Sinonasal Malignancy Following Cranial Irradiation: A Scoping Review and Case Report of Sinonasal Teratocarcinosarcoma.

Background Radiation therapy is a mainstay of treatment for brain tumors, but delayed complications include secondary malignancy which may occur months to years after treatment completion. Methods We reviewed the medical records of a 41-year-old female treated with 60 Gy of radiation for a recurrent astrocytoma, who 6 years later developed a locally advanced sinonasal teratocarcinosarcoma. We searched MEDLINE, Embase, and Web of Science to conduct a scoping review of biopsy-proven sinonasal malignancy in patients who previously received cranial irradiation for a brain tumor. Results To our knowledge, this is the first report of a patient to present with a sinonasal teratocarcinosarcoma after receiving irradiation for a brain tumor. Our scoping review of 1,907 studies produced 14 similar cases of secondary sinonasal malignancy. Median age of primary cancer diagnosis was 39.5 years old (standard deviation [SD]: 21.9), and median radiation dose was 54 Gy (SD: 20.3). Median latency time between the primary cancer and secondary sinonasal cancer was 9.5 years (SD: 5.8). Olfactory neuroblastoma was the most common sinonasal cancer ( n = 4). Fifty percent of patients died from their sinonasal cancer within 1.5 years. Conclusion Patients who receive radiation exposure to the sinonasal region for treatment of a primary brain tumor, including low doses or scatter radiation, may be at risk of a secondary sinonasal malignancy later in life. Physicians who monitor at-risk patients must be vigilant of symptoms which may suggest sinonasal malignancy, and surveillance should include radiographic review with careful monitoring for a secondary malignancy throughout the entire irradiated field.

Safety and Feasibility of Hippocampal Sparing Cranial Radiation in Pediatric and Adolescent Acute Lymphoblastic Leukemia Patients: A Prospective Study.

Introduction Acute lymphoblastic leukemia (ALL) constitutes a significant portion of pediatric malignancies, with central nervous system (CNS) relapse posing a considerable threat to patient outcomes. While cranial radiation therapy (CRT) has been utilized to mitigate CNS relapse, it is associated with neurocognitive (NC) side effects. This study explores the feasibility and safety of using volumetric arc therapy (VMAT) with hippocampal sparing (HS) during cranial radiation therapy for ALL patients, aiming to reduce these side effects. Methodology This prospective observational study included pediatric and young adult patients with ALL who were in remission. HS was achieved using VMAT, and NC assessments were performed at baseline, six months, one year, and, to a limited extent, four years posttreatment. Results VMAT enabled precise hippocampal-sparing CRT with minimal dose to the hippocampus. Dosimetric analysis revealed that patients receiving 18 Gy had mean doses to planning target volume (PTV) and bilateral hippocampus of 18.9 and 9 Gy, respectively. Those receiving 12 Gy had corresponding doses of 13.3 and 7 Gy, respectively. Conformity and homogeneity indices were 0.9 and 0.1, and no brain relapses were observed among the patients in this study. NC assessments demonstrated no decline in intelligence quotient (IQ) scores over time, while only a subset of patients could be assessed at the four-year mark; telephone interviews suggested no significant cognitive decline. Conclusions This study highlights the potential of VMAT with HS as a promising approach to CRT for ALL patients in reducing the risk of NC side effects. The absence of brain relapses and preservation of NC function are encouraging findings, though larger studies are necessary to establish conclusive evidence.

Prevention of Brain Metastases: A New Frontier.

