The diagnostic challenge of lack of choline level elevation on 1H-MR spectroscopy in grade II-III gliomas.

The accurate diagnosis of brain tumour is very important in modern neuro-oncology medicine. Magnetic resonance spectroscopy (MRS) is supposed to be a promising tool for detecting cancerous lesions. However, the interpretation of MRS data is complicated by the fact that not all cancerous lesions exhibit elevated choline (Cho) levels. The main goal of our study was to investigate the lack of Cho lesion /Cho ref elevation in the population of grade II-III gliomas. 89 cases of gliomas grade II and III were used for the retrospective analysis - glioma (astrocytoma or oligodendroglioma) grade II (74 out of 89 cases [83%]) and III (15 out of 89 cases [17%]) underwent conventional MRI extended by MRS before treatment. Histopathological diagnosis was obtained either by biopsy or surgical resection. Gliomas were classified to the group of no-choline elevation when the ratio of choline measured within the tumour (Cho lesion ) to choline from NABT (Cho ref ) were equal to or lower than 1. Significant differences were observed between ratios of Cho lesion /Cr lesion calculated for no-choline elevation and glial tumour groups as well as in the NAA lesion /Cr lesion ratio between the no-choline elevation group and glial tumour group. With consistent data concerning choline level elevation and slightly lower NAA value, the Cho lesion /NAA lesion ratio is significantly higher in the WHO II glial tumour group compared to the no-choline elevation cases ( p < 0.000). In the current study the results demonstrated possibility of lack of choline elevation in patients with grade II-III gliomas, so it is important to remember that the lack of elevated choline levels does not exclude neoplastic lesion.

Determinants of the level of circulating-tumor HPV16 DNA in patients with HPV-associated oropharyngeal cancer at the time of diagnosis.

Circulating tumor HPV DNA (ctHPV16) assessed in liquid biopsy may be used as a marker of cancer in patients with HPV-associated oropharyngeal cancer (HPV + OPC). Factors influencing the initial ctHPV16 quantity are not well recognized. In this study we aimed to establish what factors are related to the level of ctHPV16 at the time of diagnosis. 51 patients (37 men and 14 women, median age of 57 years old) with HPV + OPC prior to definitive treatment were included. ctHPV16 was measured by qPCR. Tumor and nodal staging were assessed according to AJCC8. Blood derived factors included squamous cell carcinoma antigen (SCC-Ag), serum soluble fragment of cytokeratin 19 (CYFRA 21-1), C-reactive protein (CRP), albumin level (Alb), neutrophils (Neut), thrombocytes (Plt) and lymphocyte (Lym) count, Neut/Lym ratio were assessed. The volumes of the primary tumor (TV) and involved lymph nodes (NV) were calculated using MRI, CT or PET-CT scans. Data were analysed using parametric and nonparametric methods. Variables for multivariable linear regression analysis were chosen based on the results from univariable analysis (correlation, univariable regression and difference). There were 9 (18%), 10 (19%) and 32 (63%) patients who had TV and NV assessed in MRI, CT or PET respectively. Primary tumor neither as T-stage nor TV was related to ctHPV16 level. Significant differences in the ctHPV16 between patients with high vs low pain (P = 0.038), NV (P = 0.023), TV + NV (P = 0.018), CYFRA 21-1 (P = 0.002), CRP (P = 0.019), and N1 vs N3 (P = 0.044) were observed. ctHPV16 was significantly associated with CYFRA 21-1 (P = 0.017), N stage (P = 0.005), NV (P = 0.009), TV + NV (P = 0.002), CRP (P = 0.019), and pain (P = 0.038). In univariable linear regression analysis the same variables predicted ctHPV16 level. In multivariable analyses, CYFRA 21-1 and CRP (both as categorical variables) were predictors of ctHPV16 level even above NV. ctHPV16 at presentation is driven by tumor volume measured mostly by N. CYFRA 21-1 and CRP are additional factors related to ctHPV16 prior to the treatment.

Assessment of sodium (23Na) brain MRI at 3T - preliminary results.

