{
  "abstract": "Background: Adenocarcinoma with high-grade fetal morphology can create diagnostic uncertainty when it presents intracranially without an identifiable systemic primary.\n\nCase presentation: A 61-year-old man presented with gait instability for more than 1 month, dizziness, and left-sided hearing loss. CT and MRI showed a left cerebellopontine angle (CPA)-region mass with heterogeneous avid enhancement, fourth-ventricle compression, and suspected brainstem invasion, without internal auditory canal enlargement. On contrast-enhanced T1-weighted MRI, the lesion measured 37.6 × 24.7 × 35.9 mm (left-to-right [transverse] × anteroposterior × craniocaudal). Initial thoracic CT identified no pulmonary lesion. Subtotal resection was performed because of dense adherence to cranial nerves and the brainstem. Histology showed complex fetal-type glandular and papillary architecture, supranuclear and subnuclear vacuoles, high-grade atypia, and necrosis. The integrated diagnosis was metastatic adenocarcinoma with high-grade fetal morphology, favoring pulmonary origin; however, no pulmonary primary was identifiable on initial thoracic CT or confirmed pathologically. The diagnosis of pulmonary high-grade fetal adenocarcinoma (HG-FLAC) was therefore not established. Postoperative dysphagia and facial nerve dysfunction developed. Systemic staging remained incomplete; molecular testing and PD-L1 assessment were not performed. Remaining paraffin-embedded tissue was insufficient for additional immunohistochemical studies. No systemic anticancer therapy or radiotherapy was initiated after tertiary-center consultation, and detailed treatment-decision records were unavailable. The patient died 3 months after surgery; the immediate cause was undocumented.\n\nConclusion: This case illustrates an atypical CPA presentation of adenocarcinoma with high-grade fetal morphology. Pulmonary origin was favored but unconfirmed. Diagnostic terminology must reflect this uncertainty, and the short survival cannot establish HG-FLAC-specific prognosis.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Medical Imaging, The Second Affiliated Hospital of Shandong First Medical University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Xiaowen Liu"
    },
    {
      "affs": [
        0
      ],
      "name": "Chengxin Yan"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fwrt6cf1qezkq.bib",
  "cited_by": 0,
  "doi": "10.3389/fonc.2026.1942218",
  "fulltext_url": null,
  "id": "fwrt6cf1qezkq",
  "issns": [
    "2234-943X"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fonc.2026.1942218/full",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2730|Cancer Diagnosis and Treatment"
    ]
  ],
  "openalex": "W7223903559",
  "pdf_url": "https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2026.1942218/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-27",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/fwrt6cf1qezkq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:14Z",
      "native_id": "10.3389/fonc.2026.1942218",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fonc.2026.1942218/full"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2730|Cancer Diagnosis and Treatment",
      "subfield": "oncology"
    }
  ],
  "title": "Case Report: Cerebellopontine angle metastatic adenocarcinoma with high-grade fetal morphology and no identifiable pulmonary primary on initial CT",
  "title_text": "Case Report: Cerebellopontine angle metastatic adenocarcinoma with high-grade fetal morphology and no identifiable pulmonary primary on initial CT",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:14Z",
  "url": "https://research.draconitic.com/paper/fwrt6cf1qezkq",
  "venue": "Frontiers in Oncology",
  "versions": []
}