Computed Tomography Radiomics to Differentiate Intrahepatic Cholangiocarcinoma and Hepatocellular Carcinoma

AIMS

Intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC) differ in prognosis and treatment. We aimed to non-invasively differentiate iCCA and HCC by means of radiomics extracted from contrast-enhanced standard-of-care computed tomography (CT).

MATERIALS AND METHODS

In total, 94 patients (male, n = 68, mean age 63.3 ± 12.4 years) with histologically confirmed iCCA (n = 47) or HCC (n = 47) who underwent contrast-enhanced abdominal CT between August 2014 and November 2021 were retrospectively included. The enhancing tumour border was manually segmented in a clinically feasible way by defining three three-dimensional volumes of interest per tumour. Radiomics features were extracted. Intraclass correlation analysis and Pearson metrics were used to stratify robust and non-redundant features with further feature reduction by LASSO (least absolute shrinkage and selection operator). Independent training and testing datasets were used to build four different machine learning models. Performance metrics and feature importance values were computed to increase the models' interpretability.

RESULTS

The patient population was split into 65 patients for training (iCCA, n = 32) and 29 patients for testing (iCCA, n = 15). A final combined feature set of three radiomics features and the clinical features age and sex revealed a top test model performance of receiver operating characteristic (ROC) area under the curve (AUC) = 0.82 (95% confidence interval =0.66-0.98; train ROC AUC = 0.82) using a logistic regression classifier. The model was well calibrated, and the Youden J Index suggested an optimal cut-off of 0.501 to discriminate between iCCA and HCC with a sensitivity of 0.733 and a specificity of 0.857.

CONCLUSIONS

Radiomics-based imaging biomarkers can potentially help to non-invasively discriminate between iCCA and HCC.

Surgeon and surgical conference attendee views on live surgery events

Based on the principles of biomedical ethics, the authors conducted a survey focusing on the ethical aspects of, didactic benefits of and possible alternatives to live surgery events. This work provides an investigation of the ethics of live surgery events in an interdisciplinary and multicentre setting. Critical ethical concerns regarding the justification of such events are highlighted through evaluation of attendees and surgeons.

Computer-assisted femoral head reduction osteotomies: an approach for anatomic reconstruction of severely deformed Legg-Calvé-Perthes hips. A pilot study of six patients

BACKGROUND

Legg-Calvé-Perthes (LCP) is a common orthopedic childhood disease that causes a deformity of the femoral head and to an adaptive deformity of the acetabulum. The altered joint biomechanics can result in early joint degeneration that requires total hip arthroplasty. In 2002, Ganz et al. introduced the femoral head reduction osteotomy (FHRO) as a direct joint-preserving treatment. The procedure remains one of the most challenging in hip surgery. Computer-based 3D preoperative planning and patient-specific navigation instruments have been successfully used to reduce technical complexity in other anatomies. The purpose of this study was to report the first results in the treatment of 6 patients to investigate whether our approach is feasible and safe.

METHODS

In this retrospective pilot study, 6 LCP patients were treated with FHRO in multiple centers between May 2017 and June 2019. Based on patient-specific 3D-models of the hips, the surgeries were simulated in a step-wise fashion. Patient-specific instruments tailored for FHRO were designed, 3D-printed and used in the surgeries for navigating the osteotomies. The results were assessed radiographically [diameter index, sphericity index, Stulberg classification, extrusion index, LCE-, Tönnis-, CCD-angle and Shenton line] and the time and costs were recorded. Radiologic values were tested for normal distribution using the Shapiro-Wilk test and for significance using Wilcoxon signed-rank test.

RESULTS

The sphericity index improved postoperatively by 20% (p = 0.028). The postoperative diameter of the femoral head differed by only 1.8% (p = 0.043) from the contralateral side and Stulberg grading improved from poor coxarthrosis outcome to good outcome (p = 0.026). All patients underwent acetabular reorientation by periacetabular osteotomy. The average time (in minutes) for preliminary analysis, computer simulation and patient-specific instrument design was 63 (±48), 156 (±64) and 105 (±68.5), respectively.

CONCLUSION

The clinical feasibility of our approach to FHRO has been demonstrated. The results showed significant improvement compared to the preoperative situation. All operations were performed by experienced surgeons; nevertheless, three complications occurred, showing that FHRO remains one of the most complex hip surgeries even with computer assistance. However, none of the complications were directly related to the simulation or the navigation technique.

Spatially controlled VLS epitaxy of gallium arsenide nanowires on gallium nitride layers

MOVPE of Au catalyzed p-GaAs nanowires on n-GaN layers. Left: VLS growth optimization (density and morphology). Middle and right: site-controlled pn-junctions by lateral and vertical anisotropic NWs in structured SiOx openings (scalebar 1 μm).

