CRISPR/Cas9-Mediated Foxp1 Silencing Restores Immune Surveillance in an Immunocompetent A20 Lymphoma Model

The interaction of lymphoma cells with their microenvironment has an important role in disease pathogenesis and is being actively pursued therapeutically using immunomodulatory drugs, including immune checkpoint inhibitors. Diffuse large B-cell lymphoma (DLBCL) is an aggressive high-grade disease that remains incurable in ~40% of patients treated with R-CHOP immunochemotherapy. The FOXP1 transcription factor is abundantly expressed in such high-risk DLBCL and we recently identified its regulation of immune response signatures, in particular, its suppression of the cell surface expression of major histocompatibility class II (MHC-II), which has a critical role in antigen presentation to T cells. Using CRISPR/Cas9 genome editing we have depleted Foxp1 expression in the aggressive murine A20 lymphoma cell line. When grown in BALB/c mice, this cell line provides a high-fidelity immunocompetent disseminated lymphoma model that displays many characteristics of human DLBCL. Transient Foxp1-depletion using siRNA, and stable depletion using CRISPR (generated by independently targeting Foxp1 exon six or seven) upregulated cell surface I-Ab (MHC-II) expression without impairing cell viability in vitro. RNA sequencing of Foxp1-depleted A20 clones identified commonly deregulated genes, such as the B-cell marker Cd19, and hallmark DLBCL signatures such as MYC-targets and oxidative phosphorylation. Immunocompetent animals bearing Foxp1-depleted A20 lymphomas showed significantly-improved survival, and 20% did not develop tumors; consistent with modulating immune surveillance, this was not observed in immunodeficient NOD SCIDγ mice. The A20 Foxp1 CRISPR model will help to further characterize the contribution of Foxp1 to lymphoma immune evasion and the potential for Foxp1 targeting to synergize with other immunotherapies.

The relationship between sarcopenia and survival at 1 year in patients having elective colorectal cancer surgery

Background

Colorectal cancer remains a common cause of cancer death in the UK, with surgery being the mainstay of treatment. An objective measurement of the suitability of each patient for surgery, and their risk–benefit calculation, would be of great utility. We postulate that sarcopenia (low muscle mass) could fulfil this role as a prognostic indicator. The aim of this study was to determine the relationship between sarcopenia and long-term outcomes in patients undergoing elective bowel resection for colorectal cancer.

Methods

One hundred and sixty-three consecutive patients who had elective curative colorectal resection for cancer were eligible for inclusion in the study. Psoas muscle mass was assessed on preoperative computed tomography scan at the level of the L3 vertebra and standardised for patient height (total psoas index, TPI). Sarcopenia (low muscle mass) was defined as < 524 mm²/m² in males and 385 mm²/m² in females. In addition to clinical–pathological parameters, postoperative complications were recorded and patients were followed up for mortality for 1 year after surgery.

Results

Sarcopenia was present in 19.6% of the study participants and was significantly related to body mass index (p = 0.007), 30-day mortality (p = 0.042) and 1-year mortality (p = 0.046). In univariate analysis, American Society of Anesthesiologists grade (p = 0.016), tumour stage (p = 0.018) and sarcopenia (p = 0.043) were found to be significant independent predictors of 1-year mortality.

Conclusions

This study has found sarcopenia to be prevalent in patients with colorectal cancer having elective surgery. Independent of age, sarcopenia was associated with poorer 30-day mortality and survival at 1 year. Measurement of muscle mass preoperatively could be used to stratify a patient’s risk, allowing targeted strategies such as prehabilitation, to be implemented to modify sarcopenia and improve long-term outcomes for patients.

A comparison of four different imaging modalities - Conventional, cross polarized, infra-red and ultra-violet in the assessment of childhood bruising

Background

It is standard practice to image concerning bruises in children. We aim to compare the clarity and measurements of bruises using cross polarized, infra-red (IR) and ultra-violet (UV) images to conventional images.

Methods

Children aged <11 years with incidental bruising were recruited. Demographics, skin and bruise details were recorded. Bruises were imaged by standard protocols in conventional, cross-polarized, IR and UV lights. Bruises were assessed in vivo for contrast, uniformity and diffuseness, and these characteristics were then compared across image modalities. Color images (conventional, cross polarized) were segmented and measured by ImageJ. Bruises of grey scale images (IR, UV) were measured by a ‘plug in’ of ImageJ. The maximum and minimum Feret's diameter, area and aspect ratio, were determined. Comparison of measurements across imaging modalities was conducted using Wilcoxon rank sum tests and modified Bland-Altman graphs. Significance was set at p < 0.05.