Purpose: The purpose of this work was to establish a database of tissue sodium concentration (TSC) in the normal brain of healthy volunteers. Tissue sodium concentration can be used as a sensitive marker of tissue viability in stroke or radiation therapy monitoring. Material and methods: Thirty-seven volunteers were scanned with a 23Na protocol in the span of one year; within this group, 29 studies were of acceptable quality. The study was approved by the Local Bioethics Committee. Data were acquired during a single magnetic resonance (MR) scanner session. The single scanner session consisted of 23Na 3D radial gradient echo (GRE) acquisition, MPRage, SPACE-FLAIR, and Resolve-DTI. MPRage images were segmented to obtain masks of the grey matter (GM), white matter (WM), and cerebrospinal fluid (CSF), which were registered to the sodium image space for image analysis. Images were transformed into TSC maps - a signal calibration curve obtained from the reference phantom of known sodium concentration and known relaxation time. Results: The collected data were analysed in 2 different ways: volunteers were divided by sex and by age. No significant differences in TSC were found between sexes. In all comparisons there was a significant difference in TSC between younger and older volunteers. In healthy volunteers mean TSC were as follows: GM 33.21 ± 4.76 mmol/l, WM 28.41 ± 4.03 mmol/l and for CSF 41.3 ± 6.69 mmol/l. Conclusions: This preliminary work is a base for further work with sodium imaging in brain lesions. The entirety of the col-lected data will be useful in the future as a baseline brain TSC for comparison to values obtained from pathologies.

Results of Primary Treatment and Salvage Treatment in the Management of Patients with Non-Squamous Cell Malignant Tumors of the Sinonasal Region: Single Institution Experience.

Non-squamous cell carcinoma-related malignant sinonasal tract tumors (non-SCC MSTT) are rare and diverse malignancies. In this study, we report our experience in the management of this group of patients. The treatment outcome has been presented, involving both primary treatment and salvage approaches. Data from 61 patients treated radically due to non-SCC MSTT between 2000 and 2016 at the National Cancer Research Institute, Gliwice branch, were analyzed. The group consisted of the following pathological subtypes of MSTT: adenoid cystic carcinoma (ACC), undifferentiated sinonasal carcinoma (USC), sarcoma, olfactory neuroblastoma (ONB), adenocarcinoma, small cell neuroendocrine carcinoma (SNC), mucoepidermic carcinoma (MEC), and acinic cell carcinoma, which were found in nineteen (31%), seventeen (28%), seven (11.5%), seven (11.5%), five (8%), three (5%), two (3%) and one (2%) of patients, respectively. There were 28 (46%) males and 33 (54%) females at the median age of 51 years. Maxilla was the primary tumor localization followed by the nasal cavity and ethmoid sinus in thirty-one (51%), twenty (32.5%), and seven (11.5%) patients, respectively. In 46 (74%) patients, an advanced tumor stage (T3 or T4) was diagnosed. Primary nodal involvement (N) was found in three (5%) cases, and all patients underwent radical treatment. The combined treatment consisted of surgery and radiotherapy (RT) and was given to 52 (85%) patients. The probabilities of overall survival (OS), locoregional control (LRC), metastases-free survival (MFS), and disease-free survival (DFS) were assessed in pathological subtypes and grouped together, along with the ratio and effectiveness of salvage. Locoregional treatment failure was seen in 21 (34%) patients. Salvage treatment was performed in fifteen (71%) patients and was effective in nine (60%) cases. There was a significant difference in OS between patients who underwent salvage and those who did not (median: 40 months vs. 7 months, p = 0.01). In the group of patients who underwent salvage, OS was significantly longer when the procedure was effective (median: 80.5 months) than if it failed (median: 20.5 months), p < 0.0001. OS in patients after effective salvage was the same as in patients who were primary cured (median: 80.5 months vs. 88 months, p = 0.8). Distant metastases developed in ten (16%) patients. Five and ten year LRC, MFS, DFS, and OS were 69%, 83%, 60%, 70%, and 58%, 83%, 47%, 49%, respectively. The best treatment results were observed for patients with adenocarcinoma and sarcoma, while USC gave the poorest results in our set of patients. In this study, we indicate that salvage is possible in most patients with non-SCC MSTT with locoregional failure and that it may significantly prolong their overall survival.

The use of MR perfusion parameters in differentiation between glioblastoma recurrence and radiation necrosis.

