Minimal residual disease and outcome characteristics in infant KMT2A-germline acute lymphoblastic leukaemia treated on the Interfant-06 protocol.

BACKGROUND: The outcome of infants with KMT2A-germline acute lymphoblastic leukaemia (ALL) is superior to that of infants with KMT2A-rearranged ALL but has been inferior to non-infant ALL patients. Here, we describe the outcome and prognostic factors for 167 infants with KMT2A-germline ALL enrolled in the Interfant-06 study. METHODS: Univariate analysis on prognostic factors (age, white blood cell count at diagnosis, prednisolone response and CD10 expression) was performed on KMT2A-germline infants in complete remission at the end of induction (EOI; n = 163). Bone marrow minimal residual disease (MRD) was measured in 73 patients by real-time quantitative polymerase chain reaction at various time points (EOI, n = 68; end of consolidation, n = 56; and before OCTADAD, n = 57). MRD results were classified as negative, intermediate (<5∗10-4), and high (≥5∗10-4). RESULTS: The 6-year event-free and overall survival was 73.9% (standard error [SE] = 3.6) and 87.2% (SE = 2.7). Relapses occurred early, within 36 months from diagnosis in 28 of 31 (90%) infants. Treatment-related mortality was 3.6%. Age <6 months was a favourable prognostic factor with a 6-year disease-free survival (DFS) of 91% (SE = 9.0) compared with 71.7% (SE = 4.2) in infants >6 months of age (P = 0.04). Patients with high EOI MRD ≥5 × 10-4 had a worse outcome (6-year DFS 61.4% [SE = 12.4], n = 16), compared with patients with undetectable EOI MRD (6-year DFS 87.9% [SE = 6.6], n = 28) or intermediate EOI MRD <5 × 10-4 (6-year DFS 76.4% [SE = 11.3], n = 24; P = 0.02). CONCLUSION: We conclude that young age at diagnosis and low EOI MRD seem favourable prognostic factors in infants with KMT2A-germline ALL and should be considered for risk stratification in future clinical trials.

Skeletal maturation, fundamental motor skills, and motor performance in preschool children.

Relationships among skeletal age (SA), body size and fundamental motor skills (FMS) and motor performance were considered in 155 boys and 159 girls 3-6 years of age. Stature and body mass were measured. SA of the hand-wrist was assessed with the Tanner-Whitehouse II 20 bone method. The Test of Gross Motor Development, 2nd edition (TGMD-2), and the Preschool Test Battery were used, respectively, to assess FMS and motor performance. Based on hierarchical regression analyses, the standardized residuals of SA on chronological age (SAsr) explained a maximum of 6.1% of the variance in FMS and motor performance in boys (ΔR2 3 , range 0.0%-6.1%) and a maximum of 20.4% of the variance in girls (ΔR2 3 , range 0.0%-20.4%) over that explained by body size and interactions of SAsr with body size (step 3). The interactions of the SAsr and stature and body mass (step 2) explained a maximum of 28.3% of the variance in boys (ΔR2 2 , range 0.5%-28.3%) and 16.7% of the variance in girls (ΔR2 2 , range 0.7%-16.7%) over that explained by body size alone. With the exception of balance, relationships among SAsr and FMS or motor performance differed between boys and girls. Overall, SA per se or interacting with body size had a relatively small influence in FMS and motor performance in children 3-6 years of age.

Polymorphisms in the ABCB1 gene and effect on outcome and toxicity in childhood acute lymphoblastic leukemia.