This review discusses the topic of prevention of brain metastases from the most frequent solid tumor types, i.e., lung cancer, breast cancer and melanoma. Within each tumor type, the risk of brain metastasis is related to disease status and molecular subtype (i.e., EGFR-mutant non-small cell lung cancer, HER2-positive and triple-negative breast cancer, BRAF and NRAF-mutant melanoma). Prophylactic cranial irradiation is the standard of care in patients in small cell lung cancer responsive to chemotherapy but at the price of late neurocognitive decline. More recently, several molecular agents with the capability to target molecular alterations driving tumor growth have proven as effective in the prevention of secondary relapse into the brain in clinical trials. This is the case for EGFR-mutant or ALK-rearranged non-small cell lung cancer inhibitors, tucatinib and trastuzumab-deruxtecan for HER2-positive breast cancer and BRAF inhibitors for melanoma. The need for screening with an MRI in asymptomatic patients at risk of brain metastases is emphasized.

Surgery and Stereotactic Radiotherapy for Stage I Small-Cell Lung Carcinoma: A 25-Year Experience.

OBJECTIVES: Small-cell lung carcinoma (SCLC) is usually a wide-spread, highly-lethal malignancy but occasionally presents as localized, limited stage cancer amenable to local treatment. We reviewed our experience using surgery or stereotactic body radiotherapy (SBRT) to assess safety, survival rates and treatment toxicity in clinical stage I SCLC patients. MATERIALS AND METHODS: Electronic medical records of patients with clinical stage I lymph node-negative SCLC who underwent surgical resection or SBRT between 1996 and 2021 were retrospectively reviewed. A multivariable Cox Proportional Hazards model was constructed. RESULTS: Of 96 patients meeting inclusion criteria, 77 underwent resection and 19 underwent SBRT. Surgical patients were younger (mean 68.4 ± 9.2 years surgery versus 74.3 ± 6.6 years SBRT, P = .005) and had better pulmonary function (81.5 ± 19.6 FEV1% of predicted surgery versus 44.0 ± 20.9% SBRT, P < .001). SBRT patients had significantly more comorbidities. For both cohorts, 59 tumors were pure SCLC and 37 were mixed SCLC/NSCLC histology. Median survivals were 21 months versus 31 months for SBRT and surgery patients respectively (P = .07). There were no treatment-related mortalities. Mean length of hospital stay for surgical patients was 5.4 ± 5.7 days. Survival was longer in lymph node-negative surgery patients (median 48 months node-negative versus 19 months node-positive, P = .04). For node-negative-surgery patients, the estimated 2- and 5-year survival rates are 60% and 48%. CONCLUSIONS: Our single-institutional experience over 25 years demonstrates that local treatment with surgery or SBRT for clinical stage I SCLC is safe and effective, with survivals lower than similar stage non-small-cell carcinoma patients. However, our results compare favorably with prior small-cell surgical series and far better than reported results of chemoradiotherapy for similar stage patients, thereby validating current recommendations for employing surgery or SBRT for stage I SCLC.

SCF/C-kit drives spermatogenesis disorder induced by abscopal effects of cranial irradiation in mice.

Cranial radiotherapy is a major treatment for leukemia and brain tumors. Our previous study found abscopal effects of cranial irradiation could cause spermatogenesis disorder in mice. However, the exact mechanisms are not yet fully understood. In the study, adult male C57BL/6 mice were administrated with 20 Gy X-ray cranial irradiation (5 Gy per day for 4 days consecutively) and sacrificed at 1, 2 and 4 weeks. Tandem Mass Tag (TMT) quantitative proteomics of testis was combined with bioinformatics analysis to identify key molecules and signal pathways related to spermatogenesis at 4 weeks after cranial irradiation. GO analysis showed that spermatogenesis was closely related to oxidative stress and inflammation. Severe oxidative stress occurred in testis, serum and brain, while serious inflammation also occurred in testis and serum. Additionally, the sex hormones related to hypothalamic-pituitary-gonadal (HPG) axis were disrupted. PI3K/Akt pathway was activated in testis, which upstream molecule SCF/C-Kit was significantly elevated. Furthermore, the proliferation and differentiation ability of spermatogonial stem cells (SSCs) were altered. These findings suggest that cranial irradiation can cause spermatogenesis disorder through brain-blood-testicular cascade oxidative stress, inflammation and the secretory dysfunction of HPG axis, and SCF/C-kit drive this process through activating PI3K/Akt pathway.

