Intratumoral and Peritumoral Edema Radiomics Based on Fat-Suppressed T2- Weighted Imaging for Preoperative Prediction of Triple-Negative Breast Cancer

AIM

Our aim was to explore the feasibility of using radiomics data derived from intratumoral and peritumoral edema on fat-suppressed T2-weighted imaging (T2 FS) to distinguish triple-negative breast cancer (TNBC) from non-triple-negative breast cancer (non-TNBC).

METHODS

This retrospective study enrolled 174 breast cancer patients. According to the MRI examination time, patients before 2021 were divided into training (n = 119) or internal test (n = 30) cohorts at a ratio of 8:2. Patients from 2022 were included in the external test cohort (n = 25). Four regions of interest for each lesion were defined: intratumoral regions, peritumoral edema regions, regions with a combination of intratumoral and peritumoral edema, and regions with a combination of intratumoral and 5-mm peritumoral. Four radiomic signatures were built using the least absolute shrinkage and selection operator (LASSO) method after selecting features. Furthermore, a radio mic-radiological model was constructed using a combination of intratumoral and peritumoral edema regions along with clinical-radiologic features. Area under the receiver operating characteristic curve (AUC) calculations, decision curve analysis, and calibration curve analysis were performed to assess the performance of each model.

RESULTS

The radiomic-radiological model showed the highest AUC values of 0.906 (0.788-1.000) and 82.5 (0.622-0.947) in both the internal and external test sets, respectively. The radiology-radiomic model exhibited excellent predictive performance, as evidenced by the calibration curves and decision curve analysis.

CONCLUSION

The ensemble model based on T2 FS-based radiomic features of intratumoral and peritumoral edema, along with radiological factors, performed better in distinguishing TNBC from non-TNBC than a single model. We explored the possibility of developing explainable models to support the clinical decision-making process.

Clinical Value of a Nomogram Model Based on Apparent Diffusion Coefficient Values Within 1 cm of the Tumor Cavity to Predict Postoperative Progression of Glioma

OBJECTIVE

To explore the clinical value of constructing a nomogram model based on apparent diffusion coefficient values within 1 cm of the residual tumor cavity to predict the postoperative progression of gliomas.

METHODS

Clinical data of patients with glioma who underwent surgery were retrospectively retrieved from the First Hospital of Qinhuangdao. The mean apparent diffusion coefficient (mADC) was measured using a picture archiving and communication system. The Kaplan-Meier survival curve was constructed with the optimal mADC threshold determined by the X-tile. A nomogram was developed based on the independent risk factors determined using the Cox proportional hazards model (Cox regression model) to predict the progression of postoperative glioma. A receiver operating characteristic curve was drawn to evaluate the prediction accuracy of the model, and decision curve analysis was performed to assess the clinical value of the nomogram.

RESULTS

There was good agreement between the mADC values of the 2 repeated measurements before and after, with a consistency correlation coefficient of 0.83. Multivariate Cox regression analysis showed that peritumoral mADC values, degree of peritumoral enhancement, age, pathological grading, and degree of tumor resection were independent risk factors for predicting postoperative progression of glioma (all P < 0.05). The receiver operating characteristic curves of the nomogram predicting 1, 2, and 3 years postoperative progression were 0.86, 0.82, and 0.91, respectively. The calibration curve showed good consistency between the observed and predicted values in the model. The curve showed that the nomogram model has a good clinical application value.

CONCLUSIONS

The peritumoral mADC values, degree of peritumoral enhancement, age, pathological grade, and degree of tumor resection were independent factors affecting the postoperative progression of glioma. The nomogram model established for the first time based on mADC values within 1 cm of the tumor can predict the postoperative condition of patients with glioma intuitively and comprehensively. It can provide a relatively accurate prediction tool for neurosurgeons to individualize the evaluation of survival and prognosis, and formulate treatment plans for patients.

Surgical outcomes in large vestibular schwannomas: should cerebellopontine edema be considered in the grading systems?

PURPOSE

Large (> 3 cm) vestibular schwannomas pose complexity in surgical management because of narrow working corridors and proximity to the cranial nerves, brainstem, and inner ear structures. With current vestibular schwannoma classifications limited in information regarding cerebellopontine edema, our retrospective series examined this radiographic feature relative to clinical outcomes and its possible role in preoperative scoring.

METHODS

Of 230 patients who underwent surgical resection of vestibular schwannoma (2014-2020), we identified 107 patients with Koos grades 3 or 4 tumors for radiographic assessment of edema in the middle cerebellar peduncle (MCP), brainstem, or both. Radiographic images were graded and patients grouped into Koos grades 3 or 4 or our proposed grade 5 with edema. Tumor volumes, radiographic features, clinical presentations, and clinical outcomes were evaluated.

RESULTS

The 107 patients included 22 patients with grade 3 tumors, 39 with grade 4, and 46 with grade 5. No statistical differences were noted among groups for demographic data or complication rates. Unlike grades 3 and 4 patients, grade 5 patients presented with worse hearing (p < 0.001), larger tumors (p < 0.001), lower rates of gross total resection (GTR), longer hospital stays, and higher rates of balance dysfunction.

CONCLUSION

With edema detected in 43% of this cohort, special considerations are warranted for grade 5 vestibular schwannomas given the preoperative findings of worse hearing, lower GTR rates, longer hospital stays, and 96% who pursued postoperative balance therapy. We propose that grade 5 with edema offers a more nuanced interpretation of a radiographic feature that holds relevance to treatment selection and patient outcomes.