INTRODUCTION: This study focuses on the challenge of distinguishing between tumour recurrence and radiation necrosis in glioma treatment using magnetic resonance imaging (MRI). Currently, accurate differentiation is possible only through surgical biopsy, which is invasive and may cause additional damage. The study explores non-invasive methods using dynamic susceptibility contrast (DSC) MR perfusion with parameters like relative peak height (rPH) and relative percentage of signal-intensity recovery (rPSR). MATERIAL AND METHODS: Among retrospectively evaluated patients (multicentre study) with an initial diagnosis of the primary and secondary brain tumour, 47 met the inclusion criteria and were divided into two groups, the recurrent glioblastoma (GBM) WHO IV group and the radiation necrosis group, based on MRI of the brain. All patients enrolled into the recurrent GBM group had a second surgical intervention. RESULTS: Mean, minimum and maximum rPH values were significantly higher in the recurrent GBM group than in the radiation necrosis group ( p < 0.001), while rPSR values were lower in the recurrent GBM group than in the radiation necrosis group ( p = 0.011 and p = 0.012). DISCUSSION: This study investigates the use of MR perfusion curve characteristics to differentiate between radiation necrosis and glioblastoma recurrence in post-treatment brain tumours. MR perfusion shows promising potential for distinguishing between the two conditions, but it also has certain limitations. Despite challenges in finding a sufficient cohort size, the study demonstrates significant differences in MR perfusion parameters between radiation necrosis and GBM recurrence. CONCLUSIONS: The results demonstrate the potential usefulness of these DSC perfusion parameters in discriminating between glioblastoma recurrence and radiation necrosis.

Evaluation of 3T proton MR spectroscopy in the spinal cord - preliminary results.

Purpose: 1H-magnetic resonance spectroscopy (1H-MRS) is a non-invasive technique that provides information on tissue metabolism and biochemistry. Because of technical difficulties, this method is rarely used in spinal cord examination. The main goal of this study was to develop a routine protocol for MRS of intramedullary lesions. Material and methods: A 1H-MRS protocol was set on a group of healthy volunteers. Forty-eight spectra were acquired in total. Thirty of them were acquired in cervical spinal cord, and the remaining 18 spectra were acquired in the thoracic spinal cord. Results: In 1H-MRS of the spinal cord one of the most important problems is small voxel size. Mean voxel size in this study was 7 × 9 × 29 mm, which is much smaller than in brain examinations. Finally, almost 60% of spectra were of acceptable quality in volunteer examinations, which enabled the subsequent examinations. Conclusions: Challenges of spinal cord spectroscopy were discussed, and the ability of providing additional diagnostic information was proven.

In-bore MR prostate biopsy - initial experience.

INTRODUCTION: The introduction of multiparametric MRI (mpMRI) has been a breakthrough in the diagnosis of noninvasive clinically significant prostate cancer. Currently, MR-guided prostate biopsy (in-bore biopsy) is the only biopsy method that uses real-time MRI in patients with suspected prostate cancer. The aim of the study was a retrospective analysis of the correlation between MRI results and histological findings of prostate samples suspected of malignancy, which were taken during MRI-guided biopsy. MATERIAL AND METHODS: Thirty-nine patients with 57 lesion biopsies were enrolled in the study. Patients were aged 48-84 years (mean age 67.2 ± 9.4 years). RESULTS: Cancer was histologically confirmed in 24 lesions, including primary cancer in 14 lesions and local recurrence in 10 lesions. Cancer was not detected in the remaining lesions (n = 33). Malignancy was confirmed in 90% of lesions previously reported as PI-RADS 5. Only one Prostate Imaging and Reporting and Data System (PI-RADS 5) lesion was histologically negative (prostatitis). Cancer was detected in 50% of lesions defined as PI-RADS 4. Cancer cells were not found in any of 23 lesions defined as PI-RADS 3 (53.5%). Most of the lesions assessed as PI-RADS 3 were located in the transitional zone (n = 19). Only four PI-RADS 3 lesions were found in the peripheral zone. Large lesions or lesions feasible for cognitive TRUS biopsy were not referred for MRI biopsy, which resulted in a higher proportion of lesions assessed as PI-RADS 3. Fourteen lesions suspected of local recurrence were assessed in our study. Cancer was found in approximately 72% of the lesions. CONCLUSIONS: Performing prostate biopsy under the guidance of real-time MRI allows precise collection of material for histological examination (even from a very small lesion). As a result, both primary cancer and local recurrence after previous radiotherapy of prostate cancer can be confirmed.

