An automated Monte Carlo QC system for volumetric modulated arc therapy: Possibilities and challenges.

PURPOSE: To develop and implement an automated Monte Carlo (MC) system for patient specific VMAT quality control in a patient geometry that generates treatment planning system (TPS) compliant DICOM objects and includes a module for 3D analysis of dose deviations. Also, the aims were to recommend diagnose specific tolerance criteria and an evaluation procedure. METHODS: The EGSnrc code package formed the basis for development of the MC system. The workflow consists of a number of modules connected to a TPS by means of manual DICOM exports and imports which were executed sequentially without user interaction. DVH comparison was performed in the TPS. In addition, MC- and TPS dose distributions were analysed by applying the normalized dose difference (NDD) formalism. NDD failure maps and a pass rate for a certain threshold were obtained. 170 clinical plans (prostate, thorax, head-and-neck and gynecological) were selected for analysis. RESULTS: Agreement within 1.5% was found between clinical- and MC data for the mean dose to the target volumes and within 3% for parameters more sensitive to the shape of the DVH e.g. D98% PTV. Regarding the NDD analysis, tolerance criteria 2%/3 mm were established for prostate plans and 3%/3 mm for the rest of the cases. CONCLUSIONS: An automated MC system was developed and implemented. Evaluation procedure is recommended with NDD-analysis as a first step. For pass rate < 95%, the evaluation continues with comparison of DVH parameters. For deviations larger than 2%, a visual inspection of the clinical- and MC dose distributions is performed.

Impaired intention-to-treat survival after listing for liver transplantation in children with biliary atresia compared to other chronic liver diseases: 20 years' experience from the Nordic countries.

Biliary atresia (BA) is the most common indication for LT in children. We investigated whether this diagnosis per se, compared to other chronic liver diseases (OCLD), had an influence on patient survival. Data from 421 Scandinavian children, 194 with BA and 227 with OCLD, listed for LT between 1990 and 2010 were analyzed. The intention-to-treat survival and influencing risk factors were studied. Patients with BA had higher risk of death after listing than patients with OCLD. The youngest (<1 year) and smallest (<10 kg) children with the highest bilirubin (>510 µmol/L), highest INR (>1.6), and highest PELD score (>20) listed during 1990s had the worst outcome. Given the same PELD score, patients with BA had higher risk of death than patients with OCLD. For adolescents, low weight/BMI was the only prognostic marker. Impaired intention-to-treat survival in patients with BA was mainly explained by more advanced liver disease in younger ages and higher proportion of young children in the BA group rather than diagnosis per se. PELD score predicted death, but seemed to underestimate the severity of liver disease in patients with BA. Poor nutritional status and severe cholestasis had negative impact on survival, supporting the "sickest children first" allocation policy and correction of malnutrition before surgery.

Monte Carlo optimization of total body irradiation in a phantom and patient geometry.

The objective of this work is to apply a Monte Carlo (MC) accelerator model, validated by experimental data at isocentre distances, to a large-field total body irradiation (TBI) technique and to develop a strategy for individual patient treatment on the basis of MC dose distributions. Calculations are carried out using BEAMnrc/DOSXYZnrc code packages for a 15 MV Varian accelerator. Acceptable agreement is obtained between MC data and measurements in a large water phantom behind a spoiler at source-skin distances (SSD) = 460 cm as well as in a CIRS® thorax phantom. Dose distributions in patients are studied when simulating bilateral beam delivery at a distance of 480 cm to the patient central sagittal plane. A procedure for individual improvement of the dose uniformity is suggested including the design of compensators in a conventional treatment planning system (TPS) and a subsequent update of the dose distribution. It is demonstrated that the dose uniformity for the simple TBI technique can be considerably improved. The optimization strategy developed is straightforward and suitable for clinics where the TPS available is deficient to calculate 3D dose distributions at extended SSD.

A phase III study evaluating the efficacy and safety of MBP8298 in secondary progressive MS.