Peritumoral edema in meningiomas: pathophysiology, predictors, and principles for treatment

Meningiomas is a tumor of the meninges and is among the most common intracranial neoplasms in adults, accounting for over a third of all primary brain tumors in the United States. Meningiomas can be associated with peritumoral brain edema (PTBE) which if not managed appropriately can lead to poor clinical outcomes. In this review, we summarize the relevant pathophysiology, predictors, and principles for treatment of PTBE. The results of various case-reports and case-series have found that meningioma-associated PTBE have patterns in age, tumor size, and hormone receptor positivity. Our study describes how increased age, increased tumor size, tumor location in the middle fossa, and positive expression of hormone receptors, VEGF, and MMP-9 can all be predictors for worse clinical outcomes. We also characterize treatment options for PTBE such as glucocorticoids and VEGF inhibitors along with the ongoing clinical trials attempting to alleviate PTBE in meningioma cases. The trends summarized in this review can be used to better predict the behavior of meningioma-associated PTBE and establish prognosis models to identify at risk patients.

An initial study on the predictive value using multiple MRI characteristics for Ki-67 labeling index in glioma

BACKGROUND AND PURPOSE

Ki-67 labeling index (LI) is an important indicator of tumor cell proliferation in glioma, which can only be obtained by postoperative biopsy at present. This study aimed to explore the correlation between Ki-67 LI and apparent diffusion coefficient (ADC) parameters and to predict the level of Ki-67 LI noninvasively before surgery by multiple MRI characteristics.

METHODS

Preoperative MRI data of 166 patients with pathologically confirmed glioma in our hospital from 2016 to 2020 were retrospectively analyzed. The cut-off point of Ki-67 LI for glioma grading was defined. The differences in MRI characteristics were compared between the low and high Ki-67 LI groups. The receiver operating characteristic (ROC) curve was used to estimate the accuracy of each ADC parameter in predicting the Ki-67 level, and finally a multivariate logistic regression model was constructed based on the results of ROC analysis.

RESULTS

ADC_min, ADC_mean, rADC_min, rADC_mean and Ki-67 LI showed a negative correlation (r = - 0.478, r = - 0.369, r = - 0.488, r = - 0.388, all P < 0.001). The Ki-67 LI of low-grade gliomas (LGGs) was different from that of high-grade gliomas (HGGs), and the cut-off point of Ki-67 LI for distinguishing LGGs from HGGs was 9.5%, with an area under the ROC curve (AUROC) of 0.962 (95%CI 0.933-0.990). The ADC parameters in the high Ki-67 group were significantly lower than those in the low Ki-67 group (all P < 0.05). The peritumoral edema (PTE) of gliomas in the high Ki-67 LI group was higher than that in the low Ki-67 LI group (P < 0.05). The AUROC of Ki-67 LI level assessed by the multivariate logistic regression model was 0.800 (95%CI 0.721-0.879).

CONCLUSIONS

There was a negative correlation between ADC parameters and Ki-67 LI, and the multivariate logistic regression model combined with peritumoral edema and ADC parameters could improve the prediction ability of Ki-67 LI.

Observation of the delineation of the target volume of radiotherapy in adult-type diffuse gliomas after temozolomide-based chemoradiotherapy: analysis of recurrence patterns and predictive factors

BACKGROUND

Radiation therapy is the cornerstone of treatment for adult-type diffuse gliomas, but recurrences are inevitable. Our study assessed the prognosis and recurrence pattern of different radiotherapy volumes after temozolomide-based chemoradiation in our institution.

METHODS

The treatment plans were classified into two groups, the plan 1 intentionally involved the entire edema area while plan 2 did not. Retrospectively investigate the differences in outcomes of 118 adult-type diffuse gliomas patients between these two treatment plans. Then, patients who underwent relapse were selected to analyze their recurrence patterns. Continuous dynamic magnetic resonance images (MRI) were collected to categorized the recurrence patterns into central, in-field, marginal, distant, and cerebrospinal fluid dissemination (CSF-d) recurrence. Finally, the clinical and molecular characteristics which influenced progression were analyzed.

RESULTS

Plan 1 (n = 63) showed a median progression-free survival (PFS) and overall survival (OS) of 9.5 and 26.4 months while plan 2 (n = 55) showed a median PFS and OS of 9.4 and 36.5 months (p = 0.418; p = 0.388). Treatment target volume had no effect on the outcome in patients with adult-type diffuse gliomas. And there was no difference in radiation toxicity (p = 0.388). Among the 90 relapsed patients, a total of 58 (64.4%) patients had central recurrence, 10 (11.1%) patients had in-field recurrence, 3 (3.3%) patients had marginal recurrence, 11 (12.2.%) patients had distant recurrence, and 8 (8.9%) patients had CSF-d recurrence. By treatment plans, the recurrence patterns were similar and there was no significant difference in survival. Reclassifying the progression pattern into local and non-local groups, we observed that oligodendroglioma (n = 10) all relapsed in local and no difference in PFS and OS between the two groups (p > 0.05). Multivariable analysis showed that subventricular zone (SVZ) involvement was the independent risk factor for non-local recurrence in patients with GBM (p < 0.05).

CONCLUSION

In our study, deliberately including or not the entire edema had no impact on prognosis and recurrence. Patients with varied recurrence patterns had diverse clinical and genetic features.

