Paroxysmal nocturnal hemoglobinuria in a patient post COVID-19 virus infection: A case report with literature review.

COVID 19 is a serious infection that originated in Wuhan, China and has resulted in worldwide morbidity and mortality. It continues to be a major health concern in 2022, being associated with multiorgan failure. Although the pathophysiology of the disease and its complications are not well understood, it is believed that a cytokine storm, triggered by complement activation may be responsible for the severity and complications of the disease. As of now, there is no definitive treatment available. Hematological changes associated with COVID-19 include lymphopenia, anemia, thrombocytopenia, disseminated intravascular coagulopathy, and thrombosis. Paroxysmal nocturnal hemoglobinuria (PNH), on the other hand, is an acquired clonal hematopoietic stem cell disorder that occurs due to an acquired PIG-A mutation affecting the hematopoietic stem cells. Interestingly, PNH exhibits some clinical and laboratory manifestations like those seen in COVID-19. In this report, we present a rare case of PNH that developed following a COVID-19 infection.

Identification of Potential Therapeutic Targets for Plasmablastic Lymphoma Through Gene Expression Analysis: Insights into RAS and Wnt Signaling Pathways.

Plasmablastic lymphoma (PBL) is a rare and aggressive B-cell lymphoma with overlapping characteristics with diffuse large B-cell lymphoma (DLBCL) and multiple myeloma. Hyperactive Wnt signaling derails homeostasis and promotes oncogenesis and chemoresistance in DLBCL and multiple myeloma. Evidence suggests active cross-talk between the Wnt and RAS pathways impacting metastasis in solid cancers in which combined targeted therapies show effective results. Recent genomic studies in PBL demonstrated a high frequency of mutations linked with the RAS signaling pathway. However, the role of RAS and Wnt signaling pathway molecule expression in PBL remained unknown. We examined the expression of Wnt and RAS pathway-related genes in a well-curated cohort of PBL. Because activated B cells are considered immediate precursors of plasmablasts in B cell development, we compared this data with activated B-cell type DLBCL (ABC-DLBCL) patients, employing NanoString transcriptome analysis (770 genes). Hierarchical clustering revealed distinctive differential gene expression between PBL and ABC-DLBCL. Gene set enrichment analysis labeled the RAS signaling pathway as the most enriched (37 genes) in PBL, including upregulating critical genes, such as NRAS, RAF1, SHC1, and SOS1. Wnt pathway genes were also enriched (n = 22) by gene set enrichment analysis. Molecules linked with Wnt signaling activation, such as ligands or targets (FZD3, FZD7, c-MYC, WNT5A, WNT5B, and WNT10B), were elevated in PBL. Our data also showed that, unlike ABC-DLBCL, the deranged Wnt signaling activity in PBL was not linked with hyperactive nuclear factor κB and B-cell receptor signaling. In divergence, Wnt signaling inhibitors (CXXC4, SFRP2, and DKK1) also showed overexpression in PBL. The high expression of RAS signaling molecules reported may indicate linkage with gain-in-function RAS mutations. In addition, high expression of Wnt and RAS signaling molecules may pave pathways to explore benefiting from combined targeted therapies, as reported in solid cancer, to improve prognosis in PBL patients.

"Losing the Brakes"-Suppressed Inhibitors Triggering Uncontrolled Wnt/ß-Catenin Signaling May Provide a Potential Therapeutic Target in Elderly Acute Myeloid Leukemia.

