Prognostic significance of hemorrhage requiring embolization in the setting of previously treated head and neck squamous cell carcinoma: Systematic review and retrospective cohort.

BACKGROUND: The management of acute hemorrhage in patients with previously treated head and neck squamous cell carcinoma (HNSCC) is challenging due to the lack of substantial evidence to guide clinical decision making. METHODS: A systematic review and retrospective chart review were performed to identify patients with a history of HNSCC who underwent either primary or adjuvant radiation therapy (RT) and presented with hemorrhagic complications requiring embolization. Patient characteristics, history, presentation, and outcomes were reviewed. RESULTS: The systematic review included a total of 182 patients. Heterogeneity existed in outcomes reporting; 1-year overall survival approached 50%. From the retrospective chart review, 51 patients were included. Median survival time following hemorrhage was 2.2 months (range 1.2-11.4 months). Patients with malignancy at time of hemorrhage were identified as having worse survival. CONCLUSIONS: Acute hemorrhage in patients with a history of previously radiated HNSCC portends a high risk of mortality, with patients with active malignancy representing a worse prognostic group.

Risk of radionecrosis in HER2-positive breast cancer with brain metastasis receiving trastuzumab emtansine (T-DM1) and brain stereotactic radiosurgery.

OBJECTIVES: To investigate the potential relationship between trastuzumab emtansine (T-DM1) treatment and radionecrosis induced by brain stereotactic radiosurgery (SRS) in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. MATERIALS AND METHODS: Patients with HER2-positive breast cancer who were diagnosed with brain metastasis and received both SRS and HER2-targeted agents between 2012 and 2022 were retrospectively analyzed. Patients who received T-DM1 within 1 year (either before or after) of SRS were considered as 'T-DM1 exposure (+)'. T-DM1 exposure (-) group had other HER2-targeted agents or received T-DM1 more than 1 year before or after SRS. Symptomatic radionecrosis was defined as Common Terminology Criteria for Adverse Events grade 2 or greater. RESULTS: A total of 103 patients with 535 treatment sessions were included from seven tertiary medical centers in Korea and Italy. The median follow-up duration was 15.5 months (range 1.1-101.9). By per-patient analysis, T-DM1 exposure (+) group had an increased risk of overall radionecrosis after multivariate analysis (HR 2.71, p = 0.020). Additionally, T-DM1 exposure (+) group was associated with a higher risk of symptomatic radionecrosis compared to T-DM1 exposure (-) patients (HR 4.34, p = 0.030). In per-treatment analysis, T-DM1 exposure (+) was linked to higher incidences of overall (HR 3.13, p = 0.036) and symptomatic radionecrosis (HR 10.4, p = 0.013) after multivariate analysis. A higher prevalence of radionecrosis was observed with T-DM1 exposure (+) and a previous history of whole brain radiotherapy. CONCLUSION: An increased risk of radionecrosis was observed in patients receiving T-DM1 with brain SRS. Further research is needed to better understand the optimal sequence and interval for administering T-DM1 and SRS.

Determinants of cerebral radionecrosis in animal models: A systematic review.

BACKGROUND: Radionecrosis is a common complication in radiation oncology, while mechanisms and risk factors have yet to be fully explored. We therefore conducted a systematic review to understand the pathogenesis and identify factors that significantly affect the development. METHODS: We performed a systematic literature search based on the PRISMA guidelines using PubMed, Ovid, and Web of Science databases. The complete search strategy can be found as a preregistered protocol on PROSPERO (CRD42023361662). RESULTS: We included 83 studies, most involving healthy animals (n = 72, 86.75 %). High doses of hemispherical irradiation of 30 Gy in rats and 50 Gy in mice led repeatedly to radionecrosis among different studies and set-ups. Higher dose and larger irradiated volume were associated with earlier onset. Fractionated schedules showed limited effectiveness in the prevention of radionecrosis. Distinct anatomical brain structures respond to irradiation in various ways. White matter appears to be more vulnerable than gray matter. Younger age, more evolved animal species, and genetic background were also significant factors, whereas sex was irrelevant. Only 13.25 % of the studies were performed on primary brain tumor bearing animals, no studies on brain metastases are currently available. CONCLUSION: This systematic review identified various factors that significantly affect the induction of radionecrosis. The current state of research neglects the utilization of animal models of brain tumors, even though patients with brain malignancies constitute the largest group receiving brain irradiation. This latter aspect should be primarily addressed when developing an experimental radionecrosis model for translational implementation.