Radiological characteristics of spinal hemangioblastomas in von Hippel Lindau disease as guidance in clinical interventions

Hemangioblastomas in the central nervous system (CNS) are the most common manifestation of Von Hippel-Lindau (VHL) disease. Because the growth rate of hemangioblastomas is unpredictable, regular follow-up is mandatory, focusing on clinical symptoms and imaging of the CNS. However, clinical symptoms may be subtle and non-specific, and data about the relationship between the radiological findings and clinical symptoms are sparse.

AIM OF THE STUDY

This study aims to evaluate if and how findings of magnetic resonance imaging (MRI) regarding spinal hemangioblastomas are associated with symptoms of VHL disease, with special attention to peritumoral edema and spinal cysts.

METHODS

Serial spinal MRI scans of 43 genetically or clinically established VHL patients with at least two years of follow-up were re-evaluated to examine the volume, growth rate, and location of spinal hemangioblastomas and the presence, size, and growth rate of peritumoral edema and cysts. Findings were compared with clinical symptoms using Fisher's exact test.

RESULTS

We observed a total of 77 spinal hemangioblastomas in 28 patients. Eight of the 28 patients showed peritumoral edema and spinal cysts, and one patient showed peritumoral edema without cyst formation; six of these nine patients showed clinical symptoms. Both peritumoral edema and spinal cysts were associated with clinical symptoms (P=0.023 and P=0.011, respectively).

CONCLUSION

The presence of peritumoral edema and/or spinal cysts shown on MRI in VHL-patients with spinal hemangioblastomas is associated with symptoms in more than half of the patients and may alert the clinician to intensify clinical and radiological surveillance.

Application of diffusion kurtosis imaging to the study of edema in solid and peritumoral areas of glioma

OBJECTIVE

When gliomas grow in an infiltrative form, high-grade malignant glioma tissue extends beyond the contrast-enhancing tumor boundary, and this diffuse non-enhancing tumor infiltration is not visible on conventional MRI. The purpose of this study was to evaluate the of diffusion kurtosis imaging (DKI)-derived parameters in a group of patients with pre-operative gliomas, evaluating changes in the solid tumor and peritumoral edema area, and investigating their use for evaluating the recurrence and prognosis of gliomas.

METHODS

In this retrospective study, 51 patients with gliomas who underwent biopsy or surgery underwent DKI scans before surgery. DKI scans were performed to generate DKI parameter maps of the solid tumor and peritumoral edema areas. In the solid tumor area, the kurtosis parameters showed the highest area under the curve (AUC), sensitivity, and specificity for distinguishing high- and low-grade gliomas (all P < 0.01).

RESULTS

In the peritumoral edema area, significant differences were found between groups with grade III and IV gliomas (P < 0.05). DKI parameters were found to correlate with clinical Ki-67 scores within the solid tumor area (MK: R2 = 0.288, P < 0.001; Kr: R2 = 0.270, P < 0.001; Ka: R2 = 0.274, P < 0.001; MD: R2 = 0.223, P < 0.001; FA: R2 = 0.098, P < 0.01). No significant correlations were found between Ki-67 and kurtosis parameters of peritumoral edema.

CONCLUSIONS

In this study, DKI showed potential utility for studying solid tumor and peritumoral edema of high grade gliomas.

Peritumoral edema status of glioblastoma identifies patients reaching long-term disease control with specific progression patterns after tumor resection and high-dose proton boost

Background

Glioblastoma peritumoral edema (PE) extent is associated with survival and progression pattern after tumor resection and radiotherapy (RT). To increase tumor control, proton beam was adopted to give high-dose boost (> 90 Gy). However, the correlation between PE extent and prognosis of glioblastoma after postoperative high-dose proton boost (HDPB) therapy stays unknown. We intend to utilize the PE status to classify the survival and progression patterns.

Methods

Patients receiving HDPB (96.6 GyE) were retrospectively evaluated. Limited peritumoral edema (LPE) was defined as PE extent < 3 cm with a ratio of PE extent to tumor maximum diameter of < 0.75. Extended progressive disease (EPD) was defined as progression of tumors extending > 1 cm from the tumor bed edge.

Results

After long-term follow-up (median 88.7, range 63.6–113.8 months) for surviving patients with (n = 13) and without (n = 32) LPE, the median overall survival (OS) and progression-free survival (PFS) were 77.2 vs. 16.7 months (p = 0.004) and 13.6 vs. 8.6 months (p = 0.02), respectively. In multivariate analyses combined with factors of performance, age, tumor maximum diameter, and tumor resection extent, LPE remained a significant factor for favorable OS and PFS. The rates of 5-year complete response, EPD, and distant metastasis with and without LPE were 38.5% vs. 3.2% (p = 0.005), 7.7% vs. 40.6% (p = 0.04), and 0% vs. 34.4% (p = 0.02), respectively.

Conclusions

The LPE status effectively identified patients with relative long-term control and specific progression patterns after postoperative HDPB for glioblastoma.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03765-6.

