Aims Mitogen-activated protein kinase (MAPK) pathway alteration is a major oncogenic driver in paediatric low-grade gliomas (LGG) and some adult gliomas, encompassing BRAF (most common) and non-BRAF alterations. The aim was to determine the frequency, molecular spectrum and clinicopathological features of MAPK-altered gliomas in paediatric and adult patients at our neuropathology site in Kuwait. Methods We retrospectively searched the data of molecularly sequenced gliomas between 2018 and 2023 for MAPK alterations, revised the pathology in view of the 2021 WHO classification and evaluated the clinicopathological data for possible correlations. Results Of 272 gliomas, 40 (15%) harboured a MAPK pathway alteration in 19 paediatric (median 9.6 years; 1.2–17.6) and 21 adult patients (median 37 years; 18.9–89.2), comprising 42% and 9% of paediatric and adult cases, respectively. Pilocytic astrocytoma and glioblastoma were the most frequent diagnoses in children (47%) and adults (43%), respectively. BRAF V600E (n=17, 43%) showed a wide distribution across age groups, locations and pathological diagnoses while KIAA1549::BRAF fusion (n=8, 20%) was spatially and histologically restricted to cerebellar paediatric LGGs. Non-V600E variants and BRAF amplifications accompanied other molecular aberrations in high-grade tumours. Non-BRAF MAPK alterations (n=8) included mutations and gene fusions involving FGFR1, NTRK2, NF1, ROS1 and MYB. Fusions included KANK1::NTRK2, GOPC::ROS1 (both infant hemispheric gliomas), FGFR1::TACC1 (diffuse LGG), MYB::QKI (angiocentric glioma) and BCR::NTRK2 (glioblastoma). Paradoxical H3 K27M/MAPK co-mutations were observed in two LGGs. Conclusion The study provided insights into MAPK-altered gliomas in Kuwait highlighting the differences among paediatric and adult patients and providing a framework for planning therapeutic polices.

Kuwait is a small Arabian Gulf country with a high rate of consanguinity and where a national newborn screening program was expanded in October 2014 to include a wide range of endocrine and metabolic disorders. A retrospective study conducted between January 2015 and December 2020 revealed a total of 304,086 newborns have been screened in Kuwait. Six newborns were diagnosed with classic homocystinuria with an incidence of 1:50,000, which is not as high as in Qatar but higher than the global incidence. Molecular testing for five of them has revealed three previously reported pathogenic variants in the CBS gene, c.969G>A, p.(Trp323Ter); c.982G>A, p.(Asp328Asn); and the Qatari founder variant c.1006C>T, p.(Arg336Cys). This is the first study to review the screening of newborns in Kuwait for classic homocystinuria, starting with the detection of elevated blood methionine and providing a follow-up strategy for positive results, including plasma total homocysteine and amino acid analyses. Further, we have demonstrated an increase in the specificity of the current newborn screening test for classic homocystinuria by including the methionine to phenylalanine ratio along with the elevated methionine blood levels in first-tier testing. Here, we provide evidence that the newborn screening in Kuwait has led to the early detection of classic homocystinuria cases and enabled the affected individuals to lead active and productive lives.

In gastrointestinal stromal tumors (GISTs), identifying prototypical mutations in the KIT/PDGFRA oncogenes, or in rare alternate genes, is essential for prognostication and predicting response to tyrosine kinase inhibitors. Conversely, wild-type GISTs (WT-GIST), which lack known mutations, have limited treatment options. Data on the mutational landscape of GISTs and their impact on disease progression are very limited in Kuwait. Using a targeted next-generation sequencing panel, we investigated the spectrum and frequency of KIT, PDGFRA, and RAS-pathway-related mutations in 95 out of 200 GISTs diagnosed at Kuwait Cancer Center from 2005 to 2023 and assessed their correlation with clinicopathological parameters. Among the 200 tumors (median age 55 years; 15–91), 54% originated in the stomach, 33% in the small bowel, 7% in the colorectum, 1.5% in the peritoneum, and 4.5% had an unknown primary site. Of the 95 molecularly profiled cases, 88% had a mutation: KIT (61%), PDGFRA (25%), NF1 (2%), and one NTRK1 rearrangement. Ten WT-GISTs were identified (stomach = 6, small bowel = 2, and colorectum = 2). WT-GISTs tended to be smaller (median 4.0 cm; 0.5–8.0) (p = 0.018), with mitosis ≤5/5 mm², and were of lower risk (p = 0.019). KIT mutations were an adverse indicator of disease progression (p = 0.049), while wild-type status did not significantly impact progression (p = 0.934). The genetic landscape in this cohort mirrors that of global studies, but regional collaborations are needed to correlate outcomes with genetic variants.

