Relationship of intraoperative ultrasound characteristics with pathological grades and Ki-67 proliferation index in intracranial gliomas

A Brief Explanation on Surgical Approaches for Treatment of Different Brain Tumors

The main goal of brain tumor surgery is to achieve gross total tumor resection without postoperative complications and permanent new deficits. However, when the lesion is located close or within eloquent brain areas, cranial nerves, and/or major brain vessels, it is imperative to balance the extent of resection with the risk of harming the patient, by following a so-called maximal safe resection philosophy. This view implies a shift from an approach-guided attitude, in which few standard surgical approaches are used to treat almost all intracranial tumors, to a pathology-guided one, with surgical approaches actually tailored to the specific tumor that has to be treated with specific dedicated pre- and intraoperative tools and techniques. In this chapter, the basic principles of the most commonly used neurosurgical approaches in brain tumors surgery are presented and discussed along with an overview on all available modern tools able to improve intraoperative visualization, extent of resection, and postoperative clinical outcome.

Development of a Standardized Semantic Feature-Based Reporting Proforma for Intraoperative Ultrasound Findings in Brain Tumors and Application in High-Grade Gliomas - A Preliminary Study

Purpose A semantic feature-based reporting proforma for intraoperative ultrasound findings in brain tumors was devised to standardize reporting. It was applied as a pilot study on a cohort of histologically confirmed high-grade supratentorial gliomas (Grade 3 and 4) for internal validation.

Materials and Methods This intraoperative semantic ultrasound proforma was used to evaluate 3D ultrasound volumes using Radiant DICOM software by 3 surgeons. The ultrasound semantic features were correlated with histological features like tumor grade, IDH status, and MIB index.

Results 68 patients were analyzed using the semantic proforma. Irregular crenated was the most common margin (63.2%) and lesions were heterogeneously hyperechoic (95.6%). Necrosis was commonly seen and noted as single (67.6%) or multiple (13.2%) in over 80% cases. A separate perilesional zone, which was predominantly hyperechoic in 41.8% and both hypo and hyperechoic in 12.7%, could be identified in 54.5% of cases. Grade 4 tumors were more likely to have an irregular crenated margin (71.2%) with a single large area of necrosis, while Grade 3 tumors were likely to have smooth (31.3%) or non-characterizable margins (31.2%) with no or multiple areas of necrosis. IDH-negative tumors were more likely to have a single large focus of necrosis. Among the GBMs (52 cases), MIB labelling index of>15% was associated with poorly delineated, uncharacterizable margins, when compared with MIB labelling index<15% (23.5 vs. 0%), (p=0.046).

Conclusion A detailed semantic proforma was developed for brain tumors and was internally validated. A few ultrasound sematic features were identified correlating with histological features in high-grade gliomas. It will require further external validation for refinement and acceptability.

Relationship Between Ultrasound Features and Ki-67 Labeling Index of Soft Tissue Sarcoma

Objectives

To explore the relationship between ultrasound (US) features and Ki-67 labeling index (LI) of soft tissue sarcoma (STS).

Methods

Forty-six patients with 47 STS lesions, between September 2014 and April 2020, were enrolled in the study. Point-biserial correlation analysis and Spearman’s correlation analysis were utilized to examining the relationship between the US features and the Ki-67 LI of STS. The differences of US features between high and low Ki-67 proliferation groups were statistically analyzed by independent t test, Wilcoxon rank-sum test, and Fisher’s exact test. The optimal cut-off points of US features revealing significant differences were estimated by the maximum Youden index.

Results

A moderate correlation between the vascular density grade and the Ki-67 LI (ρ = 0.409, P = 0.004) was found in this study. In addition, other ultrasound features were irrelevant to the Ki-67 LI. The cut-off for differentiating low- and high-proliferation groups was grade II according to the best Youden index. The area under receiver operating characteristic (ROC) curve was 0.74 (p = 0.011) with a sensitivity of 60.6% and specificity of 78.6%.

Conclusions

Only the vascular density grade of STS had a weak positive correlation with Ki-67 LI, and might be capable of predicting the proliferation of STS. Other ultrasonographic features of STS such as shape and tumor margin have no correlation with Ki-67 LI.

Is Ki-67 index overexpression in IDH wild type glioblastoma a predictor of shorter Progression Free survival? A clinical and Molecular analytic investigation

BACKGROUND

Ki-67 proliferation index is widely used for differentiating between high and low-grade gliomas, but differentiating between the same grade IV appears to be more problematic, and the point about its prognostic value for GBM patients remains unclear. To reduce the possibility to find a marked histological heterogeneity, and may contain areas that could be diagnosed as lower grade, in this study we considered a large group of patients with IDH wild-type Glioblastoma (IDH-WT GBM) and we have analyzed previously reported prognostic factors, in regards to their relationship with the Ki-67 expression index.

