NTRK3 (Neurotrophic tyrosine kinase, receptor, type 3)

P=N/A, N=40, Enrolling by invitation, Chang Gung Memorial Hospital | Not yet recruiting --> Enrolling by invitation

Two relapsed patients received salvage chemotherapy [vincristine-actinomycin D-cyclophosphamide (VAC) or ifosfamide-carboplatin-etoposide (ICE)], which showed limited efficacy. One relapsed patient with TPM3::NTRK1 received larotrectinib but died two months later; another with EGFR-KDD experienced disease stabilization after afatinib plus programmed cell death protein 1 (PD-1) blockade following progression on entrectinib and anlotinib...While most patients experienced favorable outcomes following surgery, relapsed cases highlight the challenges associated with molecularly atypical disease. These observations are descriptive in nature and underscore the need for larger collaborative studies to better define prognostic factors and optimal management strategies in CMN.

We also extensively review the existing literature and summarize the clinicopathological features, molecular profiles, and treatment implications of this report. Given the availability of effective TRK inhibitors, it is imperative to consider NTRK-rearranged sarcoma in the differential diagnosis of spindle cell sarcomas of the lower genital tract.

Cases of malignant peripheral nerve sheath tumours are, in contrast to desmoplastic melanoma S‑100 protein negative or express this marker only focally, and show a decreased nuclear expression of H3K27. Desmoplastic melanoma shows a focal nuclear expression of p53 in contrast to neurofibroma.

Tumors harboring these fusions respond dramatically to TRK inhibitors (e.g., larotrectinib, entrectinib, and repotrectinib), which selectively target the constitutively active fusion protein. Conclusively, this first report of three novel NTRK2 fusion transcript variants co-occurrence in an MTC patient expands the known spectrum of translocation partners in NTRK2 rearrangements. Prospective validation of their impact on TRK-targeted therapy efficacy and disease prognosis requires long-term follow-up.

OFA balances TAT, QNS, and detection, whereas SO-NGS offers comprehensive detection with longer TAT and higher QNS. An optimized assay combining SGP's speed, OFA's reliability, and SO-NGS's comprehensiveness could improve outcomes.

Of 77 unique panels evaluated, only 5 captured all recommended biomarkers for mNSCLC. Ensuring targeted panels assess all relevant biomarkers is crucial for optimal patient treatment.

After adjuvant chemotherapy, maintenance larotrectinib was initiated based on proven TRK inhibitor efficacy in metastatic NTRK-fusion tumors and emerging evidence for targeted therapy benefit in driver-positive early stage lung adenocarcinoma. Our findings demonstrate the value of molecular pathology in the diagnostic journey of pulmonary malignancies, guiding rare fusion detection and supporting therapeutic decisions based on rare fusions in early stage disease.

NTRK3 gene fusions occur in a subset of plaque-like CD34-positive dermal fibromas, providing additional molecular insight into this rare superficial spindle cell lesion. Together with emerging literature, these findings support a role for recurrent kinase gene rearrangements in a subset of CD34-positive plaque-like superficial spindle cell tumours, while underscoring the continued importance of clinicopathologic correlation in defining this evolving spectrum.

Inhibitors such as larotrectinib, entrectinib and repotrectinib are used when cancer cells harbor NTRK1, NTRK2 or NTRK3 fusion...Short courses of prednisone for the former and dexamethasone for the latter were initiated after failure of standard analgesia... For patients experiencing TRK inhibitor withdrawal pain, especially when tapering down the inhibitor is not an available strategy, a short course of corticosteroids can provide lasting relief. These cases emphasize the importance of better understanding the mechanism underlying the relationship between NRTK, NGF and nociception.

NCI-MATCH subprotocol Z1E demonstrates that larotrectinib offers clinically significant benefit with marked ORR across NTRK fusion-positive tumors with no clinically significant toxicities. These findings support the rationale for the US Food and Drug Administration's tissue-agnostic approval of larotrectinib for NTRK fusion-positive tumors. Our findings demonstrate the necessity of including NTRK1, NTRK2, and NTRK3 within comprehensive molecular assays of cancer to navigate patients to an easily administered and highly effective therapy.

P1/2, N=28, Recruiting, Bicycletx Limited