Systematic review of the immunological landscape of Wilms tumors.

Results of immunotherapy in childhood solid cancer have been so far, with the exception of neuroblastoma, quite disappointing. Lack of knowledge of the immune contexture of these tumors may have contributed to the failure of immunotherapies so far. Here, we systematically reviewed the literature regarding the immunology of Wilms tumor (WT), one of the most frequent pediatric solid tumors of the abdomen. In Wilms tumor patients the high cure rate of >90%, achieved by the combination of surgery and radio-chemotherapy, is at the expense of a high early and late toxicity. Moreover, treatment-resistant entities, such as diffuse anaplastic tumors or recurrent disease, still pose unsolved clinical problems. Successful immunotherapy could represent a novel and possibly less-toxic treatment option. Employing the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) method of literature search, we analyzed the current knowledge of the immunological landscape of Wilms tumors in terms of tumor microenvironment, prognostic implications of single biomarkers, and immunotherapy response.

Diagnostic accuracy of ultrasound-guided core needle biopsy versus incisional biopsy in soft tissue sarcoma: an institutional experience.

Core needle biopsy (CNB) is gaining in importance due to its advantages in the matter of patient morbidity, time and cost. Nevertheless, controversies still exist regarding the biopsy technique of choice for the accurate diagnosis of soft tissue sarcoma (STS). This retrospective cohort study compared the diagnostic performance between ultrasound-guided CNB and incisional biopsy (IB), both performed by orthopedic surgeons. The aims of the study were to answer the following questions: (1) Is ultrasound-guided CNB a highly reliable modality for diagnosing STSs? (2) Is CNB equally useful to IB for identifying histologic subtype? (3) Had patients who underwent CNB a reduced risk of complications? One-hundred and fifty-three patients who underwent resection of soft tissue sarcoma were classified into two groups according to biopsy technique prior to surgery; CNB group (n = 95) and IB group (n = 58). The final surgical specimens were in 40 patients liposarcoma (myxoid, pleomorphic and dedifferentiated), 39 undifferentiated pleomorphic sarcoma (UPS), 33 myxofibrosarcoma, 10 synovial sarcoma, 10 leiomyosarcoma and in the remaining 21 patients different soft tissue sarcoma entities. Sarcoma location of 71 patients was in the thigh, 19 in the lower leg, 22 in the upper arm and shoulder area; 10 in the knee and gluteal region, 9 in the thoracic region, the residual 12 in other body areas. Malignancy was correctly diagnosed in 87% (83 of 95) for the CNB group and 93% (54/58) for the IB group. Correct identification rate of histologic subtype was 80% (76 of 95) in the CNB group and 83% (48 of 58) in the IB group. There were no significant differences in the correct diagnosis rates of malignancy and subtype between the two techniques. No complications were seen in the CNB group, whereas 2 patients in whom IB was performed developed pulmonary embolism and 1 patient surgical site infection. Ultrasound-guided CNB is highly accurate and not inferior to IB in diagnosing the dignity of lesions and histologic subtype in patients with suspected STSs.

Tumor DNA methylation profiles correlate with response to anti-PD-1 immune checkpoint inhibitor monotherapy in sarcoma patients.

