Pineal Tumor Surgery-The Choice of the Approach Related to Tumor Characteristics and Posterior Fossa Anatomy.

OBJECTIVE: This research aimed to determine whether an adequate surgical approach can be chosen based on clearly defined values of anatomical landmarks (tentorial angle) and tumor size and extension. METHODS: We conducted a retrospective analysis of patients operated on because of pineal tumors. The cohort was divided depending on the surgical approach. On preoperative magnetic resonance imaging, we measured maximal diameters, tumor volume, and tumor propagation. In the group of patients operated with the supracerebellar infratentorial approach, we also tested the correlation of tentorial angle with residual tumor. Differences among groups in resection, complications rate, and outcome were tested by the χ2 test. Finally, in both groups, the correlation of residual tumor with tumor volume, propagation, and diameters was tested using the receiver operating characteristic curve. RESULTS: In the group operated with a supracerebellar approach, total resection was achieved in 78% of the patients. The critical value of cranio-caudal diameter correlated with tumor residue was 31 mm, for lateral-lateral diameter 25 mm, for the lateral extension 14 mm, and tumor volume 12 cm3. Tentorial angle did not influence the extent of the resection. In the group operated with an occipital transtentorial approach, the critical tumor volume related to tumor residue was 9 mm3, anterior-posterior diameter 29 mm, and cranio-caudal diameter 28 mm. The extent of the resection was significantly higher in the supracerebellar group. CONCLUSIONS: In both approaches, tumors larger than 3 cm show an increased risk of subtotal resection. Except when most tumor volume is localized above the venous system, we advocate a supracerebellar corridor as an effective approach that is not limited by tentorial angle.

Oncogene-induced senescence in meningiomas-an immunohistochemical study.

PURPOSE: Meningiomas are tumours originating from meningothelial cells, the majority belonging to grade 1 according to the World Health Organization classification of the tumours of the Central Nervous System. Factors contributing to the progression to the higher grades (grades 2 and 3) have not been elucidated yet. Senescence has been proposed as a potential mechanism constraining the malignant transformation of tumours. Senescence-associated beta-galactosidase (SA-ß-GAL) and inhibitors of cyclin-dependent kinases p16 and p21 have been suggested as senescence markers. METHODS: We analysed 318 meningiomas of total 343 (178 grade 1, 133 grade 2 and 7 grade 3). Tissue microarrays were constructed and stained immunohistochemically, using antibodies for SA-ß-GAL, p16 and p21. RESULTS: The positive correlation of the tumour grade with the expression of p16 (p = 0.016) and SA-ß-GAL (p = 0.002) was observed. The expression of p16 and SA-ß-GAL was significantly higher in meningiomas grade 2 compared to meningiomas grade 1 (p = 0.006 and p = 0.004, respectively). SA-ß-GAL positivity positively correlated with p16 and p21 in the whole cohort. In grade 2 meningiomas, a positive correlation was only between SA-ß-GAL and p16. Correlations of senescence markers in meningiomas grade 2 were not present. CONCLUSION: Our findings suggest the senescence activation in meningiomas grade 2 as a potential mechanism for the restraining of tumour growth and give hope for applying of promising senolytic therapy.

Germline Variants in Cancer Predisposition Genes in Pediatric Patients with Central Nervous System Tumors.

Central nervous system (CNS) tumors comprise around 20% of childhood malignancies. Germline variants in cancer predisposition genes (CPGs) are found in approximately 10% of pediatric patients with CNS tumors. This study aimed to characterize variants in CPGs in pediatric patients with CNS tumors and correlate these findings with clinically relevant data. Genomic DNA was isolated from the peripheral blood of 51 pediatric patients and further analyzed by the next-generation sequencing approach. Bioinformatic analysis was done using an "in-house" gene list panel, which included 144 genes related to pediatric brain tumors, and the gene list panel Neoplasm (HP:0002664). Our study found that 27% of pediatric patients with CNS tumors have a germline variant in some of the known CPGs, like ALK, APC, CHEK2, ELP1, MLH1, MSH2, NF1, NF2 and TP53. This study represents the first comprehensive evaluation of germline variants in pediatric patients with CNS tumors in the Western Balkans region. Our results indicate the necessity of genomic research to reveal the genetic basis of pediatric CNS tumors, as well as to define targets for the application and development of innovative therapeutics that form the basis of the upcoming era of personalized medicine.