The membrane transporter P-glycoprotein, encoded by the ABCB1 gene, influences the pharmacokinetics of anti-cancer drugs. We hypothesized that variants of ABCB1 affect outcome and toxicity in childhood acute lymphoblastic leukemia (ALL). We studied 522 Danish children with ALL, 93% of all those eligible. Risk of relapse was increased 2.9-fold for patients with the 1199GA variant versus 1199GG (P=0.001), and reduced 61% and 40%, respectively, for patients with the 3435CT or 3435TT variants versus 3435CC (overall P=0.02). The degree of bone marrow toxicity during doxorubicin, vincristine and prednisolone induction therapy was more prominent in patients with 3435TT variant versus 3435CT/3435CC (P=0.01/P<0.0001). We observed more liver toxicity after high-dose methotrexate in patients with 3435CC variant versus 3435CT/TT (P=0.03). In conclusion, there is a statistically significant association between ABCB1 polymorphisms, efficacy and toxicity in the treatment of ALL, and ABCB1 1199G>A may be a new possible predictive marker for outcome in childhood ALL.

Structural proteins of Kaposi's sarcoma-associated herpesvirus antagonize p53-mediated apoptosis.

The tumor suppressor p53 is a central regulatory molecule of apoptosis and is commonly mutated in tumors. Kaposi's sarcoma-associated herpesvirus (KSHV)-related malignancies express wild-type p53. Accordingly, KSHV encodes proteins that counteract the cell death-inducing effects of p53. Here, the effects of all KSHV genes on the p53 signaling pathway were systematically analyzed using the reversely transfected cell microarray technology. With this approach we detected eight KSHV-encoded genes with potent p53 inhibiting activity in addition to the previously described inhibitory effects of KSHV genes ORF50, K10 and K10.5. Interestingly, the three most potent newly identified inhibitors were KSHV structural proteins, namely ORF22 (glycoprotein H), ORF25 (major capsid protein) and ORF64 (tegument protein). Validation of these results with a classical transfection approach showed that these proteins inhibited p53 signaling in a dose-dependent manner and that this effect could be reversed by small interfering RNA-mediated knockdown of the respective viral gene. All three genes inhibited p53-mediated apoptosis in response to Nutlin-3 treatment in non-infected and KSHV-infected cells. Addressing putative mechanisms, we could show that these proteins could also inhibit the transactivation of the promoters of apoptotic mediators of p53 such as BAX and PIG3. Altogether, we demonstrate for the first time that structural proteins of KSHV can counteract p53-induced apoptosis. These proteins are expressed in the late lytic phase of the viral life cycle and are incorporated into the KSHV virion. Accordingly, these genes may inhibit cell death in the productive and in the early entrance phase of KSHV infection.

[Prevalence of glaucomatous optic nerve atrophy among a working population in Germany diagnosed by a telemedical approach]. / Telemedizinische Erfassung der Prävalenz der glaukomatösen Optikusatrophie in einer arbeitenden Bevölkerungsgruppe.

PURPOSE: The aim of this study was to determine the prevalence of glaucomatous optic nerve atrophy among a working population in Germany by secondary evaluation of a study conducted to estimate the prevalence of retinal microangiopathic abnormalities by telemedical examination of the retina. PATIENTS AND METHODS: From August 2002 until January 2004 the retina and optic nerve head were examined in 19,294 Caucasians using a non-mydriatic fundus camera (Kowa, nonmyd-alpha 45), which produces colour images with 45 degrees. The images of the retina and optic nerve head were evaluated telemedically by glaucoma specialists in respect to optic nerve pathologies and microangiopathic abnormalities by a standardised procedure. Glaucomatous optic nerve atrophy was diagnosed when specific glaucomatous morphological alterations of the optic nerve head were present. A complete medical history including reported elevated intraocular pressure (IOP) and blood pressure was obtained. RESULTS: The intra-observer and inter-observer reliability were 0.884 and 0.740, respectively. Cronbach's alpha for two evaluation cycles each of two observers was 0.870. The prevalences of glaucomatous optic nerve atrophy in the different age groups were 0.07 % (45 - 49 years), 0.40 % (50 - 54 years), 0.45 % (55 - 59 years) and 0.82 % (60 - 64 years). Age could be established as an important risk factor for glaucomatous optic nerve atrophy, while no influence of gender or family history was found. CONCLUSION: Telemedical evaluation of colour images of the retina and optic nerve acquired by a non-mydriatic fundus camera allows a fast and efficient screening of many subjects with medium reliability.

