{
  "abstract": "Background/Aim: The 21-gene recurrence score (RS) assay guides adjuvant chemotherapy decisions in hormone receptor-positive/human epidermal growth factor receptor 2-negative early breast cancer. We evaluated how RS results altered treatment recommendations and were integrated with clinicopathological factors in routine practice.\n\nPatients and Methods: We retrospectively analyzed 41 consecutive patients who underwent RS testing for postoperative treatment planning at a single institution. Pre-test and post-test treatment recommendations were compared. Exploratory analyses examined patients with RS ≤25 who received chemotherapy and treatment patterns in node-positive disease.\n\nResults: Median age was 58 years; 20 patients (48.8%) had node-positive disease. RS was 0-10 in nine patients (22.0%), 11-25 in 25 (61.0%), and ≥26 in 7 (17.1%). Treatment recommendations changed in 16 patients (39.0%): chemotherapy was omitted in 13 (31.7%) and added in 3 (7.3%). Among 34 patients with RS ≤25, 29 (85.3%) received endocrine therapy alone and 5 (14.7%) received chemo-endocrine therapy. Patients receiving chemotherapy were younger (median 48 vs. 59 years, p=0.049) and had higher RS values (median 17 vs. 13, p=0.007). Among 20 node-positive patients, 15 (75.0%) received endocrine therapy alone.\n\nConclusion: RS testing altered adjuvant treatment recommendations in 39.0% of patients, predominantly through chemotherapy omission. In patients with RS ≤25, younger age and higher RS were associated with chemotherapy use, suggesting that genomic and clinicopathological information were integrated in routine decision-making.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Breast Surgery, Osaka Rosai Hospital, Osaka, Japan"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "NOBUYOSHI KITTAKA"
    },
    {
      "affs": [
        0
      ],
      "name": "NAMIKO TANAKA"
    },
    {
      "affs": [
        0
      ],
      "name": "CHISATO TAKEUCHI"
    },
    {
      "affs": [
        0
      ],
      "name": "KANA ANNO"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/cg8kw39nyex1b.bib",
  "cited_by": 0,
  "doi": "10.21873/invivo.14506",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13723983/",
  "id": "cg8kw39nyex1b",
  "issns": [
    "0258-851X",
    "1791-7549"
  ],
  "landing_url": "https://doi.org/10.21873/invivo.14506",
  "language": "en",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Research Article"
    ],
    [
      "openalex",
      "1306|Breast Cancer Treatment Studies"
    ]
  ],
  "openalex": "W7224245982",
  "pdf_url": "https://iv.iiarjournals.org/content/invivo/40/6/3678.full.pdf",
  "pmcid": "PMC13723983",
  "pmid": "42957246",
  "published": "2026-10-29",
  "publisher": "International Institute of Anticancer Research",
  "ris": "https://research.draconitic.com/paper/cg8kw39nyex1b.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T12:22:31Z",
      "native_id": "PMC13723983",
      "source": "pmc",
      "url": "https://doi.org/10.21873/invivo.14506"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:1306|Breast Cancer Treatment Studies",
      "subfield": "oncology"
    }
  ],
  "title": "Real-world Impact of the 21-Gene Recurrence Score on Adjuvant Treatment Decisions in Early Breast Cancer",
  "title_text": "Real-world Impact of the 21-Gene Recurrence Score on Adjuvant Treatment Decisions in Early Breast Cancer",
  "type": "peer-reviewed",
  "updated_at": "2026-11-05T12:20:42Z",
  "url": "https://research.draconitic.com/paper/cg8kw39nyex1b",
  "venue": "In Vivo",
  "versions": []
}