Stability and spectral properties of the dication Ne2+2

Two different types of metastable states in Ne2+2 are predicted and possible decay transitions as well as the ensuing lifetimes and intensity distributions are studied.

{Tc(NO)(Cp)(PPh3)}+– a novel technetium(i) core

Access to pseudotetrahedral [Tc(NO)(Cp)(PPh₃)X]^0,+complexes (X = halide, Ph, CO) has been found by a convenient procedure starting from [Tc(NO)Y₂(PPh₃)₂(MeCN)] (Y = Cl, Br) and subsequent ligand exchange reactions.

Word Design for Biomolecular Information Processing

The design of DNA sequences plays a fundamental role for many biomolecular applications and is one of the most important theoretical tasks to fathom the potential of molecular information processing. Optimization strategies have been based on the model of stiff “digital” polymers by counting the number of base mismatches (Hamming distance and related distances). In this work we show the limitation of such a combinatorial approach because of the ability of DNA to build more complex structures. We develop a model platform to optimize word sets according to all possible secondary structures occurring for the relevant word-word interactions. The fidelity of the hybridization reactions can be improved significantly and as an example of a set of 24 words of 16-mers we show that the optimal set has unique physical properties, such as binding energy, melting temperature, and G+C content.

Reduction techniques for network validation in systems biology

The rapidly increasing amount of experimental biological data enables the development of large and complex, often genome-scale models of molecular systems. The simulation and analysis of these computer models of metabolism, signal transduction, and gene regulation are standard applications in systems biology, but size and complexity of the networks limit the feasibility of many methods. Reduction of networks provides a hierarchical view of complex networks and gives insight knowledge into their coarse-grained structural properties. Although network reduction has been extensively studied in computer science, adaptation and exploration of these concepts are still lacking for the analysis of biochemical reaction systems. Using the Petri net formalism, we describe two local network structures, common transition pairs and minimal transition invariants. We apply these two structural elements for network reduction. The reduction preserves the CTI-property (covered by transition invariants), which is an important feature for completeness of biological models. We demonstrate this concept for a selection of metabolic networks including a benchmark network of Saccharomyces cerevisiae whose straightforward treatment is not yet feasible even on modern supercomputers.

Current Controlled Photoelectrochemical Etching of Gan Leaving Smooth Surfaces

We have etched GaN grown by plasma source MBE in aqueous solutions of KOH in an electrochemical cell under HeCd laser illumination and additional current control.The etch rate was dramatically enhanced up to 8 μm/h by an applied current density of 6.4 mAcm-2. Photocurrent control leads to etched GaN surfaces exhibiting mirror-like appearance with uniform interference color. According to mechanical profilometry, they have a roughness of less than 3.5 nm after etching of several hundred nanometers, which is comparable to the roughness prior to etching. This etching process allows in situ control via photocurrent and induced yellow luminescence.

Low Dose Thalidomide in Patients with Relapsed or Refractory Multiple Myeloma

Remarkable results of the treatment of refractory multiple myeloma with thalidomide have been reported. In most preceding studies, the given thalidomide dose was escalated to a maximum tolerated dose of up to 800 mg/d. The frequency of adverse effects correlates with dose intensity. Since a significant gain of therapeutic effects could not be observed as thalidomide dosage was escalated, the optimal dose of thalidomide remains to be determined. We report the results of a study with low dose thalidomide (median administered dose 100 mg/d, range 50-400 mg/d). Twenty-four relapsed (n = 19) or resistant (n = 5) multiple myeloma patients were included in the study. Twelve patients (50%) received thalidomide as monotherapy, 8 patients (33%) received a combination of thalidomide and dexamethasone (every 4 weeks 40 mg/day for 4 days) and 4 patients (17%) who were resistant to vincristine, doxorubicin, dexamethasone (VAD) received VAD combined with thalidomide. Overall, a response was observed in 12 patients (50%). Of the 12 patients treated with low dose thalidomide alone 5 (42%) responded, of the 8 patients who received a combination of thalidomide and dexamethasone 5 (63%) responded and of the 4 patients who had thalidomide in addition to VAD 2 patients (50%) responded. In 3 patients, thalidomide treatment had to be discontinued because of side effects and 1 patient died before response could be assessed. We conclude that low dose thalidomide is an effective and safe rescue therapy in relapsing or refractory multiple myeloma. Response to thalidomide might be dependent on prognostic parameters and tumor burden. To answer these questions larger prospective studies are necessary.

Cytogenetic patterns in multiple myeloma after a phase of preceding MGUS

BACKGROUND

Presenting the same histological diagnosis, multiple myeloma (MM) shows a large genomic variety, resulting in variable times of overall survival.

