Search Results (100)

Cholangiocarcinoma (CCA) is an aggressive and molecularly heterogeneous malignancy characterized by a profoundly immunosuppressive tumor microenvironment (TME) and historically limited therapeutic options. Recent advances have redefined the treatment paradigm, with phase III trials establishing chemoimmunotherapy as a standard of care and multi-omic profiling elucidating the interplay between tumor genomics, stromal architecture, and immune regulation. Despite these gains, durable clinical benefit remains confined to a minority of patients, reflecting convergent mechanisms of primary and acquired resistance—including immune exclusion, myeloid-dominant suppression, and genotype-driven “cold” tumor states. In this review, we synthesize emerging insights into the immune landscape of CCA, integrating data from single-cell, spatial, and translational studies to define the cellular and molecular circuits governing immune evasion. Beyond canonical biomarkers such as mismatch repair and microsatellite status, we highlight how spatial organization of immunity—in particular, tertiary lymphoid structures, dynamic myeloid and stromal interactions, and pathway-level features—shape immunotherapy responsiveness. We also examine how tumor-intrinsic alterations, including IDH1 mutation, FGFR2 fusions, KRAS activation, and MTAP loss, define distinct immunologic phenotypes with direct implications for immunotherapeutic response and biomarker-driven patient selection. We evaluate the expanding clinical trial landscape of immunotherapy in CCA and more broadly in BTC, including adoptive cell therapies and cancer vaccines. Together, these advances position CCA as a paradigm of how tumor genotype and microenvironment co-evolve to define immunotherapy sensitivity and resistance. Full article

Fibroblast growth factor receptor 2 (FGFR2) inhibitors such as pemigatinib are targeted therapies for cholangiocarcinoma with FGFR2 alterations. While generally well tolerated, they are associated with unique adverse events. Calciphylaxis, a potentially fatal vascular calcification disorder, is a rare complication. We present a 43-year-old woman with metastatic intrahepatic cholangiocarcinoma harboring an FGFR2 fusion who developed calciphylaxis after seven months of pemigatinib therapy. Despite drug discontinuation, antibiotics, and multidisciplinary supportive care, she deteriorated rapidly and died from sepsis and advanced disease. Histopathological analysis confirmed dermal and vascular calcifications consistent with calciphylaxis. This case highlights the importance of early recognition of cutaneous lesions in patients on FGFR inhibitors. Prompt cessation of therapy, management of metabolic derangements, and consideration of sodium thiosulfate may be lifesaving. Full article

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy, with rising incidence and a 5-year survival rate of 13%. Late presentation, early metastasis, and intrinsic resistance constrain the efficacy of cytotoxic chemotherapy, which remains the backbone of PDAC treatment, with only modest survival gains and resistance nearly universal. Although KRAS mutations dominate tumour biology (~90% of cases), PDAC is a heterogeneous disease with distinct molecular subtypes that confer differential therapeutic vulnerabilities. Advances in comprehensive molecular profiling have catalysed a paradigm shift toward precision oncology in PDAC. In KRAS-mutant PDAC, mutation-specific inhibitors have established proof-of-concept, particularly in KRAS G12C disease, while next-generation approaches including KRAS G12D inhibitors, RAS-“ON” inhibitors, proteolysis-targeting chimeras (PROTACs), and KRAS-targeted vaccine strategies are expanding the therapeutic landscape. Combination strategies targeting upstream and downstream effectors of the RAS–MAPK pathway are also being explored to enhance the depth and durability of response. In parallel, KRAS-wild-type PDAC has emerged as a molecularly distinct subgroup enriched for rare but actionable alternative oncogenic fusion drivers including NRG1, NTRK, RET, ALK, and FGFR. Additional molecularly directed strategies targeting HER2 alterations, BRAF mutations, EGFR-dependent signalling, and tumour-selectively exposed surface antigens such as CLDN18.2 are under investigation across PDAC irrespective of KRAS mutation status. Synthetic lethal approaches, including targeting the PRMT5/CDKN2A/MTAP axis, represent a further emerging therapeutic strategy. Germline homologous recombination repair defects, particularly involving BRCA1/2 and PALB2, further define clinically important subsets with sensitivity to platinum chemotherapy and PARP inhibition. This review summarises current and emerging targeted and molecularly directed therapeutic strategies in PDAC, emphasising the importance of molecular stratification and recent advances shaping precision oncology in this historically treatment-refractory disease. Full article