Background: Ewing sarcoma (ES) is a rare, aggressive small round cell sarcoma (SRCS) that peaks in adolescence. Given its rarity, atypical age or site presentations increase the risk of misclassification. This study examines age-related clinicopathological patterns in molecularly confirmed canonical ES (FET::ETS-fused). Methods: Between 2016 and 2025, 90 tumors diagnosed as ES or Ewing-like SRCSs underwent targeted RNA sequencing and/or EWSR1 break-apart fluorescence in situ hybridization. Patients were stratified into three age groups: 0–18, 19–39, and ≥40 years. Clinical, anatomical, pathological, molecular, and treatment/outcome variables were compared across strata. Results: Canonical ES accounted for 84% (76/90) of SRCSs, dominated by EWSR1::FLI1 (89%). ES comprised 91% of SRCSs in children but declined to 75% in older adults. Tumors arose mainly in bone (63%), with a significant age association (p = 0.016): children and young adults were primarily skeletal (73% and 62%), whereas older adults were predominantly extraskeletal (78%). Renal ES clustered in adults ≥40 years (p = 0.003). Classic histology predominated; atypical patterns were more common in extraskeletal tumors but lacked age specificity. Ewing-like SRCSs (n = 14), with heterogeneous or absent fusions, displayed a broader age distribution—including infants and older adults—and a marked extraskeletal predominance (86%, p = 0.001). Metastatic presentation strongly predicted inferior survival (p = 0.025). Treatment was multimodal, with neoadjuvant chemotherapy more frequent in children (90%, p = 0.029). Conclusions: Age significantly influences anatomic presentation and certain treatment choices in ES, whereas histology and survival remain broadly similar across groups. Age-linked extraskeletal trends reinforce the importance of routine molecular testing, particularly in underreported Middle Eastern populations.

Newborn screening for very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency in Kuwait was initiated in October 2014. Over a 7-year period (January 2015 to December 2021), 43 newborns were diagnosed with VLCAD deficiency out of 356,819 screened, corresponding to an incidence of 1:8290 and 1:5405 among only Kuwaiti newborns. This study represents the first comprehensive review of newborn screening for VLCAD deficiency in Kuwait. The screening process begins with the detection of elevated blood C14:1 levels in dried blood spots, followed by confirmatory testing using dried blood spots acylcarnitine profiling, with or without molecular testing. Furthermore, this study demonstrates that incorporating the C14:1/C2 ratio as a supplementary marker in first-tier testing alongside C14:1 improves the positive predictive value (PPV) of the current newborn screening for VLCAD deficiency. Adding molecular genetic testing for known VLCAD variants as a second-tier strategy to the national program is also recommended to further enhance specificity and improve PPV. Our findings provide evidence that the expanded newborn screening program in Kuwait has successfully facilitated the early detection of VLCAD deficiency, preventing death and disability in affected infants.

Background: Real-world data examining structured modality selection for mediastinal/hilar adenopathy in mixed malignant and benign cohorts is limited. We evaluated the performance of a multidisciplinary team (MDT)-guided strategy incorporating EBUS/EUS-B and EUS for both benign and malignant disease. Methods: We conducted a retrospective study, including consecutive adults undergoing mediastinal/hilar lymph node sampling by endoscopy after MDT discussion. All cases were discussed at a dedicated thoracic MDT before the procedure, where the indication for sampling and the modality were predetermined based on anatomic accessibility on CT/PET-CT, clinical data, and anticipated tissue requirements. The primary outcome was diagnostic yield, defined as the proportion of procedures providing a definitive pathologic diagnosis consistent with the clinical and radiologic context, with concordance for benign diagnoses confirmed by a minimum of 3 months of clinical and radiologic follow-up. Secondary outcomes included yield by indication, modality, and adequacy of molecular testing. Results: Among 213 patients (64.3% male; mean age 56±14.5 y), the overall diagnostic yield was 92%. Indications for biopsy comprised 134 suspected carcinomas and 79 suspected benign or lymphoproliferative cases. Diagnostic yield was 91.8% (n=123/134) in suspected carcinoma and 92.4% (n=73/79) in suspected benign or lymphoproliferative disease. Molecular testing was processed in 57 malignant cases, with 89.5% successful completion. Conclusion: A structured, MDT-driven endosonographic strategy was associated with high diagnostic and molecular adequacy in this cohort of malignant and benign mediastinal/hilar lymphadenopathy. Given the nonrandomized design and small sample size, findings should be interpreted cautiously. Prospective studies are warranted to further define the optimal role of each modality.