Rachelle P Mendoza, Emily Symes, Peng Wang, Cole Miller, Stephanie C Thompson, Tatjana Antic, Anna Biernacka
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引用次数: 0
Abstract
Background: Spindle cell carcinoid tumor (SCCT) is a rare variant of lung carcinoid tumor consisting predominantly or exclusively of spindle cells. To the authors' knowledge, this is the first study to date investigating the molecular characteristics of SCCTs.
Methods: Eighty-five carcinoid tumors initially diagnosed by fine-needle aspiration over a period of 10 years were reviewed. The final diagnostic classification was based on resection specimens. Six SCCTs were identified and characterized based on cytomorphology, and immunohistochemical and molecular features.
Results: Most patients with SCCT were Caucasian (100.0%), women (83.3%), asymptomatic (66.7%), and nonsmokers (83.3%). The median age at diagnosis was 78.0 years (range, 58.2-80.3 years). A higher proportion of patients who had SCCT were diagnosed with distant metastasis. The smears were cellular and demonstrated clean backgrounds without necrosis or mitotic activity. SCCTs comprised of bipolar-to-elongated cells with finely granular chromatin, inconspicuous nucleoli, scant cytoplasm, and minimal atypia or pleomorphism. The tumor cells sometimes appeared boomerang-shaped and might mimic granulomas or blood vessels. SCCTs showed strong expression for pan-cytokeratin, synaptophysin, chromogranin, and CD56, with weak TTF-1 and a very low Ki-67 proliferation index. All SCCTs had low tumor mutational burden and were microsatellite-stable. One case showed multiple whole-gene losses in chromosome 11, whereas another harbored duplication in ARID1A. Two cases demonstrated gains in chromosomes 17, one of which also showed gains in chromosome 18. None had a single nucleotide mutation.
Conclusions: SCCT is a rare subset of lung carcinoid tumors. These tumors harbor unique cytologic, prognostic, and molecular features that may have significant diagnostic and clinical implications.
期刊介绍:
Cancer Cytopathology provides a unique forum for interaction and dissemination of original research and educational information relevant to the practice of cytopathology and its related oncologic disciplines. The journal strives to have a positive effect on cancer prevention, early detection, diagnosis, and cure by the publication of high-quality content. The mission of Cancer Cytopathology is to present and inform readers of new applications, technological advances, cutting-edge research, novel applications of molecular techniques, and relevant review articles related to cytopathology.