MATERIALS AND METHODS

To investigate major cytogenetic categories (any 14q-translocation, t(11;14), t(4;14), 13q-deletions, 17p-deletions) and their clinical consequences in MM after a pre-existing monoclonal gammopathy (MM post-MGUS), we performed a comparative analysis of 41 patients with MM post-MGUS and 287 patients with unknown prior history MM (U-MM).

RESULTS

In MM post-MGUS, a t(11;14) was found to be more frequent than in U-MM (24% vs. 14%) and it was associated with significantly shortened survival (24 months vs. 70 months in U-MM; P = 0.01). MM post-MGUS was further characterized by a higher frequency of 13q-deletions only (absence of all other specific abnormalities; 28% vs. 12% in U-MM; P = 0.02). A 13q-deletion only was an indicator of long survival in MM post-MGUS (median not yet reached) as opposed to U-MM (median survival, 29 months; P = 0.001). 17p-deletions were infrequent in MM post-MGUS (3% vs. 16% in U-MM; P = 0.04). Survival times for patients with t(4;14) and/or 17p-deletions and other abnormalities were similar in both MM patient cohorts.

CONCLUSIONS

Our data suggest that t(11;14) and 13q-deletions have distinct prognostic implications in the context of MM post-MGUS.

Chromosomal abnormalities of young multiple myeloma patients (<45 yr) are not different from those of other age groups and are independent of stage according to the International Staging System

Little is known about tumor-related prognostic factors, in particular specific chromosomal abnormalities, in young patients with multiple myeloma (MM). We therefore investigated the chromosomal pattern by interphase fluorescence in situ hybridization (chromosomes 13q14, 14q32-translocations, chromosomes associated with hyperdiploidy) in 38 young patients with MM (age <45 yr) and compared the results with those observed in 69 patients with intermediate age (45-70 yr) and 64 elderly patients (age >70 yr). All chromosomal patterns were not significantly different between the three age cohorts. Similarly, standard MM parameters were equally distributed between these MM patient populations. However, survival by the International Staging System (ISS) for MM revealed marked differences between stage I/II (median survival not yet reached) and stage III (23.4 months; P < 0.0003) among young MM patients. A significant survival difference between ISS-stage I/II and ISS-stage III patients was also noted in the intermediate age group (median 65.4 months vs. 24.6 months; P = 0.0009). However, this difference disappeared among elderly MM patients (39.6 months in ISS-stage I/II vs. 32 months in ISS-stage III patients; P = 0.94), but it was unrelated to the cytogenetic pattern. Our results indicate that MM in young patients does not represent a distinct biologic entity, and that short survival of younger MM patients at ISS-stage III is independent of the molecular cytogenetic pattern.

Bortezomib in relapsed multiple myeloma: response rates and duration of response are independent of a chromosome 13q-deletion

Studies of bortezomib in patients with relapsed multiple myeloma (MM) suggested that bortezomib may be active even in the presence of adverse prognostic factors. We therefore evaluated 62 patients with relapsed/refractory MM who were treated with single-agent bortezomib, and addressed the question whether or not the negative prognostic impact of unfavorable cytogenetic abnormalities may be overcome by bortezomib. By interphase fluorescence in situ hybridization (FISH), a deletion of chromosome 13q14 [del(13q14)] was present in 33 patients (53%). Overall response rates to bortezomib were similar in patients with and without del(13q14) (45 versus 55%; P=0.66), and rates of complete remission (CR) near CR were also not different between the two patient populations (18 versus 14%). Three patients had a t(4;14)(p16;q32) in addition to del(13q14), and all of them had a >50% paraprotein reduction. Median duration of response was 12.3 months in patients with del(13q14) compared with 9.3 months in patients with normal 13q-status (P=0.25), and survival was also not different between the two patient populations. Patients not benefiting from single-agent bortezomib were characterized by the combined presence of a del(13q14) and low serum albumin (median survival 4.6 months). Our results provide evidence for remarkable activity of bortezomib in MM with del(13q14). Patients who do not respond to bortezomib and consecutively have short time to treatment failure and overall survival can be identified by low serum albumin in addition to del(13q14) and should be considered for bortezomib combinations.