Diagnosis and treatment of thyroid cancer in adult patients - Recommendations of Polish Scientific Societies and the National Oncological Strategy. 2022 Update [Diagnostyka i leczenie raka tarczycy u chorych doroslych - Rekomendacje Polskich Towarzystw Naukowych oraz Narodowej Strategii Onkologicznej. Aktualizacja na rok 2022].

The guidelines Thyroid Cancer 2022 are prepared based on previous Polish recommendations updated in 2018. They consider international guidelines - American Thyroid Association (ATA) 2015 and National Comprehensive Cancer Network (NCCN); however, they are adapted according to the ADAPTE process. The strength of the recommendations and the quality of the scientific evidence are assessed according to the GRADE system and the ATA 2015 and NCCN recommendations. The core of the changes made in the Polish recommendations is the inclusion of international guidelines and the results of those scientific studies that have already proven themselves prospectively. These extensions allow de-escalation of the therapeutic management in low-risk thyroid carcinoma, i.e., enabling active surveillance in papillary microcarcinoma to be chosen alternatively to minimally invasive techniques after agreeing on such management with the patient. Further extensions allow the use of thyroid lobectomy with the isthmus (hemithyroidectomy) in low-risk cancer up to 2 cm in diameter, modification of the indications for postoperative radioiodine treatment toward personalized approach, and clarification of the criteria used during postoperative L-thyroxine treatment. At the same time, the criteria for the preoperative differential diagnosis of nodular goiter in terms of ultrasonography and fine-needle aspiration biopsy have been clarified, and the rules for the histopathological examination of postoperative thyroid material have been updated. New, updated rules for monitoring patients after treatment are also presented. The updated recommendations focus on ensuring the best possible quality of life after thyroid cancer treatment while maintaining the good efficacy of this treatment.

Surgical treatment of brainstem cavernomas using diffusion tensor imaging and diffusion tensor tractography.

INTRODUCTION: The aims of this study were to assess the prognosis of patients after a single haemorrhage from the cavernoma, and also in the case of rehaemorrhage, and to determine the indications for surgical treatment of brainstem cavernomas. MATERIAL AND METHODS: The study included a group of 35 patients with brainstem cavernomas, 23 women and 12 men aged 27 to 57 years (mean age 38.4). Up to 2005, MRI perfusion-weighted imaging/diffusion-weighted imaging had been carried out in 13 surgically treated patients. From 2005 onwards, the other 22 patients also underwent MRI diffusion tensor imaging and diffusion tensor tractography (DTI/DTT). DTI/DTT assessed the course of long fibre tracts. The course of the corticospinal tract, medial lemniscus and transverse pontine tracts was entered into the neuronavigation system. The surgical approach and the safe entry zone were determined based on the DTI/DTT. RESULTS: Our study showed that rehaemorrhage from a cavernoma depends on its size and volume. However, it is not related to its location. Based on the modified Rankin scale, the results of treatment of our patients after the first haemorrhage were better compared to the assessment after another haemorrhage. Complete resection was performed in 32 cases (91%) and partial resection in the remaining three (9%). Two patients underwent another surgery after several years due to partial resection. One patient presented with another haemorrhage after three years. New deficits developed postoperatively. Already existing deficits were exacerbated, but gradually resolved. Symptoms of cerebellar dysfunction and cranial nerve injury (including respiratory disorders) were the most difficult to resolve. CONCLUSIONS: Patients with brainstem cavernomas should undergo surgical treatment after their first haemorrhage, especially in the case of a large cavernoma. DTI/DTT should be used to determine the trajectory to the cavernoma, particularly to the deep cavernoma, and to determine the safe entry zone. Total resection of the cavernoma should be performed even where this means that reoperation is required.

Two professions against two killer diseases: the rationale, organization, and initial experience of a cardio-oncology service.

