{
  "abstract": "Ultrahypofractionated whole-breast radiotherapy reduces treatment burden but increases the importance of accurate dose delivery at each fraction. This retrospective single-center study evaluated cone-beam computed tomography-guided online adaptive radiotherapy in 55 patients with early-stage breast cancer treated with 26 or 27 Gy in five fractions. Dosimetric analysis was available for 52 patients and 259 paired scheduled and adapted fractions. Linear mixed-effects models with a patient-specific random intercept were used to account for repeated fractions within individual patients. The adapted plan was selected for 242 out of 260 delivered fractions (93.1%). Mean planning target volume V95% increased from 93.52 ± 2.94% with the scheduled plan to 98.13 ± 1.04% with adaptation (p < 0.001), with reduced interfraction variability. Ipsilateral lung V30% increased modestly from 13.94% to 14.96% (p < 0.001). In left-sided cases, no significant differences were observed for heart V25% (1.400% vs. 1.395%; p = 0.3825) or left anterior descending coronary artery D0.03 cm³ (1.771 vs. 1.873 Gy; p = 0.1390). Acute grade 1 toxicity occurred in five patients (9.1%), with no grade ≥ 2 events. Mean treatment-session duration was 28 min. Online adaptation significantly improved daily target coverage and was technically feasible within a five-fraction whole-breast workflow. Acute toxicity was limited in this cohort, while longer follow-up and cumulative dose analyses are needed to further define its impact on organ-at-risk exposure and clinical outcomes.",
  "abstract_shown": true,
  "affiliations": [
    "Specialty Hospital Radiochirurgia Zagreb, 10431 Sveta Nedelja, Croatia.",
    "Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia.",
    "Medical Faculty Osijek, University Josip Juraj Strossmayer in Osijek, 31000 Osijek, Croatia.",
    "Medical Faculty, Juraj Dobrila University of Pula, 52100 Pula, Croatia."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Giovanni Ursi"
    },
    {
      "affs": [
        0
      ],
      "name": "Matea Lekić",
      "orcid": "0000-0001-7282-1869"
    },
    {
      "affs": [
        0
      ],
      "name": "Hrvoje Kaučić",
      "orcid": "0000-0002-9451-1762"
    },
    {
      "affs": [
        0
      ],
      "name": "Aleksandar Kovačević"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Domagoj Kosmina",
      "orcid": "0000-0002-4099-9002"
    },
    {
      "affs": [
        0
      ],
      "name": "Karla Schwarz"
    },
    {
      "affs": [
        0,
        2,
        3
      ],
      "name": "Dragan Schwarz"
    },
    {
      "affs": [
        0
      ],
      "name": "Damir Vučinić",
      "orcid": "0000-0002-5804-0799"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5r56ed599gv9x.bib",
  "cited_by": 0,
  "doi": "10.3390/curroncol33100634",
  "fulltext_url": "https://europepmc.org/articles/PMC13703279",
  "id": "5r56ed599gv9x",
  "issns": [
    "1198-0052",
    "1718-7729"
  ],
  "landing_url": "https://europepmc.org/article/MED/42930201",
  "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",
      "3108|Advanced Radiotherapy Techniques"
    ]
  ],
  "openalex": "W7223045215",
  "pdf_url": "https://europepmc.org/articles/PMC13703279?pdf=render",
  "pmcid": "PMC13703279",
  "pmid": "42930201",
  "published": "2026-10-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5r56ed599gv9x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:01Z",
      "native_id": "MED:42930201",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42930201"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3108|Advanced Radiotherapy Techniques",
      "subfield": "applied-instrumentation"
    }
  ],
  "title": "CBCT-Guided Online Adaptive Ultrahypofractionated Whole-Breast Radiotherapy for Early-Stage Breast Cancer: Dosimetric Outcomes and Acute Toxicity.",
  "title_text": "CBCT-Guided Online Adaptive Ultrahypofractionated Whole-Breast Radiotherapy for Early-Stage Breast Cancer: Dosimetric Outcomes and Acute Toxicity.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:22:01Z",
  "url": "https://research.draconitic.com/paper/5r56ed599gv9x",
  "venue": "Current oncology (Toronto, Ont.)",
  "versions": []
}