Dysregulated Wnt/ß-catenin signal transduction is implicated in initiation, propagation, and poor prognosis in AML. Epigenetic inactivation is central to Wnt/ß-catenin hyperactivity, and Wnt/ß-catenin inhibitors are being investigated as targeted therapy. Dysregulated Wnt/ß-catenin signaling has also been linked to accelerated aging. Since AML is a disease of old age (>60 yrs), we hypothesized age-related differential activity of Wnt/ß-catenin signaling in AML patients. We probed Wnt/ß-catenin expression in a series of AML in the elderly (>60 yrs) and compared it to a cohort of pediatric AML (<18 yrs). RNA from diagnostic bone marrow biopsies (n = 101) were evaluated for key Wnt/ß-catenin molecule expression utilizing the NanoString platform. Differential expression of significance was defined as >2.5-fold difference (p < 0.01). A total of 36 pediatric AML (<18 yrs) and 36 elderly AML (>60 yrs) were identified in this cohort. Normal bone marrows (n = 10) were employed as controls. Wnt/ß-catenin target genes (MYC, MYB, and RUNX1) showed upregulation, while Wnt/ß-catenin inhibitors (CXXR, DKK1-4, SFRP1-4, SOST, and WIFI) were suppressed in elderly AML compared to pediatric AML and controls. Our data denote that suppressed inhibitor expression (through mutation or hypermethylation) is an additional contributing factor in Wnt/ß-catenin hyperactivity in elderly AML, thus supporting Wnt/ß-catenin inhibitors as potential targeted therapy.

Genotype and Phenotype of Adenosine Deaminase 2 Deficiency: a Report from Saudi Arabia.

Adenosine deaminase 2 deficiency (DADA2), a rare and potentially fatal systemic autoinflammatory disease, is characterized by low or lack of ADA2 activity due to ADA2 mutations. DADA2 symptoms are variable and include vasculitis, immunodeficiency, and cytopenia. Minimal data are available from Saudi Arabia. This retrospective study conducted at seven major tertiary medical centers examined the phenotypic and genotypic variabilities, clinical and diagnostic findings, and treatment outcomes among 20 Saudi patients with DADA2 from 14 families. The median age of the study cohort was 9.5 years (4-26 years). The clinical presentation was before the age of 5 months in 25% of patients. Homozygous c.1447-1451del mutation was the most frequent ADA2 alteration (40%), followed by c.882-2A:G (30%). All tested patients exhibited absent or near-absent ADA2 activity. Phenotypic manifestations included stroke (40%), hematological abnormalities (95%), lymphoproliferation (65%), and recurrent infection (45%). Five and three patients had extracranial vasculitis features and Hodgkin lymphoma, respectively. Atypical manifestations included growth retardation (30%) and transverse myelitis. Anti-tumor necrosis factor (anti-TNF) therapy was the main treatment. Some patients underwent blood transfusion, splenectomy, cyclosporine and colony-stimulating factor therapies, and hematopoietic stem cell transplantation due to anti-TNF therapy failure. Fulminant hepatitis and septic multiorgan failure caused mortality in three patients. Thus, this study revealed the variability in the molecular and clinical characteristics of DADA2 in the study cohort with predominant aberrant hematological and immunological characteristics. Consensus diagnostic criteria will facilitate early diagnosis and treatment. Additionally, disease registries or large prospective studies are needed for evaluating rare disease complications, such as cancer.

HLA Diversity in Saudi Population: High Frequency of Homozygous HLA Alleles and Haplotypes.

Human leukocyte antigens (HLA) diversity has a tremendous impact on shaping the transplantation practices, transfusion-associated graft versus host disease prevention strategies, and host-pathogen interactions. Here, we conducted a retrospective study of HLA class I and class II homozygosity at allelic and haplotype levels in unrelated individuals genotyped from 2012 to 2016 in a tertiary hospital in the capital of Saudi Arabia. Among 5,000 individuals, 2,773 individuals meet inclusion criteria and were retrospectively analyzed for HLA-A, -B, -C-DRB1, and -DQB1 homozygosity at allelic and haplotype levels. HLA molecular typing was performed using a commercial reverse sequence-specific oligonucleotide (rSSO) kit. We were able to identify 15 HLA-A, 20 HLA-B, 11 HLA-C, 13 HLA-DRB1, and five HLA-DQB1 homozygous alleles demonstrating a very low genetic diversity in the Saudi population. The highest homozygosity in HLA class I was found in locus C followed by A and B (20.3% > 16.1% > 15.5%; p < 0.001) where the most homozygote alleles were A*02 (9.2%), B*51 and B*50 (5.7% and 3.7%), and C*07, C*06, and C*15 (7.2%, 5.48%, and 3.3%) and in HLA class II, the highest homozygosity was found in locus DQB1 compared to DRB1 (31.71% > 19.2%; p < 0.001), with the most common homozygote alleles being DRB1*07 and DRB1*04 (5.33% and 4.2%) and DQB1*02, DQB1*06, and DQB1*03 (13.55%, 7.92%, and 7.64%). The frequency of finding an individual with one homozygote allele was (24.6%), two homozygote alleles (13.5%), three homozygote alleles (4.7%), four homozygote alleles (3.4%), and five alleles were (4.8%). The most frequent homozygote haplotypes are A*23∼C*06∼B*50∼DRB1*07∼DQB1*02 and A*02∼C*06∼B*50∼DRB1*07∼DQB1*02. This study shows low diversity of both class I and II alleles and haplotypes in the Saudi population, which would have a significant impact on shaping the transplantation practices, transfusion-associated graft versus host disease prevention strategies, and host-pathogen interactions.

