Bernadette Liegl-Atzwanger

Somatic mosaic IDH1 and IDH2 mutations are associated with enchondroma and spindle cell hemangioma in Ollier disease and Maffucci syndrome

Ollier disease and Maffucci syndrome are non-hereditary skeletal disorders characterized by multiple enchondromas (Ollier disease) combined with spindle cell hemangiomas (Maffucci syndrome). We report somatic heterozygous mutations in IDH1 (c.394C>T encoding an R132C substitution and c.395G>A encoding an R132H substitution) or IDH2 (c.516G>C encoding R172S) in 87% of enchondromas (benign cartilage tumors) and in 70% of spindle cell hemangiomas (benign vascular lesions). In total, 35 of 43 (81%) subjects with Ollier disease and 10 of 13 (77%) with Maffucci syndrome carried IDH1 (98%) or IDH2 (2%) mutations in their tumors. Fourteen of 16 subjects had identical mutations in separate lesions. Immunohistochemistry to detect mutant IDH1 R132H protein suggested intraneoplastic and somatic mosaicism. IDH1 mutations in cartilage tumors were associated with hypermethylation and downregulated expression of several genes. Mutations were also found in 40% of solitary central cartilaginous tumors and in four chondrosarcoma cell lines, which will enable functional studies to assess the role of IDH1 and IDH2 mutations in tumor formation.

The lymphocyte/monocyte ratio predicts poor clinical outcome and improves the predictive accuracy in patients with soft tissue sarcomas

Increasing evidence indicates the involvement of inflammation and coagulation in cancer progression and metastases. Inflammatory biomarkers hold great promise for improving the predictive ability of existing prognostic tools in cancer patients. In the present study, we investigated several inflammatory indices with regard to their prognostic relevance for predicting clinical outcome in soft tissue sarcoma (STS) patients. Three hundred and forty STS patients were divided into a training set (n = 170) and a validation set (n = 170). Besides well‐established clinico‐pathological prognostic factors, we evaluated the prognostic value of the neutrophil/lymphocyte (N/L) ratio, the lymphocyte/monocyte (L/M) ratio and the platelet/lymphocyte (P/L) ratio using Kaplan–Meier curves and univariate as well as multivariate Cox regression models. Additionally, we developed a nomogram by supplementing the L/M ratio to the well‐established Kattan nomogram and evaluated the predictive accuracy of this novel nomogram by applying calibration and Harrells concordance index (c‐index). In multivariate analysis, a low L/M ratio was significantly associated with decreased CSS and DFS (HR = 0.41, 95% CI = 0.18–0.97, p = 0.043; HR = 0.39, 95% CI = 0.16–0.91, p = 0.031, respectively) in the training set. Using the validation set for confirmation, we found also in multivariate analysis an independent value for CSS (HR = 0.33, 95% CI = 0.12–0.90, p = 0.03) and for DFS (HR = 0.36, 95% CI = 0.16–0.79, p = 0.01). The estimated c‐index was 0.74 using the original Kattan nomogram and 0.78 when the L/M ratio was added. Our study reports for the first time that the pre‐operative L/M ratio represents a novel independent prognostic factor for prediction the clinical outcome in STS patients. This easily determinable biomarker might be helpful in improved individual risk assessment.

Elevated preoperative neutrophil/lymphocyte ratio is associated with poor prognosis in soft-tissue sarcoma patients.

Background:Recent data indicate that tumour microenvironment, which is influenced by inflammatory cells, has a crucial role in cancer progression and clinical outcome of patients. In the present study, we investigated the prognostic relevance of preoperative neutrophil/lymphocyte (N/L) ratio on time to tumour recurrence (TTR) and overall survival (OS) in soft-tissue sarcoma (STS) patients who underwent curative surgical resection.Methods:In all, 260 STS patients were included in this retrospective study. Kaplan–Meier curves and multivariate Cox proportional models were calculated for TTR and OS.Results:In univariate analysis, elevated N/L ratio was significantly associated with decreased TTR (hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.30–4.14; P=0.005) and remained significant in the multivariate analysis (HR, 1.98; 95%CI, 1.05–3.71; P=0.035). Patients with elevated N/L ratio showed a median TTR of 77.9 months. In contrast, patients with low N/L ratio had a median TTR of 99.1 months. Regarding OS, elevated N/L ratio was also significantly associated with decreased survival in univariate analysis (HR, 2.90; 95%CI, 1.82–4.61; P=0.001) and remained significant in multivariate analysis (HR, 1.88; 95%CI, 1.14–3.12; P=0.014).Conclusion:In conclusion, our findings suggest that an elevated preoperative N/L ratio predicts poor clinical outcome in STS patients and may serve as a cost-effective and broadly available independent prognostic biomarker.