Prognostic Factors for Recurrent Glioma: A Population-Based Analysis.

Background: The overall survival (OS) for patients with recurrent glioma is meager. Also, the effect of radionecrosis and prognostic factors for recurrent glioma remains controversial. In this regard, developing effective predictive models and guiding clinical care is crucial for these patients. Methods: We screened patients with recurrent glioma after radiotherapy and those who received surgery between August 1, 2013, and December 31, 2020. Univariate and multivariate Cox regression analyses determined the independent prognostic factors affecting the prognosis of recurrent glioma. Moreover, nomograms were constructed to predict recurrent glioma risk and prognosis. Statistical methods were used to determine the prediction accuracy and discriminability of the nomogram prediction model based on the area under the curve (AUC), the C-index, the decision curve analysis (DCA), and the calibration curve. In order to distinguish high-risk and low-risk groups for OS, the X-Tile and Kaplan-Meier (K-M) survival curves were employed, and the nomogram prediction model was further validated by the X-Tile and K-M survival curves. Results: According to a Cox regression analysis, independent prognostic factors of recurrent glioma after radiotherapy with radionecrosis were World Health Organization (WHO) grade and gliosis percentage. We utilized a nomogram prediction model to analyze results visually. The C-index was 0.682 (95% CI: 0.616-0.748). According to receiver operating characteristic (ROC) analysis, calibration plots, and DCA, the nomogram prediction model was found to have a high-performance ability, and all patients were divided into low-risk and high-risk groups based on OS (P < .001). Conclusion: WHO grade and gliosis percentage are prognostic factors for recurrent glioma with radionecrosis, and a nomogram prediction model was established based on these two variables. Patients could be divided into high- and low-risk groups with different OS by this model, and it will provide individualized clinical decisions for future treatment.

[Clinical classification, staging and treatment strategy of radionecrosis of the nasopharynx and skull base].

Objective:To establish a staging system for guiding clinical treatment and prognostic risk assessment by retrospectively analyzing the cases with radionecrosis of the nasopharynx and skull base （RNSB） after radiotherapy for nasopharyngeal carcinoma. Methods:A total of 86 cases of RNSB from January 2019 to December 2022 visited Department of Otorhinolaryngology Head and Neck, the People's Hospital of Guangxi Zhuang Autonomous Region. Seventeen patients gave up the treatment, and 69 patients who underwent treatment were included for analysis. By analyzing the results of electronic nasopharyngolaryngoscopy combined with magnetic resonance （MR）, CT, and other imaging examinations, a staging system for RNSB was proposed. The relationship between the staging system and the surgical effectiveness and clinical prognosis was further analyzed. Results:According to the severity and extent of destruction of soft tissue, bone, and the adjacent neurovascular structures, the RNSB was categorized into closed type （n=5） and open type （n=64）, of which the open type was subdivided into five types: type Ⅰ（n=4）, type Ⅱ（n=6）, type Ⅲ（n=39, of which 21 cases were type Ⅲa and 18 cases were type Ⅲb）, type Ⅳ（n=12）, and type Ⅴ（n=8）. The clinical stage of RNSB were classified based on nasopharyngolaryngoscopy and imaging examinations, receiving the second course of radiotherapy or not, the involvement of the infection site, the extent of bone destruction, the degree of internal carotid artery involvement, and the degree of brain tissue necrosis: stageⅠ（1-2 scores）, 11 cases at stageⅡ（3-4 scores）, 24 cases at stage Ⅲ（5-6 scores）, and 30 cases at stage Ⅳ（ ≥ 7 scores or more）. Twenty-two patients chose conservative treatment （2 patients at stage Ⅰ, 3 patients at stage Ⅱ, 7 patients at stage Ⅲ, and 10 patients at stage Ⅳ）. Forty-seven patients chose nasal endoscopic surgical treatment （2 patients at stage Ⅰ, 8 patients at stage Ⅱ, 17 patients at stage Ⅲ, and 20 patients at stage Ⅳ）, of which 16 cases had received free mucosal flap and/or stented septum mucosal flap repair. Patients at stages Ⅰ, Ⅱ, and Ⅲ achieved satisfactory efficacy after surgical treatment. In addition, higher clinical stage was found to correlate with the worse prognosis and higher incidence of perioperative complications, which included failure of healing because of surgical site infection, cerebrospinal fluid nasal leakage, progressive osteonecrosis, nasopharyngeal hemorrhage, and death. Conclusion:The staging system proposed in our study can be used for early detection of RNSB during regular follow-up, and is also valuable for clinical treatment guidance and prognosis assessment.