Incidence of hippocampal and perihippocampal brain metastases and impact on hippocampal-avoiding radiotherapy: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: In patients requiring prophylactic cranial irradiation (PCI) or whole-brain radiotherapy (WBRT) for brain metastases (BMs), hippocampal avoidance (HA) has been shown to preserve neurocognitive function and quality of life. Here, we aim to estimate the incidence of hippocampal and perihippocampal BMs and the subsequent risk of local undertreatment in patients undergoing hippocampal sparing radiotherapy. MATERIALS AND METHODS: MEDLINE, Embase, and Scopus were searched with the terms "Hippocampus", "Brain Neoplasms", and related terms. Trials reporting on the incidence of hippocampal and/or perihippocampal BMs or hippocampal failure rate after PCI or WBRT were included. RESULTS: Forty records were included, encompassing a total of 5,374 patients with over 32,570 BMs. Most trials employed a 5 mm margin to define the HA zone. In trials reporting on BM incidence, 4.4 % (range 0 - 27 %) and 9.2 % (3 - 41 %) of patients had hippocampal and perihippocampal BMs, respectively. The most common risk factor for hippocampal BMs was the total number of BMs. The reported failure rate within the HA zone after HA-PCI or HA-WBRT was 4.5 % (0 - 13 %), salvageable with radiosurgery in most cases. SCLC histology was not associated with a higher risk of hippocampal failure (OR = 2.49; p = 0.23). In trials comparing with a conventional (non-HA) PCI or WBRT group, HA did not increase the hippocampal failure rate (OR = 1.90; p = 0.17). CONCLUSION: The overall incidence of hippocampal and perihippocampal BMs is considerably low, with a subsequent low risk of local undertreatment following HA-PCI or HA-WBRT. In patients without involvement, the hippocampus should be spared to preserve neurocognitive function and quality of life.

Predicting the risk of neurocognitive decline after brain irradiation in adult patients with a primary brain tumor.

BACKGROUND: Deterioration of neurocognitive function in adult patients with a primary brain tumor is the most concerning side effect of radiotherapy. This study was aimed to develop and evaluate Normal-Tissue Complication Probability (NTCP) models using clinical and dose-volume measures for 6-month, 1-year and 2-year Neurocognitive Decline (ND) post-radiotherapy. METHODS: A total of 219 patients with a primary brain tumor treated with radical photon and/or proton radiotherapy (RT) between 2019 and 2022 were included. Controlled Oral Word Association (COWA) test, Hopkins Verbal Learning Test-Revised (HVLTR) and Trail Making Test (TMT) were used to objectively measure ND. A comprehensive set of potential clinical and dose-volume measures on several brain structures were considered for statistical modelling. Clinical, dose-volume and combined models were constructed and internally tested in terms of discrimination (Area Under the Curve, AUC), calibration (Mean Absolute Error, MAE) and net benefit. RESULTS: 50%, 44.5% and 42.7% of the patients developed ND at 6-month, 1-year and 2-year timepoints, respectively. Following predictors were included in the combined model for 6-month ND: age at radiotherapy>56 years (OR=5.71), overweight (OR=0.49), obesity (OR=0.35), chemotherapy (OR=2.23), brain V20Gy≥20% (OR=3.53), brainstem volume≥26cc (OR=0.39) and hypothalamus volume≥0.5cc (OR=0.4). Decision curve analysis showed that the combined models had the highest net benefits at 6-month (AUC=0.79, MAE=0.021), 1-year (AUC=0.72, MAE=0.027) and 2-year (AUC=0.69, MAE=0.038) timepoints. CONCLUSION: The proposed NTCP models use easy-to-obtain predictors to identify patients at high-risk of ND after brain RT. These models can potentially provide a base for RT-related decisions and post-therapy neurocognitive rehabilitation interventions.

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.

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.

Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia in Children: A Retrospective Cohort Study at a Pediatric Oncology Center.

Background and objective Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL Ph+) is quite rare among pediatric patients. Its management has undergone significant changes in the past few years, leading to some variability in how it is approached. At the Portuguese Oncology Institute of Porto (IPOP), a tertiary oncological center, the standard of care has been aligned with the guidelines proposed by the European intergroup study of post-induction treatment of ALL Ph+ (EsPhALL). In this study, we aimed to examine the experience and outcomes related to the treatment of pediatric patients with ALL Ph+ at IPOP. Methods This retrospective cohort study involved pediatric patients diagnosed with ALL Ph+ at IPOP between January 2008 and December 2022 and analyzed their outcomes. Results A total of 14 patients were included. IKFZ1 was altered in five patients (out of nine in whom it was searched). Five patients were treated according to EsPhALL 2004, which involved starting imatinib later in a discontinuous manner [resulting in both five-year overall survival (OS) and progression-free survival (PFS) of 60%]. The EsPhALL 2010 (preconizing a continuous imatinib regimen instead) was employed in three patients, with a five-year OS and PFS of 66.7%. All children mentioned above received cranial irradiation therapy (CRT). Finally, six were treated according to the EsPhALL 2015, which stopped including CRT in its backbone. The five-year OS was 100%, whereas every patient progressed with an increase in BCR::ABL1 levels greater than 1-log. Moreover, until 2015, all patients had been recommended to undergo allogeneic hematopoietic stem cell transplantation (alloHSCT). However, since 2015, alloHSCT has been exclusively reserved for relapsed/refractory (R/R) disease or poor responders with positive measurable residual disease (MRD). In total, alloHSCT was performed in nine patients. Conclusions Although initially associated with a poor prognosis, the ALL Ph+ paradigm is drastically shifting. Further studies will hopefully clarify the outcomes in this population and help understand the role of central nervous system (CNS) prophylaxis, alloHSCT, and MRD quantification.

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.

Re-examining prophylactic cranial irradiation in small cell lung cancer: a systematic review and meta-analysis.

Background: Patients with small cell lung cancer (SCLC) are at high risk for brain metastases. Prophylactic cranial irradiation (PCI) is recommended in this population to reduce the incidence of brain metastases and prolong survival. We aimed to assesses the efficacy of PCI in this population in the era of routine brain imaging. To our knowledge, this is the first systematic review and meta-analysis to examine the use among patients who were radiographically confirmed not to have brain metastases after completion of first-line therapy. Methods: In this systematic review and meta-analysis, cohort studies and controlled trials reporting on the use of PCI for patients SCLC were identified in EMBASE, MEDLINE, CENTRAL, and grey literature sources. The literature search was conducted on November 12, 2023. Summary data were extracted. Random-effects meta-analyses pooled hazard ratios (HR) for the primary outcome of overall survival between PCI and no intervention groups. This study is registered with the Open Science Framework, DOI:10.17605/OSF.IO/BC359, and PROSPERO, CRD42021249466. Findings: Of 4318 identified records, 223 were eligible for inclusion. 109 reported on overall survival in formats amenable to meta-analysis; PCI was associated with longer survival in all patients with SCLC (HR 0.59; 95% CI, 0.55-0.63; p < 0.001; n = 56,770 patients), patients with limited stage disease (HR 0.60; 95% CI, 0.55-0.65; p < 0.001; n = 78 studies; n = 27,137 patients), and patients with extensive stage disease (HR 0.59; 95% CI, 0.51-0.70; p < 0.001; n = 28 studies; n = 26,467 patients). Between-study heterogeneity was significant when pooled amongst all studies (I2 = 73.6%; 95% CI 68.4%-77.9%). Subgroup analysis did not reveal sources of heterogeneity. In a subgroup analysis on studies that used magnetic resonance imaging to exclude presence of brain metastases at restaging among all patients, overall survival did not differ significantly between patients who did or did not receive PCI (HR 0.74; 95% CI, 0.52-1.05; p = 0.08; n = 9 studies; n = 1384 patients). Interpretation: Our findings suggested that administration of PCI is associated with a survival benefit, but not when considering studies that radiographically confirmed absence of brain metastases, suggesting that the survival benefit conferred by PCI might be therapeutic rather than prophylactic. Funding: No funding.