Both IGH translocations and chromosome 13q deletions are early events in monoclonal gammopathy of undetermined significance and do not evolve during transition to multiple myeloma

Molecular and genetic events associated with the transition from monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM) are still poorly characterized. We investigated serial bone marrow specimens from 11 patients with MGUS who eventually progressed to MM (MM post-MGUS) by interphase fluorescence in situ hybridization for immunoglobulin heavy-chain gene (IgH) translocations and chromosome 13q deletions (del(13q)). In nine patients, IgH translocations were present both in MGUS and MM post-MGUS plasma cells, including three t(11;14)(q13;q32) and one t(4;14)(p16;q32), which was observed already 92 months prior to MM. Similarly, all five MM patients with del(13q) had this aberration already at the MGUS stage. Two patients without IgH translocation and del(13q) had chromosomal gains suggesting hyperdiploidy, but IgH translocations and/or del(13q) did not emerge at MM post-MGUS. IgH translocations and del(13q) are early genetic events in monoclonal gammopathies, suggesting that additional events are required for the transition from stable MGUS to progressive MM.

Diffuse large B-cell lymphomas with plasmablastic/plasmacytoid features are associated with TP53 deletions and poor clinical outcome

To define reproducible criteria for subgroups of diffuse large B-cell lymphomas (DLBCL), including lymphomas with plasmablastic/plasmacytoid features (PB/PC-Fs), we investigated 66 DLBCL; the samples were categorized as either centroblastic (CB), immunoblastic (IB) or PB/PC-F applying standardized morphologic criteria. Blinded specimens were reviewed by three independent pathologists. The final consensus classification included 44 CB (67%), seven IB (10%) and 15 PB/PC-F (23%). The interobserver agreement between two centers (Vienna, Würzburg) was 93.5%. Most PB/PC-F were CD20+, cIgM+, MUM-1+, CD138+/-, bcl-6-, corresponding to an activated B-cell phenotype. Immunoglobulin-V(H) gene mutation analysis was consistent with a germinal or postgerminal center-cell origin. By fluorescence in situ hybridization analysis, 11/13 (85%) PB/PC-F had a monoallelic TP53 deletion. The pretreatment characteristics of patients with PB/PC-F included a tendency for more B symptoms, extranodal disease and a higher IPI. Importantly, PB/PC-F were resistant to standard chemotherapy (complete remission rate 47%, relapse rate 71%) and even autologous stem-cell transplantation. The median overall survival (OS) (14 months, P<0.002) and disease-free survival (6 months, P=0.02) were significantly shorter compared to patients with CB and IB. The OS difference was pronounced within the low and low-intermediate IPI risk group (P<0.001). Our data indicate a strong association of plasmablastic/plasmacytoid morphology with TP53 deletions, poor response to chemotherapy and short survival.

Single hemicerclage for lateral type B malleolar fracture--a novel, minimal and reliable osteosynthesis

AIM OF STUDY

To investigate the short- and long-term outcome of patients with isolated lateral malleolar fracture type B treated with a single hemicerclage out of metallic wire or PDS cord.

METHODS

Over an 8-year period 97 patients were treated with a single hemicerclage for lateral malleolar fracture type B and 89 were amenable to a follow-up after mean 39 months, including interview, clinical examination and X-ray controls.

RESULTS

The median operation time was 35 minutes (range 15-85 min). X-ray controls within the first two postoperative days revealed an anatomical restoration of the upper ankle joint in all but one patient. The complication rate was 8%: hematoma (2 patients), wound infection (2), Sudeck's dystrophy (2) and deep vein thrombosis (1). Full weight-bearing was tolerated at median 6.0 weeks (range 2-26 weeks). No secondary displacement, delayed union or consecutive arthrosis of the upper ankle joint was observed. All but one patient had restored symmetric joint mobility. Ninety-seven percent of patients were satisfied or very satisfied with the outcome. Following bone healing, hemicerclage removal was necessary in 19% of osteosyntheses with metallic wire and in none with PDS cord.

CONCLUSION

The single hemicerclage is a novel, simple and reliable osteosynthesis technique for isolated lateral type B malleolar fractures and may be considered as an alternative to the osteosynthesis procedures currently in use.

Beneficial effect of high-dose chemotherapy in multiple myeloma patients with unfavorable prognostic features

It has been established that high-dose chemotherapy (HDT) improves the therapeutic outcome of patients with multiple myeloma (MM) as compared with standard-dose therapy (SDT); however, little is known about the impact of HDT on different prognostic groups of MM patients. We therefore compared the survival times of 77 patients with previously untreated MM who were enrolled in HDT regimens with those of 64 similar patients <65 years old, who would be eligible for HDT but were treated by SDT. Overall, HDT was superior to SDT with respect to achievement of complete remissions (28% versus 2%; P <0.0001) and improvement of progression-free survival (PFS) (30.2 versus 21.2 months; P = 0.01) as well as overall survival (OS) (median 54.9 versus 49.4 months; P = 0.048). According to the chromosome 13q14 status as determined by fluorescence in situ hybridization and serum levels of beta(2)-microglobulin (beta(2)M), MM patients were separated into a standard-risk group (normal chromosome 13q14 and beta(2)M </=4 mg/l) and a high-risk group (deletion of chromosome 13q14 and/or beta(2)M >4 mg/l). Among patients of the high-risk group, both PFS (26.4 versus 10.7 months; P = 0.004) and OS times (40 versus 23 months; P = 0.05) were longer in patients receiving HDT compared with patients treated by SDT. In the standard-risk group, PFS and OS times were not significantly different between HDT patients and SDT patients. Results of this retrospective analysis suggest that the beneficial effects of HDT are greater in MM patients with high-risk features than in patients with absence of such poor prognostic indicators.