The degree of myelosuppression during maintenance therapy of adolescents with B-lineage intermediate risk acute lymphoblastic leukemia predicts risk of relapse.

Drug doses, blood levels of drug metabolites and myelotoxicity during 6-mercaptopurine/methotrexate (MTX) maintenance therapy were registered for 59 adolescents (>or=10 years) and 176 non-adolescents (<10 years) with B-cell precursor acute lymphoblastic leukemia (ALL) and a white blood cell count (WBC) <50 x 10(9)/l at diagnosis. Event-free survival was lower for adolescents than non-adolescents (pEFS(12y):0.71 vs 0.83, P=0.04). For adolescents staying in remission, the mean WBC during maintenance therapy (mWBC) was related to age (r(S)=0.36, P=0.02), which became nonsignificant for those who relapsed (r(S)=0.05, P=0.9). The best-fit multivariate Cox regression model to predict risk of relapse included mWBC and thiopurine methyltransferase activity, which methylates mercaptopurine and reduces the intracellular availability of cytotoxic 6-thioguanine nucleotides (coefficient: 0.11, P=0.02). The correlation of mWBC to the risk of relapse was more pronounced for adolescents (coefficient=0.65, P=0.003) than for non-adolescents (coefficient=0.42, P=0.04). Adolescents had higher mean neutrophil counts (P=0.002) than non-adolescents, but received nonsignificantly lower mercaptopurine and MTX doses during maintenance therapy. Red blood cell MTX levels were significantly related to the dose of MTX among adolescents who stayed in remission (r(S)=0.38, P=0.02), which was not the case for those who developed a relapse (r(S)=0.15, P=0.60). Thus, compliance to maintenance therapy may influence the risk of relapse for adolescents with ALL.

Outdoor work and skin cancer incidence: a registry-based study in Bavaria.

OBJECTIVE: To analyse the association between occupational ultraviolet (UV) light exposure and skin cancer (basal cell carcinoma, BCC; squamous cell carcinoma, SCC; cutaneous malignant melanoma, CMM) based on data from the Bavarian population-based cancer registry. METHODS: The population-based cancer registry of Bavaria (Germany) provided data on incident cases of BCC, SCC, and CMM, respectively, during the period 2001 until 2005. Eleven Bavarian districts with complete skin cancer registration were included in this analysis based on 2,156,336 person years. Cases were assigned to "indoor", "mixed indoor/outdoor", and "outdoor" exposure categories according to their job title. We computed age-specific and age-adjusted incidence rates of BCC (n = 1,641), SCC (n = 499), and CMM (n = 454) by work type, and the relative risk (RR) of skin cancer occurrence for "outdoor" and "mixed indoor/outdoor" workers, respectively, compared to "indoor" workers. RESULTS: The risk of BCC was substantially elevated in male (RR, 2.9; 95% CI, 2.2-3.9) and female (RR, 2.7; 95% CI, 1.8-4.1) outdoor workers compared to male and female indoor workers, respectively. We also found an elevated risk of similar magnitude for SCC in male (RR, 2.5; 95% CI, 1.4-4.7) and female (RR, 3.6; 95% CI, 1.6-8.1) outdoor workers compared to male and female indoor workers, respectively. CMM risk was not significantly associated with outdoor work. CONCLUSION: Our study confirms previous reports on the increased risk of BCC and SCC in outdoor workers compared to indoor workers.

Polymorphisms in the novel serotonin receptor subunit gene HTR3C show different risks for acute chemotherapy-induced vomiting after anthracycline chemotherapy.