Biallelic ZNFX1 variants are associated with a spectrum of immuno-hematological abnormalities.

Biallelic changes in the ZNFX1 gene have been recently reported to cause severe familial immunodeficiency. Through a search of our bio/databank with information from genetic testing of >55 000 individuals, we identified nine additional patients from seven families with six novel homozygous ZNFX1 variants. Consistent with the previously described phenotype, our patients suffered from monocytosis, thrombocytopenia, hepatosplenomegaly, recurrent infections, and lymphadenopathy. The two most severely affected probands also had renal involvement and clinical presentations compatible with hemophagocytic lymphohistiocytosis. The disease was less lethal among our patients than previously reported. We identified two missense changes, two variants predicted to result in complete protein loss through nonsense-mediated decay, and two frameshift changes that likely introduce a truncation. Our findings (i) independently confirm the role of ZNFX1 in primary genetic immunodeficiency, (ii) expand the genetic and clinical spectrum of ZNFX1-related disease, and (iii) illustrate the utility of large, well-curated, and continually updated genotype-phenotype databases in resolving molecular diagnoses of patients with initially negative genetic testing findings.

Clinicopathologic features and therapy outcome in childhood Hodgkin's lymphoma: a report from tertiary care center in Saudi Arabia.

BACKGROUND: Hodgkin lymphoma (HL) is lymphoid neoplasm usually affecting lymphatic system; it accounts 3.6% of cancers in Saudi Arabia. Modern treatment protocols had shown particular success rates in overall-survival (OS) and event-free-survival (EFS). In our study, we reviewed the medical records of 80 pediatric and young adolescent patients diagnosed HL from January 2006 to July 2020, treated at tertiary care hospital in Riyadh, Saudi Arabia. Demographic, clinical, and pathological data were explored. First line therapy was ABVD, COG, COPP, R-CHOP, or radiotherapy alone in 53/80 (66.4%), 24/80 (30%), 1/80 (1.2%), 1/80 (1.2%), or 1/80 (1.2%) patients; respectively. Response assessment was done by CT + / - PET scan after first 2 cycles then every 2 cycle and end of therapy. Another assessment was done if any clinical suspicion of recurrence. RESULTS: Median age 11 (range 3-16) years. Males to females 1.3:1. Seventy-two out of eighty (90%) patients showed first complete remission (CR1) and maintained remission for median 40 (range 7-136) months. Eight out of eighty (10%) patients showed refractory disease. Nineteen patients received salvage therapy (ICE or ESHAP/brentuximab vedotin or gemcitabine/brentuximab vedotin), 14/19 (73.7%) had 2nd complete remission (CR2) for median time 24 (ranged 9-78) months, while 5/19 (26.3%) did not show any response. Five-year OS and EFS were 95% and 75%. Two patients had 2ry malignant neoplasms, one had AML and died, the other had malignant fibrous histocytoma and still alive. None of our patients had fertility problem. Also, they did not experience chronic pulmonary or cardiotoxicity. Classic Hodgkin's lymphoma: nodular sclerosis subtype was more prominent (55%) than mixed cellularity subtype (22.5%), which is similar to several European and US studies, lymphocyte rich (11.25%) and lymphocyte depleted (0%), while nodular lymphocyte predominant Hodgkin's lymphoma (11.25%). CONCLUSIONS: Our study provided unique descriptive study of childhood HL, in Saudi Arabia, with valuable insight into the long-term outcome and late toxicity. Our results are comparable to other studies in the Middle East and European countries.

