Abstract
IMPORTANCE Conventional adjuvant radiotherapy for breast cancer given daily for several weeks is onerous and expensive. Some patients may be obliged to choose a mastectomy instead, and some may forgo radiotherapy altogether. We proposed a clinical trial to test whether radiotherapy could be safely limited to the tumor bed. OBJECTIVE To determine whether delayed second-procedure targeted intraoperative radiotherapy (TARGIT-IORT) is noninferior to whole-breast external beam radiotherapy (EBRT) in terms of local control. DESIGN, SETTING, AND PARTICIPANTS In this prospective, randomized (1:1 ratio) noninferiority trial, 1153 patients aged 45 years or older with invasive ductal breast carcinoma smaller than 3.5 cm treated with breast conservation were enrolled from 28 centers in 9 countries. Data were locked in on July 3, 2019. INTERVENTIONS The TARGIT-A trial was started in March 2000;patients were randomized after needle biopsy to receive TARGIT-IORT immediately after lumpectomy under the same anesthetic vs EBRT and results have been shown to be noninferior. A parallel study, described in this article, was initiated in 2004;patients who had their cancer excised were randomly allocated using separate randomization tables to receive EBRT or delayed TARGIT-IORT given as a second procedure by reopening the lumpectomy wound. MAIN OUTCOMES AND MEASURES A noninferiority margin for local recurrence rate of 2.5% at 5 years, and long-term survival outcomes. RESULTS Overall, 581 women (mean [SD] age, 63 [7] years) were randomized to delayed TARGIT-IORT and 572 patients (mean [SD] age, 63 [8] years) were randomized to EBRT. Sixty patients (5%) had tumors larger than 2 cm, or had positive nodes and only 32 (2.7%) were younger than 50 years. Delayed TARGIT-IORT was not noninferior to EBRT. The local recurrence rates at 5-year complete follow-up were: delayed TARGIT-IORT vs EBRT (23/581 [3.96%] vs 6/572 [1.05%], respectively;difference, 2.91%;upper 90% CI, 4.4%). With long-term follow-up (median [IQR], 9.0 [7.5-10.5] years), there was no statistically significant difference in local recurrence-free survival (HR, 0.75;95% CI, 0.57-1.003;P = .052), mastectomy-free survival (HR, 0.88;95% CI, 0.65-1.18;P = .38), distant disease-free survival (HR, 1.00;95% CI, 0.72-1.39;P = .98), or overall survival (HR, 0.96;95% CI, 0.68-1.35;P = .80). CONCLUSIONS AND RELEVANCE These long-term data show that despite an increase in the number of local recurrences with delayed TARGIT-IORT, there was no statistically significant decrease in mastectomy-free survival, distant disease-free survival, or overall survival.
Dokumententyp: | Zeitschriftenartikel |
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Fakultät: | Medizin |
Themengebiete: | 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit |
ISSN: | 2374-2437 |
Sprache: | Englisch |
Dokumenten ID: | 84842 |
Datum der Veröffentlichung auf Open Access LMU: | 25. Jan. 2022, 09:12 |
Letzte Änderungen: | 25. Jan. 2022, 09:12 |