OBJECTIVE: To evaluate the efficacy and safety of MBP8298 in subjects with secondary progressive multiple sclerosis (SPMS) who express human leukocyte antigen (HLA) haplotype DR2 or DR4 (DR2(+) or DR4(+)). METHODS: This multicenter randomized 2-year, double-blind, placebo-controlled study included 612 subjects with a diagnosis of SPMS and an Expanded Disability Status Scale (EDSS) score of 3.5-6.5, stratified according to baseline EDSS score (3.5-5.0, or 5.5-6.5) and HLA haplotype (DR2(+) or DR4(+), or DR2(-)/DR4(-)). Upon entry of 100 DR2(-)/DR4(-) subjects, further study enrollment was limited to DR2(+) or DR4(+) subjects. Subjects were randomly assigned to either 500 mg MBP8298 or placebo, given by IV injection once every 6 months for 2 years. The primary outcome measure was time to progression by ≥1.0 EDSS point (or 0.5 point if baseline EDSS was 5.5 or higher), confirmed 6 months later. Secondary outcomes included mean change in EDSS, mean change in Multiple Sclerosis Functional Composite, MRI changes, annualized relapse rate, and quality of life. RESULTS: There were no significant differences between treatment groups in either the primary or secondary endpoints. MBP8298 was well tolerated in all treated subjects with no safety issues identified. CONCLUSION: In the population studied, treatment with MBP8298 did not provide a clinical benefit compared to placebo. CLASSIFICATION OF EVIDENCE: This study provides Class 1 evidence that MBP8298 is not effective in patients with SPMS who are HLA DR2(+) or DR4(+).

Intravenous synthetic peptide MBP8298 delayed disease progression in an HLA Class II-defined cohort of patients with progressive multiple sclerosis: results of a 24-month double-blind placebo-controlled clinical trial and 5 years of follow-up treatment.

MBP8298 is a synthetic peptide with a sequence corresponding to amino acid residues 82-98 of human myelin basic protein (DENPVVHFFKNIVTPRT). It represents the immunodominant target for both B cells and T cells in multiple sclerosis (MS) patients with HLA haplotype DR2. Its administration in accordance with the principle of high dose tolerance results in long-term suppression of anti-myelin basic protein (MBP) autoantibody levels in the cerebrospinal fluid (CSF) of a large fraction of progressive MS patients. MBP8298 was evaluated in a 24-month placebo-controlled double-blinded Phase II clinical trial in 32 patients with progressive MS. The objective was to assess the clinical efficacy of 500 mg of MBP8298 administered intravenously every 6 months, as measured by changes in Expanded Disability Status Scale (EDSS) scores. Contingency analysis for all patients at 24 months showed no significant difference between MBP8298 and placebo-treatments (n = 32, P = 0.29). Contingency analysis in an HLA Class II defined subgroup showed a statistically significant benefit of MBP8298 treatment compared with placebo in patients with HLA haplotypes DR2 and/or DR4 (n = 20, P = 0.01). Long-term follow-up treatment and assessment of patients in this responder group showed a median time to progression of 78 months for MBP8298 treated patients compared with 18 months for placebo-treatment (Kaplan-Meier analysis, P = 0.004; relative rate of progression = 0.23). Anti-MBP autoantibody levels in the CSF of most MBP8298 treated patients were suppressed, but antibody suppression was not predictive of clinical benefit. Anti-MBP autoantibodies that reappeared in the CSF of one patient at 36 months, whilst under treatment with MBP8298, were not reactive with the MBP8298 peptide in vitro. The identification of a responder subgroup (62.5% of the patients in this study) enables a more efficient design of a large confirmatory clinical trial of MBP8298. The probability that patients with other less common HLA-DR haplotypes will respond to this treatment should not be ignored.

Transplanted children's experiences of daily living: children's narratives about their lives following transplantation.