Advanced MRI assessment of non-enhancing peritumoral signal abnormality in brain lesions

Evaluation of Central Nervous System (CNS) focal lesions has been classically made focusing on the assessment solid or enhancing component. However, the assessment of solitary peripherally enhancing lesions where the differential diagnosis includes High-Grade Gliomas (HGG) and metastasis, is usually challenging. Several studies have tried to address the characteristics of peritumoral non-enhancing areas, for better characterization of these lesions. Peritumoral hyperintense T2/FLAIR signal abnormality predominantly contains infiltrating tumor cells in HGG whereas CNS metastasis induce pure vasogenic edema. In addition, the accurate determination of the real extension of HGG is critical for treatment selection and outcome. Conventional MRI sequences are limited in distinguishing infiltrating neoplasm from vasogenic edema. Advanced MRI sequences like Diffusion Weighted Imaging (DWI), Diffusion Tensor Imaging (DTI), Perfusion Weighted Imaging (PWI) and MR spectroscopy (MRS) have all been utilized for this aim with acceptable results. Other advanced MRI approaches, less explored for this task such as Arterial Spin Labelling (ASL), Diffusion Kurtosis Imaging (DKI), T2 relaxometry or Amide Proton Transfer (APT) are also showning promising results in this scenario. In this article, we will discuss the physiopathological basis of peritumoral T2/FLAIR signal abnormality and review potential applications of advanced MRI sequences for its evaluation.

Limited recurrence distance of glioblastoma under modern radiotherapy era

BACKGROUND

The optimal treatment volume for Glioblastoma multiforme (GBM) is still a subject of debate worldwide. The current study was aimed to determine the distances between recurring tumors and the edge of primary lesions, and thereby provide evidence for accurate target area delineation.

METHODS

Between October 2007 and March 2019, 68 recurrent patients with GBM were included in our study. We measured the distance from the initial tumor to the recurrent lesion of GBM patients by expanding the initial gross tumor volume (GTV) to overlap the center of recurrent lesion, with the help of the Pinnacle Treatment Planning System.

RESULTS

Recurrences were local in 47(69.1%) patients, distant in 12(17.7%) patients, and both in 9(13.2%) patients. Factors significantly influencing local recurrence were age (P = 0.049), sex (P = 0.049), and the size of peritumoral edema (P = 0.00). A total number of 91 recurrent tumors were analyzed. All local recurrences occurred within 2 cm and 94.8% (55/58) occurred within 1 cm of the original GTV based on T1 enhanced imaging. All local recurrences occurred within 1.5 cm and 98.3%(57/58) occurred within 0.5 cm of the original GTV based on T2-FLAIR imaging. 90.9% (30/33) and 81.8% (27/33) distant recurrences occurred >3 cm of T1 enhanced and T2-Flair primary tumor margins, respectively.

CONCLUSIONS

The 1 cm margin from T1 enhanced lesions and 0.5 cm margin from T2-Flair abnormal lesions could cover 94.8 and 98.3% local recurrences respectively, which deserves further prospective study as a limited but effective target area.

Peritumoral brain edema volume in meningioma correlates with tumor fractional anisotropy but not apparent diffusion coefficient or cerebral blood volume

PURPOSE

Pathogenesis of peritumoral brain edema (PTBE) in meningiomas remains unclear. Associations between PTBE volume and diffusion or perfusion properties of meningioma have not been studied. We aimed to investigate if diffusion and perfusion properties of meningioma correlate with its PTBE volume.

METHODS

Seventy consecutive patients (mean age, 58.9 ± 13.7 years; 37 women) with meningiomas who had preoperative DTI and DSC-PWI were retrospectively analyzed. PTBE volume, tumor volume, and mean T2 signal, ADC, FA, and CBV of the tumor were measured. Between meningiomas with and without PTBE, patient age and sex, as well as T2 signal intensity, volume, ADC, FA, and CBV of tumors, were compared. In meningiomas with PTBE, correlations of PTBE volume with patient age and sex, as well as T2 signal intensity, volume, ADC, FA, and CBV of tumors, were analyzed. Multivariable linear regression analysis was performed to identify factors associated with PTBE volume.

RESULTS

On univariable analysis, meningiomas without PTBE were more frequently found in women (P = 0.033) and demonstrated lower ADC (P = 0.020), higher FA (P < 0.001), and lower CBV (P < 0.001). PTBE volume of meningiomas correlated with tumor ADC (r = 0.444; P = 0.001), tumor FA (r = - 0.655; P < 0.001), and tumor CBV (r = 0.402; P = 0.003). On multivariable analysis, tumor FA was the only factor associated with PTBE volume (P < 0.001).

CONCLUSION

PTBE volume in meningioma correlates with tumor FA. DTI may help to understand the mechanism of PTBE in meningiomas.

Peritumoral edema in preoperative magnetic resonance imaging is an independent prognostic factor for hepatocellular carcinoma

BACKGROUND

Peritumoral edema is an independent prognostic risk factor for malignant tumors. Therefore, assessment of peritumoral edema in preoperative magnetic resonance imaging (MRI) may provide better prognostic information in patients with hepatocellular carcinoma (HCC).

AIM

To determine whether peritumoral edema in preoperative MRI is a prognostic factor for HCC.

METHODS

A retrospective analysis of 90 patients with HCC confirmed by surgical pathology was performed. All patients' peritumoral edema in preoperative MRI was reviewed by two radiologists. The association of disease recurrence with peritumoral edema and clinicopathological features was assessed using the Cox proportional hazards model. Interobserver agreement for evaluating peritumoral edema was determined using Cohen's κ coefficient.