BACKGROUND: Some sarcomas respond to immune checkpoint inhibition, but predictive biomarkers are unknown. We analyzed tumor DNA methylation profiles in relation to immunological parameters and response to anti-programmed cell death 1 (anti-PD-1) immune checkpoint inhibitor (ICI) therapy in patients with sarcoma. PATIENTS AND METHODS: We retrospectively identified adult patients who had received anti-PD-1 ICI therapy for recurrent sarcoma in two independent centers. We performed (1) blinded radiological response evaluation according to immune response evaluation criteria in solid tumors (iRECIST) ; (2) tumor DNA methylation profiling of >850,000 probes using Infinium MethylationEPIC microarrays; (3) analysis of tumor-infiltrating immune cell subsets (CD3, CD8, CD45RO, FOXP3) and intratumoral expression of immune checkpoint molecules (PD-L1, PD-1, LAG-3) using immunohistochemistry; and (4) evaluation of blood-based systemic inflammation scores (neutrophil-to-lymphocyte ratio, leucocyte-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, platelet-to-lymphocyte ratio). Response to anti-PD-1 ICI therapy was bioinformatically and statistically correlated with DNA methylation profiles and immunological data. RESULTS: 35 patients (median age of 50 (23-81) years; 18 females, 17 males; 27 soft tissue sarcomas; 8 osteosarcomas) were included in this study. The objective response rate to anti-PD-1 ICI therapy was 22.9% with complete responses in 3 out of 35 and partial responses in 5 out of 35 patients. Adjustment of DNA methylation data for tumor-infiltrating immune cells resulted in identification of methylation differences between responders and non-responders to anti-PD-1 ICI. 2453 differentially methylated CpG sites (DMPs; 2043 with decreased and 410 with increased methylation) were identified. Clustering of sarcoma samples based on these DMPs revealed two main clusters: methylation cluster 1 (MC1) consisted of 73% responders and methylation cluster 2 (MC2) contained only non-responders to anti-PD-1 ICI. Median progression-free survival from anti-PD-1 therapy start of MC1 and MC2 patients was 16.5 and 1.9 months, respectively (p=0.001). Median overall survival of these patients was 34.4 and 8.0 months, respectively (p=0.029). The most prominent DNA methylation differences were found in pathways implicated in Rap1 signaling, focal adhesion, adherens junction Phosphoinositide 3-kinase (PI3K)-Akt signaling and extracellular matrix (ECM)-receptor interaction. CONCLUSIONS: Our data demonstrate that tumor DNA methylation profiles may serve as a predictive marker for response to anti-PD-1 ICI therapy in sarcoma.

Long-Term Outcome and Role of Biology within Risk-Adapted Treatment Strategies: The Austrian Neuroblastoma Trial A-NB94.

We evaluated long-term outcome and genomic profiles in the Austrian Neuroblastoma Trial A-NB94 which applied a risk-adapted strategy of treatment (RAST) using stage, age and MYCN amplification (MNA) status for stratification. RAST ranged from surgery only to intensity-adjusted chemotherapy, single or multiple courses of high-dose chemotherapy (HDT) followed by autologous stem cell rescue depending on response to induction chemotherapy, and irradiation to the primary tumor site. Segmental chromosomal alterations (SCAs) were investigated retrospectively using multi- and pan-genomic techniques. The A-NB94 trial enrolled 163 patients. Patients with localized disease had an excellent ten-year (10y) event free survival (EFS) and overall survival (OS) of 99 ± 1% and 93 ± 2% whilst it was 80 ± 13% and 90 ± 9% for infants with stage 4S and for infants with stage 4 non-MNA disease both 83 ± 15%. Stage 4 patients either >12 months or ≤12 months but with MNA had a 10y-EFS and OS of 45 ± 8% and 47 ± 8%, respectively. SCAs were present in increasing frequencies according to stage and age: in 29% of localized tumors but in 92% of stage 4 tumors (p < 0.001), and in 39% of patients ≤ 12 months but in 63% of patients > 12 months (p < 0.001). RAST successfully reduced chemotherapy exposure in low- and intermediate-risk patients with excellent long-term results while the outcome of high-risk disease met contemporary trials.

Clear cell sarcoma of the kidney in Austrian children: Long-term survival after relapse.

INTRODUCTION: Clear cell sarcoma of the kidney (CCSK) is a rare malignant childhood renal tumour. Recently, the central nervous system (CNS) was found to be the most frequent site of relapse associated with a poor outcome. Optimal treatment strategies are scarce. PATIENTS AND METHODS: Retrospective data analysis of all Austrian children with CCSK. They were enrolled in the Austrian-Hungarian Wilms Tumour Study (AHWTS) 1989, the SIOP93-01 or the SIOP2001 study between 1990 and 2019. Demographic, diagnostic, treatment-related variables and survival data were analysed. RESULTS: We identified 12 children with CCSK (M = 7, F = 5; median age 1.6 years). All had localised disease (stage I: 2; stage II: 2; stage III: 8) at diagnosis, and a first complete remission (CR1) was achieved in 12/12. Six patients are in an ongoing CR1 (median follow-up 10 years). Six other patients had a relapse (local 1; brain 5) a median time of 2.4 years from diagnosis. Two patients died of the disease 4 months and 2.8 years after first relapse. Four of five patients with CNS relapse are in CR2 with a median follow-up time of 9.3 years after relapse diagnosis. Relapse treatment included a combination of chemotherapy, radiation and surgery. Two children received high-dose chemotherapy followed by autologous stem cell rescue, and one child received intrathecal mafosphamide. Long-term side effects after treatment were impaired tubular renal function (n = 4), cardiomyopathy (n = 1) and growth disorders (n = 1). CONCLUSIONS: In this series, the brain was the most common site of relapse. Long-term survival after recurrence was achievable with intensive multimodal therapy.

