Analyzing Cancer Incidence Trends in Oman From 1996 to 2019: A Comprehensive Study of the National Cancer Annual Reports

PURPOSE

Previous studies have reported that cancer incidence trends in Oman varied by tumor site and sex. No comprehensive analysis of all cancer sites had been reported. The objective of this study is to analyze cancer incidence trends in Oman and calculate the annual percent change (APC) in age-standardized rates (ASRs) for all-cancer and 61 individual cancer sites in Omani men and women from 1996 to 2019.

METHODS

We gathered incidence data from The Omani National Cancer Registry for all cancers combined and individual tumor sites. We estimated the APC using Poisson regression.

RESULTS

The cancer ASR in the Omani population increased by 23% (from 95/100,000 in 1996 to 117.2/100,000 in 2019), with the increase being more pronounced in females (48% v 7% in males). Among the male population, there was significant increase in the ASRs of colon, rectum, thyroid, and prostate cancers, with APCs of 6.92%, 4.24%, 4.19%, and 2.03%, respectively. Among females, all-cancer incidence showed significant increase (APC = 1.39%), and increasing trends were observed in uterine, colon, rectum, thyroid, and breast cancers (APCs = 7.57%, 7.08%, 5.19%, 5.16%, and 4.19%, respectively).

CONCLUSION

The ASR of all-cancer increased significantly in Omani women but not in men. Uterine cancer had the highest APC. Colorectal cancer and thyroid ASR increased in both males and females. Breast and prostate cancers showed increasing trends. Further research is needed to explore factors contributing to increasing cancer incidences.

Deciphering Urogenital Cancers through Proteomic Biomarkers: A Systematic Review and Meta-Analysis

Urogenital cancers, which include prostate, bladder, and kidney malignancies, exert a substantial impact on global cancer-related morbidity and mortality. Proteomic biomarkers, emerging as valuable tools, aim to enhance early detection, prognostic accuracy, and the development of personalized therapeutic strategies. This study undertook a comprehensive systematic review and meta-analysis of the existing literature investigating the role and potential of proteomic biomarkers in plasma, tissue, and urine samples in urogenital cancers. Our extensive search across several databases identified 1879 differentially expressed proteins from 37 studies, signifying their potential as unique biomarkers for these cancers. A meta-analysis of the significantly differentially expressed proteins was executed, accentuating the findings through visually intuitive volcano plots. A functional enrichment analysis unveiled their significant involvement in diverse biological processes, including signal transduction, immune response, cell communication, and cell growth. A pathway analysis highlighted the participation of key pathways such as the nectin adhesion pathway, TRAIL signaling pathway, and integrin signaling pathways. These findings not only pave the way for future investigations into early detection and targeted therapeutic approaches but also underscore the fundamental role of proteomics in advancing our understanding of the molecular mechanisms underpinning urogenital cancer pathogenesis. Ultimately, these findings hold remarkable potential to significantly enhance patient care and improve clinical outcomes.

Genetic Causes, Clinical Features, and Survival of Underlying Inborn Errors of Immunity in Omani Patients: a Single-Center Study

PURPOSE

Early identification of inborn errors of immunity (IEIs) is crucial due to the significant risk of morbidity and mortality. This study aimed to describe the genetic causes, clinical features, and survival rate of IEIs in Omani patients.

METHODS

A prospective study of all Omani patients evaluated for immunodeficiency was conducted over a 17-year period. Clinical features and diagnostic immunological findings were recorded. Targeted gene testing was performed in cases of obvious immunodeficiency. For cases with less conclusive phenotypes, a gene panel was performed, followed by whole-exome sequencing if necessary.