Pancreatic ductal adenocarcinoma (PDAC) and biliary tract cancers (BTCs) remain highly lethal gastrointestinal malignancies because of late presentation, marked molecular heterogeneity, and limited durable benefit from conventional systemic therapy. This narrative review summarizes recent advances in both diseases, focusing on practice-informing clinical trials, biomarker-driven treatment strategies, and translational insights into tumor biology and resistance. In PDAC, progress includes refinement of perioperative management, broader germline and somatic testing, recognition of DNA damage repair-deficient subsets, and development of KRAS-directed therapies and rational combination strategies. In BTCs, especially intrahepatic cholangiocarcinoma, comprehensive molecular profiling has expanded precision oncology through actionable alterations such as FGFR2 rearrangements, IDH1 mutations, HER2 amplification/overexpression, BRAF V600E, NTRK fusions, and MSI-high/dMMR status. Immunotherapy has a clearer role in selected BTC populations, whereas in PDAC benefit remains largely restricted to rare biomarker-defined subsets. Across both diseases, circulating tumor DNA is emerging as a promising tool for prognostication, minimal residual disease assessment, response monitoring, and early resistance detection. Contemporary care increasingly depends on early molecular profiling, individualized treatment sequencing, and integration of targeted therapies, biomarker-guided immunotherapy, and clinical trials. Full article

Background: Achondroplasia, the most common genetic dwarfism caused by the FGFR3 mutation (autosomal dominant, 80% de novo), results in a disproportionately short stature. Thoracolumbar kyphosis (TLK), combined with characteristic spinal canal stenosis, increases the risk of symptomatic compression, yet the literature lacks clear thresholds for symptom onset or progressive deformity angles. Methods: A 16-year-old female with achondroplasia presented with rapidly progressive kyphosis despite conservative management (bracing and therapy). Over six months, she developed neurogenic claudication; bilateral leg pain; weakness; and paresthesia that worsened with standing/walking, which was relieved by flexion/sitting. Imaging demonstrated surgical-threshold kyphosis with progressive spinal misalignment. Her symptoms indicated compressive myeloradiculopathy from lumbar stenosis, critical given achondroplasia’s congenitally narrowed canal and heightened neurologic vulnerability. Results: Staged surgery planned: Posterior fusion T6-L4 with pedicle screws and then extensive decompression (laminectomy/foraminotomy T11-L3), L1 corpectomy with expandable titanium cage, and Ponte osteotomies. Intraoperative complications included a malpositioned left T10 screw breaching the anterior/lateral cortex near the aorta, requiring urgent revision. Postoperatively: Neurogenic bladder, wound leakage, and E. coli urinary tract infection (UTI) with fever (treated with IV antibiotics). After infection resolution, definitive surgery removed the malpositioned screw and completed decompression, corpectomy, cage placement, bone grafting, and osteotomies, successfully resolving neurological symptoms. However, 13 cm trunk lengthening caused severe functional impairment—disproportionately short arms prevented independent toileting and dressing. Left arm lengthening via external fixation restored partial function. At 2.5-year follow-up, there was solid fusion, no neurological deficits, and improved quality of life. Conclusions: Surgery addresses severe TLK, vertebral wedging, and neurogenic claudication in achondroplasia. Vertebral column resection effectively corrects TLK and neurological deficits but carries a high complication risk. This should be reserved for severe TLK with hypoplastic vertebrae, performed by experienced surgeons. Critically, correction magnitude must preserve limb–trunk proportions to prevent functional disability, as excessive lengthening may necessitate additional limb procedures for independence restoration. Full article

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a rare lung malignancy characterized by an aggressive clinical course and an unfavorable prognosis. Next-generation sequencing (NGS) has revealed that LCNECs exhibit molecular features resembling either small-cell lung carcinoma (SCLC-like LCNEC) or non-small cell lung carcinoma (NSCLC-like LCNEC). This study aimed to characterize the incidence of actionable gene variants in a retrospective cohort of LCNEC patients using a targeted NGS approach. Microscopic diagnosis was established according to the 2021 World Health Organization (WHO) classification using a standard immunohistochemical (IHC) panel. In total, 216 LCNEC tumor samples were analyzed for molecular variants in 17 genes using the RNA-based Archer FusionPlex Lung NGS assay (Integrated DNA Technologies, USA) and the MiSeq platform (Illumina, USA)—an algorithm utilized for routine NSCLC diagnosis. Overall, 46 variants were identified in 46/216 (21.3%) tumor samples, with 28/216 (13%) LCNECs harboring at least one actionable molecular variant potentially targetable by registered or investigational agents. KRAS variants (5%; including G12C at 2%) and PIK3CA variants (5%) were the most prevalent, followed by RET single-nucleotide variants (3%), uncommon EGFR variants (1%), and BRAF class II and III variants (<1%). Notably, no classical EGFR exon 18–21 mutations nor ALK, FGFR1/2/3, or ROS1 alterations (mutations or fusions) were detected, despite the technical capability of the assay to identify such variants. A novel in-frame gene fusion (TMEM79::NTRK1) was identified in a single tumor sample (0.5%). Our results confirm that LCNECs harbor potentially targetable alterations in KRAS, PIK3CA, RET, BRAF, and NTRK1, albeit at lower frequencies than those typically observed in NSCLC. Full article