Undifferentiated round cell sarcomas with CIC-DUX4 gene fusion: expanding the clinical spectrum.

Round cell sarcomas are a heterogeneous group of mesenchymal neoplasms with overlapping morphology and immunohistochemical profile. Ewing sarcoma is the most well-known tumour in this group characterised by EWSR1/FUS rearrangements with members of the ETS family of transcription factors. Undifferentiated round cell sarcomas lacking these rearrangements, known as 'Ewing-like' sarcomas, usually show atypical clinical presentation and focal CD99 positivity. This group of tumours can be subdivided into: capicua transcriptional repressor (CIC)-rearranged sarcomas, Bcl6 corepressor (BCOR)-rearranged sarcomas, sarcomas with EWSR1 fusion to non-ETS family members and unclassified round cell sarcomas. We describe seven new cases of CIC-DUX4 rearranged sarcomas with their clinicopathological features, two of which presented in unusual locations (skin and lymph node). Patient age ranged between 23 and 54 years, three of whom were female. In five cases, aggressive behaviour was observed with rapid disease progression and lethal outcome within 15 months. One patient achieved a complete response after chemotherapy. The last patient whose tumour was located purely in the dermis demonstrated no residual tumour in the re-resection specimen, was not given any further treatment and showed no sign of disease after 24 months. Immunohistochemically, tumour cells in all cases showed focal membranous CD99 positivity, while WT1 N-/C-terminus were positive in all 5/5 cases (nuclear and/or cytoplasmic). NGS analysis revealed a CIC-DUX4 fusion in all cases. This study expands the spectrum of anatomical locations of CIC-DUX4 rearranged sarcomas, highlighting the inclusion of this rare entity in the differential diagnosis of undifferentiated tumours in various anatomical locations outside of soft tissues.

An optimized, robust and reproducible protocol to generate well-differentiated primary nasal epithelial models from extremely premature infants.

Extremely premature infants are prone to severe respiratory infections, and the mechanisms underlying this exceptional susceptibility are largely unknown. Nasal epithelial cells (NEC) represent the first-line of defense and adult-derived ALI cell culture models show promising results in mimicking in vivo physiology. Therefore, the aim of this study was to develop a robust and reliable protocol for generating well-differentiated cell culture models from NECs of extremely premature infants. Nasal brushing was performed in 13 extremely premature infants at term corrected age and in 11 healthy adult controls to obtain NECs for differentiation at air-liquid interface (ALI). Differentiation was verified using imaging and functional analysis. Successful isolation and differentiation was achieved for 5 (38.5%) preterm and 5 (45.5%) adult samples. Preterm and adult ALI-cultures both showed well-differentiated morphology and ciliary function, however, preterm cultures required significantly longer cultivation times for acquiring full differentiation (44 ± 3.92 vs. 23 ± 1.83 days; p < 0.0001). Moreover, we observed that recent respiratory support may impair successful NECs isolation. Herewithin, we describe a safe, reliable and reproducible method to generate well-differentiated ALI-models from NECs of extremely premature infants. These models provide a valuable foundation for further studies regarding immunological and inflammatory responses and respiratory disorders in extremely premature infants.

Interleukin-6 serum levels predict surgical intervention in infants with necrotizing enterocolitis.

BACKGROUND: Symptoms at suspicion of necrotizing enterocolitis (NEC) are often nonspecific and several biomarkers have been evaluated for their discriminative power to both diagnose and predict the course from NEC suspicion to complicated disease requiring surgical intervention. Thus, we aimed to assess the utility of interleukin-6 (IL-6) to predict surgical intervention in infants suffering from NEC and, furthermore, to discriminate infants with starting NEC or late-onset sepsis (LOS). METHODS: IL-6 serum levels at disease onset were retrospectively analyzed in 24 infants suffering from NEC as well as 16 neonates with LOS. RESULTS: IL-6 serum levels at disease onset were significantly higher in infants suffering from NEC necessitating surgical intervention in the disease course compared to infants with medical NEC (5000 [785-5000] vs. 370 [78-4716] pg/ml, p = 0.0008) as well as gram-positive LOS (5000 [785-5000] vs. 84 [12-269] pg/ml, p = 0.0001). Infants suffering from gram-negative LOS exhibited elevated IL-6 serum levels at disease onset comparable to infants with surgical NEC (5000 [1919-5000] vs. 5000 [785-5000] pg/ml, p = 1.00). CONCLUSION: The proinflammatory cytokine IL-6 appears to be a promising marker to distinguish surgical NEC from medical NEC at the onset of disease but cannot discriminate between surgical NEC and gram-negative LOS. LEVEL OF EVIDENCE: II.