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.

Rupture of a flow aneurysm secondary to spontaneous extracranial to intracranial revascularisation in the posterior fossa following radiation-induced vasculopathy for cerebellar tumour.

Paediatric patients receiving cranial irradiation therapy for brain tumours are at increased risk of cerebrovascular complications. Radiation-induced moyamoya syndrome (MMS) is a well-recognised complication of this. We present a case of an 8-year-old boy with a history of medulloblastoma, who underwent surgical excision followed by post-operative adjuvant oncological treatment. Six years later, he developed cerebellar/intraventricular haemorrhage. He underwent an emergency external ventricular drain (EVD) insertion followed by posterior fossa suboccipital craniotomy. On dural opening, an abnormal vessel was visualised on the surface of the right cerebellar hemisphere, which was not disturbed. No obvious abnormalities were identified intra-operatively. Cerebral catheter angiography confirmed the presence of a right-sided occipital artery (OA) to posterior inferior cerebellar artery (PICA) extracranial to intracranial (EC-IC) bypass with a zone of the distal PICA territory supplied by this EC-IC bypass. A presumed flow aneurysm originated from the bypass in the distal PICA, identified as cause for the haemorrhage. We highlight a rare cause for intracranial haemorrhage in this cohort of patients. Children who have undergone radiotherapy may have exquisitely sensitive cerebral vasculature and need careful vigilance and evaluation for vasculopathic complications following spontaneous haemorrhage.

Cranial radiation therapy with hippocampus avoidance in lung cancer treatment: systematic review and meta-analysis.

Background: The role of cranial radiation therapy with hippocampus avoidance (HA-CRT) in neurocognitive function (NCF), brain metastasis (BM), and overall survival (OS) in lung cancer remains unclear. Methods: A meta-analysis was conducted to evaluate the impact of HA-CRT in lung cancer. Data from studies on hippocampal-avoidance prophylactic cranial irradiation (HA-PCI) and whole brain radiotherapy (HA-WBRT) were pooled. Results: A total of 14 studies, including 5 randomized controlled trials, were included. The focus of NCF was mainly via the Hopkins Verbal Learning Test-Revised or the Free and Cued Selective Reminding Test. At 6 months post-radiotherapy, the pooled proportion of participants with decline in the performance of total recall, delayed recall, and discrimination in neurocognitive tests were 0.22 (95% CI 0.15, 0.29), 0.20 (95% CI 0.13, 0.27), and 0.14 (95% CI 0.05, 0.24) respectively. After 12 months, the proportion were 0.16 (95% CI 0.08, 0.23), 0.10 (95% CI 0.04, 0.16), and 0.04 (95% CI 0, 0.09) respectively. For HA zone relapse, the RR of HA-CRT versus CRT was 2.72 (95% CI 0.53, 13.87), and for 2-year BM, it was 1.20 (95% CI 0.82, 1.75). Regarding HA-PCI in SCLC, the 1-year BM rate was 0.12 (95% CI 0.07, 0.17), and the 2-year BM rate was 0.20 (95% CI 0.16, 0.25). For HA-WBRT in NSCLC with BM, the 2-year intracranial progression rate was 0.38 (95% CI 0.13, 0.62). There was no significant difference in OS between HA-CRT and CRT. Conclusions: HA-CRT appears to be safe in lung cancer, but it may not outperform conventional CRT. Larger RCTs comparing HA-CRT and CRT are warranted. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022360890, identifier CRD42022360890.

Radiotherapy for extensive-stage small-cell lung cancer in the immunotherapy era.