Assessment of Health-related Quality of Life in Saudi Children with Cancer.

Advances in pediatric cancer treatment and dramatic improvement in long-term survival have made health-related quality of life (HRQOL) a priority. This study describes the HRQOL of Saudi children on cancer treatment, given the paucity of data on the subject. Parents of children undergoing cancer treatment between the ages of 2 and 12 years enrolled to answer the Arabic version of the parent proxy report PedsQL™ 3.0 cancer module. The module items were reverse-scored to a linear scale from 0 to 100, in which higher scores indicated a better HRQOL. Of the 95 study participants, 61 (64.2%) were hematological malignancies and 34 (35.8%) solid malignancies. The mean score of our sample's total HRQOL was 72.3, which is in line with the results of similar studies worldwide. The lowest scores were observed for procedural anxiety (60.14), perceived physical appearance (67.37), and treatment anxiety (67.58), while the highest were for communication (80.21), nausea (78.32), and cognitive problems (78.32). Significant associations were reported between the patients aged younger than 5 years and procedural anxiety, those aged 5 years or older and perceived physical appearance, and frequent hospital visits and worry. Healthcare professionals should consider the poor HRQOL sub-scales and their associated risks to improve treatment outcomes.

Diagnostic accuracy of reticulocyte parameters on the sysmex XN 1000 for discriminating iron deficiency anaemia and thalassaemia in Saudi Arabia.

INTRODUCTION: Iron deficient erythropoiesis and Thalassaemia are both associated with microcytic erythropoiesis albeit from different pathological mechanisms. Given the high prevalence of Hemoglobinopathies in the Mediterranean region, discriminating these two conditions is important. Several algorithms using conventional red cell indices have been developed to facilitate diagnosis, however, their diagnostic accuracy is low. The new generation haematology analyzers enabled the use of more innovative parameters such as reticulocyte parameters. We aimed to evaluate the diagnostic performance of the reticulocyte parameters on the Sysmex XN 1000 to distinguish between IDA and Thalassemia in our population. METHODS: We performed a retrospective analysis of blood samples sent to our laboratory for haemoglobin electrophoresis screening. We categorized our cohort into Thalassemia and Iron Deficient patients based on known diagnostic criteria. We analyzed the reticulocyte parameters using receiver operator curve analysis (ROC) and determined the cut off value for each parameter. RESULTS: Reticulocyte parameters most accurate for discriminating IDA from Thalassemia patients was: RET, RET-HE and IRF. The RET-HE had the best statistical significance for IDA patients with AUC = 0.69 for cut off 22.25. The RET-HE for dual positive patients was more accurate with AUC = 0.78 for cut off 21.25. The IRF had the best statistical significance for Alpha Thalassemia with AUC = 0.66 for cut off value 18. CONCLUSION: An IRF cut off below 15.5 and RET-HE cut off below 22.25 was the most accurate variable in predicting IDA with a sensitivity of 59.4% and 68.3%.

Cytological Diagnosis of Plasmablastic Lymphoma Involving the Parotid Gland: A Case Report with Review of the Literature.

Plasmablastic lymphoma (PBL) is a rare subtype of non-Hodgkin's lymphoma that is associated with acquired immunodeficiency syndrome (AIDS), characterized by its association with Epstein-Barr virus (EBV), aggressive nature, and plasmacytic/plasmablastic differentiation. PBL remains a therapeutic and diagnostic challenge. Diagnosis of PBL by fine-needle aspiration cytology (FNAC) is reported infrequently. We herein describe the cytodiagnosis of a rare case of HIV-negative PBL in a 58-year-old man without EBV infection presented by parotid swelling. The current case study highlights the cytomorphologic features that may help to distinguish PBL from other mimics. However, although the cytomorphologic features may suggest PBL, a definitive diagnosis requires additional studies including tissue biopsy and immunohistochemistry, in addition to biochemical investigations and radiological workup to establish the diagnosis and exclude similar conditions. In conclusion, FNAC is a very useful, simple, rapid and reliable procedure for diagnosis of the lymphoma. FNAC provided the earliest clue to diagnosis of PBL, which was later confirmed by tissue biopsy.