Results

Twenty five children had 39 bruises. Bruises that were of low contrast, i.e. difficult to distinguish from surrounding skin, were also more diffuse, and less uniformity in vivo. Low contrast bruises were best seen on conventional and cross-polarized images and less distinctive on IR and UV images. Of the 19 bruises visible in all modalities, the only significant difference was maximum and minimum Feret's diameters and area were smaller on IR compared to conventional images. Aspect ratios were not affected by the modality.

Conclusions

Conventional and cross-polarized imaging provides the most consistent bruise measurement, particularly in bruises that are not easily distinguished from surrounding skin visually.

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Diffuse bruises may be measured on conventional & cross polarized imaging.

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Infrared or ultraviolet imaging may not show bruises which are difficult to see in vivo.

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Measurements of bruises using infrared imaging may be smaller than other modalities.

Optimising the measurement of bruises in children across conventional and cross polarized images using segmentation analysis techniques in Image J, Photoshop and circle diameter measurements

BACKGROUND

Bruising is a common abusive injury in children, and it is standard practice to image and measure them, yet there is no current standard for measuring bruise size consistently. We aim to identify the optimal method of measuring photographic images of bruises, including computerised measurement techniques.

METHODS

24 children aged <11 years (mean age of 6.9, range 2.5-10 years) with a bruise were recruited from the community. Demographics and bruise details were recorded. Each bruise was measured in vivo using a paper measuring tape. Standardised conventional and cross polarized digital images were obtained. The diameter of bruise images were measured by three computer aided measurement techniques: Image J (segmentation with Simple Interactive Object Extraction (maximum Feret diameter), 'Circular Selection Tool' (Circle diameter), & the Photoshop 'ruler' software (Photoshop diameter)). Inter and intra-observer effects were determined by two individuals repeating 11 electronic measurements, and relevant Intraclass Correlation Coefficient's (ICC's) were used to establish reliability. Spearman's rank correlation was used to compare in vivo with computerised measurements; a comparison of measurement techniques across imaging modalities was conducted using Kolmogorov-Smirnov tests. Significance was set at p < 0.05 for all tests.

RESULTS

Images were available for 38 bruises in vivo, with 48 bruises visible on cross polarized imaging and 46 on conventional imaging (some bruises interpreted as being single in vivo appeared to be multiple in digital images). Correlation coefficients were >0.5 for all techniques, with maximum Feret diameter and maximum Photoshop diameter on conventional images having the strongest correlation with in vivo measurements. There were significant differences between in vivo and computer-aided measurements, but none between different computer-aided measurement techniques. Overall, computer aided measurements appeared larger than in vivo. Inter- and intra-observer agreement was high for all maximum diameter measurements (ICC's > 0.7).

CONCLUSIONS

Whilst there are minimal differences between measurements of images obtained, the most consistent results were obtained when conventional images, segmented by Image J Software, were measured with a Feret diameter. This is therefore proposed as a standard for future research, and forensic practice, with the proviso that all computer aided measurements appear larger than in vivo.

Donegal Going against the Flow: National Differences in Long-Term Urinary Catheterisation Rates in Men (> 65 Years) With Benign Prostatic Hypertrophy

An analysis of Primary Care Reimbursement Service (PCRS, 2013) data demonstrated high rates of urinary catheter changes in Donegal compared to other regions of Ireland. There is a catheter change rate of 10.2% in Donegal men over 65 with medical cards (GMS) compared to rates of 2.7% and 0.17% in Waterford and South Dublin, respectively1. This 60-fold difference between an area with perceived good access to services (South Dublin) and Donegal an area that does not, prompted a survey of general practitioners in each of these areas to assess whether true male catheterisation rates were similarly disproportionate in Donegal. Based on this, data was collected from a population of 23,794 GMS patients in GP training practices in Donegal (Rural), Leinster (Urban) and Waterford (Suburban). The data sampled for Donegal demonstrated 19 long-term catheters (LTCs per 8603 GMS) compared to four LTCs (per 5,800 GMS) in Leinster and 3 LTCs (per 9,391 GMS) in Waterford (Table 1). This anomaly in LTC rates may be a proxy for lack of access to basic Urology services.