A potential role of mechano-gated potassium channels in meningioma-related seizures.

Every third patient with intracranial meningioma develops seizures of poorly understood etiology. Tumor and peritumoral edema may exert mechanical pressure on the cortex that may affect mechano-gated potassium channels - KCNK2 and KCNK4. These channels regulate neuron excitability and have been related to seizures in some other conditions. The objective of the present study was to explore a potential relation between the levels of these proteins in tumor tissue and adjacent cortex and seizures development. The study included 19 meningioma patients that presented one or more preoperative seizures and 24 patients with no seizures. Tissue samples were collected in the course of surgical removal of the meningioma. Postoperative seizure freedom was achieved in 11 out of 19 patients. The relative level of KCNK2 in the cortical tissue was lower in patients with preoperative seizures. On the other hand, cortical tissue level of KCNK4 was higher in patients that became seizure-free after the surgery. In addition, relative levels of KCNK4 in the cortical and tumor tissue appear to be lowered by the treatment with anti-seizure medication levetiracetam. These results imply that KCNK2 and KCNK4 may be involved in the development of meningioma-related seizures and may represent promising therapeutic targets.

Reconstruction of Moderately and Severely Atrophic Scalp-A Multicentric Experience in Surgical Treatment of Patients Irradiated for Tinea Capitis in Childhood and Surgical Algorithm.

Background and Objectives: Before the introduction of griseofluvin, the use of X-ray radiation was the treatment of choice for tinea capitis. More than half a century later various types of tumors have been found to be associated with childhood irradiation due to tinea capitis, most commonly cancers of the head and neck, as well as brain tumors. The often unusually aggressive and recurrent nature of these tumors necessitates the need for repeated surgeries, while the atrophic skin with an impaired vascular supply due to radiation often poses an additional challenge for defect reconstruction. We present our experience in the surgical treatment of such patients. Materials and Methods: This is a retrospective cohort study. In this study, 37 patients treated for acquired defects of the scalp with a history of irradiation therapy due to tinea capitis in childhood were included in this study, 24 male and 13 female patients. The mean age at the first appointment was 60.6 ± 7.8, with the youngest included patient being 46 and the oldest being 75 years old. Patients' characteristics, surgical treatment, and complications were analyzed and a reconstructive algorithm was developed. Results: Local flaps were used for reconstruction in 34 patients, direct sutures were used in 10 patients and 20 patients received split-thickness skin grafts for coverage of both primary and secondary defects for reconstruction of flap donor sites. One regional flap and one dermal substitute covered by an autologous skin graft were also used for reconstruction. Complications occurred in 43.2% of patients and were significantly associated with the presence of comorbidities (p = 0.001), aseptic bone necrosis (p = 0.001), as well as skin atrophy in frontal, occipital, and parietal region (p = 0.001, p = 0.042 and p = 0.001, respectively). A significant correlation between major complications and moderate skin atrophy was found only in the parietal region (p = 0.026). Conclusions: Unfortunately, many protocols developed for scalp reconstruction are not applicable in the setting of severe or diffuse scalp skin atrophy associated with high tumor recurrence rate and radiation-induced vascular impairment, such as in tinea capitis patients in Serbia. An algorithm has been developed based on the authors' experience in managing these patients.

Proapoptotic and proautophagy effect of H1-receptor antagonist desloratadine in human glioblastoma cell lines.

