Long‐term outcomes of patients with conserved breast cancer treated with adjuvant hypofractionated prone breast intensity‐modulated radiation therapy. Issue 6 (16th June 2020)

• Record Type: Journal Article
• Authors: Gortman, Aron M; Aherne, Noel J; Amalaseelan, Julan; Last, Andrew; Westhuyzen, Justin; Chamberlain, Lauren; Shakespeare, Thomas P
• Is Part Of: Journal of medical imaging and radiation oncology. Volume 64:Issue 6(2020:Dec.)
• Page Start: 845
• Page End: 851
• Publication Date: 2020-06-16
• Subjects: breast cancer -- hypofractionation -- intensity‐modulated radiotherapy -- prone positioning -- radiation therapy; Radiology, Medical -- Periodicals; Radiology, Medical -- Australasia -- Periodicals; 616.0757
• DOI: 10.1111/1754-9485.13072
• Languages: English
• ISSNs: 1754-9477

Abstract

Abstract: Introduction: New techniques for adjuvant radiation therapy after breast conservation include prone positioning, hypofractionation and intensity‐modulated radiation therapy (IMRT). Long‐term evaluations of this combination are lacking, and we report our own experience. Methods: Patients with invasive breast cancer followed for a minimum 36 months post‐IMRT were eligible. Dose used was 40 Gray in 15 fractions over 3 weeks to the whole breast via forward‐planned prone, whole breast IMRT. A 10 Gy in 5 fraction supine boost was offered. Results: Between January 2012 and January 2020, 2199 patients had breast conservation and adjuvant radiation: 489 received hypofractionated prone breast IMRT, with 155 eligible for our evaluation. Median follow‐up was 52 months. Median age was 62 (range 36–80), 78.7% were T1, 20.6% were T2, and 12.3% were node‐positive. Grade was 1 in 26.5%, 2 in 43.9% and 3 in 29.7%; 87.1% were oestrogen receptor positive, 3.2% were HER2 positive, and 11.0% were triple negative. 58.6% received a boost, 74.8% endocrine therapy and 32.3% chemotherapy. No patient developed local recurrence. One regional recurrence was successfully salvaged. Six patients (3.9%) developed metastases, and 1.9% died. Five‐year actuarial local recurrence‐free, regional recurrence‐free and breast cancer‐specific survival rates were 100.0%, 98.2% and 94.8%. Late grade 1 and 2 breast pain occurred in 20.0% and 1.3% of patients. Only 11.0% had new pain compared to pre‐radiation. No patient developed radiation‐induced pneumonitis, pulmonary fibrosis, rib fracture or cardiac toxicity. All patients scored cosmesis as 'good' or better. Conclusion: Adjuvant hypofractionated prone breast IMRT has excellent locoregional control and minimal toxicity.