MRI-based radiomics models predict cystic brain radionecrosis of nasopharyngeal carcinoma after intensity modulated radiotherapy.

Objective: To construct radiomics models based on MRI at different time points for the early prediction of cystic brain radionecrosis (CBRN) for nasopharyngeal carcinoma (NPC). Methods: A total of 202 injured temporal lobes from 155 NPC patients with radiotherapy-induced temporal lobe injury (RTLI) after intensity modulated radiotherapy (IMRT) were included in the study. All the injured lobes were randomly divided into the training (n = 143) and validation (n = 59) sets. Radiomics models were constructed by using features extracted from T2WI at two different time points: at the end of IMRT (post-IMRT) and the first-detected RTLI (first-RTLI). A delta-radiomics feature was defined as the percentage change in a radiomics feature from post-IMRT to first-RTLI. The radiomics nomogram was constructed by combining clinical risk factors and radiomics signatures using multivariate logistic regression analysis. Predictive performance was evaluated using area under the curve (AUC) from receiver operating characteristic analysis and decision curve analysis (DCA). Results: The post-IMRT, first-RTLI, and delta-radiomics models yielded AUC values of 0.84 (95% CI: 0.76-0.92), 0.86 (95% CI: 0.78-0.94), and 0.77 (95% CI: 0.67-0.87), respectively. The nomogram exhibited the highest AUC of 0.91 (95% CI: 0.85-0.97) and sensitivity of 0.82 compared to any single radiomics model. From the DCA, the nomogram model provided more clinical benefit than the radiomics models or clinical model. Conclusion: The radiomics nomogram model combining clinical factors and radiomics signatures based on MRI at different time points after radiotherapy showed excellent prediction potential for CBRN in patients with NPC.

Unmasking the Mimic: Radionecrotic Lesion Masquerading as Brain Neoplasia on Magnetic Resonance Imaging.

Corpus callosotomy is a therapeutic approach for drug-resistant epilepsy, with positive outcomes observed in managing atonic seizures. Despite a decline in its usage, radiosurgical callosotomy remains a viable option for drug-resistant epilepsy due to its low risks of post-radiation neoplasia, albeit not with exceptions. Brain radionecrosis is characterized by tissue death and vascular endothelial damage following the procedure. Despite the low risk of intracranial secondary malignancy associated with radiation in some cases, post-radiation lesions might present with distinct characteristics needing a thorough diagnostic approach. Herein, we present a unique case of a patient with focal epilepsy who developed a radionecrotic lesion following radiosurgical callosotomy, affecting the anterior cingulate cortex, and mimicking a central nervous system (CNS) tumor. Molecular imaging techniques, including 18-fluorodeoxyglucose positron emission tomography/computed tomography (18-FDG PET/CT) and 11C-acetate PET/CT scans, were employed to differentiate the lesion from a tumor. This case underscores the importance of considering radionecrosis as a differential diagnosis in patients who undergo radiosurgical callosotomy presenting with ring-like enhancement lesions on magnetic resonance imaging (MRI).