RESULTS

Recurrence and non-recurrence after an average 20.8 month follow-up was 25.6% (23/90) and 74.4% (67/90), respectively. The ratio of peritumoral edema of 90 patients with HCC in preoperative MRI was 35.6% (32/90). In univariate Cox regression analysis, peritumoral edema [hazard ratio (HR) 11.08, P < 0.001], tumor diameter (HR 4.12, P = 0.001), microvascular invasion (HR 2.78, P = 0.020), gender (HR 0.29, P = 0.006), cirrhosis (HR 2.45, P = 0.049), ascites syndrome (HR 2.83, P = 0.022), aspartate aminotransferase(AST)/alanine aminotransferase(ALT) (HR 5.07, P = 0.003) were indicators for HCC recurrence. In multivariate Cox regression analysis, the tumor diameter (HR 2.53, P = 0.032) and peritumoral edema (HR 8.71, P < 0.001) were independent prognostic factors of HCC. The sensitivity, specificity, positive predictive value and negative predictive value of peritumoral edema and tumor diameter were 82.6%&60.9%, 80.6%&77.6%, 59.4%&48.3%, and 93.1%&85.3%, respectively.

CONCLUSION

Peritumoral edema in preoperative MRI may be considered as a biomarker of prognostic information for patients with HCC.

Correlation of apparent diffusion coefficient values and peritumoral edema with pathologic biomarkers in patients with breast cancer

PURPOSE

To investigate the relationship between breast cancer imaging features on magnetic resonance imaging (MRI) and histopathological characteristics.

METHODS AND MATERIALS

We prospectively enrolled 46 patients who underwent 1.5-T MRI with 68 breast malignant lesions from 2017 until 2019. Peritumoral edema was determined based on visual assessment on T2 weighted imaging. Lesions were categorized into two groups: A: with edema (48 lesions) and B: without edema (20 lesions).

RESULTS

The tumor size was not different among two groups but multifocal-multicentric lesions were more common in the group A (70% vs. 35%). The axillary lymph nodes are most involved in group A. ER and PR positive lesions were more common in group B (90% vs. 56.3%) but in the group A, HER2 positive lesions were found to be more common (31.3% vs. 15%). The mean ADC value in tumors and peritumoral regions were lower (0.97 × 10^-3 mm²/s, P = 0.023) and higher (1.85 × 10^-3 mm²/s, P < 0.0001) in group A, respectively. Peritumoral ADC value was significantly higher in HER2-positive group.

CONCLUSION

Breast carcinomas with peritumoral edema were found to be more multifocal-multicentric, with higher prevalence of axillary lymph node involvement, more HER 2-positive, with lower prevalence of ER/PR-positive, lower tumoral ADC and higher peritumoral ADC values.

The predominant expression of cancer stem cell marker ALDH1A3 in tumor infiltrative area is associated with shorter overall survival of human glioblastoma

Background

ALDH1A3 is a cancer stem cell marker in neoplasms including glioblastoma (GBM). However, the comprehensive role of ALDH1A3 in GBM remains unclear. This study attempted to investigate the expression of ALDH1A3 in human GBM tissues and its association with clinical parameters.

Methods

Thirty primary GBM and 9 control were enrolled in this study. ALDH1A3 mRNA and protein expression levels were detected by RT²-PCR and western blot, respectively. Immunohistochemistry and immunofluorescence staining were performed to evaluate the regional and cellular expression manner of ALDH1A3. The association of ALDH1A3 expression with multiple clinical parameters was analyzed.

Results

ALDH1A3 protein level, but not mRNA level, in a subgroup of GBM was significantly higher than that in the control group. ALDH1A3 immunoreactivity was detected heterogeneously in individual GBMs. Fifteen of 30 cases showed a positive of ALDH1A3 immunoreactivity which was predominantly observed in the tumor infiltrative area (TI). Double immunofluorescence staining revealed a co-localization of ALDH1A3 with GFAP in glial-shaped cells and in tumor cells. ALDH1A3 immunoreactivity was often merged with CD44, but not with CD68. Moreover, ALDH1A3 expression was positively associated with the tumor edema grade and inversely with overall survival (OS) (median OS: 16 months vs 10 months), but with neither MGMT promoter methylation status nor Ki67 index in GBM. An upregulation of ALDH1A3 was accompanied by a reduced expression of STAT3β and p-STAT3β.

Conclusions

Inter- and intra-tumoral heterogeneous expression of ALDH1A3 was exhibited in GBMs. A high immunoreactivity of ALDH1A3 in tumor infiltrative area was associated with shorter OS, especially in patients with MGMT promoter methylation. Our findings propose ALDH1A3 not only as a predictive biomarker but also as a potential target for personalized therapy of GBM.

Predictive factors for high-grade transformation in benign meningiomas

OBJECTIVE

Although they are generally slow-growing benign tumors, meningiomas may recur after surgery with transformation into atypical meningiomas. The purpose of this study was to investigate the radiological and histopathological factors that predict the risk of tumor progression from a benign to an atypical meningioma.

PATIENTS AND METHODS

All patients treated for recurrent meningiomas in whom the tumor showed histopathologically confirmed high-grade transformation (HGT) from a benign to an atypical meningioma between 2001 and 2017 were included. To evaluate the predictors of transformation, patient medical records documenting the diagnosis of a benign meningioma at the first surgery prior to second surgery with HGT were reviewed. Each patient was matched with four age- and sex-matched controls who were treated for a benign meningioma. The control group comprised all patients without any recurrence for at least 60 months.