Transplantation is often an appropriate choice of treatment for children with end-stage renal, liver, heart or lung disease. Over the last decade, mortality and morbidity figures have been relatively stable and quality of life fairly good in children who have undergone organ transplantation. Few studies however, have focused on the experiences of transplantation from the child's perspective. The child's view is an important factor when evaluating the 'true' outcome and quality of life after transplantation. The aim of the present study was to illuminate the meaning of transplanted children's experiences of daily living. Unstructured interviews were carried out with 18 children and adolescents, aged 4-18 yr, who had undergone organ transplantation. Their narratives were transcribed and interpreted using a phenomenologic-hermeneutic method inspired by the philosophy of Ricoeur. Two main themes emerged: Being satisfied with life, with the themes: being able to live a normal life; someone who cares; coping with one's new life; and being dissatisfied with life, with the themes: not being able to live a normal life; lacking someone who cares; not being respected; existential thoughts. Most of the children and adolescents were of the opinion that they lived a normal life while the rest strived to achieve a normal life. Social support and mental support were of great importance and, when lacking, had negative consequences. Multi-disciplinary co-operation between healthcare professionals and between the healthcare system, the school and the family is crucial in order to optimize the outcome and quality of life after organ transplantation in children.

Characterization of the humoral immune response in two paediatric patients transplanted with split livers from ABO-incompatible living-related donors: appearance of cytomegalovirus-induced ABO antibodies.

Two blood group O paediatric patients, 12 and 6 months old, were transplanted with liver segments from their blood group A2Le (a(-)b+) Se and blood group A1Le (a(-)b+) Se fathers, respectively. Recipient anti-A antibody titres were reduced prior to transplantation by blood exchange. Both patients had rejection episodes in the post-transplant period that were reversed by anti-rejection therapy. No anti-A antibody titre rise occurred concomitant with these rejections. Postoperatively both patients had cytomegalovirus (CMV) infections, and simultaneous with these infections, a strong increase in anti-A antibody titres was seen, but no rejection occurred. The anti-A antibody titre increase seemed to be specific for A antigens, because the anti-B and anti-alphaGal (anti-pig) antibody titres did not show any changes. CMV infection is a serious cause of morbidity and mortality in immunosuppressed patients, and the virus can influence glycosylation of infected cells. Whether this can explain the importance of the infection in relation to the increase in titre remains to be elucidated.

Tramadol-associated pericarditis.

Tramadol, marketed as Ultram in the United States, is as a non-scheduled narcotic analgesic based on its low abuse liability. It is indicated for the treatment of moderately severe pain; however, multiple adverse effects have been reported with its use including seizures, anaphylaxis, angioedema, bronchospasm, and serotonin syndrome. An association between tramadol and pericarditis has not been previously reported. We describe the case of an 88 year-old male who developed acute pericarditis 2 days following tramadol initiation. The temporal relationship between drug initiation and pericarditis as well as the resolution of symptoms upon drug discontinuation suggested a potential association. Although pericarditis has not been described with tramadol administration, clinicians should be aware of a possible association.

Elemental versus polymeric enteral nutrition in paediatric Crohn's disease: a multicentre randomized controlled trial.

AIM: To compare the efficacy and safety of an elemental and a polymeric diet as the primary therapy for active Crohn's disease in children. METHODS: In a randomized, non-blind, multicentre, controlled trial in Sweden, 16 children with Crohn's disease received Elemental 028 Extra (E028E) and 17 Nutrison Standard (NuS). Remission rates (Paediatric Crohn's Disease Activity Index (PCDAI) < 10 or a PCDAI decrease of 40% or 15 points of initial level) were compared at 6 wk. RESULTS: There was no significant difference between the two groups in remission rate at 6 wk (intent-to-treat analysis): E028E 11/16 (69%) and NuS 14/17 (82%) (p = 0.438). There was no difference in the decrease in PCDAI and CDAI between patients treated with E028E and those treated with NuS from 0 to 6 wk. Patients treated with NuS gained significantly more weight than patients treated with E028E (+2.5 kg; 95% CI 0.9, 4.1; p = 0.004), this difference remained when adjusting for maximum caloric intake per kilogram bodyweight (+2.9 kg; 95% CI 1.4, 4.5; p = 0.001). Concomitant disease, complications and side effects were seen in 5/33 patients (pyelonephritis, pneumonia, intraabdominal abscess, perianal abscess and borborygmi). CONCLUSION: E028E and NuS did not differ in terms of remission rate. Patients treated with NuS gained more weight than patients with E028E. Polymeric diet may be superior to elemental diet in the treatment of paediatric Crohn's disease where the primary aim is to increase the patient's weight.