Outcome of two patients with bilateral nephroblastomatosis/Wilms tumour treated with an add-on 13-cis retinoic acid therapy - Case report.

Although the fate of nephrogenic rests varies, they are known to be precursors of Wilms tumour. Thus, nephrogenic rests require adequate treatment to prevent malignant transformation. We added 13-cis retinoic acid to the standard chemotherapy with vincristine and actinomycin-D in two patients with bilateral nephrogenic rests/nephroblastomatosis. Patient 1 also had a history of Wilms tumour. 46 (patient 1) and 81 (patient 2) months after end of treatment, both patients show stable conditions with no signs of relapse or progressive disease. Our observation supports further investigation of retinoic acid in patients with nephrogenic rests and nephroblastomatosis.

Heterogeneous MYCN amplification in neuroblastoma: a SIOP Europe Neuroblastoma Study.

BACKGROUND: In neuroblastoma (NB), the most powerful prognostic marker, the MYCN amplification (MNA), occasionally shows intratumoural heterogeneity (ITH), i.e. coexistence of MYCN-amplified and non-MYCN-amplified tumour cell clones, called heterogeneous MNA (hetMNA). Prognostication and therapy allocation are still unsolved issues. METHODS: The SIOPEN Biology group analysed 99 hetMNA NBs focussing on the prognostic significance of MYCN ITH. RESULTS: Patients <18 months (18 m) showed a better outcome in all stages as compared to older patients (5-year OS in localised stages: <18 m: 0.95 ± 0.04, >18 m: 0.67 ± 0.14, p = 0.011; metastatic: <18 m: 0.76 ± 0.15, >18 m: 0.28 ± 0.09, p = 0.084). The genomic 'background', but not MNA clone sizes, correlated significantly with relapse frequency and OS. No relapses occurred in cases of only numerical chromosomal aberrations. Infiltrated bone marrows and relapse tumour cells mostly displayed no MNA. However, one stage 4s tumour with segmental chromosomal aberrations showed a homogeneous MNA in the relapse. CONCLUSIONS: This study provides a rationale for the necessary distinction between heterogeneous and homogeneous MNA. HetMNA tumours have to be evaluated individually, taking age, stage and, most importantly, genomic background into account to avoid unnecessary upgrading of risk/overtreatment, especially in infants, as well as in order to identify tumours prone to developing homogeneous MNA.

Monitoring of plexiform neurofibroma in children and adolescents with neurofibromatosis type 1 by [18 F]FDG-PET imaging. Is it of value in asymptomatic patients?

PURPOSE: About 10% of patients with neurofibromatosis type 1 (NF-1) develop malignant peripheral nerve sheath tumours (MPNST) mostly arising in plexiform neurofibroma (PN); 15% of MPNST arise in children and adolescents. 2-[18 F]fluoro-2-deoxy-d-glucose ([18 F]FDG)-PET (where PET is positron emission tomography) is a sensitive method in differentiating PN and MPNST in symptomatic patients with NF-1. This study assesses the value of [18 F]FDG-PET imaging in detecting malignant transformation in symptomatic and asymptomatic children with PN. METHODS: Forty-one patients with NF-1 and extensive PN underwent prospective [18 F]FDG imaging from 2003 to 2014. Thirty-two of the patients were asymptomatic. PET data, together with histological results and clinical course were re-evaluated retrospectively. Maximum standardised uptake values (SUVmax) and lesion-to-liver ratio were assessed. RESULTS: A total of 104 examinations were performed. Mean age at first PET was 13.5 years (2.6-22.6). Eight patients had at least one malignant lesion; four of these patients were asymptomatic. Two of four symptomatic patients died, while all patients with asymptomatic malignant lesions are alive. All malignant tumours could be identified by PET imaging in both symptomatic and asymptomatic patients. All lesions judged as benign by [18 F]FDG imaging and clinical judgment were either histologically benign if removed or remained clinically silent during follow-up. SUVmax of malignant and benign lesions overlapped, but no malignant lesion showed FDG uptake ≤3.15. Asymptomatic malignant lesions were detected with a sensitivity of 100%, a negative predictive value of 100% and a specificity of 45.1%. CONCLUSION: Malignant transformation of PN also occurs in asymptomatic children and adolescents. Detection of MPNST at early stages could increase the possibility of oncologically curative resections.