The aim of this study was to correlate chemotherapy-induced nausea and vomiting (CINV) with commonly occurring single nucleotide polymorphisms (SNP) in the 5-hydroxytryptamine receptor 3 genes (HTR3). Women with breast cancer without previous chemotherapy were eligible for this prospective study. All patients received epirubicin, with or without cyclophosphamide, and preventive medication with ondansetron and dexamethasone. The patients documented every vomiting event on an hourly basis. Real-time polymerase chain reaction (PCR) analysis was performed for the following nonsynonymous SNPs: p.Y129S (HTR3B), p.K163N (HTR3C) and p.A405G (HTR3C). The overall proportion of patients (total n = 110) who reported vomiting in the first 24 h after chemotherapy was 31.8%. The variant genotype of K163N (HTR3C) was associated with vomiting, which occurred in 50.0% (P = 0.009). Polymorphisms in the HTR3C gene could serve as a predictive factor for CINV in patients undergoing moderately emetogenic chemotherapy.

Comparison of classifiers applied to confocal scanning laser ophthalmoscopy data.

OBJECTIVES: Comparison of classification methods using data of one clinical study. The tuning of hyperparameters is assessed as part of the methods by nested-loop cross-validation. METHODS: We assess the ability of 18 statistical and machine learning classifiers to detect glaucoma. The training data set is one case-control study consisting of confocal scanning laser ophthalmoscopy measurement values from 98 glaucoma patients and 98 healthy controls. We compare bootstrap estimates of the classification error by the Wilcoxon signed rank test and box-plots of a bootstrap distribution of the estimate. RESULTS: The comparison of out-of-bag bootstrap estimators of classification errors is assessed by Spearman's rank correlation, Wilcoxon signed rank tests and box-plots of a bootstrap distribution of the estimate. The classification methods random forests 15.4%, support vector machines 15.9%, bundling 16.3% to 17.8%, and penalized discriminant analysis 16.8% show the best results. CONCLUSIONS: Using nested-loop cross-validation we account for the tuning of hyperparameters and demonstrate the assessment of different classifiers. We recommend a block design of the bootstrap simulation to allow a statistical assessment of the bootstrap estimates of the misclassification error. The results depend on the data of the clinical study and the given size of the bootstrap sample.

[Time-multiplexing stereophotography: 2D and 3D qualitative and semiquantitative evaluation of glaucomatous optic disc atrophy]. / Temps-multiplex stéréophotographie: évaluation qualitative et semi-quantitative en 2D et 3D de l'atrophie optique glaucomateuse.

PURPOSE: Real color documentation of the optic nerve head (ONH) is one of the most important methods in identifying early progression of glaucomatous optic nerve damage. This study qualitatively and semiquantitatively compared the evaluation of ONH photographs, using a 3D time-multiplexing system and conventional 2D photography, visualized on a computer monitor. PATIENTS AND METHODS: Twelve 15 degrees sequential stereophotographs from the Erlangen Glaucoma Registry were scanned by a SprintScan 35 Plus Film scanner (Polaroid, Waltham, MA, USA) and converted by computer software (3D-PIX, NuVision, McNaughton Inc., Beaverton, OR, USA) in jps format (3D). The same ONH images were shown in 2D and 3D to 22 subjects: 12 residents and ten ophthalmologists and evaluated using a standardized questionnaire. RESULTS: We observed a significantly better evaluation with stereoscopic pictures for both qualitative parameters (cup depth, visibility of the retinal nerve fibers, and the thinnest location of the neuroretinal rim) and quantitative parameters (c/d ratio and size of the disc, depending on the training level: in 3D better evaluation by the residents, in 2D by the ophthalmologists). With 2D pictures, we found better evaluation of the B zone and the stage of atrophy. Other than the method used for the entire evaluation, there was no significant difference between the groups. For the parameters weighed for clinical importance, the score of correct answers was significantly better with stereoscopic pictures. CONCLUSION: This study showed a significantly better evaluation of glaucomatous ONH atrophy with 3D images than with 2D pictures, independently of the evaluators' clinical training level. The computer-based evaluation of ONH atrophy using a time-multiplexing system (shutter glasses) may improve the diagnosis of glaucoma patients.