Aldehyde Dehydrogenase 1, a Potential Marker for Cancer Stem Cells in Human Sarcoma

Tumors contain a small population of cancer stem cells (CSC) proposed to be responsible for tumor maintenance and relapse. Aldehyde dehydrogenase 1 (ALDH1) activity has been used as a functional stem cell marker to isolate CSCs in different cancer types. This study used the Aldefluor® assay and fluorescence-activated cell sorting (FACS) analysis to isolate ALDH1high cells from five human sarcoma cell lines and one primary chordoma cell line. ALDH1high cells range from 0.3% (MUG-Chor1) to 4.1% (SW-1353) of gated cells. Immunohistochemical staining, analysis of the clone formation efficiency, and xCELLigence microelectronic sensor technology revealed that ALDH1high cells from all sarcoma cell lines have an increased proliferation rate compared to ALDH1low cells. By investigating of important regulators of stem cell biology, real-time RT-PCR data showed an increased expression of c-Myc, β-catenin, and SOX-2 in the ALDH1high population and a significant higher level of ABCG2. Statistical analysis of data demonstrated that ALDH1high cells of SW-982 and SW-1353 showed higher resistance to commonly used chemotherapeutic agents like doxorubicin, epirubicin, and cisplatin than ALDH1low cells. This study demonstrates that in different sarcoma cell lines, high ALDH1 activity can be used to identify a subpopulation of cells characterized by a significantly higher proliferation rate, increased colony forming, increased expression of ABC transporter genes and stemness markers compared to control cells. In addition, enhanced drug resistance was demonstrated.

Safety and efficacy of regorafenib in patients with advanced soft tissue sarcoma (REGOSARC): a randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND Regorafenib is a multikinase inhibitor with proven activity in refractory gastrointestinal stromal tumours and chemotherapy-refractory advanced colorectal cancers. We assessed this agents efficacy and safety in patients with metastatic soft tissue sarcomas previously treated with anthracycline. METHODS In this randomised, double-blind, phase 2 trial undertaken in France and Austria, we enrolled patients aged 18 years and older with advanced soft tissue sarcomas who had received previous doxorubicin or other anthracycline treatment. These patients were randomly assigned (1:1) into one of the following four cohorts: liposarcoma, leiomyosarcoma, synovial sarcoma, and other sarcomas. Participants were treated with oral regorafenib (160 mg per day 3 weeks on and 1 week off) or matched placebo. Patients receiving placebo were offered optional crossover in case of centrally confirmed disease progression. The random allocation schedule was computer-generated with permuted blocks of four patients, with two stratification factors: country (France or Austria) and previous exposure to pazopanib (yes or no). Eligibility criteria included patients with histologically proven advanced and inoperable soft tissue sarcomas with intolerance or failure to doxorubicin or other anthracycline-based chemotherapy and at least one unidimensionally or bidimensionally measurable lesion according to Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). The primary endpoint was RECIST-based progression-free survival after central radiological review in the intention-to-treat population. Patients, physicians, and radiologists of the panel were masked to treatment allocation. This study is still open for recruitment for an additional stratum (patients previously treated with pazopanib) and registered with ClinicalTrials.gov, NCT01900743. FINDINGS From Aug 5, 2013, to Nov 26, 2014, 182 patients were randomly assigned to one of four cohorts and included in the final analysis. At the cutoff date (Jan 7, 2016), the number of required events was reached for the four cohorts. In the liposarcoma cohort, progression-free survival was 1·1 months (95% CI 0·9-2·3) with regorafenib versus 1·7 months (0·9-1·8) with placebo (HR 0·89 [95% CI 0·48-1·64] p=0·70). In the leiomyosarcoma cohort, progression-free survival was 3·7 months (95% CI 2·5-5·0) with regorafenib versus 1·8 (1·0-2·8) months with placebo (HR 0·46 [95% CI 0·46-0·80] p=0·0045). In the synovial sarcoma cohort, progression-free survival was 5·6 months (95% CI 1·4-11·6) with regorafenib versus 1·0 (0·8-1·4) with placebo (HR 0·10 [95% CI 0·03-0·35] p<0·0001). In the other sarcoma cohort, progression-free survival was 2·9 months (95% CI 1·0-7·8) with regorafenib versus 1·0 (0·9-1·9) with placebo (HR 0·46 [95% CI 0·25-0·81] p=0·0061). Before crossover, the most common clinically significant grade 3 or higher adverse events were arterial hypertension (17 [19%] events in the 89 patients in the regorafenib group vs two [2%] events in the 92 patients in the placebo group), hand and foot skin reaction (14 [15%] vs no events) and asthenia (12 [13%] vs six [6%]). One treatment-related death occurred in the regorafenib group due to liver failure. INTERPRETATION Regorafenib has an important clinical antitumour effect in non-adipocytic soft tissue sarcomas, improving progression-free survival. Regorafenib should be further evaluated in this setting, and its therapeutic role has to be defined in the context of the growing therapeutic armamentarium, already including one approved multikinase inhibitor, pazopanib. FUNDING Bayer HealthCare.

