{
  "abstract": "Undifferentiated pleomorphic sarcoma (UPS) is an exceptionally rare mesenchymal neoplasm in the feline oral cavity, presenting significant diagnostic and therapeutic challenges. A 10-year and 10-month-old, castrated male Korean Shorthair cat presented with a progressively enlarging sublingual mass measuring 2.77 cm × 3.02 cm × 1.86 cm. Computed tomography revealed a well-circumscribed, non-osteolytic sublingual mass without detectable mandibular bone erosion or regional lymphadenopathy. Gross complete surgical excision was performed via a transoral approach without mandibulectomy. Histopathological examination revealed a highly pleomorphic, sheet-like proliferation of atypical spindle to epithelioid cells with prominent giant binucleated cells and a low mitotic count (3 per 10 high-power fields). To establish a diagnosis of exclusion, an extensive immunohistochemical (IHC) panel was performed. The neoplastic cells were strongly positive for vimentin and diffusely positive for S100, but immunonegative for pancytokeratin (PanCK), Melan-A, Iba-1, desmin, and α-smooth muscle actin (α-SMA). These exclusionary IHC findings did not support epithelial, histiocytic, or myogenic differentiation, though amelanotic melanoma cannot be completely excluded based on Melan-A negativity alone. Rather than confirming definitive neural differentiation, the diffuse S100 immunoreactivity supported a final diagnosis of an S100-positive UPS. The patient achieved rapid functional recovery, with owner-reported absence of clinical signs of local recurrence over a 90-day follow-up period. This report underscores the necessity of a broad exclusionary IHC panel to accurately diagnose feline oral UPS and highlights surgical resection as a viable local management option.",
  "abstract_shown": true,
  "affiliations": [
    "Gonggam Animal Medical Center, Gwangju 62225, Republic of Korea.",
    "Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea."
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Yoo Suk Kim"
    },
    {
      "affs": [
        1
      ],
      "name": "Hwi-Yool Kim",
      "orcid": "0000-0001-6237-9958"
    },
    {
      "affs": [
        0
      ],
      "name": "Kwangsik Jang",
      "orcid": "0000-0001-9273-7269"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/df6jv4v12sxbg.bib",
  "cited_by": 0,
  "doi": "10.3390/vetsci13101036",
  "fulltext_url": "https://europepmc.org/articles/PMC13709510",
  "id": "df6jv4v12sxbg",
  "issns": [
    "2306-7381"
  ],
  "landing_url": "https://europepmc.org/article/MED/42944132",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2740|Veterinary Oncology Research"
    ]
  ],
  "openalex": "W7214888219",
  "pdf_url": "https://europepmc.org/articles/PMC13709510?pdf=render",
  "pmcid": "PMC13709510",
  "pmid": "42944132",
  "published": "2026-09-30",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/df6jv4v12sxbg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:24Z",
      "native_id": "MED:42944132",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42944132"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2740|Veterinary Oncology Research",
      "subfield": "general"
    }
  ],
  "title": "Primary Sublingual S100-Positive Undifferentiated Pleomorphic Sarcoma in a Cat: A Case Report with Comprehensive Exclusionary Immunohistochemistry.",
  "title_text": "Primary Sublingual S100-Positive Undifferentiated Pleomorphic Sarcoma in a Cat: A Case Report with Comprehensive Exclusionary Immunohistochemistry.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:22:24Z",
  "url": "https://research.draconitic.com/paper/df6jv4v12sxbg",
  "venue": "Veterinary sciences",
  "versions": []
}