TY - JOUR
T1 - Proton Accelerated Partial Breast Irradiation
T2 - Clinical Outcomes at a Planned Interim Analysis of a Prospective Phase 2 Trial
AU - Pasalic, Dario
AU - Strom, Eric A.
AU - Allen, Pamela K.
AU - Williamson, Tyler D.
AU - Poenisch, Falk
AU - Amos, Richard A.
AU - Woodward, Wendy A.
AU - Stauder, Michael C.
AU - Shaitelman, Simona F.
AU - Smith, Benjamin D.
AU - Perkins, George H.
AU - Tereffe, Welela
AU - Hoffman, Karen E.
N1 - Publisher Copyright:
© 2020 Elsevier Inc.
PY - 2021/2/1
Y1 - 2021/2/1
N2 - Purpose: To perform a planned interim analysis of acute (within 12 months) and late (after 12 months) toxicities and cosmetic outcomes after proton accelerated partial breast irradiation (APBI). Methods and Materials: A total of 100 patients with pTis or pT1-2 N0 (≤3cm) breast cancer status after segmental mastectomy were enrolled in a single-arm phase 2 study from 2010 to 2019. The clinically determined postlumpectomy target volume, including tumor bed surgical clips and operative-cavity soft-tissue changes seen on imaging plus a radial clinical expansion, was irradiated with passively scattered proton APBI (34 Gy in 10 fractions delivered twice daily with a minimum 6-hour interfraction interval). Patients were evaluated at protocol-specific time intervals for recurrence, physician reports of cosmetic outcomes and toxicities, and patient reports of cosmetic outcomes and satisfaction with the treatment or experience. Results: Median follow-up was 24 months (interquartile range [IQR], 12-43 months). Local control and overall survival were 100% at 12 and 24 months. There were no acute or late toxicities of grade 3 or higher; no patients experienced fat necrosis, fibrosis, infection, or breast shrinkage. Excellent or good cosmesis at 12 months was reported by 91% of patients and 94% of physicians; at the most recent follow-up, these were 94% and 87%, respectively. The most commonly reported late cosmetic effect was telangiectasis (17%). The total patient satisfaction rate for treatment and results at 12 and 24 months was 96% and 100%, respectively. Patients’ mean time away from work was 5 days (IQR, 2-5 days), and the median out-of-pocket cost was $700 (IQR, $100-$1600). The mean left-sided heart dose was 2 cGy (range, 0.2-75 cGy), and the mean ipsilateral lung dose was 19 cGy (range, 0.2-164 cGy). Conclusions: Proton APBI is a maturing treatment option with high local control, favorable intermediate-term cosmesis, high treatment satisfaction, low treatment burden, and exceptional heart and lung sparing.
AB - Purpose: To perform a planned interim analysis of acute (within 12 months) and late (after 12 months) toxicities and cosmetic outcomes after proton accelerated partial breast irradiation (APBI). Methods and Materials: A total of 100 patients with pTis or pT1-2 N0 (≤3cm) breast cancer status after segmental mastectomy were enrolled in a single-arm phase 2 study from 2010 to 2019. The clinically determined postlumpectomy target volume, including tumor bed surgical clips and operative-cavity soft-tissue changes seen on imaging plus a radial clinical expansion, was irradiated with passively scattered proton APBI (34 Gy in 10 fractions delivered twice daily with a minimum 6-hour interfraction interval). Patients were evaluated at protocol-specific time intervals for recurrence, physician reports of cosmetic outcomes and toxicities, and patient reports of cosmetic outcomes and satisfaction with the treatment or experience. Results: Median follow-up was 24 months (interquartile range [IQR], 12-43 months). Local control and overall survival were 100% at 12 and 24 months. There were no acute or late toxicities of grade 3 or higher; no patients experienced fat necrosis, fibrosis, infection, or breast shrinkage. Excellent or good cosmesis at 12 months was reported by 91% of patients and 94% of physicians; at the most recent follow-up, these were 94% and 87%, respectively. The most commonly reported late cosmetic effect was telangiectasis (17%). The total patient satisfaction rate for treatment and results at 12 and 24 months was 96% and 100%, respectively. Patients’ mean time away from work was 5 days (IQR, 2-5 days), and the median out-of-pocket cost was $700 (IQR, $100-$1600). The mean left-sided heart dose was 2 cGy (range, 0.2-75 cGy), and the mean ipsilateral lung dose was 19 cGy (range, 0.2-164 cGy). Conclusions: Proton APBI is a maturing treatment option with high local control, favorable intermediate-term cosmesis, high treatment satisfaction, low treatment burden, and exceptional heart and lung sparing.
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U2 - 10.1016/j.ijrobp.2020.09.009
DO - 10.1016/j.ijrobp.2020.09.009
M3 - Article
C2 - 32946965
AN - SCOPUS:85092768799
SN - 0360-3016
VL - 109
SP - 441
EP - 448
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
IS - 2
ER -