NTRK2 fusion

Genomic profiling yields clinically actionable information for approved therapies and evidence of resistance, and it may uncover rational therapeutic opportunities regardless of tumor type.

Our standard operating procedure (SOP) was updated to perform orthogonal confirmation testing for stand-alone equivocal NTRK1/2 and equivocal NTRK3 (5' failure), but to ignore equivocal NTRK3 (5' intact) and report as NTRK2/3 indeterminate. Re-verification showed no change to ALK, ROS1, RET, MET ex14, and NTRK1 results. Sensitivity of NTRK2 detection was significantly increased (80% after orthogonal testing).

The routine use of RNA-based CGP analysis allows for the comprehensive detection of oncogenic fusions in patients with cancer. The diversity of tumor types in which actionable fusions were detected supports the broader utilization of CGP to potentially increase targeted therapy usage and improve outcomes across cancer subtypes.

Emerging structural variants (eSVs) were found to have a combined prevalence to be 0.7%, with only 47.5% of eSVs detected by DNA-NGS. In this cohort study, the detection of structural variants via concurrent RNA-NGS and DNA-NGS was higher across multiple NCCN-guideline recommended biomarkers compared with DNA-NGS alone, suggesting that RNA-NGS should be routinely implemented in the care of patients with advanced NSCLC.

P2, N=70, Active, not recruiting, Children's Oncology Group | Trial completion date: Sep 2024 --> Sep 2025

P=N/A, N=150, Recruiting, Bayer | N=300 --> 150

P2, N=13, Recruiting, Children's Hospital of Philadelphia | Trial primary completion date: Oct 2024 --> Oct 2026

Clinical, histopathological, immunohistochemical, and molecular analyses were performed to diagnose these patients. This report adds to the growing body of knowledge on NTRK-rearranged Spitz lesions and underscores the importance of integrating molecular findings with morphological and immunohistochemical data for the accurate classification and understanding of these neoplasms.

Actionable gene fusions are more prevalent in MSI-H, RAS/BRAF wildtype, or RNF43-mutated CRC, as well as in colon cancer. Mapping of these molecular markers can markedly increase the fusion detection rate, which can help clinicians select candidates for fusion testing and targeted therapy.

The patient in case 2 had no other known tumors at the time of diagnosis, but no follow-up is available. We believe the reported cases represent a hitherto unrecognized variant of "NTRK-rearranged spindle cell neoplasms" of the uterine cervix with novel EGFR mutations.

Finally, we show that ERK activation promotes resistance to TRK kinase inhibition and identify MEK inhibition as a potential combination therapy. These models will be invaluable tools to study therapy resistance of NTRK fusion tumors.

Overall, our results suggest that the all-in-one bimodal DNA/RNA panel is reliable for detecting diagnostic gene alterations in accordance with the latest WHO classification. The integrative pathological and molecular strategy could be valuable in confirmation of diagnosis and selection of treatment options for brain tumors.

Presently, after 22 months of treatment, the patient's complete remission is sustained. Our findings highlight the importance of screening for other oncogenic drivers in BRAF-negative LGGs since rare fusion genes may serve as targets for precision oncology therapy.

This inaugural multicenter study introduces a novel algorithm for detecting and treating sole reciprocal fusions in advanced cancers, expanding the patient population potentially amenable to KIs.

Both larotrectinib and entrectinib are tropomyosin receptor kinase inhibitors with tissue-agnostic approvals for the treatment of patients with solid tumors harboring an NTRK fusion. To our knowledge, this is the first report of a patient with an infantile HGG receiving targeted therapy as first-line treatment with prolonged stable disease. A prospective study of larotrectinib in patients with newly diagnosed infant HGG is ongoing, and will hopefully help answer questions about durability of response, the need for additional therapies, and long-term toxicities seen with TRK inhibitors.

Importantly, co-occurrence of rare fusions and EGFR classical activating mutations in patients pre-treated with anti-EGFR therapy suggests a potential resistance mechanism and consideration of upfront, dual mutation, targeted treatment to improve outcomes. Further clinical studies are needed to validate the best treatment options for these patients with rare fusions.