FISH studies on the telomeric regions of the T-cell acute lymphoblastic leukemia cell line CCRF-CEM.

So far, the problem of an influence of translocations on the telomeres of the involved chromosomes has not been addressed yet in human cells. Therefore, the telomeres of a karyotypically rather well characterized T-cell acute lymphoblastic leukemia (T-ALL) cell line (CCRF-CEM) with several marker chromosomes were examined using peptide nucleic acid (PNA) telomere FISH probes to compare the telomere length of these markers with that of the chromosome arms of their origin. In addition, chromosome libraries, centromeric probes, and subtelomeric DNA probes were used to further define the marker chromosomes. Two markers could be newly defined and a concise karyotype of the cell line could be obtained by these detailed examinations: 42-47,X,-X,del(5) (q35?),t(5;15)(q14;q13.2),t(8;9)(p11;p24),del(9)(:p13-->qter)/inv(9)(pter-->p12::q21-->p12::q21-->qter),+13,+20,+der(22)(p+ [HSR?])[cp]. The relative telomere length of all chromosomes showed considerable interchromosomal, intercellular, and inter-passage variation. However, it could be shown, that in four different passages of the examined cell line the observed differences between relative telomere lengths of the markers and the chromosomes of their origin, with two exceptions (short arms of del/inv9 and der22), were not significant. On the other hand, because of its mentioned variability, telomere length alone is not sufficient to reliably define the derivation of markers.

Does the distance to normal renal parenchyma (DTNRP) in nephron-sparing surgery for renal cell carcinoma have an effect on survival?

BACKGROUND: The effect of the distance to normal renal parenchyma (DTNRP) on survival after nephron-sparing surgery (NSS) for renal cell cancer (RCC) was analyzed. Additionally, the role of T-classification, tumor diameter and tumor grading was considered. PATIENTS AND METHODS: NSS was performed on 126 patients with RCC between 1988 and 2000. Eighty-six patients were submitted to annual follow-up. These 86 patients were sub-classified into statistical groups according to the distance to normal renal parenchyma (< or = 2mm; > 2mm - < or = 5mm; >5 mm), T-classification, tumor diameter (< or = 20mm; > 20mm - < or = 30 mm; >30 mm - < or = 50mm; > 50mm) and tumor grading. The effect of belonging to one of these groups on survival was analyzed using the Log-Rank-Test (SPSS; version 11.0) and the Kaplan and Meier survival data. The level of significance was set at p < 0.05. RESULTS: During the follow-up period, 4 patients died related to RCC and 15 patients died from other causes. The tumor-specific survival was 95.4%. At the end of 2002, the mean follow-up time was 5.5 years (range 0.1 - 14.7). None of the variables which had been analyzed in our statistical groups had an effect on the overall survival. CONCLUSION: The distance to normal renal parenchyma does not influence survival, suggesting an additional resection to be unnecessary even in cases where the DTNRP is reported by frozen section to be less than 2 mm. RCC up to 5 cn in tumor diameter can be safely removed by NSS, even in the presence of a functional intact contralateral kidney.

Automated segmentation of the optic nerve head for diagnosis of glaucoma.

Glaucoma is the second most common cause of blindness worldwide. Low awareness and high costs connected to glaucoma are reasons to improve methods of screening and therapy. A well-established method for diagnosis of glaucoma is the examination of the optic nerve head using scanning-laser-tomography. This system acquires and analyzes the surface topography of the optic nerve head. The analysis that leads to a diagnosis of the disease depends on prior manual outlining of the optic nerve head by an experienced ophthalmologist. Our contribution presents a method for optic nerve head segmentation and its validation. The method is based on morphological operations, Hough transform, and an anchored active contour model. The results were validated by comparing the performance of different classifiers on data from a case-control study with contours of the optic nerve head manually outlined by an experienced ophthalmologist. We achieved the following results with respect to glaucoma diagnosis: linear discriminant analysis with 27.7% estimated error rate for automated segmentation (aut) and 26.8% estimated error rate for manual segmentation (man), classification trees with 25.2% (aut) and 22.0% (man) and bootstrap aggregation with 22.2% (aut) and 13.4% (man). It could thus be shown that our approach is suitable for automated diagnosis and screening of glaucoma.