BACKGROUND: Cardiovascular diseases are the most common factor affecting prognosis in cancer survivors. Cardio­oncology (CO) services have been developed to solve this issue. The outcomes regarding patient demographics and clinical findings are limited and the available data include CO services evaluating patients undergoing only chemotherapy as opposed to those also undergoing radiation therapy. AIMS: We aimed to show initial experiences of the CO service implemented in a tertiary oncology center. METHODS: The CO service was designed to include 2 major domains, general CO and electrotherapy consultations. This observational study included patients referred to the CO service with the following data: baseline demographics, cancer type, reasons for referral, cardiac evaluation, and initial clinical outcomes. RESULTS: All patients with cancer referred to our CO service between March 2016 and December 2019 were included in the study. A total of 2762 patients (77% women) at the mean (SD) age of 62 (12) years were referred (63% on an out­patient basis) for general consultations. The most frequent diagnosis was breast cancer (66%). A total of 18% of patients were referred to the CO service due to cardiovascular complications related to cancer treatment. The CO-cardiac implantable electronic device (CIED) team evaluated 652 patients (515 patients with CIEDs who were qualified for radiotherapy, 48 patients with CIEDs who were assessed with magnetic resonance imaging, and 89 patients with CIEDs who underwent cancer surgery). In the total of 5872 radiotherapy sessions, there were 2 harmful interactions; no other complications during magnetic resonance imaging and surgery were recorded. CONCLUSIONS: The CO­service established within the cancer center seems to be safe and feasible.

Pulmonary Complications After Allogeneic Hematopoietic Stem Cell Transplantation for Multiple Myeloma: A Case Report.

We present a case of a young patient with life-threatening pulmonary complications after allogeneic hematopoietic stem cell transplantation (HSCT). The 25-year-old woman, after HSCT for multiple myeloma, developed severe chronic graft-vs-host disease (GvHD), including bronchiolitis obliterans syndrome. During the treatment of chronic GvHD, 18 months after HSCT, she experienced sudden massive pulmonary hemorrhage with cardiac arrest. The computed tomography imaging revealed lesions suggestive of fungal etiology, with cavity adjacent to the pulmonary vessels. Disqualified from invasive treatment due to poor pulmonary performance, she was treated conservatively with broad-spectrum antibiotics and antifungals. The microbiological workup consistently revealed only Pseudomonas aeruginosa colonization. Her condition steadily improved on treatment. Over 18 months after the incident, she did not experience recurrent bleeding nor serious infection, her primary disease remains in remission, and GvHD symptoms are controlled. Allogeneic HSCT offers possibility of sustained immune-mediated disease control and sometimes even cure, but despite reduced transplant related mortality, GvHD and infections may be detrimental for transplant recipients. Our report illustrates atypical manifestation of pulmonary lesions and highlights the importance of infection control during GvHD treatment.

Whole Brain and Cranial Size Adjustments in Volumetric Brain Analyses of Sex- and Age-Related Trends.

Our goal was to determine the influence of sex, age and the head/brain size on the compartmental brain volumes in the radiologically verified healthy population (96 subjects; 54 women and 42 men) from the Upper Silesia region in Poland. The MRI examinations were done using 3T Philips Achieva with the same T1-weighted and T2-weighted protocols. The image segmentation procedures were performed with SPM (Statistical Parameter Mapping) and FSL-FIRST software. The volumes of 14 subcortical structures for the left and right hemispheres and 4 overall volumes were calculated. The General Linear Models (GLM) analysis was used with and without the Total Brain Volume (TBV) and Intracranial Volume (ICV) parameters as the covariates to study the regional vs. global brain atrophy. After the ICV/TBV adjustments, the majority of sex differences in the specific volumes of interest (VOIs) revealed to be linked to the difference in the head/brain size parameters. The analysis also confirmed the significant effect of the aging process on the brain loss. After the TBV adjustment, the age- and sex-related volumetric trends for the gray and white matter volumes were observed: the negative age dependence of the gray matter volume is more pronounced in the males, while in case of the white matter the positive age-related trend in the female group is weaker. The local losses of the left caudate nucleus and the right thalamus are more advanced than the global brain atrophy. Different head-size correction strategies are not interchangeable and may yield various volumetric results, but when used together, facilitate studies on the regional dependencies inherent to a healthy, but aging, brain.