Investigation of the risk factors in the development of radionecrosis in patients with brain metastases undergoing stereotactic radiotherapy.

OBJECTIVE: To investigate the incidence, timing, and the factors predictors radionecrosis (RN) development in brain metastases (BMs) undergoing stereotactic radiotherapy (SRT). METHODS: The study evaluated 245 BMs who exclusively received SRT between 2010 and 2020. RN was detected pathologically or radiologically. RESULTS: The median of follow-up was 22.6 months. RN was detected in 18.4% of the metastatic lesions, and 3.3% symptomatic, 15.1% asymptomatic. The median time of RN was 22.8 months (2.5-39.5), and the rates at 6, 12, and 24 months were 16.8%, 41.4%, and 66%, respectively. Univariate analysis revealed that Graded Prognostic Assessment (P = .005), Score Index of Radiosurgery (P = .015), Recursive Partitioning Analysis (P = .011), the presence of primary cancer (P = .004), and localization (P = .048) significantly increased the incidence of RN. No significant relationship between RN and brain-gross tumour volume doses, planning target volume, fractionation, dose (P > .05). Multivariate analysis identified SIR > 6 (OR: 1.30, P = .021), primary of breast tumour (OR: 2.33, P = .031) and supratentorial localization (OR: 3.64, P = .025) as risk factors. CONCLUSIONS: SRT is used effectively in BMs. The incidence of RN following SRT is undeniably frequent. It was observed that the incidence rate increased as the follow-up period increased. We showed that brain-GTV doses are not predictive of RN development, unlike other publications. In study, a high SIR score and supratentorial localization were identified as factors that increased the risk of RN. ADVANCES IN KNOWLEDGE: RN is still a common complication after SRT. Symptomatic RN is a significant cause of morbidity. The causes of RN are still not clearly identified. In many publications, brain dose and volumes have been found to be effective in RN. But, with this study, we found that brain dose volumes and fractionation did not increase the incidence of RN when brain doses were taken into account. The most important factor in the development of RN was found to be related to long survival after SRT.

Contrast Clearance Analysis (CCA) to Assess Viable Tumour following Stereotactic Radiosurgery (SRS) to Brain Metastasis in Non-Small Cell Lung Cancer (NSCLC).

BACKGROUND AND OBJECTIVE: Brain metastases are common in lung cancer and increasingly treated using targeted radiotherapy techniques such as stereotactic radiosurgery (SRS). Using MRI, post-SRS changes may be difficult to distinguish from progressive brain metastasis. Contrast clearance analysis (CCA) uses T1-weighted MRI images to assess the clearance of gadolinium and can be thus used to assess vascularity and active tumours. DESIGN AND METHODS: We retrospectively assessed CCAs in 62 patients with non-small cell lung cancer (NSCLC) undergoing 104 CCA scans in a single centre. RESULTS: The initial CCA suggested the aetiology of equivocal changes on standard MRI in 80.6% of patients. In all patients whose initial CCA showed post-SRS changes and who underwent serial CCAs, the initial diagnosis was upheld with the serial imaging. In only two cases of a presumed progressive tumour on the initial CCA, subsequent treatment for radionecrosis was instigated; a retrospective review and re-evaluation of the CCAs show that progression was reported where a thin rim of rapid contrast clearance was seen, and this finding has been subsequently recognised as a feature of post-treatment change on CCAs. The lack of concordance with CCA findings in those who underwent surgical resection was also found to be due to the over-reporting of the thin blue rim as disease in the early cases of CCA use and, in three cases, potentially related to timelines longer than 7 days prior to surgery, both factors being unknown during the early implementation phase of CCA at our centre but subsequently learned. CONCLUSIONS: Our single-centre experience shows CCA to be feasible and useful in patients with NSCLC in cases of diagnostic uncertainty in MRI. It has helped guide treatment in the majority of patients, with subsequent outcomes following the implementation of the treatment based on the results, suggesting correct classification. Recommendations from our experience of the implementation include the careful consideration of the thin rim of the rapid contrast clearance and the timing of the CCA prior to surgery for suspected brain metastasis progression.