METHODS

We explore the prognostic impact of ki-67 index status in 127 patients affected by IDH-WT GBM. We therefore analyzed clinical characteristics, tumor genetics, dimension and clinical outcomes. We selected a total of 127 patients affected by newly diagnosed IDH-WT GBM who underwent surgery, radiation, and chemotherapy in our Institution in the period ranging between January 2014 and December 2016 RESULTS: The volume of the lesion had a strong association with the Ki67 overexpression. In particular lesions whose volume was greater than 45  cm³, presented a higher percentage of Ki67 expression demonstrating that greater tumors are more likely associated to higher values of Ki67 percentages. On a multivariate analysis, it was possible to outline that Ki67 was significant a predictor of shorter PFS independently from the age of the patients, the volume of the lesion and preoperative KPS.

CONCLUSIONS

There is a correlation between percentage staining of Ki-67 and OS in our cohort of patients with IDH-WT GBM. This is only the third observational study documenting a positive correlation between Ki-67 and overall survival in GBM and the first one demonstrates that percentage Ki-67 staining >20 % predicts poorer progression free survival in IDH-WT GBM.

New Hope in Brain Glioma Surgery: The Role of Intraoperative Ultrasound. A Review

Maximal safe resection represents the gold standard for surgery of malignant brain tumors. As regards gross-total resection, accurate localization and precise delineation of the tumor margins are required. Intraoperative diagnostic imaging (Intra-Operative Magnetic Resonance-IOMR, Intra-Operative Computed Tomography-IOCT, Intra-Operative Ultrasound-IOUS) and dyes (fluorescence) have become relevant in brain tumor surgery, allowing for a more radical and safer tumor resection. IOUS guidance for brain tumor surgery is accurate in distinguishing tumor from normal parenchyma, and it allows a real-time intraoperative visualization. We aim to evaluate the role of IOUS in gliomas surgery and to outline specific strategies to maximize its efficacy. We performed a literature research through the Pubmed database by selecting each article which was focused on the use of IOUS in brain tumor surgery, and in particular in glioma surgery, published in the last 15 years (from 2003 to 2018). We selected 39 papers concerning the use of IOUS in brain tumor surgery, including gliomas. IOUS exerts a notable attraction due to its low cost, minimal interruption of the operational flow, and lack of radiation exposure. Our literature review shows that increasing the use of ultrasound in brain tumors allows more radical resections, thus giving rise to increases in survival.

Molecular pathological expression in malignant gliomas resected by fluorescein sodium-guiding under the YELLOW 560 nm surgical microscope filter

Background

This study aimed to analyze the relationship between molecular pathologic expression of GFAP and Ki-67 and fluorescence levels, and to provide molecular pathological basis for the removal of malignant gliomas (MG) by Fluorescein Sodium (FLS) navigation under the YELLOW 560 nm surgical microscope filter.

Methods

A retrospective analysis of clinical data of 18 MG cases confirmed by the postoperative pathology was performed. All cases were resected by FLS guiding under the YELLOW 560 nm filter. Hematoxylin-eosin (HE) staining, molecular pathology markers GFAP, and Ki-67 immunohistochemical staining of the specimens were performed. The relationship between fluorescence staining levels and GFAP positive rate, Ki-67 proliferation index, and WHO grades was studied.

Results

There were 69 pathological specimens with fluorescence levels of “bright” fluorescence (n = 32), “low” fluorescence (n = 18), and “no” fluorescence (n = 19). Immunohistochemical staining showed GFAP-positive expression in both tumor cells and normal glial cells. The staining levels of the specimens in the fluorescence regions were higher than that in the non-fluorescence regions. GFAP expression was positive in 61 specimens and negative in 8 specimens. Comparison of Ki-67 proliferation index using chi-square test showed different fluorescence levels had different Ki-67 proliferation indexes (χ² = 14.678, p = 0.005). With high proliferation index of specimens, fluorescence level was brighter. WHO grade had no correlation with fluorescence levels (χ² = 3.531, p = 0.171).

Conclusion

FLS-guided resection of MG is safe and effective. In the boundary area of MG, fluorescence levels and Ki-67 proliferation index showed correlation. FLS-guided resection achieved the function of “reducing tumor cell,” thus reducing the proliferation index in the lesion area.