Thoracic Actinomycosis With Infiltration of the Spine: An Oncological Pitfall.

Thoracic actinomycosis with involvement of the vertebral column and chest wall is rare in children and may resemble malignant tumors. A 12-year-old girl was admitted to our clinic having B-symptoms, cachexia, and painful scoliosis (Karnofsky index 20%). Imaging showed a large thoracic left-sided paravertebral tumor with infiltration of the vertebrae, destruction of the chest wall and multiple intrapulmonary nodules. Initially, Ewing sarcoma was suspected and chemotherapy started without previous biopsies. Definite diagnosis of actinomycosis was established later upon histopathologic examination and successfully treated by ß-lactam antibiotics. Collectively, this case illustrates that actinomycosis can be an oncological pitfall and possible differential diagnosis.

Tumor Touch Imprints as Source for Whole Genome Analysis of Neuroblastoma Tumors.

INTRODUCTION: Tumor touch imprints (TTIs) are routinely used for the molecular diagnosis of neuroblastomas by interphase fluorescence in-situ hybridization (I-FISH). However, in order to facilitate a comprehensive, up-to-date molecular diagnosis of neuroblastomas and to identify new markers to refine risk and therapy stratification methods, whole genome approaches are needed. We examined the applicability of an ultra-high density SNP array platform that identifies copy number changes of varying sizes down to a few exons for the detection of genomic changes in tumor DNA extracted from TTIs. MATERIAL AND METHODS: DNAs were extracted from TTIs of 46 neuroblastoma and 4 other pediatric tumors. The DNAs were analyzed on the Cytoscan HD SNP array platform to evaluate numerical and structural genomic aberrations. The quality of the data obtained from TTIs was compared to that from randomly chosen fresh or fresh frozen solid tumors (n = 212) and I-FISH validation was performed. RESULTS: SNP array profiles were obtained from 48 (out of 50) TTI DNAs of which 47 showed genomic aberrations. The high marker density allowed for single gene analysis, e.g. loss of nine exons in the ATRX gene and the visualization of chromothripsis. Data quality was comparable to fresh or fresh frozen tumor SNP profiles. SNP array results were confirmed by I-FISH. CONCLUSION: TTIs are an excellent source for SNP array processing with the advantage of simple handling, distribution and storage of tumor tissue on glass slides. The minimal amount of tumor tissue needed to analyze whole genomes makes TTIs an economic surrogate source in the molecular diagnostic work up of tumor samples.

The genetic tumor background is an important determinant for heterogeneous MYCN-amplified neuroblastoma.

Amplification of MYCN is the signature genetic aberration of 20-25% of neuroblastoma and a stratifying marker associated with aggressive tumor behavior. The detection of heterogeneous MYCN amplification (hetMNA) poses a diagnostic dilemma due to the uncertainty of its relevance to tumor behavior. Here, we aimed to shed light on the genomic background which permits hetMNA in neuroblastoma and tied the occurrence to other stratifying markers and disease outcome. We performed SNP analysis using Affymetrix Cytoscan HD arrays on 63 samples including constitutional DNA, tumor, bone marrow and relapse samples of 26 patients with confirmed hetMNA by MYCN-FISH. Tumors of patients ≤18m were mostly aneuploid with numeric chromosomal aberrations (NCAs), presented a prominent MNA subclone and carried none or a few segmental chromosomal aberrations (SCAs). In older patients, tumors were mostly di- or tetraploid, contained a lower number of MNA cells and displayed a multitude of SCAs including concomitant 11q deletions. These patients often suffered disease progression, tumor dissemination and relapse. Restricted to aneuploid tumors, we detected chromosomes with uniparental di- or trisomy (UPD/UPT) in almost every sample. UPD11 was exclusive to tumors of younger patients whereas older patients featured UPD14. In this study, the MNA subclone appears to be constraint by the tumor environment and thus less relevant for tumor behavior in aggressive tumors with a high genomic instability and many segmental aberrations. A more benign tumor background and lower tumor stage may favor an outgrowth of the MNA clone but tumors generally responded better to treatment.

