS) was 3,74 months (ms). 37 pts (15,5%) had a specific target mutation. We found that 62 pts were in group < 4 points with mOS 6,89 ms (CI 95% 3,18-10,62), 84 in group 4-7 points with mOS 4,01 ms (CI 95% 3,40-4,62) and 92 pts in group > 7 points with mOS 2,72 ms (CI 95% 1,93-3,52) (p < 0,001). CONCLUSIONS: METASNCore items are associated with OS and they could be useful to select palliative pts to receive WBRT. More studies are necessary to corroborate our findings.

Predicting overall survival and prophylactic cranial irradiation benefit in small-cell lung cancer with CT-based deep learning: A retrospective multicenter study.

BACKGROUND AND PURPOSE: To develop a computed tomography (CT)-based deep learning model to predict overall survival (OS) among small-cell lung cancer (SCLC) patients and identify patients who could benefit from prophylactic cranial irradiation (PCI) based on OS signature risk stratification. MATERIALS AND METHODS: This study retrospectively included 556 SCLC patients from three medical centers. The training, internal validation, and external validation cohorts comprised 309, 133, and 114 patients, respectively. The OS signature was built using a unified fully connected neural network. A deep learning model was developed based on the OS signature. Clinical and combined models were developed and compared with a deep learning model. Additionally, the benefits of PCI were evaluated after stratification using an OS signature. RESULTS: Within the internal and external validation cohorts, the deep learning model (concordance index [C-index] 0.745, 0.733) was far superior to the clinical model (C-index: 0.635, 0.630) in predicting OS, but slightly worse than the combined model (C-index: 0.771, 0.770). Additionally, the deep learning model had excellent calibration, clinical usefulness, and improved accuracy in classifying survival outcomes. Remarkably, patients at high risk had a survival benefit from PCI in both the limited and extensive stages (all P < 0.05), whereas no significant association was observed in patients at low risk. CONCLUSIONS: The CT-based deep learning model exhibited promising performance in predicting the OS of SCLC patients. The OS signature may aid in individualized treatment planning to select patients who may benefit from PCI.

DEGRO guideline for personalized radiotherapy of brain metastases and leptomeningeal carcinomatosis in patients with breast cancer.

PURPOSE: The aim of this review was to evaluate the existing evidence for radiotherapy for brain metastases in breast cancer patients and provide recommendations for the use of radiotherapy for brain metastases and leptomeningeal carcinomatosis. MATERIALS AND METHODS: For the current review, a PubMed search was conducted including articles from 01/1985 to 05/2023. The search was performed using the following terms: (brain metastases OR leptomeningeal carcinomatosis) AND (breast cancer OR breast) AND (radiotherapy OR ablative radiotherapy OR radiosurgery OR stereotactic OR radiation). CONCLUSION AND RECOMMENDATIONS: Despite the fact that the biological subtype of breast cancer influences both the occurrence and relapse patterns of breast cancer brain metastases (BCBM), for most scenarios, no specific recommendations regarding radiotherapy can be made based on the existing evidence. For a limited number of BCBM (1-4), stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (SRT) is generally recommended irrespective of molecular subtype and concurrent/planned systemic therapy. In patients with 5-10 oligo-brain metastases, these techniques can also be conditionally recommended. For multiple, especially symptomatic BCBM, whole-brain radiotherapy (WBRT), if possible with hippocampal sparing, is recommended. In cases of multiple asymptomatic BCBM (≥ 5), if SRS/SRT is not feasible or in disseminated brain metastases (> 10), postponing WBRT with early reassessment and reevaluation of local treatment options (8-12 weeks) may be discussed if a HER2/Neu-targeting systemic therapy with significant response rates in the central nervous system (CNS) is being used. In symptomatic leptomeningeal carcinomatosis, local radiotherapy (WBRT or local spinal irradiation) should be performed in addition to systemic therapy. In patients with disseminated leptomeningeal carcinomatosis in good clinical condition and with only limited or stable extra-CNS disease, craniospinal irradiation (CSI) may be considered. Data regarding the toxicity of combining systemic therapies with cranial and spinal radiotherapy are sparse. Therefore, no clear recommendations can be given, and each case should be discussed individually in an interdisciplinary setting.

A large open access dataset of brain metastasis 3D segmentations on MRI with clinical and imaging information.