Pattern selection in a cooperative biochemical in vitro amplification system: the role of parasites

Previously, numerical simulations have shown that evolving systems can be stabilized against emerging parasites by pattern formation in spatially extended flow reactors. Hence, it can be argued that pattern formation is a prerequisite for any experimental investigation of the biochemical evolution of cooperative function. Here, we study a model of an experimental biochemical system for the cooperative in vitro amplification of DNA strands and show that emerging parasites can induce a complex pattern formation even when no pattern formation occurs without parasites. In an adiabatic approximation where the cooperative amplification reaction is assumed to adapt fast to slowly emerging parasites, the parasite concentration itself acts as a Steuer parameter for the selection of various complex patterns. Without such an adiabatic approximation only transient patterns emerge. As any species can grow for very low concentrations, the parasite is able to infect the entire reactor and the system is finally diluted out. In the experimental biochemical system, however, the species are individual molecules and the growth of spatially separated, non-infected regions becomes feasible. Hence a cutoff threshold for the minimal concentration is applied. In these simulations the otherwise lethal infection by parasites induces the formation of spatiotemporal spirals, and this spatial structure help the host and parasitoid species to survive together. These theoretical results describe an inherent property of cooperative reactions and have an important impact on experimental investigations on the molecular evolution and complex function in spatially extended reactors. Since the formation of the complex pattern is restricted either to a rather large cutoff value or a special choice of the kinetic parameters, we, however, conclude that the persistence of evolving cooperative amplification is not possible in a simple reaction-diffusion reactor. Experimental set-ups with patchy environments, e.g. biomolecular amplification in coupled microstructured flow chambers or in microemulsion, are eligible candidates for the observation of such a self-organized pattern selection.

Advances in the biology and therapeutic management of multiple myeloma

During the past decade, new developments have increased our understanding of the biological features of multiple myeloma (MM), and novel therapeutic approaches have improved the outcome and quality of life. The importance of both the malignant clone and the bone marrow environment for disease evolution and propagation has been recognized, and therapeutic approaches that target both components of the disease process appear to be most promising. Along this line, thalidomide has been observed to exert activity in chemotherapy-refractory MM and thus expands the therapeutic armamentarium against MM. Use of high-dose melphalan with autologous stem cell transplantation has resulted in an improved rate of complete remissions as well as prolonged event-free and overall survival. Novel treatment strategies exploiting anti-myeloma immunity (nonmyeloablative allogeneic transplantation, vaccination) are being investigated and carry the potential to further improve the outcome of patients with MM.

Absence of clonal chromosomal relationship between concomitant B-CLL and multiple myeloma--a report on two cases

B-cell chronic lymphocytic leukemia (B-CLL) and multiple myeloma (MM) are chronic B-cell malignancies that represent different stages of B-cell maturation. Occasionally, both diseases are present in the same patient, and this raises the question of clonal associations between the two neoplasms. We here report on two patients with concomitant B-CLL and MM. Clonal chromosomal abnormalities in both lymphocytic cells and plasma cells were studied by interphase fluorescence in situ hybridization (FISH) using a panel of 24 chromosome- and region-specific DNA probes. In the first patient, cytogenetics revealed 47, X, t(Y;22)(p11;q10), +12, dell4(q21q32). By FISH, +12 was present in lymphoid cells, but not in plasma cells. MM cells were characterized by multiple chromosomal gains (1, 11q23) and losses (5q, 10, 13q14, 15, 17p13, Y), which were all undetectable in lymphoid cells. The second patient, in whom no clonal abnormalities were obtained by conventional cytogenetic analysis, had lymphoid cells with loss of 8q24 by FISH. In contrast, evidence for a gain of 8q24 (consistent with amplification of c-myc) was obtained in 13% of plasma cells. Plasma cells were further characterized by gains of chromosomes 1, 3, 11, 18, and Y. We thus conclude that this comprehensive molecular cytogenetic analysis demonstrates the existence of two clonally distinct B-cell malignancies in both patients.