Análisis visual y semicuantitativo del 6-[18F]FDOPA PET/TC en pacientes con tumores cerebrales ante la sospecha de recurrencia tumoral versus radionecrosis / VAnálisis visual y semicuantitativo del 6-[18F]FDOPA PET/TC en pacientes con tumores cerebrales ante la sospecha de recurrencia tumoral versus radionecrosis

Introducción La tomografía por emisión de positrones (PET) con aminoácidos es una herramienta recomendada por las principales sociedades de neuroimagen, en el diagnóstico diferencial entre radionecrosis (RNC) y recurrencia tumoral (RT) en los tumores cerebrales, sin embargo, su uso en nuestro pais aún es limitado. El objetivo de este trabajo es presentar nuestra experiencia con 6-[18F]FDOPA PET/TC (FDOPA) en tumores cerebrales (primarios y M1), comparando estos resultados con otros publicados. Material y métodos Estudio retrospectivo de 62 pacientes con sospecha de RT: 42 metástasis cerebrales (M1) y 20 primarios, a los que se les realizó una FDOPA. Las imágenes fueron analizadas visual y semicuantitativamente, obteniendo el SUVmax y los ratios SUVmaxlesión/SUVmaxestriado (L/E) y SUVmaxlesión/SUVmaxcortex (L/C). Se analizó la validez diagnóstica de la PET y se calcularon los puntos de corte con mayor rendimiento. Los resultados de la PET se compararon con la evolución clínico-radiológica y/o con la histopatología. Resultados Se identificó RT en el 49% de las M1 y en el 76% de los primarios cerebrales. La interpretación de la FDOPA con mejores resultados fue la conjunta; visual y semicuantitativa, con una sensibilidad y especificidad en los primarios del 94 y 80% y en las M1 del 96 y 72%, respectivamente. Los puntos de corte con mejor rendimiento diagnóstico fueron L/C 1,44 en M1 y L/C 1,55 en primarios. Existen resultados discrepantes con otros publicados. Conclusión La FDOPA PET/TC es una herramienta útil en el diagnóstico diferencial entre RT y RNC en tumores cerebrales. Es necesario una estandarización que contribuya a homogeneizar los resultados de la FDOPA a nivel intercentro (AU)

Introduction Amino acid PET is a tool recommended by the main neuroimaging societies in the differential diagnosis between radionecrosis (RNC) and tumour recurrence (TR) in brain tumours, but its use in our country is still limited. The aim of this work is to present our experience with 6-[18F]FDOPA PET/CT (FDOPA) in brain tumours (primary and M1), comparing these results with other published results. Material and methods Retrospective study of 62 patients with suspected tumour recurrence (TR): 42 brain metastases (M1) and 20 primary, who underwent FDOPA. Images were analysed visually and semi-quantitatively, obtaining SUVmax and SUVmaxlesion/SUVmaxstriatum (L/S) and SUVmaxlesion/SUVmaxcortex (L/C) ratios. The diagnostic validity of PET was analysed and the best performing cut-off points were calculated. PET results were compared with clinical-radiological follow-up and/or histopathology. Results TR was identified in 49% of M1 and 76% of brain primaries. The best performing FDOPA interpretation was visual and semi-quantitative, with a sensitivity and specificity in primaries of 94% and 80% and in M1s of 96% and 72% respectively. The cut-off points with the best diagnostic performance were L/C1.44 in M1 and L/C1.55 in primaries. There are discrepant results with other published results. Conclusion FDOPA PET/CT is a useful tool in the differential diagnosis between recurrence and RNC in brain tumours. It is needed a standardization to contribute to homogenise FDOPA results a inter-centre level (AU)

Radionecrosis cerebral en un adulto

Se presenta el caso clínico de un paciente de 37 años de edad con el antecedente de haber recibido radioterapia por una lesión tumoral en la región frontal derecha, el cual acudió a consulta en el Instituto de Neurología y Neurocirugía de Cuba por presentar cefalea intensa y hemiparesia izquierda. Luego de realizados los exámenes necesarios, se estableció el diagnóstico clínico-imagenológico de lesión por radionecrosis en el hemisferio contralateral, que fue corroborado en el estudio anatomopatológico una vez que se extirpó el tumor; seguidamente, se indicó inmunoterapia. La evolución del paciente fue satisfactoria, pues se logró el control de la enfermedad y la resolución de los síntomas.