From an epidemiological perspective, polymorphous low-grade neuroepithelial tumor (PLNTY) represents a small proportion of brain tumors encountered in epilepsy surgery series. Their rarity and relatively recent recognition likely contribute to underdiagnosis and poor prognosis. In terms of histopathological features, they are similar to oligodendrogliomas. Molecular analyses can be used to show the fusion between fibroblast growth factor receptor (FGFR3) and transforming acidic coiled coil (TACC) proteins, which most commonly results in progression towards glioblastoma (GBM). We report a case of a 62-year-old man who underwent left frontal craniotomy to remove a frontal mass. Histologically, the glial lesion consisted of elements associated with oligodendroglia-like features. Immunohistochemistry was positive for glial fibrillary acidic protein (GFAP), oligodendrocyte transcription factor 2 (OLIG2), and α-thalassemia X-linked mental retardation syndrome (ATRX) nuclear expression, but negative for isocitrate dehydrogenase 1 (IDH1) and BRAF-V600E. Next-generation sequencing showed the FGFR-TACC3 fusion, and taken together, these findings supported the final diagnosis of PLNTY. During follow-up, the patient underwent a second neurosurgery, where histological evaluation indicated a GMB. This article presents clinical and radiological data, morphology, immunohistochemistry, molecular features, and treatment to enhance the clinical and pathological understanding of PLNTY with FGFR3-TACC3 fusion for all professionals involved in medical decisions. Full article

Rhabdomyosarcoma is a small round-cell soft tissue tumor that occurs mainly in pediatric and adolescent/young adult (AYA) patients but also rarely in adults. Multidisciplinary treatments including multidrug therapy and local therapy (surgery and/or radiation) are the current standard of care, and treatment strategies are determined according to the estimated risk based on the patient’s age, site of onset, and histologic type, as well as the disease stage. New treatment developments in recent years have been based on risk; lower cumulative doses of alkylating agents to reduce late toxicity for low-risk patients are being studied, and long-term maintenance therapy or the addition of new drugs inhibitors to standard multidisciplinary therapy for intermediate- to high-risk patients have been investigated. For high-risk and metastatic patients, novel molecular targeted drug candidates are being evaluated. The target candidates for rhabdomyosarcoma have included the RAS-signaling pathway, ALK, NTRK, FGFR, and MSI-High. In addition, fusion genes (e.g., PAX3/7-FOXO1), which play an important role in diagnostic and prognostic factors, are also being investigated as potential therapeutic targets as their underlying backgrounds are gradually becoming clear. This review summarizes the overall picture of the development of novel therapies for rhabdomyosarcoma and discusses the direction that should be taken in the future. Full article

Fibroblast growth factor receptor 2 (FGFR2) rearrangements represent one of the most actionable molecular alterations in biliary tract cancer, particularly in intrahepatic cholangiocarcinoma (iCCA). Approximately 10–16% of iCCA cases harbor FGFR2 fusions or rearrangements, defining a distinct molecular subtype characterized by sensitivity to FGFR-targeted therapies. Selective FGFR tyrosine kinase inhibitors, including the reversible inhibitor pemigatinib and the irreversible inhibitor futibatinib, have demonstrated clinically meaningful response rates and durable disease control in patients with previously treated FGFR2-altered iCCA, leading to regulatory approvals and the incorporation of FGFR inhibition into contemporary treatment paradigms. However, the development of acquired resistance—most commonly driven by secondary kinase-domain mutations and activation of bypass signaling pathways—remains a major limitation to sustained therapeutic benefit. This review summarizes the biological basis of FGFR2 alterations, highlights current clinical evidence supporting FGFR inhibition, and discusses the evolving landscape of resistance mechanisms. We further examine emerging therapeutic strategies aimed at overcoming resistance, including next-generation FGFR inhibitors and rational combination approaches. In addition, we highlight the growing role of circulating tumor DNA as a noninvasive tool for longitudinal molecular monitoring and treatment guidance. Together, these insights underscore the central role of FGFR2-directed therapy in precision oncology for biliary tract cancer and provide a framework for optimizing and extending targeted treatment in this molecularly defined disease subset. Full article

