Rendering-Based Video-CT Registration with Physical Constraints for Image-Guided Endoscopic Sinus Surgery

We present a system for registering the coordinate frame of an endoscope to pre- or intra- operatively acquired CT data based on optimizing the similarity metric between an endoscopic image and an image predicted via rendering of CT. Our method is robust and semi-automatic because it takes account of physical constraints, specifically, collisions between the endoscope and the anatomy, to initialize and constrain the search. The proposed optimization method is based on a stochastic optimization algorithm that evaluates a large number of similarity metric functions in parallel on a graphics processing unit. Images from a cadaver and a patient were used for evaluation. The registration error was 0.83 mm and 1.97 mm for cadaver and patient images respectively. The average registration time for 60 trials was 4.4 seconds. The patient study demonstrated robustness of the proposed algorithm against a moderate anatomical deformation.

Molecular profiling of myeloid progenitor cells in multi-mutated advanced systemic mastocytosis identifies KIT D816V as a distinct and late event

To explore the molecular profile and its prognostic implication in systemic mastocytosis (SM), we analyzed the mutation status of granulocyte-macrophage colony-forming progenitor cells (CFU-GM) in patients with KIT D816V(+) indolent SM (ISM, n=4), smoldering SM (SSM, n=2), aggressive SM (ASM, n=1), SM with associated clonal hematologic non-mast cell lineage disorder (SM-AHNMD, n=5) and ASM-AHNMD (n=7). All patients with (A)SM-AHNMD (n=12) carried 1-4 (median 3) additional mutations in 11 genes tested, most frequently TET2, SRSF2, ASXL1, CBL and EZH2. In multi-mutated (A)SM-AHNMD, KIT D816V(+) single-cell-derived CFU-GM colonies were identified in 8/12 patients (median 60%, range 0-95). Additional mutations were identified in CFU-GM colonies in all patients, and logical hierarchy analysis indicated that mutations in TET2, SRSF2 and ASXL1 preceded KIT D816V. In ISM/SSM, no additional mutations were detected and CFU-GM colonies were exclusively KIT D816V(-). These data indicate that (a) (A)SM-AHNMD is a multi-mutated neoplasm, (b) mutations in TET2, SRSF2 or ASXL1 precede KIT D816V in ASM-AHNMD,

Proposed diagnostic algorithm for patients with suspected mastocytosis: a proposal of the European Competence Network on Mastocytosis

Mastocytosis is an emerging differential diagnosis in patients with more or less specific mediator-related symptoms. In some of these patients, typical skin lesions are found and the diagnosis of mastocytosis can be established. In other cases, however, skin lesions are absent, which represents a diagnostic challenge. In the light of this unmet need, we developed a diagnostic algorithm for patients with suspected mastocytosis. In adult patients with typical lesions of mastocytosis in the skin, a bone marrow (BM) biopsy should be considered, regardless of the basal serum tryptase concentration. In adults without skin lesions who suffer from mediator-related or other typical symptoms, the basal tryptase level is an important parameter. In those with a slightly increased tryptase level, additional investigations, including a sensitive KIT mutation analysis of blood leucocytes or measurement of urinary histamine metabolites, may be helpful. In adult patients in whom (i) KIT D816V is detected and/or (ii) the basal serum tryptase level is clearly increased (>25-30 ng/ml) and/or (iii) other clinical or laboratory features suggest the presence of 'occult' mastocytosis or another haematologic neoplasm, a BM investigation is recommended. In the absence of KIT D816V and other signs or symptoms of mastocytosis or another haematopoietic disease, no BM investigation is required, but the clinical course and tryptase levels are monitored in the follow-up. In paediatric patients, a BM investigation is usually not required, even if the tryptase level is increased. Although validation is required, it can be expected that the algorithm proposed herein will facilitate the management of patients with suspected mastocytosis and help avoid unnecessary referrals and investigations.