The case report of a 37-year-old patient with history of having received radiotherapy due to a tumor lesion in the right frontal region is presented, who attended to the Institute of Neurology and Neurosurgery in Cuba because of intense headache and left hemiparesis. After carrying out the necessary examinations, the clinical-imaging diagnosis of a radionecrosis lesion in the contralateral hemisphere was established, which was corroborated in the pathological examination once the tumor was removed; then, immunotherapy was indicated. The patient had a favorable clinical course because the control of the disease was achieved as well as the resolution of symptoms.

Umbrella review and network meta-analysis of diagnostic imaging test accuracy studies in Differentiating between brain tumor progression versus pseudoprogression and radionecrosis.

PURPOSE: In this study we gathered and analyzed the available evidence regarding 17 different imaging modalities and performed network meta-analysis to find the most effective modality for the differentiation between brain tumor recurrence and post-treatment radiation effects. METHODS: We conducted a comprehensive systematic search on PubMed and Embase. The quality of eligible studies was assessed using the Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) instrument. For each meta-analysis, we recalculated the effect size, sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio from the individual study data provided in the original meta-analysis using a random-effects model. Imaging technique comparisons were then assessed using NMA. Ranking was assessed using the multidimensional scaling approach and by visually assessing surface under the cumulative ranking curves. RESULTS: We identified 32 eligible studies. High confidence in the results was found in only one of them, with a substantial heterogeneity and small study effect in 21% and 9% of included meta-analysis respectively. Comparisons between MRS Cho/NAA, Cho/Cr, DWI, and DSC were most studied. Our analysis showed MRS (Cho/NAA) and 18F-DOPA PET displayed the highest sensitivity and negative likelihood ratios. 18-FET PET was ranked highest among the 17 studied techniques with statistical significance. APT MRI was the only non-nuclear imaging modality to rank higher than DSC, with statistical insignificance, however. CONCLUSION: The evidence regarding which imaging modality is best for the differentiation between radiation necrosis and post-treatment radiation effects is still inconclusive. Using NMA, our analysis ranked FET PET to be the best for such a task based on the available evidence. APT MRI showed promising results as a non-nuclear alternative.

Intrinsic stenosing and occlusive pathologies of the vertebral artery: A narrative review.

Intrinsic pathologies of the vertebral arteries, such as atherosclerosis, dissection, fibromuscular dysplasia, radionecrosis and vasculitis, are important causes of vertebrobasilar insufficiency and cerebrovascular events. This review focuses on non-aneurysmal intrinsic stenosing and occlusive pathologies, covering their epidemiology, diagnosis, and treatment options. It also provides a detailed summary of key clinical presentations and syndromes, including an in-depth examination of lateral medullary syndrome, historically known as Wallenberg's syndrome, which is arguably the most emblematic condition resulting from vertebral artery involvement and is depicted in an illustrative cartoon.

Radiation therapy, tissue radiosensitization, and potential synergism in the era of novel antibody-drug conjugates.

Antibody-drug conjugates (ADCs) represent a therapeutic class of agents designed to selectively deliver cytotoxic payloads to cancer cells. With the increasingly positioning of ADCs in the clinical practice, combinations with other treatment modalities, including radiation therapy (RT), will open new opportunities but also challenges. This review evaluates ADC-RT interactions, examining therapeutic synergies and potential caveats. ADC payloads can be radiosensitizing, enhancing cytotoxicity when used in combination with RT. Antigens targeted by ADCs can have various tissue expressions, resulting in possible off-target toxicities by tissue radiosensitization. Notably, the HER-2-directed ADC trastuzumab emtansine has appeared to increase the risk of radionecrosis when used concomitantly with brain RT, as glial cells can express HER2, too. Other possible organ-specific effects are discussed, such as pulmonary and cardiac toxicities. The lack of robust clinical data on the ADC-RT combination raises concerns regarding specific side effects and the ultimate trade-off of toxicity and safety of some combined approaches. Clinical studies are needed to assess ADC-RT combination safety and efficacy.