Characteristics of non-vitreoretinal ocular injury in child maltreatment: a systematic review

PurposeTo identify the spectrum of non-vitreoretinal ocular injury due to child maltreatment.MethodsAll language search of MEDLINE, PsychINFO, EMBASE, AMED, Web of Science, and CINAHL databases, 1950-2015, was conducted.

INCLUSION CRITERIA

explicit confirmation of injury aetiology, age <18 years, examination conducted by an ophthalmologist. Exclusion: post-mortem data, organic diseases, review articles. Standardised critical appraisal and narrative synthesis was conducted of included publications by two independent reviewers.ResultsOf 1492 studies identified, 153 full texts were assessed, 49 underwent full review, resulting in five included studies: three case series and two case reports. The 26 included cases describe a wide variety of ocular, facial and skeletal injuries occurring as a consequence of child maltreatment. Ocular signs included periorbital oedema, chemosis, injection, abrasion, hyphaema, and cataract. Of interest all children that had suffered physical abuse with ocular injury had subconjunctival haemorrhages. Children presenting with abusive ocular injuries had a mean age of 13.9 months (range 1-68), while those who suffered violent corporal punishment were considerably older (mean 96 months). All cases, apart from severe corporal punishment, underwent screening for occult fractures, but neuroimaging only apparent in 2/5 eligible cases.ConclusionAlthough, the face is the most common site of abusive injury, there is a paucity of high-quality data on non-vitreoretinal ocular abusive injury. Thus, while subconjunctival haemorrhages are a potential sentinel injury of maltreatment, and may warrant further evaluation, the lack of large-scale published data limits our ability to highlight further specific characteristics of non-vitreoretinal ocular injury indicative of child abuse.

Abstract P1-05-14: Copy number aberration-induced gene breakage analysis identifies recurrent FOXP1 fusions in breast cancer

Background: Genomic instability is a critical feature of breast cancers, which manifests in genome-wide copy number aberrations (CNA), often causing “gene breakage” and the generation of fusion genes. We aimed to identify aborted transcripts with underlying CNAs and to investigate the molecular landscape of breast cancers harbouring such events.

Methods: A walking student's t-test algorithm was applied to Affymetrix Exon 1.0ST array data of 123 breast cancers to identify regions of aborted transcription and overlaid with DNA breakpoints derived from matched Affymetrix SNP6 ASCAT-segmented copy number. Aborted transcripts were investigated as potential fusion gene partners through RNA-seq analysis of 151 breast cancer samples (TCGA) and 51 breast cancer cell lines (BCCL) using ChimeraScan. Clinical correlates were established for clinicopathological features, genomic instability measures, and gene expression-based molecular classifiers including PAM50, TNBCtype, IntClust subtypes and immune signatures.

Results: One hundred and six genes with recurrent CNA-induced aborted transcription were identified. Aborted transcription showed hormone receptor subtype-specificity for 7 genes (nTNBC=1, nNon-TNBC=6) and was less prevalent in samples of IntClust 2 and IntClust 4 subtypes (p: 0.0043, 0.0011). Aborted transcripts were more frequently observed in samples with greater copy-neutral loss of heterozygosity (p=0.012), while aborted transcription of 54/106 genes significantly affected enrichment of 27 tumor-infiltrating lymphocyte subpopulations.14 aborted transcripts were found as a fusion gene with one partner in RNA-seq of TCGA and BCCL, while 19 were involved in multiple fusion events (range=1-6, median=2). Nine of 106 genes displayed gene breakage and fusion events exclusively in samples with an enriched tandem duplication phenotype. Notably, FOXP1, localised to a tumour suppressor locus at 3p14.1, reported the highest number of fusion configurations (n=6) with concurrent aborted transcription across all RNA-seq datasets (nPRADA=9, nTCGA=38, nBCCL=6).

Conclusion: CNA-induced gene breakage affects the molecular landscape of breast cancers and is linked with many genomic configurations of interest including copy-neutral loss of heterozygosity and tandem duplications. In particular, the role of recurrent gene fusions of the tumour suppressor, FOXP1, in tumourigenesis warrants further investigation.

Citation Format: Mohd Noor A, Maguire S, Watkins J, Quist J, Mirza H, Tutt A, Gillett C, Natrajan R, Grigoriadis A. Copy number aberration-induced gene breakage analysis identifies recurrent FOXP1 fusions in breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-05-14.