Fetal diffusion tensor quantification of brainstem pathology in Chiari II malformation.

OBJECTIVES: This prenatal MRI study evaluated the potential of diffusion tensor imaging (DTI) metrics to identify changes in the midbrain of fetuses with Chiari II malformations compared to fetuses with mild ventriculomegaly, hydrocephalus and normal CNS development. METHODS: Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated from a region of interest (ROI) in the midbrain of 46 fetuses with normal CNS, 15 with Chiari II malformations, eight with hydrocephalus and 12 with mild ventriculomegaly. Fetuses with different diagnoses were compared group-wise after age-matching. Axial T2W-FSE sequences and single-shot echo planar DTI sequences (16 non-collinear diffusion gradient-encoding directions, b-values of 0 and 700 s/mm(2), 1.5 Tesla) were evaluated retrospectively. RESULTS: In Chiari II malformations, FA was significantly higher than in age-matched fetuses with a normal CNS (p = .003), while ADC was not significantly different. No differences in DTI metrics between normal controls and fetuses with hydrocephalus or vetriculomegaly were detected. CONCLUSIONS: DTI can detect and quantify parenchymal alterations of the fetal midbrain in Chiari II malformations. Therefore, in cases of enlarged fetal ventricles, FA of the fetal midbrain may contribute to the differentiation between Chiari II malformation and other entities. KEY POINTS: • FA in the fetal midbrain is elevated in Chiari II malformations. • FA is not elevated in hydrocephalus and mild ventriculomegaly without Chiari II. • Measuring FA may help distinguish different causes for enlarged ventricles prenatally. • Elevated FA may aid in the diagnosis of open neural tube defects. • Elevated FA might contribute to stratification for prenatal surgery in Chiari II.

Superficial desmoid tumors: MRI and ultrasound imaging characteristics.

OBJECTIVES: To describe the imaging characteristics of superficial desmoid tumors using magnetic resonance imaging (MRI) and high-resolution sonography (HRUS). METHODS: We retrospectively examined 18 patients (12 females and 6 males) with histologically proven superficial desmoids. Fourteen patients received MRI examinations, while 12 patients were examined with HRUS. The lesions were assessed with regard to location, muscular fascia involvement, and spread into the subcutaneous fatty tissue septa, adjacent muscle, and bone. In addition, size, shape, signal intensity/echogenicity relative to muscle, amount of collagen components, Doppler vascularity on HRUS and the degree of contrast enhancement in MRI were evaluated. RESULTS: Altogether there were 20 subcutaneous lesions: six involved the chest wall and the breasts, five the hip, four each the shoulder and the flank, and one the abdominal wall. All but three lesions showed a stellar-type configuration with multiple irregular sun-burst-like extensions along the fascial planes and septa of the subcutaneous fat tissue. The extensions spread away from the main tumor focus, and in nine lesions, these extensions reached the cutis. The remaining three lesions had a spindle shape and also presented extensions along the fascial planes. Another imaging feature in all lesions was the presence of variable amounts of collagen components, with typical low signal on MRI and/or fibrillar hyperechoic appearance in HRUS. CONCLUSION: The distinctive imaging features of collagen components associated with sun-burst-like extensions in our sample of superficial desmoids are valuable diagnostic clues in the challenging non-invasive differential diagnosis of these tumors.

Diffusion tensor tractography for the surgical management of peripheral nerve sheath tumors.