RESULTS

Fourteen patients with benign meningioma underwent HGT and were included. The median time interval of transformation was 63 months (range, 19-132 months). Multivariate analysis indicated that an increased mitotic index (odds ratio [OR], 10.409; 95 % confidence interval [CI], 1.297-83.549; P = 0.027) was a significant predictor of transformation. Prominent peritumoral edema (OR, 33.822; 95 % CI, 0.935-223.688; P = 0.054) did not reach the statistical significance.

CONCLUSION

An increased mitotic index may be used as the predictor for HGT of benign meningiomas. Although these tumors with a high risk for transformation do not meet the diagnostic criteria for atypical meningiomas, they may require more attentive observation and management than other benign meningiomas.

Laser Interstitial Thermotherapy for Treatment of Symptomatic Peritumoral Edema After Radiosurgery for Meningioma

BACKGROUND

Symptomatic peritumoral edema (PTE) is a known complication after radiosurgical treatment of meningiomas. Although the edema in most patients can be successfully managed conservatively with corticosteroid therapy or bevacizumab, some medically refractory cases may require surgical resection of the underlying lesion when feasible. Laser interstitial thermotherapy (LITT) continues to gain traction as an effective therapeutic modality for the treatment of radiation necrosis where its biggest impact is through the control of peritumoral edema.

CASE DESCRIPTION

A 56-year-old woman with neurofibromatosis 2 presented with a symptomatic, regrowing left frontotemporal lesion that had previously been radiated, then resected with confirmed recurrence of grade I meningioma, and subsequently radiated again for lesion recurrence. Given her history of 2 prior same-side craniotomies, including a complication of wound infection, she was not a candidate for further open surgical resection. Having failed conservative management, she underwent LITT with intraoperative biopsy demonstrating viable grade I meningioma. Postoperatively, she demonstrated radiographic marked, serial reduction of PTE and experienced resolution of her symptoms.

CONCLUSIONS

This case demonstrates that LITT may be a viable alternative treatment for patients with meningioma with symptomatic PTE who have failed medical therapy and require surgical intervention.

Cerebral metastases: do size, peritumoral edema, or multiplicity predict infiltration into brain parenchyma?

BACKGROUND

Brain metastases (BMs) are the most frequent malignancy of the central nervous system. Previous research suggested that some metastases show infiltrative behavior rather than sharp demarcation. We hypothesized that three magnetic resonance (MR) imaging parameters-(a) tumor size, (b) extent of peritumoral edema, and (c) presence of multiple BMs-are predictors of cellular invasion beyond the surgically identifiable tumor margins.

METHODS

We performed a post hoc analysis on prospectively collected data of patients with BMs. Biopsies beyond the resection margin and immunohistochemistry were performed to assess infiltration status. The three MR imaging parameters were dichotomized into diameters ≤ 30 mm ("small") and > 30 mm ("large"), amount of peritumoral edema "extended" and "limited," and "multiple BMs" and "single BMs," respectively. The association between infiltration status and imaging parameters was calculated using chi-square test.

RESULTS

Biopsy beyond the resection margin was performed in 77 patients; 49 (63.6%) had supramarginal infiltration and 28 patients (36.4%) showed no infiltration. Histological evidence of tumor infiltration was found in 25/41 patients with smaller lesions (61%) and in 24/36 with larger lesions (66.7%, p = 0.64), in 28/44 patients with limited (63.6%) and in 21/33 patients with extended edema (63.6%, p = 1.0), in 28/45 patients (62.2%) with single BM and in 21/32 patients (65.6%) with multiple BMs (p = 0.81).

CONCLUSIONS

Based on the post hoc analysis of our prospective trial data, we could not confirm the hypothesis that infiltration of brain parenchyma beyond the glial pseudocapsule is associated with the MR imaging parameters tumor size, extent of edema, or multiplicity of metastases.

Progesterone Is More Effective Than Dexamethasone in Prolonging Overall Survival and Preserving Neurologic Function in Experimental Animals with Orthotopic Glioblastoma Allografts

OBJECTIVE

Dexamethasone (DEXA) has been widely used in the management of peritumoral brain edema. DEXA, however, has many systemic side effects and can interact negatively with glioma therapy. Progesterone (PROG), however, is a well-tolerated and readily accessible anti-inflammatory and antiedema agent, with potent neuroprotective properties. We investigated whether PROG could serve as a viable alternative to DEXA in the management of peritumoral brain edema.

METHODS

We used an orthotopic C6 glioblastoma model with male Sprague-Dawley rats. Tumor grafts were allowed to grow for 14 days before drug treatment with DEXA 1 mg/kg, PROG 10 mg/kg, or PROG 20 mg/kg for 5 consecutive days. The overall animal survival and neurologic function were evaluated. Mechanistic studies on blood-brain barrier permeability and angiogenic responses were performed on the ex vivo tumor grafts.

RESULTS

We found that all drug treatments prolonged overall survival to different extents. PROG 10 mg led to significantly longer survival and better preservation of neurologic function and body weight. The blood-brain barrier permeability was better preserved with PROG 10 mg than with DEXA, possibly through downregulation of matrix metalloproteinase-9 and aquaporin-4 expression. Antiangiogenic responses were also observed in the PROG group.

CONCLUSIONS

The present proof-of-concept pilot study has provided novel information on the use of PROG as a corticosteroid-sparing agent in brain tumor management. Further translational and clinical studies are warranted.