Currently, chemoimmunotherapy is the first-line treatment for extensive-stage small-cell lung cancer (ES-SCLC). However, only 0.8%-2.5% of the patients presented complete response after chemoimmunotherapy. Considering that ES-SCLC is highly sensitive to radiotherapy, the addition of radiotherapy after first-line treatment for ES-SCLC could further improve local control, which may be beneficial for patients' survival. Prior studies have shown that consolidative thoracic radiotherapy (cTRT) can decrease disease progression and improve overall survival in patients with ES-SCLC who respond well to chemotherapy. However, the efficacy and safety of cTRT in the immunotherapy era remain unclear owing to a lack of prospective studies. Prophylactic cranial irradiation (PCI) has been shown to decrease brain metastasis (BM) and prolong survival in patients with limited-stage SCLC in previous reports. However, according to current guidelines, PCI is not commonly recommended for ES-SCLC. Immunotherapy has the potential to reduce the incidence of BM. Whether PCI can be replaced with regular magnetic resonance imaging surveillance for ES-SCLC in the era of immunotherapy remains controversial. Whole brain radiation therapy (WBRT) is the standard treatment for BM in SCLC patients. Stereotactic radiosurgery (SRS) has shown promise in the treatment of limited BM. Considering the potential of immunotherapy to decrease BM, it is controversial whether SRS can replace WBRT for limited BM in the immunotherapy era. Additionally, with the addition of immunotherapy, the role of palliative radiotherapy may be weakened in patients with asymptomatic metastatic lesions. However, it is still indispensable and urgent for patients with obvious symptoms of metastatic disease, such as spinal cord compression, superior vena cava syndrome, lobar obstruction, and weight-bearing metastases, which may critically damage the quality of life and prognosis. To improve the outcome of ES-SCLC, we discuss the feasibility of radiotherapy, including cTRT, PCI, WBRT/SRS, and palliative radiotherapy with immunotherapy based on existing evidence, which may offer specific prospects for further randomized trials and clinical applications.

Cerebral Radiation-Induced Vasculopathy Mimicking Primary Central Nervous System Vasculitis.

Cranial irradiation is one of the main treatment modalities for tumors of the CNS. However, it can lead to significant damage to the treated region. Among the late complications of radiation therapy to the brain is vasculopathy of the small and/or large arteries. In this article, we report a case of CNS radiation-induced vasculopathy presenting 30 years after cranial irradiation and mimicking primary CNS vasculitis. The present case illustrates the importance of monitoring and carefully evaluating delayed side effects of radiotherapy as well as emphasizes the importance of obtaining a detailed history of any patient presenting with sudden unexplained symptoms. If a complete proper history of the patient's past medical diagnoses and procedures was taken, medical professionals would not have needed to conduct extensive investigations and implement treatment plans for a less likely diagnosis, in this case, aggressive treatment of a possible primary CNS vasculitis with high-dose steroids. Therefore, it is imperative to raise the possibility of radiation-induced vasculopathy after excluding all possible causes of deterioration in patients with a history of cranial radiation therapy.

Prophylactic cranial irradiation effect on survival in patients with small cell lung cancer: a comprehensive systematic review and meta-analysis.

