Comparison of clinical efficacy between simultaneous integrated boost intensity-modulated radiotherapy and whole-breast intensity-modulated radiotherapy with sequential electronic boost radiotherapy for early breast cancer after breast-conserving surgery / 肿瘤研究与临床

ABSTRACT

Objective:To compare the efficacy, adverse reactions and skin cosmetic effects between simultaneous integrated boost intensity-modulated radiotherapy and whole-breast intensity-modulated radiotherapy with sequential electronic boost radiotherapy for early breast cancer after breast-conserving surgery.Methods:The clinical data of 96 early breast cancer patients who underwent breast-conserving surgery in Shanxi Province Cancer Hospital from December 2015 to December 2017 were retrospectively analyzed, and the patients were divided into simultaneous integrated boost intensity-modulated radiotherapy group (observation group, 52 cases) and whole-breast intensity-modulated radiotherapy with sequential electronic boost radiotherapy group (control group, 44 cases) according to the postoperative radiotherapy method. In the observation group, the dose division scheme was 50 Gy/25 fractions (2 Gy/fraction) for the whole breast, while 60 Gy/25 fractions (2.4 Gy/fraction) was used in the tumor bed concomitantly, with a total treatment course of 33-35 d. In the control group, the dose division scheme was 50 Gy/25 fractions (2 Gy/ fraction) for the whole breast followed by tumor bed boost of 10 Gy/5 fractions (2 Gy/fraction), with a total treatment course of 40-42 d.Results:Median follow-up time of all patients was 70 months, the 5-year overall survival rates of the observation and control groups were 100.0% and 97.7%, the 5-year local recurrence-free survival rates were 98.1% and 95.5%, the 5-year disease-free survival rates were 98.1% and 93.2%, and the differences between the two groups in terms of overall survival, recurrence-free survival and disease-free survival were not statistically significant ( χ2 = 1.18, P = 0.277; χ2 = 0.44, P = 0.509; χ2 = 1.24, P = 0.265). The incidence of grade 1 and 2 acute radiation dermatitis was 63.5% (33/52) and 19.2% (10/52) in the observation group, and 50.0% (22/44) and 38.6% (17/44) in the control group, there was 1 case (2.3%) of grade 3 acute radiation dermatitis, and the difference between the two groups was statistically significant ( Z = -2.15, P = 0.032). The differences in the incidence of acute and late radiation lung injury between the two groups were not statistically significant (both P > 0.05). Except for 1 patient (2.3%) in the control group with poor cosmetic results, the rest of the patients in both groups achieved average or excellent cosmetic results ( P > 0.05). The radiotherapy time of the observation group was shorter than that of the control group, and the difference was statistically significant ( P = 0.001). Conclusions:Early breast cancer patients who received simultaneous integrated boost intensity-modulated radiotherapy or whole-breast intensity-modulated radiotherapy with sequential electronic boost radiotherapy after breast-conserving surgery could obtain good survival benefit, and the cosmetic results are all good without serious adverse effects. The treatment time of simultaneous integrated boost intensity-modulated radiotherapy is shorter and patient compliance is better.