Refined diagnostic criteria and classification of mast cell leukemia (MCL) and myelomastocytic leukemia (MML): a consensus proposal

Mast cell leukemia (MCL), the leukemic manifestation of systemic mastocytosis (SM), is characterized by leukemic expansion of immature mast cells (MCs) in the bone marrow (BM) and other internal organs; and a poor prognosis. In a subset of patients, circulating MCs are detectable. A major differential diagnosis to MCL is myelomastocytic leukemia (MML). Although criteria for both MCL and MML have been published, several questions remain concerning terminologies and subvariants. To discuss open issues, the EU/US-consensus group and the European Competence Network on Mastocytosis (ECNM) launched a series of meetings and workshops in 2011-2013. Resulting discussions and outcomes are provided in this article. The group recommends that MML be recognized as a distinct condition defined by mastocytic differentiation in advanced myeloid neoplasms without evidence of SM. The group also proposes that MCL be divided into acute MCL and chronic MCL, based on the presence or absence of C-Findings. In addition, a primary (de novo) form of MCL should be separated from secondary MCL that typically develops in the presence of a known antecedent MC neoplasm, usually aggressive SM (ASM) or MC sarcoma. For MCL, an imminent prephase is also proposed. This prephase represents ASM with rapid progression and 5%-19% MCs in BM smears, which is generally accepted to be of prognostic significance. We recommend that this condition be termed ASM in transformation to MCL (ASM-t). The refined classification of MCL fits within and extends the current WHO classification; and should improve prognostication and patient selection in practice as well as in clinical trials.

Oncostatin M is a FIP1L1/PDGFRA-dependent mediator of cytokine production in chronic eosinophilic leukemia

BACKGROUND

Chronic eosinophilic leukemia (CEL) is a myeloproliferative neoplasm characterized by expansion of neoplastic eosinophils, tissue infiltration, and organ damage. In a subset of these patients, the FIP1L1/PDGFRA (F/P) oncoprotein is detectable. F/P exhibits constitutive tyrosine kinase activity and activates a number of signaling pathways. So far, however, little is known about the role of F/P-dependent proteins in the pathogenesis of CEL.

METHODS

A screen for F/P-dependent cytokines was performed in growth factor-dependent human cell lines lentivirally transduced with F/P. Signal transduction pathways were characterized in Ba/F3 cells with doxycycline-inducible expression of F/P and in EOL-1 cells. Cytokine expression was confirmed in patients' material by immunohistochemistry, immunofluorescence, and confocal microscopy. Gene expression analysis, proliferation assays, and chemotaxis assays were used to elucidate paracrine interactions between neoplastic eosinophils and stromal cells.

RESULTS

We show that F/P upregulates expression of oncostatin M (OSM) in various cell line models in a STAT5-dependent manner. Correspondingly, neoplastic eosinophils in the bone marrow were found to overexpress OSM. OSM derived from F/P + cells stimulated proliferation of stromal cells. Moreover, OSM-containing supernatants from F/P + cells were found to upregulate production of stromal cell-derived factor-1 (SDF-1)/CXCL12 in human fibroblasts. SDF-1, in turn, induced migration of EOL-1 cells in a dose-dependent manner.

CONCLUSIONS

We have identified a F/P-driven paracrine interaction between neoplastic eosinophils and stromal cells that may contribute to tissue fibrosis and accumulation of neoplastic eosinophils in CEL.

Non-Hodgkin lymphoma in children and adolescents

Until the 1970s, childhood non-Hodgkin lymphoma (NHL) was an almost incurable disease. Since then tremendous progress has been made. In this article the contributions of the Berlin-Frankfurt-Münster (BFM)-group clinical studies to the development of efficacious treatment for childhood and adolescent NHL will be described.From 1975 to 2001, 6 consecutive cooperative multicenter studies were conducted into which a total of 2 190 protocol patients were enrolled. The probability of event-free survival (pEFS) at 5 years was 60% in the first study and increased to 84% in study NHL-BFM 95 while the overall survival probability increased from 65 to 89%. Landmarks in the development were the recognitions that childhood NHL is a heterogeneous disease and different biological subtypes require specifically adapted treatment strategies, that within subtypes the required treatment intensity varies significantly and that the appropriate prognostic parameters for stratification of treatment intensity differ between different NHL subentities. With increasing efficacy of chemotherapy local therapy modalities were almost completely abandoned. Central nervous system (CNS) irradiation for prevention of CNS relapses was, with few exceptions, replaced by CNS directed chemotherapy. The key role of methotrexate and its optimal risk adapted dose and administration schedule for treatment of mature B-cell neoplasm's could be enlightened and the first phase 2 study proving the activity of the anti-CD20 monoclonal antibody Rituximab as targeted therapy for pediatric B-NHL was successfully conducted.