Glioblastomas are aggressive and usually incurable high-grade gliomas without adequate treatment. In this study, we aimed to investigate the potential of desloratadine to induce apoptosis/autophagy as genetically regulated processes that can seal cancer cell fates. All experiments were performed on U251 human glioblastoma cell line and primary human glioblastoma cell culture. Cytotoxic effect of desloratadine was investigated using MTT and CV assays, while oxidative stress, apoptosis, and autophagy were detected by flow cytometry and immunoblot. Desloratadine treatment decreased cell viability of U251 human glioblastoma cell line and primary human glioblastoma cell culture (IC50 value 50 µM) by an increase of intracellular reactive oxygen species and caspase activity. Also, desloratadine decreased the expression of main autophagy repressor mTOR and its upstream activator Akt and increased the expression of AMPK. Desloratadine exerted dual cytotoxic effect inducing both apoptosis- and mTOR/AMPK-dependent cytotoxic autophagy in glioblastoma cells and primary glioblastoma cell culture.

A unique case of intracranial collision tumor composed of ganglioglioma WHO gr I and supratentorial ependymoma WHO gr III: case-based literature review.

PURPOSE: Intracranial collision tumor is a rare entity that represents the coexistence of two histopathological different tumor types in the same area without histological admixture or an intermediate cell population zone. So far, several cases of collision tumors with ganglioglioma as its component have been reported in the literature, while supratentorial ependymoma has never been reported as a collision tumor component. We are presenting a unique case of collision tumor in patient without previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis. METHODS AND RESULTS: A 17-year-old male with no previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis was presented to our clinic with grand mal seizure. Brain magnetic resonance imaging with gadolinium contrast was done revealing a contrast-enhancing lesion of right frontal lobe closely related to dura, surrounded by perifocal edema. The patient underwent a gross total tumor resection. Histological examination revealed collision tumor with two distinct components: ganglioglioma and supratentorial ependymoma. CONCLUSION: To our best knowledge, no previous reports of collision tumor composed of ganglioglioma and supratentorial ependymoma in a single patient have been reported. We believe that this report could significantly contribute to further surgical practice as well as to treatment decision for these types of collision tumors.

Total diagnostic interval in children with brain tumours in a middle-income country: national experience from Serbia.

PURPOSE: The aim was to evaluate the total diagnostic interval (TDI) and presenting complaints in children with brain tumours in Serbia. METHODS: This study retrospectively analysed 212 children aged 0-18 years newly diagnosed with brain tumours in two tertiary centres from mid-March 2015 to mid-March 2020 covering virtually all children with brain tumours in Serbia. TDI was calculated as the difference between the date of diagnosis and the date of symptom onset presented as a median in weeks. This variable has been evaluable for 184 patients. RESULTS: Overall TDI was 6 weeks. TDI was significantly longer in patients with low-grade tumours (11 weeks) than in patients with high-grade tumours (4 weeks). Children with the most frequent complaints (headache, nausea/vomiting and gait disturbance) were more likely to be diagnosed sooner. Patients with a single complaint had significantly longer TDI (12.5 weeks) contrasted to patients with multiple complaints (5 weeks). CONCLUSION: TDI with a median of 6 weeks is similar to other developed countries. Our study supports the view that low-grade tumours will present later than high-grade tumours. Children with the commonest complaints and children with multiple complaints were more likely to be diagnosed sooner.

Factors associated with preoperative and early and late postoperative seizures in patients with supratentorial meningiomas.

