{
  "abstract": "Early-onset bilateral and multifocal clear cell renal cell carcinoma (ccRCC) is rare and suggests hereditary predisposition. We report a 36-year-old Polish male who presented with hematuria and flank pain. Imaging revealed a right renal mass; nephron-sparing surgery confirmed low-grade ccRCC (pT1a). One year later, multifocal left-sided ccRCC was diagnosed, requiring radical nephrectomy (pT1b). Germline testing identified a heterozygous likely pathogenic splice-region variant CHEK2 (NM_007194.4:c.846 + 4_846 + 7del). Functional data support aberrant splicing and reduced kinase activity. During 11 years of follow-up, the patient remained recurrence-free, with a stable Bosniak IIF lesion in the remaining kidney. This case documents the co-occurrence of early-onset bilateral and multifocal ccRCC with a germline likely pathogenic CHEK2 variant but does not establish a causal relationship. It underscores the value of comprehensive germline testing in atypical RCC and highlights the need for integrated germline-somatic studies to clarify whether CHEK2 variants are associated with renal cancer susceptibility.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Case Report",
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "name": "Ewa Czukiewska"
    },
    {
      "name": "Jacek Kiś"
    },
    {
      "name": "Dominika Szczęśniak"
    },
    {
      "name": "Natalija Sawczuk-Napora"
    },
    {
      "name": "Magdalena Mroczek"
    },
    {
      "name": "Tymoteusz Czukiewski"
    },
    {
      "name": "Kinga Kuranty"
    },
    {
      "name": "Joanna Kozak"
    },
    {
      "name": "Małgorzata Nowak-Kępczyk"
    },
    {
      "name": "Agnieszka Kuźniar"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0g74mzy2g5yf1.bib",
  "cited_by": 0,
  "doi": "10.3389/fonc.2026.1969693",
  "fulltext_url": null,
  "id": "0g74mzy2g5yf1",
  "issns": [
    "2234-943X"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fonc.2026.1969693",
  "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": [
    [
      "feed-journal",
      "medicine/oncology"
    ]
  ],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-05",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/0g74mzy2g5yf1.ris",
  "sources": [
    {
      "first_seen": "2026-11-05T06:20:20Z",
      "native_id": "10.3389/fonc.2026.1969693",
      "source": "feed-frontiers",
      "url": "https://www.frontiersin.org/articles/10.3389/fonc.2026.1969693"
    },
    {
      "first_seen": "2026-11-05T12:21:27Z",
      "native_id": "10.3389/fonc.2026.1969693",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fonc.2026.1969693/full"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "feed-journal:medicine/oncology",
      "subfield": "oncology"
    }
  ],
  "title": "Case Report: Early-onset bilateral and multifocal clear cell renal cell carcinoma in a carrier of the germline likely pathogenic CHEK2 splice-region variant NM_007194.4:c.846 + 4_846 + 7del",
  "title_text": "Case Report: Early-onset bilateral and multifocal clear cell renal cell carcinoma in a carrier of the germline likely pathogenic CHEK2 splice-region variant NM_007194.4:c.846 + 4_846 + 7del",
  "type": "peer-reviewed",
  "updated_at": "2026-11-07T00:21:24Z",
  "url": "https://research.draconitic.com/paper/0g74mzy2g5yf1",
  "venue": "Frontiers in Oncology",
  "versions": []
}