RESULTS

A total of 185 patients were diagnosed with IEIs during the study period; of these, 60.5% were male. Mean ages at symptom onset and diagnosis were 30.0 and 50.5 months, respectively. Consanguinity and a family history of IEIs were present in 86.9% and 50.8%, respectively. Most patients presented with lower respiratory infections (65.9%), followed by growth and development manifestations (43.2%). Phagocytic defects were the most common cause of IEIs (31.9%), followed by combined immunodeficiency (21.1%). Overall, 109 of 132 patients (82.6%) who underwent genetic testing received a genetic diagnosis, while testing was inconclusive for the remaining 23 patients (17.4%). Among patients with established diagnoses, 37 genes and 44 variants were identified. Autosomal recessive inheritance was present in 81.7% of patients with gene defects. Several variants were novel. Intravenous immunoglobulin therapy was administered to 39.4% of patients and 21.6% received hematopoietic stem cell transplantation. The overall survival rate was 75.1%.

CONCLUSION

This study highlights the genetic causes of IEIs in Omani patients. This information may help in the early identification and management of the disease, thereby improving survival and quality of life.

Impact of Glutathione S-Transferase Polymorphisms on Busulfan Pharmacokinetics and Outcomes of Hematopoietic Stem Cell Transplantation

BACKGROUND

Busulfan (Bu) is an alkylating drug used in many preparative regimens before hematopoietic stem cell transplantation (HSCT). It is conjugated in the liver mainly by glutathione S-transferase isoenzyme A1-1 ( GSTA1 ). Genetic polymorphisms in these isoenzymes may affect the pharmacokinetics of Bu and the clinical outcomes of HSCT. This study aimed to assess the impact of glutathione S-transferase ( GST ) genetic polymorphisms on the clearance of Bu and the clinical outcomes of patients undergoing HSCT.

METHODS

This single-center retrospective study included patients who received IV Bu before HSCT at Sultan Qaboos University Hospital (SQUH), Oman from January 2003 to October 2016. Genotyping for polymorphisms was performed for GSTM1 , GSTT1 , GSTA1 , and GSTP1 . Each GST polymorphism was analyzed for its impact on Bu clearance and HSCT outcomes.

RESULTS

A total of 135 patients were included. The mean Bu clearance was 3.7 ± 0.98 mL/min/kg. Patients with GSTA1 A-513G heterozygosity (AG) were found to have a higher incidence of graft loss ( P = 0.006). Homozygous double null of GSTM1 and GSTT1 was associated with a higher incidence of acute graft versus host disease ( P = 0.04). Double non-null GSTM1 and GSTT1 and non-null GSTM1 increased the risk of mortality ( P = 0.034 and 0.021, respectively).

CONCLUSIONS

GST genotyping before HSCT may predict HSCT outcomes. The results of this preliminary retrospective study need to be confirmed in a larger prospective study.

Molecular blood group screening in Omani blood donors

BACKGROUND AND OBJECTIVES

Blood group genotyping has been used in different populations. This study aims at evaluating the genotypes of common blood group antigens in the Omani blood donors and to assess the concordance rate with obtained phenotypes.

MATERIAL AND METHODS

Blood samples from 180 Omani donors were evaluated. Samples were typed by serological methods for the five blood group systems MNS, RH (RHD/RHCE), KEL, FY and JK. Samples were genotyped using RBC-FluoGene vERYfy eXtend kit (inno-train©). Predicted phenotypic variants for 70 red blood cell antigens among the MNS, RH (RHD/RHCE), KEL, FY, JK, DO, LU, YT, DI, VEL, CO and KN blood group systems were assessed.

RESULTS

Simultaneous phenotype and genotype results were available in 130 subjects. Concordance rate was >95% in all blood group systems with exception of Fy(b+) (87%). Homozygous GATA-1 mutation leading to erythroid silencing FY*02N.01 (resulting in the Fy(b-)^ES phenotype) was detected in 81/112 (72%) of genotyped samples. In addition, discrepant Fy^b phenotype/genotype result was obtained in 14/112 samples; 13 of which has a heterozygous GATA-1 mutation and one sample with a wild GATA genotype. D and partial e c.733C>G variants expressing the V+VS+ phenotype were found in 22/121 (18.2%) and 14/120 (11.7%) of the samples, respectively. Di(a-b+), Js(a-b+), Yt(a+b-) and Kn(a+b-) genotype frequencies were 99.4%, 95.8%, 91.9% and 97.7%, respectively.