In a real-world, retrospective analysis of a cohort of advanced NSCLC patients, most oncologists utilized CGP to identify and treat patients with guideline-recommended variant matched targeted therapy, with adherence rates varying by variant. Importantly, even patients that received CGP results prior to FDA approval of novel therapies, received matched therapy once they were included in guidelines.

Tyrosine kinase inhibitors i.e, sorafenib and lenvatinib, have been used in cases of progressive, recurrent, or metastatic disease not responsive to 131I therapy. PDTC accounts for 3–5% of all thyroid carcinomas. The 5, 10-, and 15-year survival rates of patients are 50–85%, 34–50%, and 0%, respectively. RAS gene alterations are found in 25–35%, BRAF mutation in 15–27%, TERT promoter mutation in 40% and mutant TP53 in 16–28% of PDTCs.

Results The 64 patients with colorectal cancer were at a male-to-female ratio of 1.21∶1,with the mean age of (56.59±13.27) years.The tumors were located in the colon in 46(71.88%) patients and in the rectum in 18(28.12%) patients.Sixty(93.75%) patients presented adenocarcinoma,and 4(6.25%) patients presented other types of tumors.The patients in T1/T2 and T3/T4 phases accounted for 17.19%(n=11) and 82.81%(n=53),respectively.Lymph node metastasis occurred in 24(37.50%) patients.The immunohistochemical staining results showed partially down-regulated or absent expression of SMARCA4 in 1(1.56%) patient,positive BRAF expression in 4(6.25%) patients,and mutant expression of P53 in 35(54.69%) patients.The PD-1-expressing tumor associated immune cell was proportion score<10% in 45(70.31%) patients and≥10% in 19(29.69%) patients.The PD-L1 combined positive score was<10 in 52(81.25%) patients and≥10 in 12(18.75%) patients.The gene fusion of NTRK1,NTRK2,and NTRK3 was negative in all the patients,and BRAF V600E gene mutation was positive in 4(6.25%) patients.The SMARCA4 gene alteration was not detected in the patient with partial expression missing of SMARCA4.The PD-L1 combine positive score was correlated with the deficient mismatch repair(dMMR)/microsatellite instability-high (MSI-H) and the PD-1 expression (χ2=10.223,P=0.001;χ2=11.979,P=0.001). Conclusions The down-regulated or absent SMARCA4 expression and NTRK gene fusion are rare in the patients with colorectal cancer in Tibet.A few patients present BRAF V600E gene mutations,and Pan-TRK and BRAF expression can be used for the primary screening of NTRK gene fusion and BRAF gene mutation.The patients with dMMR/MSI-H are prone to high expression of PD-L1 and expected to benefit from immunotherapy.No significant correlation exists between P53 mutation and PD-L1 expression.The high expression of PD-1 is positively correlated with the high expression of PD-L1.

Real-world datasets from clinical panel testing revealed the genomic landscape in gastric cancer by subgroup. These findings provide insights for the current therapeutic strategies and future development of treatments in gastric cancer.

P2, N=60, Not yet recruiting, Teligene US | Initiation date: Jan 2024 --> May 2024

After pursuing other alternative treatments, including chemotherapy (ie, carboplatin, etoposide, capecitabine, temozolomide, and paclitaxel), everolimus, and atezolizumab, she returned with significant progression, including innumerable subcutaneous nodules, left pleura metastasis, multiple bone metastases, and brain metastases. To date, she has maintained sustained benefit for at least 1 year from initiation of entrectinib. Here, we present the first case of a female patient with metastatic AC harboring the ETV6-NTRK2 fusion, and successfully treated with entrectinib, providing evidence for the application of entrectinib in patients with NTRK-positive AC, and underscoring the critical role of molecular profiling for such cases.