Key treatment questions in childhood acute lymphoblastic leukemia: results in 5 consecutive trials performed by the ALL-BFM study group from 1981 to 2000

Between 1981 and 2000, 6 609 children (<18 years of age) were treated in 5 consecutive trials of the Berlin-Frankfurt-Münster (BFM) study group for childhood acute lymphoblastic leukemia (ALL). Patients were treated in up to 82 centers in Germany, Austria, and Switzerland. Probability of 10-year event-free survival (survival) improved from 65% (77%) in study ALL-BFM 81-78% (85%) in ALL-BFM 95. In parallel to relapse reduction, major efforts focused on reducing acute and late toxicity through advanced risk adaptation of treatment. The major findings derived from these ALL-BFM trials were as follows: 1) preventive cranial radiotherapy could be safely reduced to 12 Gy in T-ALL and high-risk ALL patients and eliminated in non-high-risk non-T-ALL patients, if it was replaced by high-dose and intrathecal methotrexate; 2) omission of delayed reintensification severely impaired outcome of low-risk patients; 3) 6 months less maintenance therapy caused an increase in systemic relapses; 4) slow response to an initial 7-day prednisone window was identified as adverse prognostic factor; 5) condensed induction therapy resulted in a significant improvement of outcome; 6) the daunorubicin dose in induction could be safely reduced in low-risk patients; 7) intensification of consolidation/reintensification treatment led to considerable improvement of outcome in high-risk patients.

Mutations and prognosis in primary myelofibrosis

Patient outcome in primary myelofibrosis (PMF) is significantly influenced by karyotype. We studied 879 PMF patients to determine the individual and combinatorial prognostic relevance of somatic mutations. Analysis was performed in 483 European patients and the seminal observations were validated in 396 Mayo Clinic patients. Samples from the European cohort, collected at time of diagnosis, were analyzed for mutations in ASXL1, SRSF2, EZH2, TET2, DNMT3A, CBL, IDH1, IDH2, MPL and JAK2. Of these, ASXL1, SRSF2 and EZH2 mutations inter-independently predicted shortened survival. However, only ASXL1 mutations (HR: 2.02; P<0.001) remained significant in the context of the International Prognostic Scoring System (IPSS). These observations were validated in the Mayo Clinic cohort where mutation and survival analyses were performed from time of referral. ASXL1, SRSF2 and EZH2 mutations were independently associated with poor survival, but only ASXL1 mutations held their prognostic relevance (HR: 1.4; P=0.04) independent of the Dynamic IPSS (DIPSS)-plus model, which incorporates cytogenetic risk. In the European cohort, leukemia-free survival was negatively affected by IDH1/2, SRSF2 and ASXL1 mutations and in the Mayo cohort by IDH1 and SRSF2 mutations. Mutational profiling for ASXL1, EZH2, SRSF2 and IDH identifies PMF patients who are at risk for premature death or leukemic transformation.

Lessons learned using the insertable robotic effector platform (IREP) for single port access surgery

This paper presents the preliminary evaluation of a robotic system for single port access surgery. This system may be deployed through a 15-mm incision. It deploys two surgical arms and a third arm manipulating a stereo-vision module that tracks instrument location. The paper presents the design of the robot along with experiments demonstrating the capabilities of this robot. The evaluation includes use of tasks from fundamentals of laparoscopic surgery, evaluation of telemanipulation accuracy, knot tying, and vision tracking of tools.