CONCLUSION

In conclusion, we report a high frequency of FY*02N.01 allele due to homozygous c.-67T>C GATA-1 single-nucleotide variation. This is the first study reporting the detailed distribution of common and rare red cell genotypes in Omani blood donors.

Elevated levels of circulating invariant natural killer cell subsets are skewed toward Th2-like phenotype in children with sickle cell disease

Invariant natural killer T (iNKT) cells are being considered as potential targets for immunotherapeutic strategies in a variety of conditions including sickle cell disease (SCD). However, relatively little is known about the fate of iNKT cell subsets in children with SCD. Herein, quantitative and qualitative analyses of circulating iNKT cell subsets were carried out in 120 children in steady state and 30 healthy controls. Children with SCD displayed significantly elevated levels of circulating iNKT cell subsets with a preferential polarization toward Th2-like cells. The known SCD modifiers did not influence levels of iNKT cell subsets, except that children carrying the Bantu haplotype exhibited elevated levels of CD4iNKT cells, and to a lesser degree CD8iNKT cells. Collectively, these findings indicate that circulating iNKT cell subsets are significantly increased in children with SCD, and highlight the existence of imbalanced production of cytokines toward Th2-like phenotype, which seems to be associated with genetic polymorphisms.

Correlation between flow cytometry and molecular findings in autosomal recessive chronic granulomatous disease: A cohort study from Oman

BACKGROUND

Chronic granulomatous disease (CGD) is an X-linked (XL) or autosomal recessive (AR) primary immunodeficiency disease. Respiratory burst assessment by flow cytometry is a rapid test of granulocyte stimulation, and results predict the underlying genotype. This study aims to describe the immune-phenotypic profile of patients with CGD diagnosed in our center and correlate that with underlying genetic mutations.

METHODS

Immuno-phenotypic and genetic data on all patients with CGD diagnosed at Sultan Qaboos University Hospital (SQUH) were reviewed.

RESULTS

A total of 32 patients were diagnosed with CGD using molecular studies. Genetically confirmed individuals included 1 patient with XL-CGD (a large deletion involving the CYBB and XK genes resulting in a McLeod phenotype), 27 patients with AR-CGD with a c.579G>A (p.Trp193X) mutation at the NCF1 gene, and 4 patients with AR-CGD with a c.784G>A (p.Gly262Ser) mutation at the NCF1 gene. Flow cytometry and molecular results were available for comparison in 26 patients with AR-CGD. The patients with AR-CGD had a range of flow cytometry-generated fluorescent patterns as follows: reduced neutrophil stimulation with a sharp peak (12/26), reduced neutrophil stimulation with a broad peak (11/26), and a complete lack of neutrophil stimulation (3/26). No consistent flow cytometry-generated fluorescent pattern was observed in either of the 2 AR mutations identified in our patients.

CONCLUSION

Flow cytometry is a robust test of CGD diagnosis. However, results should be interpreted with caution when predicting the underlying probable genotype, and results need to be complemented with definitive molecular studies.

CD34+CD38-CD123+ Cells Are Present in Virtually All Acute Myeloid Leukaemia Blasts: A Promising Single Unique Phenotype for Minimal Residual Disease Detection

BACKGROUND/AIMS

In CD34-positive acute myeloid leukaemia (AML), the leukaemia-initiating event likely takes place in the CD34+CD38- cell compartment. CD123 has been shown to be a unique marker of leukaemic stem cells within the CD34+CD38- compartment. The aim of this study was to identify the percentage of CD34+CD38-CD123+ cells in AML blasts, AML CD34+CD38- stem cells, and normal and regenerating bone marrow CD34+CD38- stem cells from non-myeloid malignancies.

METHODS

Thirty-eight adult de novo AML patients with intention to treat were enrolled after the application of inclusion criteria from February 2012 to February 2017. The percentage of the CD34+CD38-CD123+ phenotype in the blast population at diagnosis was determined using a CD45-gating strategy and CD34+ backgating by flow cytometry. We studied the CD34+CD38-CD123+ fraction in AML blasts at diagnosis, and its utility as a unique phenotype for minimal residual disease (MRD) of AML patients.