OBJECTIVE: Prophylactic cranial irradiation (PCI) is a companion treatment option for small cell lung cancer (SCLC) patients. However, its efficacy and associated risk factors have not been clearly defined. In this study, the authors aimed to systematically assess the effectiveness and role of PCI in the treatment plan of SCLC. METHODS: The PubMed, Scopus, Web of Science, and Cochrane databases were searched using the following key terms and their equivalents: "brain," "radiotherapy," "metastases," "prophylactic," and "small cell lung cancer." Studies comparing overall survival (OS), progression-free survival (PFS), brain metastasis-free survival (BMFS), and incidence of brain metastases between patients receiving PCI and those not receiving it were considered eligible. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies-of Interventions (ROBINS-I) tool. Meta-analysis was conducted on the mentioned outcomes with subgrouping based on different factors. RESULTS: The authors identified 74 studies published between 1983 and 2022 with 31,551 SCLC patients, of whom 26.7% received PCI. The studies were a mix of prospective randomized and retrospective observational studies. Patients with limited-stage disease receiving PCI had better OS, PFS, and BMFS than those not receiving PCI. Patients receiving PCI also had significantly longer OS times and developed brain metastases significantly later. However, findings regarding extensive-stage SCLC were not as promising. CONCLUSIONS: PCI is an effective option for limited-stage SCLC patients. It improves OS and PFS, delays brain metastases, and reduces the incidence of brain metastases. However, it might not benefit patients with extensive-stage SCLC under adequate follow-up with MRI surveillance. Finally, the heterogeneity of the included studies and publication bias were the main limitations of this study.

The incorporation of cognitive-sparing techniques into prophylactic cranial irradiation in the management of small cell lung cancer.

The use of prophylactic cranial irradiation (PCI) remains an important component in the management of small cell lung cancer (SCLC). This is due to the high rates of subclinical brain metastases at the time of diagnosis. Following a response to initial treatment, PCI historically has been associated with improvements in overall survival and decreased development of brain metastases in patients with limited stage (LS-SCLC) and extensive stage (ES-SCLC) SCLC. However, PCI is commonly withheld in these settings in favor of observation, largely due to its association with cognitive sequelae following treatment. While randomized data has demonstrated that in patients with ES-SCLC, PCI may be withheld in favor of close MRI surveillance without a detriment in overall survival or cognitive functioning, these patients did not undergo formal neuropsychological assessments. In recent years, cognitive sparing techniques incorporated into whole brain radiation therapy and PCI, such as the addition of memantine and hippocampal avoidance, have demonstrated significant improvements in cognitive outcomes. As the overall survival in patients with SCLC continues to improve due to the incorporation of novel systemic therapies (e.g., immune checkpoint inhibitors), the role of PCI and maximizing quality of life remains a highly relevant topic. This article reviews the role of PCI and cognitive-sparing techniques in the management of SCLC.

Self-Reported Cognitive Function and Quality of Life in Patients With SCLC in the Hippocampal Avoidance Prophylactic Cranial Irradiation Versus Prophylactic Cranial Irradiation Randomized Phase 3 Trial (NCT01780675).

Introduction: In the randomized controlled trial in patients with SCLC comparing standard prophylactic cranial irradiation (PCI) with hippocampal avoidance PCI (HA-PCI), we did not observe beneficial effects of HA-PCI on tested cognition. Here, we report findings on self-reported cognitive functioning (SRCF) and quality of life (QoL). Methods: Patients with SCLC were randomized to receive PCI with or without HA (NCT01780675) and assessed at baseline (82 HA-PCI and 79 PCI patients) and at 4, 8, 12, 18, and 24 months of follow-up, using the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and EORTC QLQ-brain cancer module (BN20). SRCF was assessed with the cognitive functioning scale of the EORTC QLQ-C30 and the Medical Outcomes Study questionnaire. A change of 10 points was used for minimal clinically important differences. Percentages of patients classified with having improved, stable, or deteriorated SRCF were compared between groups using chi-square tests. Changes in mean scores were analyzed using linear mixed models. Results: There was no significant difference in the percentage of patients with deteriorated, stable, or improved SRCF between the treatment arms. Depending on the evaluated time point, 31% to 46% and 29% to 43% of patients in the HA-PCI and PCI arm, respectively, reported a deteriorated SRCF on the basis of the EORTC QLQ-C30 and Medical Outcomes Study. QoL outcomes were not significantly different between the study arms, except for physical functioning at 12 months (p = 0.019) and motor dysfunction at 24 months (p = 0.020). Conclusions: Our trial did not find beneficial effects of HA-PCI over PCI on SRCF and QoL. The cognitive benefit of sparing the hippocampus in the context of PCI is still a subject of debate.