Thalamic gliomas are among the most challenging pediatric brain tumors due to the delicate functions of the thalamus. Limited surgical intervention leads to the use of adjuvant therapies, including targeted therapy. Thalamic gliomas can be divided into two distinct groups: diffuse midline glioma (DMG) and low-grade glioma (LGG). The most common mutations that can be targeted for treatment are the KIAA1549-BRAF fusion; BRAF V600E mutation; EGFR, FGFR, PDGFR, NTRK, and CDK4/6 mutations; other MAP kinase pathway alterations; and PI3K/AKT/mTOR activation. The bithalamic high-grade glioma especially demonstrates EGFR mutations which makes it a distinct entity. Targeted therapy, including tyrosine kinas inhibitors has been shown to improve the overall survival compared to conventional therapy in certain situations. Demonstrating the mutation carried by the tumor is very critical in this regard. The purpose of this article is to focus on the treatment of thalamic glioma in pediatric patients in light of molecular information. Full article

Aberrations in fibroblast growth factor receptors (FGFRs) constitute a key oncogenic mechanism across multiple solid tumors, influencing tumor initiation, therapeutic response, and clinical outcomes. This review synthesizes current knowledge on the molecular biology, signaling networks, and tumor-specific distribution of FGFR alterations, including amplifications, point mutations, and gene fusions. The mechanistic basis of FGFR-driven tumor progression is discussed, including activation of downstream signaling pathways, crosstalk with other receptor tyrosine kinases, and regulation of the tumor microenvironment, angiogenesis, and immune escape. Recent development of selective FGFR inhibitors—such as pemigatinib, erdafitinib, and futibatinib—has translated mechanistic insights into measurable clinical benefits in genomically defined patient populations. However, acquired resistance remains a major challenge, driven by secondary mutations, activation of bypass pathways, and intratumoral heterogeneity. Integration of multi-omics profiling, liquid biopsy monitoring, and biomarker-guided patient selection is essential to optimize therapeutic efficacy and overcome resistance. This review also highlights emerging therapeutic modalities, such as antibody–drug conjugates and nanotechnology-based delivery systems, which may improve target specificity and prolong therapeutic durability. By integrating molecular, translational, and clinical evidence, this review aims to establish a comprehensive framework for precision oncology strategies targeting FGFR-driven malignancies. Full article

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with a five-year survival rate of 3–15% and limited effective treatment options for most patients. Approximately 5–10% of cases are wild-type KRAS and are more likely to harbor rare alterations, including gene fusions involving anaplastic lymphoma kinase (ALK), ROS Proto-Oncogene 1 (ROS1), neurotrophic tyrosine receptor kinase (NTRK), Rearranged During Transfection (RET), Fibroblast Growth Factor Receptor (FGFR), or Neuregulin 1 (NRG1) genes, as well as germline mutations in DNA repair genes. This review integrates current evidence on the prevalence, molecular profile, and clinical significance of gene fusions, amplification, and somatic/germline mutations in PDAC, with a particular focus on the wild-type KRAS subgroup. Clinical trial data and case reports indicate that these alterations can enhance patient susceptibility to targeted therapies. Currently, selpercatinib, larotrectinib, and repotrectinib are approved by the FDA for the treatment of certain solid tumors harboring specific gene fusions. Recent studies on zenocutuzumab resulted in the FDA-accelerated approval for NGR1 fusion-positive NSCLC and PDAC. Germline mutations may specifically increase responsiveness to poly(ADP-ribose) polymerase (PARP) inhibitors or platinum-based treatments. Comprehensive genomic profiling, incorporating fusion detection and germline testing, is essential to identify patients who may benefit from precision-based approaches. Full article

Background/Objectives: Lung cancer remains among the most frequently diagnosed malignancies in Romania, with a high mortality rate. Beyond EGFR mutations, clinically relevant genetic alterations in non-small cell lung cancer (NSCLC) include fusions involving ALK, ROS1, RET, and NTRK1/2/3. This study aimed to determine the prevalence of these mutations in a Romanian cohort and evaluate their associations with clinicopathological features. Methods: DNA and RNA were simultaneously extracted from formalin-fixed, paraffin-embedded (FFPE) tissue sections using the Genexus Purification System (ThermoFisher Scientific). Concentrations were quantified fluorometrically, and gene fusions were analyzed with Ion Torrent NGS (Ion GeneStudio S5) with the Oncomine Focus Assay (ThermoFisher Scientific). Library preparation was automated with the Ion Chef System, and data interpretation was conducted using Ion Reporter. Results: Among 721 newly diagnosed NSCLC patients, 28 (3.88%) harbored gene fusions. Adenocarcinoma prevailed among fusion-positive cases (85.7%). The subgroup included 15 males and 13 females, with a mean age of 63.25 years (range 43–83). ALK fusions were most frequent (1.66% of the cohort; 42.86% of positives), predominantly EML4::ALK. ROS1 fusions were detected in five patients (0.7%), most frequently CD74::ROS1. RET fusions occurred in 1.11%. Rare fusions included one ETV6::NTRK3, one PTPRZ1::MET, and one FGFR3::TACC3 co-occurring with EGFR L858R. Conclusions: Gene fusions were present in a minority of NSCLC cases, with ALK, ROS1, and RET being the most clinically relevant. These alterations were mutually exclusive with common drivers such as EGFR or KRAS. Detection of rare fusions highlights the therapeutic potential of comprehensive NGS profiling in Romanian NSCLC patients. Full article