Simulation based analysis of automated, classification of medical images.

OBJECTIVES: The ability of various classifiers to discriminate between normal and glaucomatous eyes based on features derived from automated analysis of laser scanning images of the eye background is investigated. METHODS: To compare the classifiers without over-optimization for a given dataset, we use a simulation model to create topography images. We designed three different simulation setups as model of extreme situations and medical subgroups. RESULTS: Neither linear nor tree-based classifiers are ideal for all setups. The most robust performance is obtained by a combination of both, so-called Double-Bagging. Classification of real data from a case-control study shows best results with Double-Bagging. All results obtained with the analysis method extracting features automatically are worse than those obtained by the same classifiers but with features derived from an analysis method that requires intervention of a physician. CONCLUSIONS: Robust classification results for classification of laser scanning images obtained with the Heidelberg Retina Tomograph are achieved by combined classifiers. The examined automated procedure causes an increased misclassification error compared to the established clinical routine requiring an expert physician's intervention.

Comparison of tree-based methods for prognostic stratification of survival data.

Tree-based methods can be used to generate rules for prognostic classification of patients that are expressed as logical combinations of covariate values. Several splitting algorithms have been proposed for generating trees from survival data. However, the choice of an appropriate algorithm is difficult and may also depend on clinical considerations. By means of a prognostic study of patients with gallbladder stones and of a simulation study, we compare the following splitting algorithms: log-rank statistic adjusted for measurement scale with (AP) and without (AU) pruning, exponential log-likelihood loss (EP), Kaplan-Meier (KP) distance of survival curves, unadjusted log-rank statistic (LP), martingale residuals (MP), and node impurity (ZP). With the exception of the AU algorithm (based on a Bonferroni-adjusted p-value driven stopping rule), trees are pruned using the measure of split-complexity, and optimally-sized trees are selected using cross-validation. The integrated Brier score is used for the evaluation of predictive models. According to the results of our simulation study and of the clinical example, we conclude that the AU, AP, EP, and LP algorithm may yield superior predictive accuracy. The choice among these four algorithms may be based on the required parsimonity and on medical considerations.

Diagnosis of glaucoma by indirect classifiers.

OBJECTIVES: Demonstration of the applicability of a framework called indirect classification to the example of glaucoma classification. Indirect classification combines medical a priori knowledge and statistical classification methods. The method is compared to direct classification approaches with respect to the estimated misclassification error. METHODS: Indirect classification is applied using classification trees and the diagnosis of glaucoma. Misclassification errors are reduced by bootstrap aggregation. As direct classification methods linear discriminant analysis, classification trees and bootstrap aggregated classification trees are utilized in the problem of glaucoma diagnosis. Misclassification rates are estimated via 10-fold cross-validation. RESULTS: Indirect classification techniques reduce the misclassification error in the context of glaucoma classification compared to direct classification methods. CONCLUSIONS: Embedding a priori knowledge into statistical classification techniques can improve misclassification results. Indirect classification offers a framework to realize this combination.

Homocysteine and risk of open-angle glaucoma.

Homocysteine levels and the frequency of heterozygous methylenetetrahydrofolate reductase (MTHFR) C677T mutation are increased in open-angle glaucoma. Since homocysteine can induce vascular injury, alterations in extracellular matrix remodelling, and neuronal cell death, these findings may have important implications for understanding glaucomatous optic neuropathy.