Deletion of chromosome 13q14 detected by fluorescence in situ hybridization has prognostic impact on survival after high-dose therapy in patients with multiple myeloma

Interphase cytogenetic analysis of chromosome 13q14 was performed in 28 patients with multiple myeloma (MM) receiving high-dose therapy followed by autologous (n=24) or allogeneic (n=4) stem cell support. Eleven (39%) patients were found to have a deletion of chromosome 13q14. Response rates to high-dose therapy were independent of the chromosome 13 status, but patients with a deletion of 13q14 had a significantly shorter progression-free (p=0.001) and overall survival (p=0.012) than patients with normal chromosome 13q14. Our results indicate that high-dose therapy appears promising in patients with normal chromosome 13, whereas in patients with a deletion of 13q14 innovative therapeutic concepts are warranted.

Deletions of chromosome 13q in monoclonal gammopathy of undetermined significance

Since deletion of chromosome 13q is a clinically relevant feature in multiple myeloma (MM), we analyzed bone marrow plasma cells from 29 patients with monoclonal gammopathy of undetermined significance (MGUS) to investigate the chromosome 13 status in MGUS. Studies were performed by interphase fluorescence in situ hybridization (FISH) with a panel of 13q14-specific probes (RB1, D13S319, D13S25, D13S31). Plasma cells with a deletion of at least one of the 13q14 loci were detected in 13 patients (44.8%) with MGUS. In five patients (17.2%), deletions of all four 13q14-specific probes were observed, and the additional deletion of a 13q telomeric region (D13S327) suggested loss of the entire 13q arm or monosomy 13. Loss of 13q14 was observed to be monoallelic and to occur in 11.0 to 35.0% of plasma cells (cut-off levels for a deletion <10% with all probes). Nine of 17 patients (52.9%) with MM progressing from a pre-existing MGUS had evidence for a deletion of 13q14 as determined by FISH with the RB1 probe. These results suggest that deletion of 13q14 is an early event in the development of monoclonal gammopathies, but its role for the eventual progression to MM remains to be determined prospectively.

Multiple myeloma with deletion of chromosome 13q is characterized by increased bone marrow neovascularization

Anti-angiogenesis therapy with thalidomide has been reported to have marked activity in multiple myeloma (MM). As cytogenetics is an independent prognostic factor in MM, we analysed bone marrow (BM) angiogenesis and cytogenetic abnormalities in 34 patients with active MM. BM microvessel density (MVD), as determined by staining with anti-CD34, was significantly higher in MM (MVD: 221 +/- 94 per mm2) than in controls (80 +/- 36; P < 0.0001). In patients with the presence of at least one unfavourable cytogenetic abnormality (deletion of 13q14, deletion of 17p13, aberrations of 11q), a significantly increased BM MVD was observed (254 +/- 93 vs. 160 +/- 60 in patients with absence of these abnormalities; P = 0.0035). Further analyses indicated that increased BM MVD was significantly correlated with deletion of 13q14 (259 +/- 96 vs. 188 +/- 80; P = 0. 026), but not with other cytogenetic, clinical and laboratory MM parameters. We conclude that BM neovascularization is particularly high in MM with deletion of 13q14, which provides a rationale for use of anti-angiogenic strategies in the treatment of MM with high-risk cytogenetics.

The biology of multiple myeloma

Multiple myeloma (MM) is a B-cell malignancy originating from pre-switched, follicle center B-lymphocytes which differentiate to plasma cells accumulating in the bone marrow. MM cells are characterized by a profound genetic instability resulting in a complex set of numerical and structural chromosomal abnormalities. Among these abnormalities, translocations involving 14q32, the immunoglobulin heavy-chain locus, are the most frequent aberrations, but translocation partners are remarkably heterogeneous. Chromosome 13q14 may harbor a critical tumor suppressor gene since MM patients with deletion of 13q14 experience short overall survival after conventional-dose and high-dose chemotherapy. Bone marrow stroma cells support growth and survival of MM cells, which in turn influence the bone marrow microenvironment. This is particularly evident by the markedly increased bone marrow vascularization observed in most patients with active MM.

Aneuploidy of chromosome 7 can be detected in invasive lung cancer and associated premalignant lesions of the lung by fluorescence in situ hybridisation

In the present study the chromosomal status of seven invasive non small cell lung cancer specimens and associated premalignant lesions was investigated. By fluorescence in situ hybridisation (FISH) with centromere specific probes, an increase in the percentage of aneuploid cells from pre-invasive to invasive lesions could be demonstrated (mean 8.5 and 59%, respectively, for chromosome 7). Furthermore, mean chromosome copy numbers were higher in invasive carcinomas as compared to premalignant lesions, indicating polyploidization during tumor development. Increasing evidence suggests that aberrations of chromosome 7 occur early in the development of lung cancer. Whether these aberrations can be used as a biomarker for future neoplastic progression remains to be determined.