High activity of sorafenib in FLT3-ITD-positive acute myeloid leukemia synergizes with allo-immune effects to induce sustained responses

Preliminary evidence suggests that the multikinase inhibitor sorafenib has clinical activity in FLT3-ITD-positive (FLT3-ITD) acute myeloid leukemia (AML). However, the quality and sustainability of achievable remissions and clinical variables that influence the outcome of sorafenib monotherapy are largely undefined. To address these questions, we evaluated sorafenib monotherapy in 65 FLT3-ITD AML patients treated at 23 centers. All but two patients had relapsed or were chemotherapy-refractory after a median of three prior chemotherapy cycles. Twenty-nine patients (45%) had undergone prior allogeneic stem cell transplantation (allo-SCT). The documented best responses were: hematological remission in 24 patients (37%), bone marrow remission in 5 patients (8%), complete remission (with and without normalization of peripheral blood counts) in 15 patients (23%) and molecular remission with undetectable FLT3-ITD mRNA in 10 patients (15%), respectively. Seventeen of the patients without prior allo-SCT (47%) developed sorafenib resistance after a median treatment duration of 136 days (range, 56-270 days). In contrast, allo-SCT patients developed sorafenib resistance less frequently (38%) and significantly later (197 days, range 38-225 days; P=0.03). Sustained remissions were seen exclusively in the allo-SCT cohort. Thus, sorafenib monotherapy has significant activity in FLT3-ITD AML and may synergize with allogeneic immune effects to induce durable remissions.

Comparison of six different specimen types for Epstein-Barr viral load quantification in peripheral blood of pediatric patients after heart transplantation or after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Epstein-Barr Virus (EBV) a gamma-herpes virus is associated with a spectrum of lymphoid and epithelial malignancies including posttransplant lymphoproliferative disorders (PTLD). EBV-load measurement has been shown to be important for the monitoring of these patients. However, in contrast to the viral quantification of human immunodeficiency virus or human hepatitis C virus, the EBV-load measurement has not been completely standardized as yet.

OBJECTIVES

In this study, we compared the EBV DNA levels in whole blood (WB), plasma, peripheral mononuclear cells (PBMC) and B-cells (BC) in children and adolescents after heart transplantations (HTx) and allogeneic hematopoietic stem cell transplantations (HSCT).

STUDY DESIGN

In a period of 2 years (from May 2007 to May 2009) we collected 547 samples of 96 cardiac transplant recipients and 248 samples of 37 patients who underwent HSCT. For EBV DNA quantification we used a duplex real-time PCR (ABI Prism 7500, Applied Biosystems). Additionally, EBV-load of PBMC and BC were normalized with respect to endogenous cell DNA.

RESULTS

In both patient populations we found no significant difference of test sensitivity for the EBV detection. In PBMC as well as BC, there was a high correlation between the analysis of cells with and without normalization in both populations. Spearman's correlation coefficient ρ between PBMC without and PBMC with normalization was ρ=0.98 (P<0.0001) in patients after HTx and ρ=0.99 (P<0.0001) in patients after HSCT. Correlation between BC with and without normalization was ρ=0.98 (P<0.0001) in patients after HTx and ρ=0.995 (P<0.0001) in patients after HSCT. When comparing the different blood compartments for EBV quantification in both populations, the strongest correlations were found between the EBV DNA levels in WB and PBMC (HTx: ρ=0.93, P<0.0001; HSCT: ρ=0.81, P<0.0001) followed by PBMC and BC (HTx: ρ=0.87, P<0.0001; HSCT: ρ=0.81, P<0.0001) as well as WB and BC (HTx: ρ=0.86, P<0.0001; HSCT: ρ=0.75, P<0.0001). In contrast, the correlation coefficients between plasma and the other blood compartments (WB as well as PBMC or BC) were lower. Six patients developed seven episodes of PTLD (five patients after HTx and one after renal transplantation). Analyzing the different blood compartments, we found that a threshold of WB ≥20,000EBV-copies/ml and plasma ≥1000EBV-copies/ml had the highest sensitivities and specificities (WB: sensitivity 100%, specificity 87% and plasma: sensitivity 88%, specificity 98%).

CONCLUSION

Normalization towards an endogenous control does not seem to be necessary for EBV quantification in peripheral blood. The analysis of whole blood correlates well with B-cells and PBMC. Routine screening of EBV DNA in whole blood appeared to be a useful tool supplemented by EBV-load measurement in plasma to discriminate chronic high EBV-load carrier without risk for PTLD from those who are at risk for PTLD. Values in whole blood higher than 20,000EBV-copies/ml WB and plasma values higher than 1000EBV-copies/ml plasma indicated PTLD in our series.