Circulating HPV16 DNA may complement imaging assessment of early treatment efficacy in patients with HPV-positive oropharyngeal cancer.

BACKGROUND: Early detection of treatment failure may improve clinical outcome and overall survival in patients with head and neck cancer after first-line treatment. Circulating cell-free HPV16 DNA (cfHPV16 DNA) was evaluated as a possible complementary marker to radiological assessment of early response in patients with HPV-related oropharyngeal cancer (OPC) after radiotherapy alone or combined with chemotherapy. METHODS: The study included 66 patients with HPV-related OPC receiving radical radiotherapy alone or in combination with chemotherapy. cfHPV16 DNA was assessed in the blood of all patients before treatment using TaqMan-based qPCR. Subsequent analysis of cfHPV16 DNA was performed 12 weeks after treatment completion, along with radiological assessment of early treatment results. RESULTS: Complete (CRR) and incomplete radiological response (IRR) was found in 43 (65%) and 23 (35%) patients respectively. cfHPV16 DNA was present in 5 (28%) patients with IRR, while only in 1 (4%) with CRR. Three of five patients with IRR that were positive for cfHPV16 DNA exhibited histopathologically confirmed local or regional treatment failure, and other two developed distant metastases. None of the patients with negative cfHPV16 DNA presented disease failure. CONCLUSION: The post-treatment assessment of cfHPV16 DNA in patients with HPV-related OPC may be used as a complementary biomarker to conventional imaging-based examinations for early identification of treatment failure.

Fully-automated deep learning-powered system for DCE-MRI analysis of brain tumors.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) plays an important role in diagnosis and grading of brain tumors. Although manual DCE biomarker extraction algorithms boost the diagnostic yield of DCE-MRI by providing quantitative information on tumor prognosis and prediction, they are time-consuming and prone to human errors. In this paper, we propose a fully-automated, end-to-end system for DCE-MRI analysis of brain tumors. Our deep learning-powered technique does not require any user interaction, it yields reproducible results, and it is rigorously validated against benchmark and clinical data. Also, we introduce a cubic model of the vascular input function used for pharmacokinetic modeling which significantly decreases the fitting error when compared with the state of the art, alongside a real-time algorithm for determination of the vascular input region. An extensive experimental study, backed up with statistical tests, showed that our system delivers state-of-the-art results while requiring less than 3 min to process an entire input DCE-MRI study using a single GPU.

Association of breast cancer grade with response to neoadjuvant chemotherapy assessed postoperatively.

Currently, breast cancer chemotherapy response can be predicted based on various parameters, with common reporting of tumour grade and Ki67 proliferation index. We analysed their association with pathological complete response (pCR) in a multivariate approach. The study was carried out in a group of 353 patients, treated by preoperative chemotherapy and prospectively observed. In selected patients, parallel to routing core needle biopsy assessment, gene expression profile of tumour was analysed by oligonucleotide microarrays. Tumour parameters associated with pCR in univariate analysis were: tumour grade, nuclear grade, mitotic index, Ki67, oestrogen and progesterone receptor (all p < 0.0001), and triple-negative status (p = 0.0032). The highest increase of pCR chance was observed in patients with high-grade tumours and with Ki67 ≥ 20%. In multivariate analysis, only tumour grade and oestrogen receptor status were predictive for pCR independently of other variables, with high grade increasing the odds of pCR 2.42 fold, and high ER decreasing the chance of pCR 0.41 fold. Tumour grading reflects important biological features of breast cancer and is not inferior to proliferation markers, including Ki67. It should be taken into account in decision-making for preoperative chemotherapy in parallel to breast cancer biologic subtypes, because grade 3 tumours exhibit a higher proportion of pCR.

Segmenting brain tumors from FLAIR MRI using fully convolutional neural networks.