Resection and whole brain radiotherapy (WBRT) are standard treatments for brain metastases (BM) but are associated with cognitive side effects. Stereotactic radiosurgery (SRS) uses a targeted approach with less side effects than WBRT. SRS requires precise identification and delineation of BM. While artificial intelligence (AI) algorithms have been developed for this, their clinical adoption is limited due to poor model performance in the clinical setting. The limitations of algorithms are often due to the quality of datasets used for training the AI network. The purpose of this study was to create a large, heterogenous, annotated BM dataset for training and validation of AI models. We present a BM dataset of 200 patients with pretreatment T1, T1 post-contrast, T2, and FLAIR MR images. The dataset includes contrast-enhancing and necrotic 3D segmentations on T1 post-contrast and peritumoral edema 3D segmentations on FLAIR. Our dataset contains 975 contrast-enhancing lesions, many of which are sub centimeter, along with clinical and imaging information. We used a streamlined approach to database-building through a PACS-integrated segmentation workflow.

Alterations in hypothalamic-pituitary axis (HPA) hormones 6 months after cranial radiotherapy in adult patients with primary brain tumors outside the HPA region.

BACKGROUND: Cranial radiotherapy is a common treatment for brain tumors, but it can affect the hypothalamic-pituitary (H-P) axis and lead to hormonal disorders. This study aimed to compare serum levels of HPA hormones before and after cranial radiation. MATERIALS AND METHODS: This study involved 27 adult patients who underwent brain tumor resection before the initiation of radiotherapy, and none had metastatic brain tumors. All participants had the HPA within the radiation field, and their tumors were located in brain areas outside from the HPA. Serum levels of HPA hormones were recorded both before and 6 months after cranial radiotherapy. RESULTS: A total of 27 adult patients, comprising 16 (59.3%) males and 11 (40.7%) females, with a mean age of 56.37 ± 11.38 years, were subjected to evaluation. Six months post-radiotherapy, serum levels of GH and TSH exhibited a significant decrease. Prior to radiotherapy, a substantial and direct correlation was observed between TSH and FSH (p = 0.005) as well as LH (p = 0.014). Additionally, a significant and direct relationship was noted between serum FSH and LH (p < 0.001) before radiotherapy. After radiotherapy, a significant and direct correlation persisted between TSH and FSH (p = 0.003) as well as LH (p = 0.005), along with a significant and direct relationship between serum FSH and LH (p < 0.001). Furthermore, a significant and direct association was identified between changes in serum GH levels and FSH (p = 0.04), as well as between serum LH and FSH (p < 0.001). CONCLUSION: Reduced serum levels of HPA hormones are a significant complication of cranial radiotherapy and should be evaluated in follow-up assessments.

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

OBJECTIVE: To evaluate the therapeutic advantage of G-CSF to whole brain radiotherapy (WBRT) in combination with immunotherapy as a first-line treatment for non-small cell lung cancer (NSCLC) brain metastases (BMs). METHODS: In this retrospective study, 117 patients (37 in G-CSF group and 80 in no G-CSF group) who underwent first-line WBRT combined with immunotherapy were enrolled. Their survival, intracranial response, BM-related symptoms and toxicity were evaluated. RESULTS: The overall survival (OS) of patients in G-CSF group was significantly improved compared to patients no G-CSF group (median time: 14.8 vs 10.2 months; HR: 0.61, 95 % CI: 0.38-0.97, p = 0.035). However, there were no significant differences in intracranial responses between the two groups (p > 0.05). The G-CSF group exhibited a significantly higher rate of relief from BM-related symptoms compared to the no G-CSF group (91.7 % vs 59.5 %, p = 0.037). Cox proportional hazards regression analyses indicated that after-treatment ALC > 0.9 × 10^9/L (HR 0.57, 95 % CI 0.32-0.99, p = 0.046) and Hb > 110 g/dL (HR 0.41, 95 % CI 0.24-0.71, p = 0.001) were significant potential factors associated with extended OS. The addition of G-CSF was well tolerated and effectively reduced the incidence of neutropenia (0 % vs 5.0 %, p = 0.17). CONCLUSION: Integrating G-CSF with WBRT and immunotherapy as a first-line treatment for NSCLC-BMs has exhibited significant efficacy and favorable tolerability.

Non-Faradaic optoelectrodes for safe electrical neuromodulation.

Nanoscale optoelectrodes hold the potential to stimulate optically individual neurons and intracellular organelles, a challenge that demands both a high-density of photoelectron storage and significant charge injection. Here, we report that zinc porphyrin, commonly used in dye-sensitized solar cells, can be self-assembled into nanorods and then coated by TiO2. The J-aggregated zinc porphyrin array enables long-range exciton diffusion and allows for fast electron transfer into TiO2. The formation of TiO2(e-) attracts positive charges around the neuron membrane, contributing to the induction of action potentials. Far-field cranial irradiation of the motor cortex using a 670 nm laser or an 850 nm femtosecond laser can modulate local neuronal firing and trigger motor responses in the hind limb of mice. The pulsed photoelectrical stimulation of neurons in the subthalamic nucleus alleviates parkinsonian symptoms in mice, improving abnormal stepping and enhancing the activity of dopaminergic neurons. Our results suggest injectable nanoscopic optoelectrodes for optical neuromodulation with high efficiency and negligible side effects.