Unusual presentation of COVID-19 in a child complicated by massive acute pulmonary embolism and lung infarction.

The Novel Coronavirus 2019 (SARSCoV- 2), which was first reported on in Wuhan, China, in late December 2019, causes a respiratory illness called COVID- 19 Disease. COVID-19 is most likely causing a hypercoagulable state, however the prevalence of acute venothromboembolism is still unknown. Limited data suggest pulmonary microvascular thrombosis may play a role in progressive respiratory failure. Here, we report a case of a child with an unusual presentation of COVID-19 presented initially by dry cough without fever and complicated by massive acute pulmonary embolism and lung infarction and treated successfully by hydroxychloroquine and azithromycin, in addition to anticoagulant therapy.

Gene Expression Analysis of Pediatric Acute Myeloid Leukemia Identified a Hyperactive ASXL1/BAP1 Axis Linked with Poor Prognosis and over Expressed Epigenetic Modifiers.

Genetic aberrations in the epigenome are rare in pediatric AML, hence expression data in epigenetic regulation and its downstream effect is lacking in childhood AML. Our pilot study screened epigenetic modifiers and its related oncogenic signal transduction pathways concerning clinical outcomes in a small cohort of pediatric AML in KSA. RNA from diagnostic BM biopsies (n = 35) was subjected to expression analysis employing the nCounter Pan-Cancer pathway panel. The patients were dichotomized into low ASXL1 (17/35; 49%) and high ASXL1 (18/35; 51%) groups based on ROC curve analysis. Age, gender, hematological data or molecular risk factors (FLT3 mutation/molecular fusion) exposed no significant differences across these two distinct ASXL1 expression groups (P > 0.05). High ASXL1 expression showed linkage with high expression of other epigenetic modifiers (TET2/EZH2/IDH1&2). Our data showed that high ASXL1 mRNA is interrelated with increased BRCA1 associated protein-1 (BAP1) and its target gene E2F Transcription Factor 1 (E2F1) expression. High ASXL1 expression was associated with high mortality {10/18 (56%) vs. 1/17; (6%) P < 0 .002}. Low ASXL1 expressers showed better OS {740 days vs. 579 days; log-rank P= < 0.023; HR 7.54 (0.98-54.1)}. The association between high ASXL1 expression and epigenetic modifiers is interesting but unexplained and require further investigation. High ASXL1 expression is associated with BAP1 and its target genes. Patients with high ASXL1 expression showed poor OS without any association with a conventional molecular prognostic marker.

Rare tumors in pediatric age group: Single center experience from Saudi Arabia.

Rare pediatric tumors are heterogeneous group containing a variety of histopathological diseases, they represent approximately 10% of all childhood cancers. These rare tumors had a diversity of histology and clinical behaviors that pose different challenges to the investigators. Exploring different pediatric rare tumors. The data were reviewed, retrospectively, through the medical records of seven rare pediatric diseases between 2012 and 2019. Giant cell fibroblastoma (GCF) presented as painless swelling in the trunk, positive for CD34 with PTEN gene mutation. Neuroglial heterotopic tissue presented in 7 days old girl with facial asymmetry and bulging in the oral cavity, maximal de-bulking was done, histopathology was positive for GFAP and S100p. Left side neck mass, surgically excised revealed non-metastatic salivary grand mucoepidermoid carcinoma. Follow up without any chemotherapy or radiotherapy for 5 years with complete remission. Mesenchymal chondrosarcoma (MCS) presented in maxillofacial bones by persistent nasal bleeding, HEY1-NCOA2 fusion gene confirmed the diagnosis. Extra-osseous Ewing sarcoma (EES) presented as rubbery painless swelling in the scalp with fusion transcript involving EWSR1-FL11. Juvenile xanthogranuloma (JXG) presented by butter fly like skin patch in the face with foamy histiocytes in upper dermis with few Touton giant cells, extensive systemic involvement of lung and bone marrow. Metastatic ovarian choriocarcinoma with choriocarcinoma syndrome received induction two different lines of chemotherapy and consolidated with autologous stem cell transplant. Seven pediatric rare tumors, with different aspects of challenges in diagnosis and management, despite the absence of formal protocols and rarity of other center experiences.