Recent approval of the TRK inhibitor larotrectinib by the Food and Drug Administration (FDA) has brought interest in the study and recognition of NTRK fusions in multiple types of tumors. Trials that assess the response to this drug in cancers carrying NTRK fusions have yielded favorable results. We discuss a rare presentation of an adult-type GBM with epithelioid morphology and a BCR::NTRK2 gene fusion.

One patient was succumbed to the disease at 12 months despite adjunctive treatment with TRK inhibitor larotrectinib after surgery...The final diagnosis relies on molecular assays. Patients with advanced disease may benefit from TRK inhibitor treatment.

P2, N=70, Active, not recruiting, Children's Oncology Group | Trial completion date: Mar 2024 --> Sep 2024 | Trial primary completion date: Mar 2024 --> Sep 2024

P2, N=146, Recruiting, Genentech, Inc. | N=85 --> 146

P2, N=85, Recruiting, Genentech, Inc. | Trial primary completion date: Mar 2024 --> Dec 2025

A well-designed DNA CGP assay is capable of robust fusion detection and these fusion calls are reliable for informing clinical decision-making. While DNA CGP detects most driver fusions, the clinical impact of fusion detection is substantial for individual patients and exhaustive efforts, inclusive of additional RNA-based testing, should be considered when an oncogenic driver is not clearly identified.

P1/2, N=69, Active, not recruiting, Hoffmann-La Roche | Trial primary completion date: Mar 2023 --> Jun 2025

P2, N=13, Recruiting, Children's Hospital of Philadelphia | Not yet recruiting --> Recruiting

Touch imprint slides provide a reliable alternative, especially when neoplastic cells are scarce in permanent biopsies or decalcification deters nucleic acid quality. Based on our experience, we suggest making touch imprints on a routine basis, especially for every bone biopsy. Once digitally scanned duplicates are made, original slides can be safely used for DNA-/RNA-based molecular studies.

P2, N=215, Active, not recruiting, Bayer | Recruiting --> Active, not recruiting

However, there was not clear difference in clinical outcomes according to the trkB expression status in small intestinal GISTs. These findings may provide a possible hypothesis for trkB overexpression contributing to the tumorigenesis and aggressive clinical outcome in GISTs of duodenal origin.

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.

To the best of our knowledge, we reported the first case demonstrating anti-tumor activity of repotrectinib in a patient with AC carring an ETV6-NTRK3 gene fusion, indicating that repotrectinib may be an efficient therapeutic option for tumors with NTRK gene rearrangements.

P1/2, N=50, Recruiting, Memorial Sloan Kettering Cancer Center

A ROS1-rearranged NSCLC with CNS metastases responded to sequential tyrosine kinase inhibitors treatment of crizotinb followed by entrectinib. This report has potential implications in guiding decisions for the treatment after crizotinib resistance.

A ternary classification Spitz nevus-Spitz melanocytoma-Spitz melanoma is more adherent to the real neoplastic pathway, but some cases with intermediate ambiguous features remain difficult to diagnose. A prognostic stratification of Spitz tumors, based on the morphologic and genomic characteristics, as a complement to the diagnosis, may contribute to better treatment plans for patients.

P2, N=13, Not yet recruiting, Children's Hospital of Philadelphia | Initiation date: Nov 2023 --> Feb 2024

Two cases were classified as Spitz nevus, while the remaining neoplasm was classified as Spitz melanoma at the time of the diagnosis, given 9p21 homozygous deletion and positive sentinel lymph node biopsy. We suggest that RAF1 fused melanocytic neoplasms can represent a novel subgroup of Spitz tumors, with a RAF1 fusion representing an oncogenic driver.

We present the second detailed case of an intraventricular presentation in the MC EVN. Our findings broaden the spectrum of MC EVN and have implications in terms of diagnosis, therapy and terminology.

These modifications altered the response to TKI treatment both in vitro and in vivo. Overall, these models serve as valuable tools for studying the biology of NTRK fusion tumors, their treatment response in a treatment-naïve or -experienced state, and the mechanisms underlying treatment resistance.