[Liver transplantation--from experiment to routine care. Experiences from the first 500 liver transplantations in Gothenburg]. / Levertransplantation--från experiment till rutinsjukvård. Erfarenheter från de första 500 levertransplantationerna i Göteborg.

During a fifteen-year period, 500 liver transplantations have been performed at Sahlgrenska University Hospital in Göteborg. The results have improved, and factors influencing outcome are discussed. A one-year survival rate over 90% and a 5-year survival rate close to 80% can now be expected for most indications. Long-term complications as well as special problems occurring in different groups of recipients are discussed. New indications for liver transplantation such as liver metastasis of endocrine tumors are described. This article also describes our experience of in situ splitting and living-related liver transplantation as well as other innovations such as cavoportal hemitransposition and multivisceral transplantation.

Anti-MUC-1 immunoliposomal doxorubicin in the treatment of murine models of metastatic breast cancer.

The fate of breast cancer patients is dependent upon elimination or control of metastases. We studied the effect of antibody-targeted liposomes containing entrapped doxorubicin (DXR) on development of tumours in two models of breast cancer, pseudometastatic and metastatic, in mice. The former used the mouse mammary carcinoma cell line GZHI, which expresses the human MUC-1 gene (L. Ding, E.N. Lalani, M. Reddish, R. Koganty, T. Wong, J. Samuel, M.B. Yacyshyn, A. Meikle, P.Y.S. Fung, J. Taylor-Papadimitriou, B.M. Longenecker, Cancer Immunol. Immunother. 36 (1993) 9--17). GZHI cells seed into the lungs of Balb/c mice following intravenous injection. The latter used the 4T1-MUC1 cell line, a MUC-1 transfectant of the mouse mammary carcinoma cell line 4T1, which metastasizes from a primary mammary fatpad (mfp) implant to the lungs (C.J. Aslakson, F.R. Miller, Cancer Res. 52 (1992) 1399--1405). B27.29, a monoclonal antibody against the MUC-1 antigen, was used to target sterically stabilized immunoliposomes (SIL[B27.29]) to tumour cells. In vitro, SIL[B27.29] showed high specific binding to both GZHI and 4T1-MUC1 cells. The IC(50) of DXR-loaded SIL[B27.29] was similar to that of free drug for GZHI cells. In the pseudometastatic model, mice treated with a single injection of 6 mg DXR/kg in DXR-SIL[B27.29] at 24 h after cell implantation had longer survival times than those injected with non-targeted liposomal drug. In the metastatic model, severe combined immune deficiency mice given weekly injectionsx3 of 2.5 mg DXR/kg encapsulated in either targeted or non-targeted liposomes were almost equally effective in slowing growth of the primary tumour and reducing development of lung tumours. Surgical removal of the primary tumour from mfp, followed by various chemotherapy regimens, was attempted, but removal of the primary tumour was generally incomplete; tumour regrowth occurred and metastases developed in the lungs in all treatment groups. DXR-SL reduced the occurrence of regrowth of the primary tumour, whereas neither targeted liposomal drug or free drug prevented regrowth. We conclude that monoclonal antibody-targeted liposomal DXR is effective in treating early lesions in both the pseudometastatic and metastatic models, but limitations to the access of the targeted liposomes to tumour cells in the primary tumour compromised their therapeutic efficacy in treating the more advanced lesions.