Wolman's disease presenting with secondary hemophagocytic lymphohistiocytosis: a case report from Saudi Arabia and literature review.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially fatal syndrome that is characterized by strong activation of the immune system from hyperinflammatory cytokines. Symptoms of HLH patients include fever, hepatosplenomegaly, cytopenia, and hyperferritinemia. Inherited HLH is classified as primary, whereas secondary HLH (sHLH) occurs when acquired from non-inherited reasons that include severe infection, immune deficiency syndrome, autoimmune disorder, neoplasm, and metabolic disorder. Wolman's disease (WD) is a rare and fatal infantile metabolic disorder caused by lysosomal acid lipase deficiency, that exhibits similar clinical signs and symptoms as HLH. This paper reports the case of an infant diagnosed with WD and who presented with sHLH. CASE PRESENTATION: A 4-month-old infant presenting with hepatosplenomegaly, failure to thrive, and other abnormalities. WD diagnosis was confirmed by the presence of the LIPA gene homozygous deletion c.(428 + 1_967-1)_(*1_?)del. The infant also met the HLH-2004 diagnostic criteria. CONCLUSIONS: Metabolic disorder such as WD should be investigated in infants fulfilling the HLH criteria to diagnose the underlying condition. More studies are needed to understand the link between WD and sHLH and to identify appropriate therapies.

The Impact of COVID-19 Pandemic in Children With Cancer: A Report From Saudi Arabia.

In January 2020, the WHO declared the novel coronavirus (2019-nCoV) outbreak as a public health emergency of international concern. Due to the rapid spread of 2019-nCoV, all countries started preventive and precautionary measures to prevent COVID-19 infection spread. These measures limited the population mobility and services provided, which subsequently Impact of on children with cancer and cancer care delivery in the many health centers in Saudi Arabia. We did a cross-sectional study to assess the impact of this outbreak on children with cancer concerning all aspects of life including medical services provided, the specific precautions to prevent spread in cancer patients, mental, psychological effects, and its effect on the quality of life. We collected 204 responses during a survey that assessed the impact on the treatment of cancer children at a tertiary institution during the COVID-19 pandemic. The majority of patients were receiving ongoing chemotherapy for leukemia/lymphoma. The majority of these patients (60.5%) reported a delay in treatment received due to hospital cancellation of appointments due to the pandemic. Although the majority of patients in our cohort complained of delayed treatment, fortunately, none of the delays led to fatalities. In the context of global lockdowns and physical distancing to help flatten the COVID-19 curve, telemedicine has proved fundamental to keeping patients and their healthcare providers connected and safe. Children also faced multiple other difficulties such as psychosocial issues during the COVID-19 pandemic. Our long-term goals are to develop new programs that will enable children with cancer to emerge successfully during a pandemic.

Rare cytogenetic abnormalities and their clinical relevance in pediatric acute leukemia of Saudi Arabian population.

BACKGROUND: Childhood Acute Leukemia (AL) is characterized by recurrent genetic aberrations in 60% of AML cases and 90% of ALL cases. Insufficient data exists of rare cytogenetic abnormalities in AL. Therefore, we tested rare cytogenetic abnormalities occurring in childhood AL and its effect on clinical prognosis in patients diagnosed at our institution from 2010 to 2017. RESULTS: Among 150 cases of AL, we detected 9 cases with rare chromosomal abnormalities. We found two hypodiploid (2n-) cases: 2n-,t (5;14)(q31;q32) and t (3;11;19)(q21;q23;q13.1) in ALL patients. AML patients showed t (7;14)(q22;q32), t (11;17)(p15;q21), t (11;20) (p15;q11), t (12;17)(q15;q23) and t (11;20)(p15;q11). Both t (1;15)(q10;q10) and t (17;19)(q21;p13.3) occurred in a case with biphenotypic AL. Complete remission (CR) status was attained in 3 patients and 6 patients never attained CR or relapsed/demised. CONCLUSION: The study highlighted that rare cytogenetic abnormalities are associated with a poor prognosis. This finding is not well reported in the literature suggesting that ongoing cytogenetic studies for rare abnormalities associated with pediatric leukaemia are warranted.