MEDI1873, a potent, stabilized hexameric agonist of human GITR with regulatory T-cell targeting potential

Glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) is part of a system of signals involved in controlling T-cell activation. Targeting and agonizing GITR in mice promotes antitumor immunity by enhancing the function of effector T cells and inhibiting regulatory T cells. Here, we describe MEDI1873, a novel hexameric human GITR agonist comprising an IgG1 Fc domain, a coronin 1A trimerization domain and the human GITRL extracellular domain (ECD). MEDI1873 was optimized through systematic testing of different trimerization domains, aglycosylation of the GITRL ECD and comparison of different Fc isotypes. MEDI1873 exhibits oligomeric heterogeneity and superiority to an anti-GITR antibody with respect to evoking robust GITR agonism, T-cell activation and clustering of Fc gamma receptors. Further, it recapitulates, in vitro, several aspects of GITR targeting described in mice, including modulation of regulatory T-cell suppression and the ability to increase the CD8⁺:CD4⁺ T-cell ratio via antibody-dependent T-cell cytotoxicity. To support translation into a therapeutic setting, we demonstrate that MEDI1873 is a potent T-cell agonist in vivo in non-human primates, inducing marked enhancement of humoral and T-cell proliferative responses against protein antigen, and demonstrate the presence of GITR- and FoxP3-expressing infiltrating lymphocytes in a range of human tumors. Overall our data provide compelling evidence that MEDI1873 is a novel, potent GITR agonist with the ability to modulate T-cell responses, and suggest that previously described GITR biology in mice may translate to the human setting, reinforcing the potential of targeting the GITR pathway as a therapeutic approach to cancer.

Robust anti-obesity and metabolic effects of a dual GLP-1/glucagon receptor peptide agonist in rodents and non-human primates

AIMS

To characterize the pharmacology of MEDI0382, a peptide dual agonist of glucagon-like peptide-1 (GLP-1) and glucagon receptors.

MATERIALS AND METHODS

MEDI0382 was evaluated in vitro for its ability to stimulate cAMP accumulation in cell lines expressing transfected recombinant or endogenous GLP-1 or glucagon receptors, to potentiate glucose-stimulated insulin secretion (GSIS) in pancreatic β-cell lines and stimulate hepatic glucose output (HGO) by primary hepatocytes. The ability of MEDI0382 to reduce body weight and improve energy balance (i.e. food intake and energy expenditure), as well as control blood glucose, was evaluated in mouse models of obesity and healthy cynomolgus monkeys following single and repeated daily subcutaneous administration for up to 2 months.

RESULTS

MEDI0382 potently activated rodent, cynomolgus and human GLP-1 and glucagon receptors and exhibited a fivefold bias for activation of GLP-1 receptor versus the glucagon receptor. MEDI0382 produced superior weight loss and comparable glucose lowering to the GLP-1 peptide analogue liraglutide when administered daily at comparable doses in DIO mice. The additional fat mass reduction elicited by MEDI0382 probably results from a glucagon receptor-mediated increase in energy expenditure, whereas food intake suppression results from activation of the GLP-1 receptor. Notably, the significant weight loss elicited by MEDI0382 in DIO mice was recapitulated in cynomolgus monkeys.

CONCLUSIONS

Repeated administration of MEDI0382 elicits profound weight loss in DIO mice and non-human primates, produces robust glucose control and reduces hepatic fat content and fasting insulin and glucose levels. The balance of activities at the GLP-1 and glucagon receptors is considered to be optimal for achieving weight and glucose control in overweight or obese Type 2 diabetic patients.

Electroconvulsive Therapy - What Do Patients Think Of Their Treatment?

BACKGROUND

The Regulation and Quality Improvement Authority (RQIA) monitors the administration of electroconvulsive therapy (ECT) in Northern Ireland (NI). As part of their inspection methodology RQIA wished to include feedback from ECT patients. The aim of this report is to summarise the opinions of ECT patients over a 1-year period and to compare their feedback about treatment with the standards of best practice, as defined by the Electroconvulsive Therapy Accreditation Service (ECTAS).

METHOD

RQIA was granted permission to use the ECTAS patient questionnaire. The questionnaire was distributed to all the ECT clinics in NI and staff were requested to give them to patients who had received a course of ECT.