Deletion of 13q14 remains an independent adverse prognostic variable in multiple myeloma despite its frequent detection by interphase fluorescence in situ hybridization

Interphase fluorescence in situ hybridization (FISH) studies of chromosomal region 13q14 were performed to investigate the incidence and clinical importance of deletions in multiple myeloma (MM). Monoallelic deletions of the retinoblastoma-1 (rb-1) gene and the D13S319 locus were observed in 48 of 104 patients (46.2%) and in 28 of 72 (38.9%) patients, respectively, with newly diagnosed MM. FISH studies found that 13q14 was deleted in all 17 patients with karyotypic evidence of monosomy 13 or deletion of 13q but also in 9 of 19 patients with apparently normal karyotypes. Patients with a 13q14 deletion were more likely to have stage III disease (P =.022), higher serum levels of beta(2)-microglobulin (P =.059), and a higher percentage of bone marrow plasma cells (P =.085) than patients with a normal 13q14 status on FISH analysis. In patients with a deletion of 13q14, myeloma cell proliferation (Ki-67) was markedly increased (22.0% +/- 6.9% compared with 15.6% +/- 8.2% in patients without the deletion; P =.0008). Evaluation of bromodeoxyuridine incorporation in 5 patients revealed that both rb-1-deleted and rb-1-normal MM subpopulations were proliferative. The presence of a 13q14 deletion on FISH analysis was associated with a significantly lower rate of response to conventional-dose chemotherapy (40.8% compared with 78. 6%; P =.009) and a shorter overall survival (24.2 months compared with > 60 months; P <.005) than in patients without the deletion. Multivariate analysis of prognostic factors confirmed the independent predictive value of 13q14 deletions for shortened survival. In conclusion, deletions of 13q14 are frequently detected by interphase FISH in patients with newly diagnosed MM, correlate with increased proliferative activity, and represent an independent adverse prognostic feature in MM. (Blood. 2000;95:1925-1930)

Predictive role of interphase cytogenetics for survival of patients with multiple myeloma

PURPOSE

Recent metaphase cytogenetic studies suggested that specific chromosomal abnormalities are of prognostic significance in patients with multiple myeloma (MM). Because the true incidence of chromosomal abnormalities in MM is much higher than that detected by metaphase analysis, we used interphase fluorescence in situ hybridization (FISH) to determine the prognostic value of specific chromosomal aberrations.

PATIENTS AND METHODS

Bone marrow plasma cells from 89 previously untreated patients with MM were studied consecutively by FISH to detect the deletions of 13q14, 17p13, and 11q and the presence of t(11;14)(q13;q32). FISH results were analyzed in the context of clinical parameters (response to treatment and survival after conventional-dose chemotherapy), and a multivariate analysis of prognostic factors was performed.

RESULTS

By FISH, the deletion of 13q14 occurred in 40 patients (44.9%), deletion of 17p13 in 22 (24.7%), and 11q abnormalities in 14 (15.7%; seven with t(11;14)). Deletions of 13q14 and 17p13 were associated with poor response to induction treatment (46.9% v 77.3% in those without deletions, P =.006 and 40.0% v 73.2%, P =.008, respectively) and short median overall survival (OS) time (24.2 v 88.1 months, P =. 008 and 16.2 v 51.3 months, P =.008, respectively). Short median OS time was also observed for patients with 11q abnormalities (13.1 v 41.6 months, P =.02). According to the number of unfavorable cytogenetic features (deletion of 13q14, deletion of 17p13, and aberrations of 11q) that were present in each patient (0 v 1 v 2 or 3), patients with significantly different OS times could be discriminated from one another (102.4 v 29.6 v 13.9 months, P <.001, respectively).

CONCLUSION

For patients with MM who were treated with conventional-dose chemotherapy, interphase FISH for 13q14, 17p13, and 11q provides prognostically relevant information in addition to that provided by standard prognostic factors. This observation may be considered for risk-adapted stratifications of MM patients in future clinical trials.

Analytical solution of the two-frequency lidar inversion technique

A two-frequency lidar inversion on the assumptions of a range-independent relationship between the extinction coefficients of the two considered lidar wavelengths and of constant extinction-to-backscatter ratios was originally developed by Potter [Appl. Opt. 26, 1250 (1987)]. It is an iterative procedure to retrieve the boundary value for solution of the single-scatter lidar equation. This boundary value is expressed by the aerosol transmission along the evaluated lidar path. Recently, Kunz [Appl. Opt. 38, 1015 (1999)] stated that there is not enough information in the lidar signals of two wavelengths to obtain a unique solution for the boundary value and hence for the aerosol extinction profile. It is shown that a unique solution of the two-frequency lidar inversion exists, for which an analytical expression of the boundary value and, hence, the aerosol extinction profile, is given.