RESULTS

CD123+ cells were present in 97% of AML blasts in patients at diagnosis (median 90%; range 21-99%). CD123+ cells were also present in 97% of the CD34+CD38- compartment (median 0.8164%, range 0.0262-39.7%). Interestingly, CD123 was not present in normal and regenerating CD34+CD38- bone marrow stem cells (range 0.002- 0.067 and 0.004-0.086, respectively).

CONCLUSION

The CD34+CD38-CD123+ phenotype is present in virtually all AML blasts and it may be used as a unique single phenotype for MRD detection in AML patients.

Clinical and molecular findings of chronic granulomatous disease in Oman: family studies

Chronic granulomatous disease (CGD), a rare inherited disorder of the innate immune system, results from mutations in any one of the five genes encoding the subunits of the nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase enzyme, and is characterized by recurrent life-threatening bacterial and fungal infections. Molecular analysis of 14 Omani CGD patients from 10 families, diagnosed to have CGD on clinical (recurrent infections) and biochemical grounds (positive for both the nitroblue tetrazolium (NBT) test and the dihydrorhodamine (DHR-1,2,3 assay), revealed that only one patient had X-linked CGD, with a large deletion involving both the gp91-phox gene (CYBB) and the McLeod gene (XK). The remaining 13 patients were all homozygotes from a previously described c.579G>A (p.Trp193X) mutation in the NCF1 gene on chromosome 7, responsible for autosomal recessive CGD (AR-CGD). Although X-linked CGD is the most common type of CGD disorder in most population groups, AR-CGD is the most prevalent type in Oman.

Neonatal Screening: Mean haemoglobin and red cell indices in cord blood from Omani neonates

OBJECTIVES

The aim of this study was to validate the interpretation of red blood cell indices in complete blood count (CBC) and high performance liquid chromatography (HPLC) results on cord blood samples in consecutive Omani neonates.

METHODS

Cord blood samples from 7,837 neonates, were analysed with CBC and HPLC using the β-thalassaemia short programme. Direct sequencing of abnormal samples with HbS, HbD, HbE and HbC was performed to validate the HPLC results. Additionally, in cases with HbA β10%, the β-globin gene was directly sequenced for β-thalassaemia mutation analysis.

RESULTS

Overall, 4,042 subjects (51.58%) had normal HPLC (HbA 22.88±8.03; HbF 77.02±8.04), whereas the presence of Hb Barts in the remaining 3,795 cases (48.42%) indicated the presence of α-thalassaemia. No case of HbH was detected. In the former subgroup respectively, the mean Hb (15.38±2.04 g/dl) red blood cell (RBC) count (4.69±0.68 × 10(12)/l), Hct (50.5±7.18%), mean corpuscular volume (MCV) (107.66±7.75 fl), mean corpuscular haemoglobin (MCH) (33.31±4.07 pg), mean corpuscular haemoglobin concentration (MCHC) (30.98±3.44 g/dl), red cell distribution width (RDW) (17.01±2.17%) whereas, in the latter group with α-thalassaemia, it was (14.79±2.90 g/dl); (5.09±0.77 × 10(12)/l); (49.7±7.40%); (97.29±13.8 fl); (29.74±11.80 pg); (30.39±3.6 g/dl), and (18.09±2.56%) respectively. DNA sequencing of samples with abnormal haemoglobin could validate the CBC and HLPC interpretations in all cases.

CONCLUSION

This is the first study comparing the hemoglobin and red cell indices in the cord blood from newborn Omani subjects with those from other countries in the region, showing comparable results to those seen in Saudi neonates. The study also validates the CBC and HPLC interpretations of the cord blood red cell indices in the Omani neonate. The incidence of α-thalassaemia diagnosed by the presence of Hb Barts in cord blood of neonates was 48.42%.