Visual and semi-quantitative analysis of 6-[18F]FDOPA PET/CT in patients with brain tumors and suspected tumor recurrence versus radionecrosis.

INTRODUCTION: Amino acid PET is a tool recommended by the main neuroimaging societies in the differential diagnosis between radionecrosis (RNC) and umour recurrence (TR) in brain tumours, but its use in our country is still limited. The aim of this work is to present our experience with 6-[18F]FDOPA PET/CT (FDOPA) in brain tumours (primary and M1), comparing these results with other published results. MATERIAL AND METHODS: Retrospective study of 62 patients with suspected tumour recurrence (TR): 42 brain metastases (M1) and 20 primary, who underwent FDOPA. Images were analysed visually and semi-quantitatively, obtaining SUVmax and SUVmaxlesion/SUVmaxstriatum (L/S) and SUVmaxlesion/SUVmaxcortex (L/C) ratios. The diagnostic validity of PET was analysed and the best performing cut-off points were calculated. PET results were compared with clinical-radiological follow-up and/or histopathology. RESULTS: TR was identified in 49% of M1 and 76% of brain primaries. The best performing FDOPA interpretation was visual and semi-quantitative, with a sensitivity and specificity in primaries of 94% and 80% and in M1s of 96% and 72% respectively. The cut-off points with the best diagnostic performance were L/C1.44 in M1 and L/C1.55 in primaries. There are discrepant results with other published results. CONCLUSION: FDOPA PET/CT is a useful tool in the differential diagnosis between recurrence and RNC in brain tumours. It is needed a standardization to contribute to homogenise FDOPA results a inter-centre level.

Histopathologically confirmed radiation-induced damage of the brain - an in-depth analysis of radiation parameters and spatio-temporal occurrence.

BACKGROUND: Radiation-induced damage (RID) after radiotherapy (RT) of primary brain tumors and metastases can be challenging to clinico-radiographically distinguish from tumor progression. RID includes pseudoprogression and radiation necrosis; the latter being irreversible and often associated with severe symptoms. While histopathology constitutes the diagnostic gold standard, biopsy-controlled clinical studies investigating RID remain limited. Whether certain brain areas are potentially more vulnerable to RID remains an area of active investigation. Here, we analyze histopathologically confirmed cases of RID in relation to the temporal and spatial dose distribution. METHODS: Histopathologically confirmed cases of RID after photon-based RT for primary or secondary central nervous system malignancies were included. Demographic, clinical, and dosimetric data were collected from patient records and treatment planning systems. We calculated the equivalent dose in 2 Gy fractions (EQD22) and the biologically effective dose (BED2) for normal brain tissue (α/ß ratio of 2 Gy) and analyzed the spatial and temporal distribution using frequency maps. RESULTS: Thirty-three patients were identified. High-grade glioma patients (n = 18) mostly received one normofractionated RT series (median cumulative EQD22 60 Gy) to a large planning target volume (PTV) (median 203.9 ccm) before diagnosis of RID. Despite the low EQD22 and BED2, three patients with an accelerated hyperfractionated RT developed RID. In contrast, brain metastases patients (n = 15; 16 RID lesions) were often treated with two or more RT courses and with radiosurgery or fractionated stereotactic RT, resulting in a higher cumulative EQD22 (median 162.4 Gy), to a small PTV (median 6.7 ccm). All (n = 34) RID lesions occurred within the PTV of at least one of the preceding RT courses. RID in the high-grade glioma group showed a frontotemporal distribution pattern, whereas, in metastatic patients, RID was observed throughout the brain with highest density in the parietal lobe. The cumulative EQD22 was significantly lower in RID lesions that involved the subventricular zone (SVZ) than in lesions without SVZ involvement (median 60 Gy vs. 141 Gy, p = 0.01). CONCLUSIONS: Accelerated hyperfractionated RT can lead to RID despite computationally low EQD22 and BED2 in high-grade glioma patients. The anatomical location of RID corresponded to the general tumor distribution of gliomas and metastases. The SVZ might be a particularly vulnerable area.