Differentiation of brain tumor-related edema based on 3D T1rho imaging

BACKGROUND AND PURPOSE

Cerebral edema associated with brain tumors is an important source of morbidity. Its type depends largely on the capillary ultra-structures of the histopathologic subtype of underlying brain tumor. The purpose of our study was to differentiate vasogenic edema associated with brain metastases and infiltrative edema related to diffuse gliomas using quantitative 3D T1 rho (T1ρ) imaging.

MATERIALS AND METHODS

Preoperative MR examination including whole brain 3D T1ρ imaging was performed in 23 patients with newly diagnosed brain tumors (9 with metastasis, 8 with lower grade glioma, LGG, 6 with glioblastoma, GBM). Mean T1ρ values were measured in regions of peritumoral non-enhancing T2 signal hyperintensity, excluding both enhancing and necrotic or cystic component, and normal-appearing white matter.

RESULTS

Mean T1ρ values were significantly elevated in the vasogenic edema surrounding intracranial metastases when compared to the infiltrative edema associated with either LGG or GBM (p=0.02 and <0.01, respectively). No significant difference was noted between T1ρ values of infiltrative edema between LGG and GBM (p=0.84 and 0.96, respectively).

CONCLUSION

Our study demonstrates the feasibility and potential diagnostic role of T1ρ in the quantitative differentiation between edema related to intracranial metastases and gliomas and as a potentially complementary tool to standard MR techniques in further characterizing pathophysiology of vasogenic and infiltrative edema.

Perilesional edema in brain metastasis from non-small cell lung cancer (NSCLC) as predictor of response to radiosurgery (SRS)

Radiosurgery (SRS) is widely used in the treatment of brain oligo-metastases from NSCLC. The aim of present study is to evaluate the extent of perilesional edema in brain metastases as predictive factor of treatment response. This single center retrospective study included 42 consecutive patients (January 2011-December 2014) with 1-2 brain metastasis from NSCLC treated with Radiosurgery (SRS). Extent of perilesional edema was measured as maximal extension from the edge of lesion and classified as minor (<10 mm) or major (≥10 mm). We analyzed Modality of Brain Recurrence (MBR), classified as in-field or out-of- field, and Brain Progression Free-Survival (BPFS) after treatment stratified according to extent of perilesional edema. Analyzing modality of brain recurrence and BPFS, after a median follow-up of 6 months, we found that patients with minor edema had a better radiological response to SRS with none in-field recurrences and a lower risk of the onset of new brain lesions (out-of-field recurrence). Instead, patients group with major edema had a worse response rate of lesions treated, further, a higher risk of out-of-field brain relapse. Extent of perilesional edema in brain metastasis from NSCLC could be a predictive factor of response and brain progression after SRS treatment alone.

The relationship between MRI quantitative parameters and the expression of hypoxia inducible factor-1 alpha in cerebral astrocytoma

OBJECTIVE

Astrocytoma is the common type of glioma. But the MRI scanning for astrocytoma preoperation pathological diagnosis is not exact. The purpose of this study was to use the MRI multi quantitative parameters to improve the diagnosis of astrocytoma and exploit their molecular mechanism related to the expression of HIF-1α.

METHODS

Superconducting MR scanner and its work station were used to calculate the MRI multi quantitative parameters of the selected patients in this experiment. Scion Image Beta4.03 software was used to get the cellular density of tumor tissue. The expression of HIF-1α in astrocytoma specimens was detected by immunohistochemistry method. The correlation of MRI multi quantitative parameters and the expression of HIF-1α was analyzed by statistical software.

RESULT

The values of ADC, RSIGd, EP, EI, cellular density and the expression of HIF-1α were changed with the malignant degree of astrocytoma to some extent, but not every quantitative parameter was related to the expression of HIF-1α.

CONCLUSION

The MRI multi quantitative parameters binding with conventional MRI imaging can significantly raise the diagnostic accuracy of astrocytoma preoperatively. MRI features could indirectly reflect the biological behavior of astrocytoma. The peritumoral edema can't be explained by only one theory.

Relationship Between Cytogenetic Complexity and Peritumoral Edema in High-Grade Astrocytoma

BACKGROUND

The purpose of the study is to reveal the association of cytogenetic compltyexi and peritumoral edema volume (PTEV) and its prognostic significance in high-grade astrocytoma patients by culturing patient tumor cells.

METHODS

Twenty-seven high-grade astrocytoma patients were divided into three groups according to karyotype complexity: normal, non-complex karyotype (NCK), and complex karyotype (CK). Endothelial growth factor receptor (EGFR) amplification was detected by FISH, and its association with chromosome 7 abnormalities was analyzed. Mean PTEV of each group was compared by ANOVA to evaluate the relationship between PTEV and cytogenetic complexity.

RESULTS

The PTEV of patients in normal (n=6), NCK (n=8), and CK (n=13) groups were 24.52±17.73, 34.26±35.04, and 86.31±48.7 cm³, respectively (P=0.005). Ten out of 11 patients with EGFR amplification showed abnormalities in chromosome 7. The mean PTEV of EGFR-amplified and non-amplified groups were 80.4±53.7 and 41.3±37.9 cm³, respectively (P=0.035). The average survival of patients with PTEV less than 90 cm³ was 30.52±26.11 months, while in patients with PTEVs over or equal to 90 cm³, it was 10.83±5.53 months (P=0.007).