A low-level expression of human MUC1 mucin enhances lethality of murine tumor cells.

We report here the development of a mouse mammary adenocarcinoma cell line containing full-length human MUC1 cDNA that can be more lethal than the parental cell line. The metastatic murine mammary adenocarcinoma cell line 410.4 was transfected with cDNA coding for a 42-tandem-repeat version of human MUC1. Two cell lines were selected, one for stable, high expression in vitro of cell-surface MUC1 (GZHi) and one for stable, low expression in vitro of cell-surface MUC1 (GZLo). Following subcutaneous challenge of CB6F1 mice with various doses of tumor cells, GZHi tumors showed loss of MUC1 expression; negligible amounts of serum MUC1 mucin were detected and the mice survived longer than mice challenged with GZLo or wild-type (410.4) tumor cells. Mice challenged with GZLo tumor cells had shorter survival times than mice challenged with either GZHi or 410.4 tumor cells. GZLo-challenged mice that showed rapidly increasing serum MUC1 mucin levels several weeks prior to death had a shorter survival than mice without detectable rising MUC1 serum levels. Surprisingly, SCID-BEIGE mice challenged with GZLo cells also survived for a shorter time than those challenged with either GZHi or 410.4 cells. This suggests that MUC1 mucin may also enhance the aggressiveness of GZLo tumors by non-immune mechanisms.

The transcriptional response of Saccharomyces cerevisiae to osmotic shock. Hot1p and Msn2p/Msn4p are required for the induction of subsets of high osmolarity glycerol pathway-dependent genes.

We have analyzed the transcriptional response to osmotic shock in the yeast Saccharomyces cerevisiae. The mRNA level of 186 genes increased at least 3-fold after a shift to NaCl or sorbitol, whereas that of more than 100 genes was at least 1.5-fold diminished. Many induced genes encode proteins that presumably contribute to protection against different types of damage or encode enzymes in glycerol, trehalose, and glycogen metabolism. Several genes, which encode poorly expressed isoforms of enzymes in carbohydrate metabolism, were induced. The high osmolarity glycerol (HOG) pathway is required for full induction of many but not all genes. The recently characterized Hot1p transcription factor is required for normal expression of a subset of the HOG pathway-dependent responses. Stimulated expression of the genes that required the general stress-response transcription factors Msn2p and Msn4p was also reduced in a hog1 mutant, suggesting that Msn2p/Msn4p might be regulated by the HOG pathway. The expression of genes that are known to be controlled by the mating pheromone response pathway was stimulated by osmotic shock specifically in a hog1 mutant. Inappropriate activation of the mating response may contribute to the growth defect of a hog1 mutant in high osmolarity medium.

Chronic hepatitis B in children in Gothenburg, Sweden.

Sweden is a low prevalence area for hepatitis B, but the number of chronic carriers has increased during the last decade due to immigration. Out of a total of 120 children with identified chronic hepatitis B in Gothenburg, Sweden, 93 were investigated during the 2-year period 1994-95. The children had a mean age of 10.9 years and originated from 21 different countries. Most infections were discovered during various screening programmes after arrival in Sweden. A total of 90 of the 93 children were HBV-DNA positive by Amplicor HBV Monitor (Roche Diagnostics) and 58% (54/93) were HBeAg positive. All children either originated from areas with a high or medium prevalence of HBV infection (81/93, 87%) or were born in Sweden to mothers originating from high or medium prevalence countries (12/93, 13%). Three of these 12 children were vertically infected in spite of adequate immunoprophylaxis and 8 were born to mothers with undiscovered chronic HBV infection. In all, 34 children had mothers who were HBsAg positive. No overt case of transmission was notified in day-care centres or schools, or from a child to a non-immune parent. None of the children reported any symptoms of liver disease, but 38% (35/93) had elevated aminotransferases. Therefore, screening programmes are essential to identify chronic HBV infection in children in order to prevent transmission and to find individuals at risk of progressive liver damage who should be considered for treatment.