BACKGROUND AND OBJECTIVE: Magnetic resonance imaging (MRI) is an indispensable tool in diagnosing brain-tumor patients. Automated tumor segmentation is being widely researched to accelerate the MRI analysis and allow clinicians to precisely plan treatment-accurate delineation of brain tumors is a critical step in assessing their volume, shape, boundaries, and other characteristics. However, it is still a very challenging task due to inherent MR data characteristics and high variability, e.g., in tumor sizes or shapes. We present a new deep learning approach for accurate brain tumor segmentation which can be trained from small and heterogeneous datasets annotated by a human reader (providing high-quality ground-truth segmentation is very costly in practice). METHODS: In this paper, we present a new deep learning technique for segmenting brain tumors from fluid attenuation inversion recovery MRI. Our technique exploits fully convolutional neural networks, and it is equipped with a battery of augmentation techniques that make the algorithm robust against low data quality, and heterogeneity of small training sets. We train our models using only positive (tumorous) examples, due to the limited amount of available data. RESULTS: Our algorithm was tested on a set of stage II-IV brain-tumor patients (image data collected using MAGNETOM Prisma 3T, Siemens). Rigorous experiments, backed up with statistical tests, revealed that our approach outperforms the state-of-the-art approach (utilizing hand-crafted features) in terms of segmentation accuracy, offers very fast training and instant segmentation (analysis of an image takes less than a second). Building our deep model is 1.3 times faster compared with extracting features for extremely randomized trees, and this training time can be controlled. Finally, we showed that too aggressive data augmentation may lead to deteriorated performance of the model, especially in the fixed-budget training (with maximum numbers of training epochs). CONCLUSIONS: Our method yields the better performance when compared with the state of the art method which utilizes hand-crafted features. In addition, our deep network can be effectively applied to difficult (small, imbalanced, and heterogeneous) datasets, offers controllable training time, and infers in real-time.

Surgical treatment and prognosis of adult patients with brainstem gliomas.

The paper presents 47 adult patients who were surgically treated due to brainstem gliomas. Thirteen patients presented with contrast-enhancing Grades III and IV gliomas, according to the WHO classification, 13 patients with contrast-enhancing tumours originating from the glial cells (Grade I; WHO classification), 9 patients with diffuse gliomas, 5 patients with tectal brainstem gliomas and 7 patients with exophytic brainstem gliomas. During the surgical procedure, neuronavigation and the diffusion tensor tractography (DTI) of the corticospinal tract were used with the examination of motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs) with direct stimulation of the fundus of the fourth brain ventricle in order to define the localization of the nuclei of nerves VII, IX, X and XII. Cerebellar dysfunction, damage to cranial nerves and dysphagia were the most frequent postoperative sequelae which were also the most difficult to resolve. The Karnofsky score established preoperatively and the extent of tumour resection were the factors affecting the prognosis. The mean time of progression-free survival (14 months) and the mean survival time after surgery (20 months) were the shortest for malignant brainstem gliomas. In the group with tectal brainstem gliomas, no cases of progression were found and none of the patients died during the follow-up. Some patients were professionally active. Partial resection of diffuse brainstem gliomas did not prolong the mean survival above 5 years. However, some patients survived over 5 years in good condition.

Surgical treatment of adult patients with thalamic tumors with the aid of tractography, fMRI, transcranial electrical stimulation and direct electrical stimulation of the subcortical white matter.

The aim of investigation was to assess treatment outcomes in adult patients with thalamic tumors, operated on with the aid of tractography (DTI) and monitoring of motor evoked potentials (MEPs) generated due to transcranial electrical stimulation (TES) and direct electrical stimulation (DES) of the subcortical white matter. 38 subsequent patients with thalamic tumors were operated on using tractography (DTI)-integrated neuronavigation, transcranial electrical stimulation (TES) and direct electrical stimulation (DES). The volumetric method was used to calculate pre- and postoperative tumor volume. Total tumor resection (100%) was performed in 18 (47%) patients, subtotal in 9 (24%) (mean extent of resection -89.4%) and partial in 11 (29%) patients (mean extent of resection -77.18%). The mean extent of resection for all surgical patients was 86.5%. Two (5.2%) patients died postoperatively. Preoperative hemiparesis was present in 18 (47%) patients. Postoperative hemiparesis was observed in 11 (29%) patients of whom only in 5 (13%) new paresis was noted due to surgical intervention. In patients with hemiparesis significantly more frequently larger tumor volume was detected preoperatively. Low mean normal fractional anisotropy (nFA) values in the internal capsule were observed statistically significantly more frequently in patients with preoperative hemiparesis as compared to the internal capsule of the unaffected hemisphere. Transcranial electrical stimulation helps to predict postoperative paresis of extremities. Direct electrical stimulation is an effective tool for intraoperative localization of the internal capsule thus helping to avoid postoperative deficit. In patients with tumor grade I and II the median time to tumor progression was 36 months. In the case of patients with grades III and IV it was 14 months. The median survival time in patients with grades I and II it was 60 months. In patients with grades III and IV it was 18 months. Basing on our results, patients with glioma grade I/II according to WHO classification are the best candidates for surgical treatment of thalamic tumors. In this group of the patients more often resection is radical, median time to progression and survival time are longer than in patients with gliomas grade III and IV. Within a 7-year follow-up none of the patients with GI/GII grade glioma died.