CONCLUSIONS

The results show an association of complex karyotype with the PTEV of high-grade astrocytoma. EGFR amplification plays a significant role in the formation of peritumoral edema, causing PTEV to increase, which is related with survival. This implies that cytogenetic karyotype can be applied as a prognostic factor.

Corticospinal tract modeling for neurosurgical planning by tracking through regions of peritumoral edema and crossing fibers using two-tensor unscented Kalman filter tractography

PURPOSE

The aim of this study was to present a tractography algorithm using a two-tensor unscented Kalman filter (UKF) to improve the modeling of the corticospinal tract (CST) by tracking through regions of peritumoral edema and crossing fibers.

METHODS

Ten patients with brain tumors in the vicinity of motor cortex and evidence of significant peritumoral edema were retrospectively selected for the study. All patients underwent 3-T magnetic resonance imaging (MRI) including functional MRI (fMRI) and a diffusion-weighted data set with 31 directions. Fiber tracking was performed using both single-tensor streamline and two-tensor UKF tractography methods. A two-region-of-interest approach was used to delineate the CST. Results from the two tractography methods were compared visually and quantitatively. fMRI was applied to identify the functional fiber tracts.

RESULTS

Single-tensor streamline tractography underestimated the extent of tracts running through the edematous areas and could only track the medial projections of the CST. In contrast, two-tensor UKF tractography tracked fanning projections of the CST despite peritumoral edema and crossing fibers. Based on visual inspection, the two-tensor UKF tractography delineated tracts that were closer to motor fMRI activations, and it was apparently more sensitive than single-tensor streamline tractography to define the tracts directed to the motor sites. The volume of the CST was significantly larger on two-tensor UKF than on single-tensor streamline tractography ([Formula: see text]).

CONCLUSION

Two-tensor UKF tractography tracks a larger volume CST than single-tensor streamline tractography in the setting of peritumoral edema and crossing fibers in brain tumor patients.

Reconstruction of the arcuate fasciculus for surgical planning in the setting of peritumoral edema using two-tensor unscented Kalman filter tractography

Background

Diffusion imaging tractography is increasingly used to trace critical fiber tracts in brain tumor patients to reduce the risk of post-operative neurological deficit. However, the effects of peritumoral edema pose a challenge to conventional tractography using the standard diffusion tensor model. The aim of this study was to present a novel technique using a two-tensor unscented Kalman filter (UKF) algorithm to track the arcuate fasciculus (AF) in brain tumor patients with peritumoral edema.

Methods

Ten right-handed patients with left-sided brain tumors in the vicinity of language-related cortex and evidence of significant peritumoral edema were retrospectively selected for the study. All patients underwent 3-Tesla magnetic resonance imaging (MRI) including a diffusion-weighted dataset with 31 directions. Fiber tractography was performed using both single-tensor streamline and two-tensor UKF tractography. A two-regions-of-interest approach was applied to perform the delineation of the AF. Results from the two different tractography algorithms were compared visually and quantitatively.

Results

Using single-tensor streamline tractography, the AF appeared disrupted in four patients and contained few fibers in the remaining six patients. Two-tensor UKF tractography delineated an AF that traversed edematous brain areas in all patients. The volume of the AF was significantly larger on two-tensor UKF than on single-tensor streamline tractography (p < 0.01).

Conclusions

Two-tensor UKF tractography provides the ability to trace a larger volume AF than single-tensor streamline tractography in the setting of peritumoral edema in brain tumor patients.

•

We compared two tractography methods in datasets from 10 brain tumor patients.

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All patients had peritumoral edema affecting the arcuate fasciculus (AF), a fiber tract related to language function.

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AF volume from unscented Kalman filter (UKF) two-tensor tractography was larger than in standard DTI tractography.

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Two-tensor UKF tractography may trace the AF more completely in patients with peritumoral edema.

Radiation-induced intratumoral necrosis and peritumoral edema after gamma knife radiosurgery for intracranial meningiomas

Objective

To study the clinical significance and relevant factors of radiation-induced intratumoral necrosis (RIN) and peritumoral edema (PTE) after Gamma knife radiosurgery (GKRS) for intracranial meningiomas.

Methods

We retrospectively analyzed the data of 64 patients who underwent GKRS for intracranial meningioma. The mean lesion volume was 4.9 cc (range, 0.3-20), and the mean prescription dose of 13.4 Gy (range, 11-18) was delivered to the mean 49.9% (range, 45-50) isodose line. RIN was defined as newly developed or enlarged intratumoral necrosis after GKRS.

Results

RIN and new development or aggravation of PTE were observed in 21 (32.8%) and 18 (28.1%) cases of meningioma, respectively during the median follow-up duration of 19.9±1.0 months. Among various factors, maximum dose (>25 Gy) and target volume (>4.5 cc) were significantly related to RIN, and RIN and maximum dose (>24 Gy) were significantly related to the development or aggravation of PTE. In 21 meningiomas with development of RIN after GKRS, there was no significant change of the tumor volume itself between the times of GKRS and RIN. However, the PTE volume increased significantly compared to that at the time of GKRS (p=0.013). The median interval to RIN after GKRS was 6.5±0.4 months and the median interval to new or aggravated PTE was 7.0±0.7 months.

Conclusion

A close observation is required for meningiomas treated with a maximum dose >24 Gy and showing RIN after GKRS, since following or accompanying PTE may deteriorate neurological conditions especially when the location involves adjacent critical structures.