Metastatic pulmonary ETV6::NTRK3 mucinous adenocarcinoma originating from an intraductal papillary mucinous neoplasm case report
Year: 2026
Type: article
Abstract: Background: Mucinous neoplasms of the lung are difficult to differentiate from upper gastrointestinal neoplasms based on pathologic appearance and immunohistochemistry (IHC) alone. Both variably express cytokeratin 7 (CK7), cytokeratin 20 (CK20), and caudal type homeobox 2 (CDX2), while often lacking thyroid transcription factor 1 (TTF-1) and Napsin-A. Case Description: fusion. The patient started systemic therapy with larotrectinib, which led to clinical improvement and resolution of all lung lesions with response ongoing at the time of publication. Conclusions: fusions, while rare, occur across the spectrum of epithelial neoplasms, including IPMNs. In this case thorough molecular testing of both the active pulmonary malignancy and the antecedent pancreatic premalignancy identified the likely etiology of the mucinous adenocarcinoma and allowed for treatment with effective oral therapy.
Institutions: University of Washington, Fred Hutch Cancer Center
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7223907798