RESULTS

A total of 42 individuals returned questionnaires, 24 females (57.1%) and 18 (42.9%) males. The response rate was 26%. Almost half of respondents were detained under the Mental Health (Northern Ireland) Order 1986 (n=19, 45.2%), with one third receiving ECT as a day patient (n=14, 33.3%). Respondents reported having detailed information about ECT, with ECTAS standards 4.2 and 4.3 being affirmed in over 80% of cases. Eighty percent of respondents (n=34) believed they benefited from ECT.

CONCLUSION

The results are mainly favourable towards ECT. The majority felt they benefited from treatment.

Child abuse and fabricated or induced illness in the ENT setting: a systematic review

BACKGROUND

Child maltreatment is persistently under-recognised. Given that a third of maltreated children may return with serious or fatal injuries, it is imperative that otolaryngologists who are in frequent contact with children are able to detect maltreatment at first presentation.

OBJECTIVE OF REVIEW

This review aims to identify ENT injuries, signs or symptoms that are indicative of physical abuse or fabricated or induced illness (child maltreatment).

TYPE OF REVIEW

Systematic review.

SEARCH STRATEGY

An all-language search, developed in Medline Ovid and consisting of 76 key words, was conducted of published and grey literature across 10 databases from inception to July 2015, for primary observational studies involving children aged <18 years.

EVALUATION METHOD

Each relevant article underwent two independent reviews with full critical appraisal, applying strict quality standards.

RESULTS

Of the 2448 studies identified and screened, 371 underwent full review, resulting in 38 included studies that detailed 122 maltreated children. Pharyngeal perforations (n = 20) were the most frequent abusive ENT injury, predominantly affecting neonates and infants, presenting with dysphagia, drooling, haemoptysis and surgical emphysema. At least 52% of children with abusive pharyngeal injuries had additional co-existent injuries. The majority of ear injuries were inflicted to the external ear (n = 11) and included auricular deformity, abrasions, petechiae, lacerations and burns. Fabricated or induced illness cases presented most commonly with recurrent, unexplained otorrhoea or ENT lesions that failed to heal despite appropriate therapy.

CONCLUSIONS

All clinicians should be familiar with the signs of child maltreatment. Pharyngeal injuries, or injuries to the external ear, presenting in young children without an explicit history of witnessed injury should prompt a child protection referral for full evaluation. Likewise, children who present with recurrent, or apparently intractable symptoms and signs despite appropriate treatment, should raise the possibility of fabricated or induced illness, and discussion with a child protection specialist is advised. Early recognition of possible child maltreatment and instigation of appropriate safeguarding measures are essential to prevent repetition and escalation of injury. This is of paramount importance to otolaryngologists, who have the potential to identify these children in their practice.

Isolated anterior mediastinal tuberculosis in an immunocompetent patient

Background

The differential diagnosis of a mediastinal mass is a common challenge in clinical practice, with a wide range of differential diagnosis to be considered. One of the rarer causes is tuberculosis. Atypical presentations of tuberculosis are well documented in immunocompromised patients, but should also be considered in the immunocompetent.

Case presentation

This case outlines a previously healthy 22 year-old immunocompetent male presenting with worsening chest pain, positional dyspnea, dry cough and dysphagia. Chest x-ray showed evidence of an isolated anterior mediastinal mass, which was confirmed on computed tomography. A mediastinoscopy was diagnostic as histology revealed necrotizing granulomatous inflammation and the presence of acid-fast bacilli, indicating mediastinal tuberculosis.

Conclusion

Typically the underlying presentation of mediastinal tuberculosis is mediastinal lymphadenitis. This case was unusual in that we detected an isolated large anterior mediastinal mass accompanied by a relatively small burden of mediastinal lymphadenitis. Cases similar to this have been documented in immunosuppressed patients however in our case no evidence of immunosuppression was found. This case report emphasizes the importance that a detailed and logical pathway of investigation is pursued when encountering a mediastinal mass.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0175-7) contains supplementary material, which is available to authorized users.

Patient journey to a specialist amyotrophic lateral sclerosis multidisciplinary clinic: an exploratory study

Background

The multidisciplinary approach in the management of Amyotrophic Lateral Sclerosis (ALS) has been shown to provide superior care to devolved care, with better survival, improved quality of care, and quality of life. Access to expert multidisciplinary management should be a standard for patients with ALS. This analysis explores the patient journey from symptom onset and first engagement with health services, to the initial visit to a specialist ALS Multidisciplinary Clinic (MDC) in Dublin, Ireland.