OBJECT Peripheral nerve sheath tumors (PNSTs) are uncommon but bear a significant risk of malignancy. High-resolution MRI is the standard technique for characterizing PNSTs. However, planning the appropriate extent of resection and subsequent reconstructive strategies is highly dependent on the intraoperative findings because preoperative MRI evaluation can be insufficient. Diffusion tensor tractography (DTT) represents a recently developed advanced MRI technique that reveals the microstructure of tissues based on monitoring the random movement of water molecules. DTT has the potential to provide diagnostic insights beyond conventional MRI techniques due to its mapping of specific fibrillar nerve structures. Here, DTT was applied to evaluate PNSTs and to examine the usefulness of this method for the correct delineation of tumor and healthy nerve tissue and the value of this information in the preoperative planning of surgical interventions. METHODS In this prospective study, patients with the clinical symptoms of a PNST were investigated using DTT 3-Tesla MRI scans. Image data processing and tractography were performed using the FACT (fiber assessment by continuous tracking) algorithm and multiple-regions-of-interest approach. The surgical findings were then compared with the results of the DTT MRI scans. Preoperative fascicle visualization and the correlation with the intraoperative findings were graded. RESULTS In a 21-month period, 12 patients with PNSTs were investigated (7 female and 5 male patients with a mean age of 46.2 ± 19.2 years). All patients underwent surgical removal of the tumor. Schwannoma was the most common benign histopathological finding (n = 7), whereas 2 malignant lesions were detected. In 10 of 12 patients, good preoperative nerve fascicle visualization was achieved using DTT scans. In 9 of 10 patients with good preoperative fascicle visualization, good intraoperative correlation between the DTT scans and surgical anatomy was found. CONCLUSIONS DTT properly visualizes the peripheral nerve fascicles and their correct anatomical relation to PNST. DTT represents a promising new method for the preinterventional planning of nerve tumor resection.

Hemoglobin, alkalic phosphatase, and C-reactive protein predict the outcome in patients with liposarcoma.

Data on prognostic biomarkers in soft tissue sarcomas are scarce. The aim of the study was to define prognostic markers in patients with a liposarcoma, a subtype of sarcoma derived from adipose tissue. We restrospectively reviewed 85 patients with liposarcoma treated at our department from May 1994 to October 2011. Kaplan-Meier curves, uni-, and multivariable Cox proportional hazard models and competing risk analysis were performed to evaluate the association between putative biomarkers with disease-specific and overall survival. We observed a significant association between both alkalic phosphatase (ALP; subhazard ratio [SHR] per 1 unit increase: 1.35; 95%CI 1.10-1.65; p = 0.005) and C-reactive protein (CRP; SHR per 1 mg/dl increase: 2,57; 95%CI 1.36-4,86; p = 0.004) with disease-specific survival. Hemoglobin (Hb) (HR per 1 g/dl increase: 065; 95%CI 0.48-0.87; p = 0.003) was associated with overall survival. These associations prevailed after multivariable adjustment for AJCC tumor stage. This study identifies CRP and ALP as novel independent predictors of disease-specific survival in patients with liposarcoma.

Use of diagnostic dynamic contrast-enhanced (DCE)-MRI for targeting of soft tissue tumour biopsies at 3T: preliminary results.

OBJECTIVES: To test the feasibility and accuracy of MR-guided soft tissue tumour biopsy at 3T, using the dynamic contrast-enhanced (DCE) information from staging MRI for intralesional targeting. METHODS: After obtaining written informed consent for this institutional review board-approved study, 53 patients with suspected soft tissue tumours prospectively underwent preoperative staging MRI at 3T, including DCE, and subsequent MR-guided core needle biopsy. In 44/53 cases, DCE was heterogeneous and was used for intralesional biopsy targeting. Surgical, whole-specimen histology was used as the gold standard in 43/44 patients and revealed 42 soft tissue tumours (24 men; 18 women; mean age, 52 years; range, 19 - 84). RESULTS: Final surgical histology revealed eight benign lesions, six tumours of intermediate dignity, and 28 malignancies. All malignancies had shown heterogeneous DCE. The diagnostic yield of the biopsies was 100% (42/42). Histological accuracy rates of biopsy were 100% in predicting the dignity (42/42; 95% CI [0.916 - 1.000]), 95.2% for the tissue-specific entity (40/42; 95% CI [0.847 - 0.987]), and 90.5% for the tumour grade (38/42; 95% CI [0.779 - 0.962]). CONCLUSIONS: Our preliminary study indicates that biopsy of soft tissue tumours can be performed accurately and safely with DCE targeted MR-guidance at 3T, using a combined staging/biopsy MRI protocol. KEY POINTS: • MR-guided soft tissue tumour biopsy using DCE for intralesional targeting is feasible. • Targeting by staging-MRI allows reliable planning of the biopsy approach. • The method seems accurate and safe as a combined staging/biopsy procedure in outpatients. • DCE-targeted biopsy seems useful in challenging large and heterogeneous tumours.