OBJECTIVE: Risk factors for epilepsy in meningioma patients are not yet clearly defined, however, seizure freedom is a significant factor for quality of life after surgery. METHODS: We performed a retrospective study of the 333 adult patients who received surgery for supratentorial meningioma at our center. Various clinical, radiological, and surgical variables were included in the multivariate regression, and the outcomes measured were the occurrence of seizure(s) preoperatively, during the hospitalization, and during the follow-up period. RESULTS: A total of 89 (26.7%) patients experienced preoperative seizures, of whom 62.9% were seizure free after the surgery. Of 244 patients without epilepsy before surgery, 11.9% had at least one seizure postoperatively. In total, 63 of our patients (18.9%) experienced seizures after the surgery, of whom 20 had refractory epilepsy. Multivariate analysis identified the following predictors of preoperative seizures: the absence of headache (OR: 0.23, CI: 2.55-8.50), the presence of significant peritumoral edema (OR: 4.35, CI: 2.57-7.35), and younger age (OR: 0.97 per year increase, CI: 0.95-0.99). Factors associated with early postoperative seizures were: younger age (OR: 0.96 per year increase, CI: 0.93-0.99) and the presence of preoperative seizures (OR: 2.73, CI: 1.13-6.57), while the presence of preoperative seizures (OR: 4.73, CI: 2.05-10.92), tumor progression (OR: 5.38, CI: 2.25-12.89), and neurological worsening (OR: 5.21 CI: 1.72-15.81) were significant for late postoperative seizures. SIGNIFICANCE: Our results from a single-center meningioma cohort confirm, in general, data from some previous studies regarding patients' characteristics for both preoperative and overall postoperative epilepsy. Besides previously described risk factors, younger age was important for preoperative and early postoperative seizures. Epilepsy is common in patients with recurrence of meningioma, but the variables of significance for refractory seizures in these patients require further examination.

Association between microRNAs 10b/21/34a and acute toxicity in glioblastoma patients treated with radiotherapy and temozolomide.

A personalized approach to chemoradiation is important in reducing its potential side effects and identifying a group of patients prone to toxicity. MicroRNAs have been shown to have a predictive potential for radiotoxicity. The goal of the study was to test if levels of miRNA in peripheral blood mononuclear cells of glioblastoma patients are associated with toxicity and to identify the peak time point for toxicity. MicroRNA-10b/21/34a levels were measured in 43 patients with and without toxicity, at baseline, at the 15th, and at the 30th fraction by Real-Time quantitative Polymerase Chain Reaction. MicroRNA-10b/21 levels increased with toxicity grade (p = 0.014; p = 0.013); miR-21/34a levels were significantly different between patients with and without toxicity at the 15th fraction (p = 0.030; p = 0.045), while miR-34a levels significantly changed during treatment (p < 0.001). All three miRNAs showed a significantly high positive correlation with one another. MiR-34a might be considered as a predictive factor for toxicity due to its changes during treatment, and differences between the groups with and without toxicity; miR-10b might be used to predict toxicity; miR-10b/21 might be used for predicting the grade of toxicity in GB patients.

Clinical profile, treatment and outcome of pediatric brain tumors in Serbia in a 10-year period: A national referral institution experience.

OBJECTIVE: This study aimed to evaluate the characteristics of children with primary brain tumors, the effectiveness of treatment modalities, and to detect factors related to the outcome. METHODS: A detailed analysis was performed on a series of 173 pediatric patients treated in a Serbian referral oncology institution between 2007 and 2016, based on their clinical, histological, treatment, and follow-up data. RESULTS: Mean survival time of all children was 94.5months. 2-, 5- and 10-year overall survival probabilities were 68.8%, 59.4%, and 52.8%, respectively. Patients with supratentorial tumors had longer survival than patients with infratentorial tumors and patients with tumors in both compartments (p = 0.011). Children with the unknown histopathology (brainstem glioma) and high-grade glioma had a shorter life than embryonal tumors, ependymoma, and low-grade glioma (p<0.001). Survival of the children who underwent gross total resection was longer than the children in whom lesser degrees of resection were achieved (p = 0.015). The extent of the disease is a very important parameter found to be associated with survival. Patients with no evidence of disease after surgery had a mean survival of 123 months, compared with 82 months in patients with local residual disease and 55 months in patients with disseminated disease (p<0.001). By the univariate analysis, factors predicting poor outcome in our series were the presentation of disease with hormonal abnormalities, tumor location, and the extent of the disease, while the factors predicting a better outcome were age at the time of diagnosis, presentation of the disease with neurological deficit, and type of resection. By the multivariate analysis, the extent of the disease remained as the only strong adverse risk factor for survival (HR 2.06; 95% CI = 1.38-3.07; p<0.001). CONCLUSIONS: With an organized and dedicated multidisciplinary team, the adequate outcomes can be achieved in a middle-income country setting. The presence of local residual disease after surgery and disseminated disease has a strong negative effect on survival.