Validation of the prognostic relevance of plasma C-reactive protein levels in soft-tissue sarcoma patients.

Background:The concept of the involvement of systemic inflammation in cancer progression and metastases has gained attraction within the past decade. C-reactive protein (CRP), a non-specific blood-based marker of the systemic inflammatory response, has been associated with decreased survival in several cancer types. The aim of the present study was to validate the prognostic value of pre-operative plasma CRP levels on clinical outcome in a large cohort of soft-tissue sarcoma (STS) patients.Methods:Three hundred and four STS patients, operated between 1998 and 2010, were retrospectively evaluated. CRP levels and the impact on cancer-specific survival (CSS), disease-free survival (DFS) and overall survival (OS) were assessed using Kaplan–Meier curves and univariate as well as multivariate Cox proportional models. Additionally, we developed a nomogram by supplementing the plasma CRP level to the well-established Kattan nomogram and evaluated the improvement of predictive accuracy of this novel nomogram by applying calibration and Harrell’s concordance index (c-index).Results:An elevated plasma CRP level was significantly associated with established prognostic factors, including age, tumour grade, size and depth (P<0.05). In multivariate analysis, increased CRP levels were significantly associated with a poor outcome for CSS (HR=2.05; 95% CI=1.13–3.74; P=0.019) and DFS (HR=1.88; 95% CI=1.07–3.34; P=0.029). The estimated c-index was 0.74 using the original Kattan nomogram and 0.77 when the plasma CRP level was added.Conclusion:An elevated pre-operative CRP level represents an independent prognostic factor that predicts poor prognosis and improves the predictive ability of the Kattan nomogram in STS patients. Our data suggest to further prospectively validate its potential utility for individual risk stratification and clinical management of STS patients.

FUS rearrangements are rare in 'pure' sclerosing epithelioid fibrosarcoma

Several recent reports have described low-grade fibromyxoid sarcoma with sclerosing epithelioid fibrosarcoma-like areas. We evaluated cases of pure sclerosing epithelioid fibrosarcoma lacking areas of low-grade fibromyxoid sarcoma for FUS rearrangement to determine whether this entity could be related to low-grade fibromyxoid sarcoma. Available formalin-fixed paraffin-embedded tissue of 27 sclerosing epithelioid fibrosarcoma from 25 patients was retrieved and tabulated with clinical information. Unstained slides from formalin-fixed paraffin-embedded blocks were prepared and fluorescence in-situ hybridization was performed using a commercial FUS break-apart probe. The median patient age at presentation was 50 (range, 14–78) years, with 14 males and 10 females. Sclerosing epithelioid fibrosarcoma most commonly involved the extremities (n=8) or chest (n=6). Sixteen patients had a median follow-up of 17 (range, 1–99) months; seven were alive and well at 12 (range, 5–30) months; three alive with disease at 28 (range, 9–99) months; five dead of disease at a median of 22 (range, 1–36) months and one was dead of unknown causes. Twelve patients were known to have metastases; the most common site was lung (n=7), followed by bone (n=3), lymph nodes (n=2) and peritoneum (n=1). Only 2 of 22 (9%) analyzable cases of sclerosing epithelioid fibrosarcoma showed rearrangement in the FUS locus by fluorescence in-situ hybridization. Although cytogenetically confirmed low-grade fibromyxoid sarcoma can have sclerosing epithelioid fibrosarcoma-like areas, FUS rearrangement, which is characteristic of low-grade fibromyxoid sarcoma, appears to be relatively rare in pure sclerosing epithelioid fibrosarcoma.