Trisomy 13 is associated with poor prognosis in idiopathic myelofibrosis with myeloid metaplasia

We report a case of idiopathic myelofibrosis with trisomy 13 as the sole clonal aberration, as demonstrated by metaphase cytogenetics. The clinical course was especially poor in this case, with death in blast crisis occurring within two weeks from diagnosis. The dismal outcome bears striking similarity to two previous cases of idiopathic myelofibrosis and trisomy 13 reported in the literature. Therefore trisomy 13 may be a predictor of a rapidly fatal outcome in this otherwise indolent disease. Fluorescence in situ hybridisation (FISH) with a chromosome 13 specific probe may enhance the detection of this aberration, since only 50% of cases of idiopathic myelofibrosis are karyotyped successfully using conventional techniques.

Expression of the lung resistance protein predicts poor outcome in patients with multiple myeloma

Expression of the lung resistance protein (LRP) is associated with resistance to various anticancer drugs including melphalan and, therefore, may affect the clinical outcome in multiple myeloma (MM). To determine the clinical significance of LRP, we have compared LRP expression in bone marrow plasma cells with clinical parameters including response to chemotherapy and survival of previously untreated patients with MM (n = 72). LRP expression immunocytochemically assessed by means of the LRP-56 monoclonal antibody was positive (> or =10% staining plasma cells) in 44 (61%) samples. There was no correlation between LRP expression and age, sex, type of the paraprotein, serum creatinine, stage, beta2-microglobulin, serum lactate dehydrogenase, or C-reactive protein. However, LRP expression was more frequently observed in patients with a p53 deletion than in those without such a deletion (P = 0.01). The overall response rate for all of the patients evaluable for response to induction chemotherapy (n = 58) was 67%. The response rate was 87% for patients without LRP expression but only 54% for patients with LRP expression (P = 0.01). Kaplan-Meier analysis revealed that patients with LRP expression had a shorter overall survival (median, 33 months) than those without LRP expression (median not reached; P = 0.04). These data show that LRP expression is an important marker for clinical drug resistance and predicts a poor outcome in MM.

Significance of multiple scattering from tropospheric aerosols for ground-based backscatter lidar measurements

The influence of multiple scattering on the retrieval of extinction coefficients of tropospheric aerosols from ground-based backscatter lidar measurements is numerically modeled. In a first step, lidar returns are computed by means of a Monte Carlo code for model atmospheres with different aerosol types and different extinction coefficient profiles. In so doing, synthetic lidar signals with and without multiple scattering can be simulated. In a second step, both types of signal are inverted by the most frequently used analytical solution, which, however, is based on the single-scatter assumption. From a comparison of the results, the error of the retrieved aerosol-extinction profiles can be quantitatively determined. It was found that the contribution of multiply scattered photons to the lidar signals is typically below 10% and never exceeds 20%. The relative errors of the retrieved aerosol-extinction profile in the planetary boundary layer are still smaller; they were determined to be less than 3% for all aerosol types, even for extinction coefficients as large as 3.9 km(-1). Thus, for ground-based lidar measurements and typical meteorological conditions, errors caused by neglecting multiple scattering are by far less significant than other errors in lidar data evaluation.

Hematopoietic donor chimerism and graft-versus-myeloma effect in relapse of multiple myeloma after allogeneic bone marrow transplantation

A large group of patients relapsing after allogeneic bone marrow transplantation (BMT) have obtained remission after infusion of leukocytes from their original donor, suggesting a graft-versus-myeloma effect. However, side effects such as graft-versus-host disease and myelosuppression are severe, and sometimes fatal, complications of this therapeutic approach. Previously we demonstrated that patients with leukemia who lack donor hematopoiesis in relapse after BMT experience severe and lasting aplasia after infusion of donor leukocytes. In two patients - one with extramedullary and one with marrow relapse after a sex-mismatched transplantation - we analyzed hematopoietic chimerism by cell sorting and bone marrow cultures. CD34-positive cells, CD4-CD8-positive cells, committed progenitors, and LTC-IC were of donor origin, as demonstrated by two-color fluorescence in situ hybridization (FISH). Additionally, in relapse complete donor T-cell chimerism was seen. In contrast, plasma cells were of recipient origin in the patient who had a relapse in the bone marrow. Both patients were treated with infusions of donor leukocytes from their original donor. Neither patient suffered myelosuppression, and one achieved a stable complete remission.