Dural metastasis of prostate carcinoma misdiagnosed as a bilateral subdural hematoma: A case report.

Dural metastases originating from prostate cancer are exceedingly uncommon and may clinically imitate a subdural hematoma. Additionally, head computed tomography scan findings can be mistaken for meningioma or subdural hematoma. We present a 75-year-old male patient with dural metastasis as a first presenting sign of prostate cancer, misdiagnosed as a bilateral subdural hematoma on initial non-contrast brain CT scan. Also, a review of literature is presented. We found 12 cases of dural metastasis of prostate cancer mimicking subdural hematoma described in the literature, and unlike in our case, prostate cancer was already diagnosed.

Low-grade epilepsy-associated tumour management with or without presurgical evaluation: a multicentre, retrospective, observational study of postsurgical epilepsy outcome.

Low-grade epilepsy-associated neuroepithelial tumours (LEATs) encompass the broad spectrum of tumours associated with epilepsy. Since the postsurgical seizure outcome in LEATs is favourable, it is speculated that epileptological presurgical evaluation (EPE) might not be required for patients with LEATs. A multicentre study involving referring epilepsy and neurosurgery centres was performed, aimed at evaluating postsurgical epilepsy outcome in patients with LEATs, with and without EPE, including long-term video-EEG monitoring (vEEGM). In total, 149 surgically treated patients were enrolled (age: 31±14 years; age at surgery: 26.4±13.1 years; males; 55.7%) with histopathological confirmation of LEATs and follow-up of more than six months. All patients had undergone standard assessment: clinical, routine EEG and brain MRI. In addition to vEEGM, EPE included other additional investigations. Epileptologists did not assess patients treated in neurosurgical centres. The EPE was performed in 51% of patients. Histopathological diagnosis revealed ganglioglioma in 43.6%, DNET in 32.9%, pilocytic astrocytoma in 17.4%, and others in 6.1% of patients. The majority of patients were seizure-free (ILAE epilepsy surgery outcome Class 1; 71.1%). The median follow-up period was 36 months. Patients who were rendered seizure-free were younger (mean age: 24.2±12.2) than those who were not seizure-free (31.8±14.0) (p=0.001). No difference was identified between evaluated and non-evaluated patients with respect to seizure freedom (p=0.45). EPE patients had a longer epilepsy duration (median: 10 years) and a higher proportion of drug resistance (73.6%) compared to non-evaluated patients (median: two years; 26.4%) (p<0.001). Based on a significant difference in major clinical variables, that may well affect postoperative results, the similar postsurgical seizure outcome in groups with and without EPE observed in our study should be considered with caution, and conclusions as to whether there is value in formal presurgical evaluation in LEAT patients cannot be drawn. Our data strongly encourage the clear need for continued discussion around such patients at epilepsy management conferences.

Computational quantitative MR image features - a potential useful tool in differentiating glioblastoma from solitary brain metastasis.

PURPOSE: Glioblastomas (GBM) and metastases are the most frequent malignant brain tumors in the adult population. Their presentation on conventional MRI is quite similar, but treatment strategy and prognosis are substantially different. Even with advanced MR techniques, in some cases diagnostic uncertainty remains. The main objective of this study was to determine whether fractal, texture, or both MR image analyses could aid in differentiating glioblastoma from solitary brain metastasis. METHOD: In a retrospective study of 55 patients (30 glioblastomas and 25 solitary metastases) who underwent T2W/SWI/CET1 MRI, quantitative parameters of fractal and texture analysis were estimated, using box-counting and gray level co-occurrence matrix (GLCM) methods. RESULTS: All five GLCM parameters obtained from T2W images showed significant difference between glioblastomas and solitary metastases, as well as on CET1 images except correlation (SCOR), contrary to SWI images which showed different values of two parameters (angular second moment-SASM and contrast-SCON). Only three fractal features (binary box dimension-Dbin, normalized box dimension-Dnorm and lacunarity-λ) measured on T2W and Dnorm measured on CET1 images significantly differed GBMs from solitary metastases. The highest sensitivity and specificity were obtained from inverse difference moment (SIDM) on T2W and SIDM on CET1 images, respectively. Combination of several GLCM parameters yielded better results. The processing of T2W images provided the most significantly different parameters between the groups, followed by CET1 and SWI images. CONCLUSIONS: Computational-aided quantitative image analysis may potentially improve diagnostic accuracy. According to our results texture features are more significant than fractal-based features in differentiation glioblastoma from solitary metastasis.