Genetic abnormalities of the fibroblast growth factor receptor 2 (FGFR2) gene, including amplification, fusions, and mutations, have been reported in various solid tumors. While molecular targeted therapies against FGFR2 fusion have been proved to be useful in cholangiocarcinoma, the therapeutic significance of FGFR2 inhibitors remains unclear in other various solid cancers. Genomic and clinical information from solid tumor cancer gene panel testing cases is consolidated in the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database in Japan. This study aimed to utilize the C-CAT database to clarify the clinical–pathological significance of FGFR2 abnormalities. A total of 101,231 patients with solid cancer have been registered in the C-CAT database between June 2019 and June 2025. Of the 101,231 cases, 1312 cases with FGFR2 gene abnormalities were analyzed. FGFR2 alterations included amplification in 515 cases, fusion in 280 cases, and mutations in 568 cases. They were detected most frequently in the biliary tract (271 cases), esophagus/stomach (231 cases), and breast (211 cases). Amplification was frequent in the esophagus/stomach (205 cases) and breast (105 cases). Mutations were frequent in the uterus (111 cases), breast (89 cases), and biliary tract (86 cases). Among 515 FGFR2 alteration cases, FGFR2 inhibitors were administered in 85 cases. Of the 85 cases, disease control was achieved in 49 cases, 44 cases of which were biliary tract cancer. FGFR2 might be a promising therapeutic target not only for cholangiocarcinoma with fusion but also for esophagus/stomach cancer and breast cancer with FGFR2 alterations. Full article

Introduction: Gastrointestinal stromal tumors (GISTs) are primarily driven by mutations in KIT (KIT proto-oncogene receptor tyrosine kinase) or PDGFRA (platelet-derived growth factor receptor alpha), but resistance to tyrosine kinase inhibitors (TKIs) such as imatinib remains a major clinical challenge. Alterations in fibroblast growth factor receptor 2 (FGFR2), although rare, are emerging as important contributors to tumor progression and drug resistance. This review evaluates the molecular mechanisms, expression profiles, detection methods, and therapeutic implications of FGFR2 in GIST. Methods: We searched PubMed, Web of Science, Google Scholar, and ClinicalTrials.gov for studies published between January 2010 and June 2025, using combinations of keywords related to FGFR2, gastrointestinal stromal tumor, resistance mechanisms, gene fusion, amplification, polymorphisms, and targeted therapy. Eligible studies were critically assessed to distinguish GIST-specific data from evidence extrapolated from other cancers. Results:FGFR2 is expressed in multiple normal tissues and at variable levels in mesenchymal-derived tumors, including GIST. Its alterations occur in approximately 1–2% of GIST cases, most commonly as gene fusions (e.g., FGFR2::TACC2, <1%) or amplifications (1–2%); point mutations and clinically significant polymorphisms are extremely rare. These alterations activate the MAPK/ERK and PI3K/AKT pathways, contribute to bypass signaling, and enhance DNA damage repair, thereby promoting TKI resistance. Beyond mutations, mechanisms such as amplification, ligand overexpression, and microenvironmental interactions also play roles. FGFR2 alterations appear mutually exclusive with KIT/PDGFRA mutations but occasional co-occurrence has been reported. Current clinical evidence is largely limited to small cohorts, basket trials, or case reports. Conclusions:FGFR2 is an emerging oncogenic driver and biomarker of resistance in a rare subset of GISTs. Although direct evidence remains limited, particularly regarding DNA repair and polymorphisms, FGFR2-targeted therapies (e.g., erdafitinib, pemigatinib) show potential, especially in combination with TKIs or DNA-damaging agents. Future research should prioritize GIST-specific clinical trials, the development of FGFR2-driven models, and standardized molecular diagnostics to validate FGFR2 as a therapeutic target. Full article