Application of Intravoxel Incoherent Motion (IVIM) Model for Differentiation Between Metastatic and Non-Metastatic Head and Neck Lymph Nodes.

BACKGROUND: Application of intravoxel incoherent motion (IVIM) model parameters, including: true diffusion (D), pseudodiffusion (D*), and perfusion fraction (Fp), for differentiation between metastatic and non-metastatic head and neck lymph nodes. MATERIAL/METHODS: Diffusion-weighted images/apparent diffusion coefficient (DWI/ADC) images of 86 lymph nodes from 31 cancer patients were analyzed. DWI images were obtained with a 1.5T MRI scanner (Magnetom Avanto); b=0,50, 150, 300, 500, 750, 1000, 1200 s/mm2. RESULTS: In the study group, there were 32 (37%) and 54 (67%) metastatic and non-metastatic lymph nodes, respectively. The mean values of D, D*, and Fp did not differ significantly between metastatic and non-metastatic lymph nodes. CONCLUSIONS: IVIM parameters are not useful for differentiation between metastatic and non-metastatic head and neck lymph nodes.

Early Detection of Malignant Transformation in Resected WHO II Low-Grade Glioma Using Diffusion Tensor-Derived Quantitative Measures.

OBJECTIVE: Here, we retrospectively investigate the value of voxel-wisely plotted diffusion tensor-derived (DTI) axial, radial and mean diffusivity for the early detection of malignant transformation (MT) in WHO II glioma compared to contrast-enhanced images. MATERIALS AND METHODS: Forty-seven patients underwent brain magnetic resonance imaging follow-up between 2006-2014 after gross-tumor resection of intra-axial WHO II glioma. Axial/Mean/Radial diffusivity maps (AD/MD/RD) were generated from DTI data. ADmin/MDmin/RDmin values were quantified within tumor regions-of-interest generated by two independent readers including tumor contrast-to-noise (CNR). Sensitivity/specificity and area-under-the-curve (AUC) were calculated using receiver-operating-characteristic analysis. Inter-reader agreement was assessed (Cohen's kappa). RESULTS: Eighteen patients demonstrated malignant transformation (MT) confirmed in 8/18 by histopathology and in 10/18 through imaging follow-up. Twelve of 18 patients (66.6%) with MT showed diffusion restriction timely coincidental with contrast-enhancement (CE). In the remaining six patients (33.3%), the diffusion restriction preceded the CE. The mean gain in detection time using DTI was (0.8±0.5 years, p = 0.028). Compared to MDmin and RDmin, ROC-analysis showed best diagnostic value for ADmin (sensitivity/specificity 94.94%/89.7%, AUC 0.96; p<0.0001) to detect MT. CNR was highest for AD (1.83±0.14), compared to MD (1.31±0.19; p<0.003) and RD (0.90±0.23; p<0.0001). Cohen's Kappa was 0.77 for ADmin, 0.71 for MDmin and 0.65 for RDmin (p<0.0001, respectively). CONCLUSION: MT is detectable at the same time point or earlier compared to T1w-CE by diffusion restriction in diffusion-tensor-derived maps. AD demonstrated highest sensitivity/specificity/tumor-contrast compared to radial or mean diffusivity (= apparent diffusion coefficient) to detect MT.