The possible benefit from total tumour resection in primary diffuse large B-cell lymphoma of central nervous system - a one-decade single-centre experience.

BACKGROUND AND METHODS: The aim of the study was to evaluate retrospectively clinical course of 27 patients with primary central nervous system lymphoma (PCNSL) diagnosed and treated by different surgical approaches. Initial therapy-diagnostic approach included surgery with total tumour reduction (TTR) performed in 12 patients (44.4%), while partial reduction and biopsy were performed in 8 (29.7%) and 7 (25.9%) patients, respectively. All patients were treated with chemotherapy based on high-dose methotrexate (HD-MTX) with/without whole-brain radiotherapy (WBRT). RESULTS: The median overall survival (OS) and event-free survival were 37 and 31 months, respectively, with overall response rate of 74%. The patients who underwent an open surgery with TTR had significantly longer OS (median not reached), comparing with partial tumour reduction or biopsy only (Log-Rank χ(2) 6.08, p = 0.014) when median OS was 23 months. In patients with performance status according to Eastern Cooperative Oncology Group (ECOG PS) ≥ 3, OS was 23 months, contrary to ECOG PS 1-2 when median was not reached. The International Extranodal Lymphoma Study Group score (low, intermediate and high) also influenced OS between three risk groups (Log-Rank χ(2) 12.5, p = 0.002). CONCLUSION: The treatment of PCNSL still remains doubtful, however possible benefit from the TTR followed with HD-MTX with/without WBRT should be reconsidered.

The Influence of Adjuvant Radiotherapy in Atypical and Anaplastic Meningiomas: A Series of 88 Patients in a Single Institution.

OBJECTIVE: Atypical and anaplastic meningiomas (World Health Organization classification grade II and III) represent a small and heterogeneous subgroup of meningiomas that has a more aggressive biological nature and higher frequency of recurrence. The atypical form accounts for 4.7%-7.2%, whereas the anaplastic type accounts for 1%-2.8% of all meningiomas. The aim of this study is to evaluate the role of postoperative radiotherapy on overall survival and progression-free survival in patients operated for atypical and anaplastic meningiomas. METHODS: A retrospective analysis of the patients operated at the Clinic of Neurosurgery, Clinical Center of Serbia, Belgrade, between January 1, 1995 and December 31, 2006 was performed. In that period 88 lesions met the histologic criteria for atypical (75) and anaplastic (13) meningiomas. Postoperative radiotherapy was conducted in 63.6% of patients. RESULTS: At a median follow-up of 67.4 months the overall survival was 68 months and the 5-year survival was about 54.5%. The median survival was 76 months with surgery and adjuvant radiotherapy and 40 months with surgery alone (log rank = 7.4; P = 0.006). Recurrent disease occurred in 58 patients (65.9%). Median time between first surgery and tumor recurrence in patients undergoing radiotherapy was 51 months, whereas in the nonirradiated group it was 24 months (log rank = 17.7; P < 0.001). Multivariate analysis identified as recurrence-predicting factors anaplastic histotype (hazard ratio = 2.9; P = 0.003) and postoperative radiotherapy (hazard ratio = 4.5; P < 0.001). CONCLUSIONS: The addition of adjuvant radiotherapy to surgery for atypical and anaplastic meningiomas resulted in a clinically meaningful and statistically significant survival benefit.