Methods

A retrospective exploratory multi-method study details the patient journey to the MDC. Data from medical interviews and systematic chart review identifies interactions with the health services and key timelines for thirty five new patients presenting with a diagnosis of ALS during a 6 month period in 2013.

Results

The time from first symptom to diagnosis was a mean of 16 months (median 13 months), with a mean interval of 19 months (median 14.6) from first symptoms to arrival at the MDC. The majority of patients were seen by a general practitioner, and subsequently by neurology services. There was an average of four contacts with health services and 4.8 investigations/tests, prior to their first Clinic visit. On the first visit to the MDC patients are linked into an integrated ‘system’ that can provide specialist care and link with voluntary, palliative and community services as required.

Conclusions

Engagement with a multidisciplinary team has implications for service utilization and quality of life of patients and their families. We have demonstrated that barriers exist that delay referral to specialist services. Comprehensive data recording and collection, using multiple data sources can reconstruct the timelines of the patient journey, which can in turn be used to identify pathways that can expedite early referral to specialist services.

Treating severe and enduring anorexia nervosa: a randomized controlled trial

BACKGROUND

There are no evidence-based treatments for severe and enduring anorexia nervosa (SE-AN). This study evaluated the relative efficacy of cognitive behavioral therapy (CBT-AN) and specialist supportive clinical management (SSCM) for adults with SE-AN.

METHOD

Sixty-three participants with a diagnosis of AN, who had at least a 7-year illness history, were treated in a multi-site randomized controlled trial (RCT). During 30 out-patient visits spread over 8 months, they received either CBT-AN or SSCM, both modified for SE-AN. Participants were assessed at baseline, end of treatment (EOT), and at 6- and 12-month post-treatment follow-ups. The main outcome measures were quality of life, mood disorder symptoms and social adjustment. Weight, eating disorder (ED) psychopathology, motivation for change and health-care burden were secondary outcomes.

RESULTS

Thirty-one participants were randomized to CBT-AN and 32 to SSCM with a retention rate of 85% achieved at the end of the study. At EOT and follow-up, both groups showed significant improvement. There were no differences between treatment groups at EOT. At the 6-month follow-up, CBT-AN participants had higher scores on the Weissman Social Adjustment Scale (WSAS; p = 0.038) and at 12 months they had lower Eating Disorder Examination (EDE) global scores (p = 0.004) and higher readiness for recovery (p = 0.013) compared to SSCM.

CONCLUSIONS

Patients with SE-AN can make meaningful improvements with both therapies. Both treatments were acceptable and high retention rates at follow-up were achieved. Between-group differences at follow-up were consistent with the nature of the treatments given.

In search of Pinkel's children: unravelling the biological heterogeneity of childhood acute lymphoblastic leukaemia by genotype and treatment molecular response

BACKGROUND

Acute lymphoblastic leukaemia (ALL), the commonest childhood malignancy has seen remarkable progress since the 1960s with cure rates now approaching 85%. To achieve this patients undergo intensive treatment that usually takes 2.5-3.5 years involving on average 15 different chemotherapeutic drugs. In 1971, Donald Pinkel reported Total Therapy-Protocol V that used 5 drugs and cranial radiation therapy over a similar time period. Today, one half of these patients (Pinkel's children) remain alive and free of leukaemia.

AIM

The aim of this study was to evaluate the impact post-induction minimal residual disease (MRD) levels had on survival and its relationship with the more established clinical and biological prognostic predictors of outcome in the hope of identifying a subgroup of patients that are at very low risk of failure.

METHODS

A retrospective review of 250 Irish children with ALL was carried out. MRD status after 28 days of induction chemotherapy and other known predictors of outcome were correlated with 5 year event-free survival (EFS).

RESULTS

MRD status was the strongest predictor of outcome with 5 year EFS rates greater that 90% seen in those patients with low-risk MRD and this was associated with TEL/AML1 rearrangement, high hyperdiploidy (HH) karyotype and female gender.

CONCLUSION

Both MRD and karyotype are powerful determinants of outcome in childhood ALL. Therefore, it is reasonable to conclude that the majority of children cured by Pinkel et al. in the late 1960s were most likely composed of low-risk MRD, TEL/AML1 and HH patients.