DNA methylation heterogeneity defines a disease spectrum in Ewing sarcoma

Developmental tumors in children and young adults carry few genetic alterations, yet they have diverse clinical presentation. Focusing on Ewing sarcoma, we sought to establish the prevalence and characteristics of epigenetic heterogeneity in genetically homogeneous cancers. We performed genome-scale DNA methylation sequencing for a large cohort of Ewing sarcoma tumors and analyzed epigenetic heterogeneity on three levels: between cancers, between tumors, and within tumors. We observed consistent DNA hypomethylation at enhancers regulated by the disease-defining EWS-FLI1 fusion protein, thus establishing epigenomic enhancer reprogramming as a ubiquitous and characteristic feature of Ewing sarcoma. DNA methylation differences between tumors identified a continuous disease spectrum underlying Ewing sarcoma, which reflected the strength of an EWS-FLI1 regulatory signature and a continuum between mesenchymal and stem cell signatures. There was substantial epigenetic heterogeneity within tumors, particularly in patients with metastatic disease. In summary, our study provides a comprehensive assessment of epigenetic heterogeneity in Ewing sarcoma and thereby highlights the importance of considering nongenetic aspects of tumor heterogeneity in the context of cancer biology and personalized medicine.

Screening for potential targets for therapy in mesenchymal, clear cell, and dedifferentiated chondrosarcoma reveals Bcl-2 family members and TGFβ as potential targets.

The mesenchymal, clear cell, and dedifferentiated chondrosarcoma subtypes are extremely rare, together constituting 10% to 15% of all chondrosarcomas. Their poor prognosis and lack of efficacious treatment emphasizes the need to elucidate the pathways playing a pivotal role in these tumors. We constructed tissue microarrays containing 42 dedifferentiated, 23 clear cell, and 23 mesenchymal chondrosarcomas and performed immunohistochemistry to study the expression of growth plate-signaling molecules and molecules shown to be involved in conventional chondrosarcoma. We observed high expression of SOX-9 and FGFR-3, as well as aberrant cellular localization of heparan sulfate proteoglycans, in all subtypes. TGFβ signaling through p-SMAD2 and PAI-1 was highly active in all chondrosarcoma subtypes, which suggests that TGFβ inhibitors as a possible therapeutic strategy in rare chondrosarcoma subtypes. As in conventional chondrosarcoma, antiapoptotic proteins (Bcl-2, and/or Bcl-xl) were highly expressed in all subtypes. Inhibition with the BH-3 mimetic ABT-737 rendered dedifferentiated chondrosarcoma cell lines sensitive to doxorubicin or cisplatin. Our data indicate that antiapoptotic proteins may play an important role in chemoresistance, suggesting a promising role for targeting Bcl-2 family members in chondrosarcoma treatment, irrespective of the subtype.

Noninflammatory Pseudotumor Simulating Venous Thrombosis After Metal-on-Metal Hip Resurfacing

Metal-on-metal hip resurfacing has become a widespread procedure, especially in young, physically active patients. Pseudotumor is a new complication that can occur after hip resurfacing and metal-on-metal total hip arthroplasty (THA). This article presents a case of a 37-year-old woman who underwent metal-on-metal resurfacing of the left hip for symptomatic osteoarthritis. Twelve months following implantation, the patient reported painless swelling of the left lower leg. There was no clinical evidence of a deep venous thrombosis. Ultrasound and computed tomography showed a solid cystic lesion in the iliopsoas muscle, which communicated with the hip joint and compressed the external iliac vein. As a consequence, the cystic lesion was resected marginally. A few months later, the patient reported some discomfort in the groin and symptoms of instability, metallic clicking, and a restricted range of motion. Clinical and radiological examination revealed normal findings. Determining the serum concentration of cobalt and chromium revealed high increased levels of these metal ions. Ten months following excision of the pseudotumor, the patient reported recurrent swelling of the left lower leg. Computed tomography of the affected area showed a lobulated cystic formation; therefore, a relapse was suspected. At the second revision, the mass was excised and the implant was revised to a conventional ceramic-on-ceramic THA. At 30-month follow-up, the patient was doing well and there were no signs of local recurrence. Additionally, the metal ion levels of cobalt and chromium in the blood had significantly decreased.