Effects of X-ray cranial irradiation on metabolomics and intestinal flora in mice.

Cranial radiotherapy is an important treatment for intracranial and head and neck tumors. To investigate the effects of cranial irradiation (C-irradiation) on gut microbiota and metabolomic profile, the feces, plasma and cerebral cortex were isolated after exposing mice to cranial X-ray irradiation at a dose rate of 2.33 Gy/min (5 Gy/d for 4 d consecutively). The gut microorganisms and metabolites were detected by 16 S rRNA gene sequencing method and LC-MS method, respectively. We found that compared with sham group, the gut microbiota composition changed at 2 W and 4 W after C-irradiation at the genus level. The fecal metabolomics showed that compared with Sham group, 44 and 66 differential metabolites were found to be annotated into metabolism pathways at 2 W and 4 W after C-irradiation, which were significantly enriched in the arginine and proline metabolism. Metabolome analysis of serum and cerebral cortex showed that, at 4 W after C-irradiation, the expression pattern of metabolites in serum samples of mice was similar to that of sham group, and the cerebral cortex metabolites of the two groups were completely separated. KEGG functional analysis showed that serum and brain tissue differential metabolites were respectively enriched in tryptophan metabolism, and arginine proline metabolism. The correlation analysis showed that the changes of gut microbiota genera were significantly correlated with the changes of metabolism, especially Helicobacter, which was significantly correlated with many different metabolites at 4 W after C-irradiation. These data suggested that C-irradiation could affect the gut microbiota and metabolism profile, even at relatively long times after C-irradiation.

Craniospinal irradiation for CNS leukemia: rates of response and durability of CNS control.

PURPOSE: Management of CNS involvement in leukemia may include craniospinal irradiation (CSI), though data on CSI efficacy are limited. METHODS: We retrospectively reviewed leukemia patients who underwent CSI at our institution between 2009 and 2021 for CNS involvement. CNS local recurrence (CNS-LR), any recurrence, progression-free survival (PFS), CNS PFS, and overall survival (OS) were estimated. RESULTS: Of thirty-nine eligible patients treated with CSI, most were male (59%) and treated as young adults (median 31 years). The median dose was 18 Gy to the brain and 12 Gy to the spine. Twenty-five (64%) patients received CSI immediately prior to allogeneic hematopoietic cell transplant, of which 21 (84%) underwent total body irradiation conditioning (median 12 Gy). Among 15 patients with CSF-positive disease immediately prior to CSI, all 14 assessed patients had pathologic clearance of blasts (CNS-response rate 100%) at a median of 23 days from CSI start. With a median follow-up of 48 months among survivors, 2-year PFS and OS were 32% (95% CI 18-48%) and 43% (95% CI 27-58%), respectively. Only 5 CNS relapses were noted (2-year CNS-LR 14% (95% CI 5-28%)), which occurred either concurrently or after a systemic relapse. Only systemic relapse after CSI was associated with higher risk of CNS-LR on univariate analysis. No grade 3 or higher acute toxicity was seen during CSI. CONCLUSION: CSI is a well-tolerated and effective treatment option for patients with CNS leukemia. Control of systemic disease after CSI may be important for CNS local control. CNS recurrence may reflect reseeding from the systemic space.

Hippocampal region avoidance in whole brain radiotherapy in brain metastases: For all or for some? A real-world feasibility report.

PURPOSE: Hippocampal sparing whole-brain radiotherapy (HS-WBRT) showed significantly lower long-term side effects compared to standard WBRT. Aim of this study is to describe a HS-WBRT real-world monoinstitutional experience within a retrospective cohort. METHODS: Patients who completed HS-WBRT course, with Karnofsky Performance Status ⩾ 60 and radiological diagnosis of brain metastases (BMs) were enrolled. Treatment was performed using helical Tomotherapy scheduled in 30 Gy in 10 or 12 fractions or 25 Gy in 10 fractions. Oncological outcomes were clinically and radiologically assessed every three months. Toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events 4.3. RESULTS: One hundred and nineteen patients from 2016 to 2020 met inclusion criteria; after a median follow-up of 18 months, 29 patients were alive; 6- and 12-months overall survival rates were 66% and 41%, respectively. HS-WBRT response was assessed for 72 patients. Median time to any progression and intracranial failure (IF) was 4.5 and 13.7 months, respectively. The 6- and 12-month IF rates were 85% and 57%. Among 40 patients (34%) who experienced IF, 17 (42%) were oligometastatic, 23 (58%) polymetastatic and 15/40 developed IF within the hippocampi avoidance zone. No grade (G) ⩾ 2 acute toxicities were reported and one G2 (dizziness) late toxicity was described. CONCLUSIONS: HS-WBRT is well tolerated, and despite the hippocampal sparing region, the oncological control is satisfying. Further investigation is warranted to find patients who could most benefit from a HS-WBRT approach.