Diffuse large B-cell lymphoma in Southeast Asian cohort: expression patterns of B-cell receptor (BCR) repertoire and its linkage with molecular subtypes and response to R-CHOP therapy.

AIMS: Heightened B-cell receptor (BCR) activity in diffuse large B-cell lymphoma (DLBCL) is well established, and a subset of patients with relapsed DLBCL can benefit from BCR-targeted therapies. Universal outreach of such emerging therapies mandates forming a global landscape of BCR molecular signalling in DLBCL, including Southeast Asia. METHODS: 79 patients with DLBCL (nodal, 59% and extranodal, 41%) treated with rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) therapy were selected. Expression levels of BCR and linked signalling pathway molecules were inter-related with Lymph2Cx-based cell of origin (COO) types and overall survival (OS). RESULTS: Activated B-cell (ABC) type DLBCL constituted 49% (39/79) compared with germinal centre B-cell (GCB) type DLBCL (29/79; 37%) and revealed poor prognosis (p=0.013). In ABC-DLBCL, high BTK expression exerted poor response to R-CHOP, while OS in ABC-DLBCL with low BTK expression was similar to GCB-DLBCL subtype (p=0.004). High LYN expression coupled with a poor OS for ABC-DLBCL as well as GCB-DLBCL subtypes (p=0.001). Furthermore, high coexpression of BTK/LYN (BTK high/LYN high) showed poor OS (p=0.019), which linked with upregulation of several genes associated with BCR repertoire and nuclear factor-kappa B pathway (p<0.01). In multivariate analysis, high BTK and LYN expression retained prognostic significance against established clinical predictive factors such as age, International Prognostic Index and COO (p<0.05). CONCLUSIONS: Our data provide a clear association between high BCR activity in DLBCL and response to therapy in a distinct population. Molecular data provided here will pave the pathway for the provision of promising novel-targeted therapies to patients with DLBCL in Southeast Asia.

Routine Preoperative Coagulation Tests in Children Undergoing Elective Surgery or Invasive Procedures: Are They Still Necessary?

INTRODUCTION: Preoperative coagulation screening tests in pediatric patients was once routine clinical practice globally and still used as standard practice in some countries before surgical procedures to assess of perioperative bleeding risk. OBJECTIVE: The study aimed to evaluate unselected routine preoperative coagulation testing in children undergoing elective or invasive surgery to predict abnormal perioperative bleeding. The study also aimed to provide a rational approach of determining bleeding and family history of coagulation disorders as a predictive risk for bleeding. METHODS: This retrospective study conducted between 2014 and 2015 (1 year) on normal healthy children aged under 15 years admitted to the hospitals for elective mild to intermediate surgery or invasive procedures. We reviewed and collected the details of the clinical history, previous surgery, trauma, family history, detail of anti-thrombotic medication and coagulation tests performed (prothrombin time (PT), the activated partial prothrombin time (APTT), and international normalized ratio (INR)) at the time of admission. RESULTS: Among 2078 cases, 1940 cases had normal coagulation tests (93.4%), 77 cases had abnormal coagulation results (3.7%), and 61 patients underwent surgery without preoperative coagulation screening (2.9%). In 15 of 77 patients, coagulation tests were normal on repeat testing. A total of 52 were confirmed to have abnormal screening testing. Among these 52 cases, 45 had normal factors assay; where seven patients had abnormal factors assay. Postoperative bleeding occurred only in three cases (0.14%), two cases due to surgical procedures with normal preoperative testing and one due to hemophilia A which was detected postoperatively as no preoperative testing was performed. CONCLUSIONS: Routine coagulation screening before surgery or invasive procedures to predict perioperative bleeding in unselected patients is not recommended. Our study emphasizes that selective preoperative testing is more appropriate. Selective criteria for consideration of the latter includes physical examination, type of surgery, family and bleeding history, and concomitant use of antiplatelet and anti-thrombotic therapy.