Five-Fraction Radiosurgery Using a Biologically Equivalent Dose of a Single Fraction of 24 Gy for a 3-cm Parasagittal Para-Central Sulcus Brain Metastasis From Adenocarcinoma of the Cecum.

An isolated single brain metastasis (BM) is an extremely rare manifestation of failure in patients with cecal adenocarcinoma (CAC). Total en bloc resection (while preserving function) of a 3-cm BM involving both the primary motor and sensory cortexes presents a conundrum: achieving long-term local control and safety of such a BM is also challenging for stereotactic radiosurgery (SRS). We describe the case of a 3.1-cm BM from CAC in the left parasagittal para-central sulcus region, which was treated using five-fraction SRS with a biologically effective dose (BED) of 81.6 Gy. In the SRS, the gross tumor volume (GTV, 7.14 cm3) was defined based on computed tomography (CT)/T1/T2 matching (enhancing lesion 11.66 cm3), and 98.7% of the GTV (CT/T2 mass) was covered with 43.6 Gy (58% isodose) using volumetric-modulated arcs. The maximum tumor response was partial (19.7% of the prior GTV) and sustained for 15.2 months, leaving minor neurological symptoms. However, the patient developed neurological worsening at six months, attributed to adverse radiation effects with a CT/T1/T2 mismatch, for which medical management, including the addition of bevacizumab (BEV), was effective for one year. Multi-fraction SRS with a high marginal and internal BED and sequential systemic therapy, including BEV, can be a minimally invasive, efficacious, and durable treatment option for a large CAC-BM involving the central sulcus. Early co-administration of BEV following SRS, dose escalation to the GTV boundary, and more than five fractions of SRS may be considered to improve the efficacy and safety further.

Corrigendum: Impressive reduction of brain metastasis radionecrosis after cabozantinib therapy in metastatic renal carcinoma: a case report and review of the literature.

[This corrects the article DOI: 10.3389/fonc.2023.1136300.].

Pelvic exenteration for chronic fistulating pelvic sepsis after multimodal treatment of pelvic malignancy.

BACKGROUND: Chronic fistulating pelvic sepsis is an uncommon complication of multimodal treatment of visceral pelvic tumours. Radical multi-visceral resection is reserved for patients with persistent, debilitating symptoms despite less invasive treatments and for which there is minimal published data. This study aimed to report the rates of morbidity and long-term sepsis control after pelvic exenteration for chronic fistulating pelvic sepsis. METHODS: This retrospective cohort study was conducted at a high-volume pelvic exenteration referral centre. Patients who underwent pelvic exenteration for chronic fistulating pelvic sepsis between September 1994 and January 2023 after previous treatment for pelvic malignancy were included. Data relating to postoperative morbidity, mortality and the rate of recurrent pelvic sepsis or fistulae were retrospectively collected. RESULTS: 19 patients who underwent radical resection for chronic fistulating pelvic sepsis after previous pelvic cancer treatment were included. 11 patients were male (58 %) and median age was 62 years (range 42-79). Previously treated rectal (8 patients, 42 %), prostate (5, 26 %) and cervical cancer (5, 26 %) were most common. 18 patients (95 %) had previously received high-dose pelvic radiotherapy, and 14 (74 %) had required surgical resection. Total pelvic exenteration was performed in 47 % of patients, total cystectomy in 68 % and major pubic bone resection in 37 %. There was no intraoperative or postoperative mortality. Major complication rate was 32 %. 12-month readmission rate was 42 %. At last follow up, 74 % had no signs or symptoms of persisting pelvic sepsis. CONCLUSIONS: Pelvic exenteration for refractory pelvic sepsis following treatment of malignancy is safe and effective in selected patients.