Coordination of anti-CTLA-4 with whole-brain radiation therapy decreases tumor burden during treatment in a novel syngeneic model of lung cancer brain metastasis.

Lung cancer is the most common primary tumor to metastasize to the brain. Although advances in lung cancer therapy have increased rates of survival over the past few decades, control and treatment of lung cancer brain metastasis remains an urgent clinical need. Herein, we examine the temporal coordination of α-CTLA-4 administration in combination with whole-brain radiation therapy in a syngeneic preclinical model of lung cancer brain metastasis in both C57Bl/6 and athymic nude mice. Brain tumor burden, survival, and weight loss were monitored. Immunotherapy administration 24 h prior to irradiation resulted in increased brain tumor burden, while administration of immunotherapy 12 h after radiation decreased tumor burden. Neither of the treatments affected survival outcomes or weight loss due to brain tumor recurrence. These findings suggest that the coordination of α-CTLA-4 administration in addition to whole-brain radiation therapy may be a viable strategy for reduction of tumor burden for the management of lung cancer brain metastasis.

Radiotherapy in Preclinical Models of Brain Metastases: A Review and Recommendations for Future Studies.

Brain metastases (BMs) frequently occur in primary tumors such as lung cancer, breast cancer, and melanoma, and are associated with notably short natural survival. In addition to surgical interventions, chemotherapy, targeted therapy, and immunotherapy, radiotherapy (RT) is a crucial treatment for BM and encompasses whole-brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS). Validating the efficacy and safety of treatment regimens through preclinical models is imperative for successful translation to clinical application. This not only advances fundamental research but also forms the theoretical foundation for clinical study. This review, grounded in animal models of brain metastases (AM-BM), explores the theoretical underpinnings and practical applications of radiotherapy in combination with chemotherapy, targeted therapy, immunotherapy, and emerging technologies such as nanomaterials and oxygen-containing microbubbles. Initially, we provided a concise overview of the establishment of AM-BMs. Subsequently, we summarize key RT parameters (RT mode, dose, fraction, dose rate) and their corresponding effects in AM-BMs. Finally, we present a comprehensive analysis of the current research status and future directions for combination therapy based on RT. In summary, there is presently no standardized regimen for AM-BM treatment involving RT. Further research is essential to deepen our understanding of the relationships between various parameters and their respective effects.

Construction of brain metastasis prediction model in limited stage small cell lung cancer patients without prophylactic cranial irradiation.

INTRODUCTION: Small cell lung cancer (SCLC) is a highly aggressive lung cancer variant known for its elevated risk of brain metastases (BM). While earlier meta-analyses supported the use of prophylactic cranial irradiation (PCI) to reduce BM incidence and enhance overall survival, modern MRI capabilities raise questions about PCI's universal benefit for limited-stage SCLC (LS-SCLC) patients. As a response, we have created a predictive model for BM, aiming to identify low-risk individuals who may not require PCI. METHODS: A total of 194 LS-SCLC patients without PCI treated between 2009 and 2021 were included. We conducted both univariate and multivariate analyses to pinpoint the factors associated with the development of BM. A nomogram for predicting the 2- and 3-year probabilities of BM was then constructed. RESULTS: Univariate and multivariate analyses revealed several significant independent risk factors for the development of BM. These factors include TNM stage, the number of chemotherapy (ChT) cycles, Ki-67 expression level, pretreatment serum lactate dehydrogenase (LDH) levels, and haemoglobin (HGB) levels. These findings underscore their respective roles as independent predictors of BM. Based on the results of the final multivariable analysis, a nomogram model was created. In the training cohort, the nomogram yielded an area under the receiver operating characteristic curve (AUC) of 0.870 at 2 years and 0.828 at 3 years. In the validation cohort, the AUC values were 0.897 at 2 years and 0.789 at 3 years. The calibration curve demonstrated good agreement between the predicted and observed probabilities of BM. CONCLUSIONS: A novel nomogram has been developed to forecast the likelihood of BM in patients diagnosed with LS-SCLC. This tool holds the potential to assist healthcare professionals in formulating more informed and tailored treatment plans.