NTRK fusion

First-generation tyrosine kinase inhibitors (TKIs) such as crizotinib displayed significant early reactions but faced challenges due to restricted central nervous system (CNS) penetration and mutation resistance, while entrectinib and larotrectinib expanded treatment options but also experienced resistance...Safety data shows an acceptable toxicity profile, mainly featuring gastrointestinal and hepatic adverse effects, with fewer neurocognitive side effects compared to lorlatinib...Current trials and regulatory activities in China, the U.S., and other locations demonstrate taletrectinib's growing clinical significance. Taletrectinib's well-rounded pharmacological attributes of systemic action, intracranial effectiveness, resistance range, and tolerability render it an intriguing enhancement to the framework of precision oncology.

Dabrafenib plus trametinib has shown superiority over chemotherapy in pediatric low-grade gliomas and activity against high-grade diseases. Larotrectinib and entrectinib provide tumor-agnostic options for NTRK-fusion-positive tumors with central nervous system penetration. Selumetinib offers clinical benefits in NF1-associated plexiform neurofibromas and shows promise for treating NF1-related low-grade gliomas. Tovorafenib, a type II RAF inhibitor active in BRAF-altered tumors (including BRAFKIAA1549 fusion), achieved robust responses, thereby leading to FDA approval. ONC201 (dordaviprone) has received accelerated approval for the treatment of H3 K27M-mutant diffuse midline gliomas, with Japanese trials and patient-initiated programs expanding access. Abemaciclib, a CDK4/6 inhibitor, is under phase II evaluation for pediatric high-grade glioma and diffuse midline glioma, including sites in Japan. Neurosurgeons play a pivotal role in securing high-quality biopsies, thus enabling comprehensive molecular diagnostics and facilitating enrollment in international trials. This review summarizes current targeted therapies and ongoing studies and outlines practical considerations for integrating precision oncology into pediatric neuro-oncology in Japan.

This case underscores the importance of integrating molecular diagnostics into the evaluation of atypical spindle cell tumors, particularly those presenting with aggressive clinical features despite low-grade histology. Early identification of NTRK fusions enables timely initiation of TRK inhibitor therapy, offering durable disease control and functional recovery. Broader awareness and implementation of molecular testing can greatly enhance the management of rare pediatric sarcomas.

In children with NTRK fusion-positive sarcomas, upfront TRK inhibition yielded faster, deeper responses and eliminated mutilating surgery in our cohort. These data support TRK inhibitors as preferred neoadjuvant options, particularly to facilitate non-morbid resections and to avoid functional disability.

Further in vivo assay displayed that 20 effectively inhibited tumor growth with no apparent toxicity in the Ba/F3-LMNA-NTRK1G667C xenograft model. Overall, these findings indicated that, unlike conventional inhibitors, such bifunctional agents represent the first class of monovalent small molecules capable of effectively degrading TRK xDFG mutants, providing valuable insights into overcoming TRK xDFG-mediated clinical resistance.

Despite an initial 13 kg weight gain over 9 months, split between fat and lean mass, subsequent fat loss (~3.5 kg) occurred while lean mass was preserved. This case suggests that prolonged, structured exercise is a safe and feasible strategy to attenuate entrectinib-associated metabolic effects and support physical function during targeted therapy in advanced NSCLC.

This includes work that led to the FDA approvals of immune checkpoint inhibitors in multiple rare pediatric tumor types, the NTRK inhibitors larotrectinib, entrectinib, and repotrectinib for children and adults with solid tumors with NTRK fusions, the ALK inhibitor crizotinib in children and adults with ALK-positive inflammatory myofibroblastic tumors, and the radioligand LUATHERA for adolescents and adults with somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors. Despite these advances, the study of rare pediatric cancers faces multiple challenges including a limited number of patients for efficient and well-powered clinical trials and a dearth of financial incentives. Ongoing, coordinated efforts are needed to continue the advancement of novel treatments and improve survival and minimize late effects.

Maximal safe resection followed by chemoradiotherapy with temozolomide remains the standard, with the greatest benefit seen in O6-methylguanine DNA methyltransferase (MGMT) promoter-methylated tumors. Bevacizumab and other targeted modalities offer mainly progression-free, not overall survival, gains. Immune checkpoint inhibitors (e.g., nivolumab) have not improved survival in unselected GBM, while early multi-antigen CAR-T (chimeric antigen receptor T-cell) strategies show preliminary bioactivity without established durability...Future priorities include harmonized imaging molecular integration, AI-driven prognostic modeling, novel PET tracers, and strategies to breach or transiently open the blood-brain barrier to enhance drug delivery. Convergence of these domains may convert diagnostic precision into improved patient outcomes.

Recognition of LG-TNBCs is essential to prevent overtreatment and guide personalized patient management. Molecular characterization provides diagnostic confirmation and therapeutic opportunities, particularly for NTRK-fusion-positive tumors treatable with targeted inhibitors, highlighting the importance of precision medicine in rare breast tumors.

P2, N=100, Active, not recruiting, Gustave Roussy, Cancer Campus, Grand Paris | Trial primary completion date: Sep 2025 --> Apr 2028

The patient remains stable with no evidence of local, nodal, or metastatic disease for more than three years following the initial presentation. This report aims to propose the use of larotrectinib as a management option for recurrent NTRK-positive cervical sarcomas.

Our study reveals a novel mechanism by which the NOTCH2-NTRK1 fusion confers resistance to osimertinib through its interaction with EGFR in NSCLC.