RESUMEN
Objective:To investigate the effect of hybrid intensity modulated radiotherapy (Hy-IMRT) on immune function in patients with locally advanced breast cancer surgery and the treatment efficacy.Methods:A total of 94 patients with locally advanced breast cancer who underwent modified radical mastectomy for breast cancer and required postoperative radiotherapy in Changzhou Cancer Hospital in Jiangsu Province from January 2015 to January 2017 were selected. The patients were divided into Hy-IMRT group (observation group, 47 cases) and three-dimensional conformal radiotherapy (3DCRT) group (control group, 47 cases) according to the random number table method. The dose and related radiophysical parameters of the respective target areas of the two groups, adverse reactions during and after radiotherapy, cytokines and T lymphocyte subsets before and after radiotherapy, 3-year local recurrence rate, distant metastasis rate and mortality were observed and compared between the two groups.Results:The dose obtained by 95% (D 95%) [(4 945.6±36.1) Gy vs. (4 754.0±35.6) Gy] and target area conformity (CI) of the target volume (0.7±0.1 vs. 0.5±0.1) in the observation group were greater than those in the control group, and the differences were statistically significant (both P<0.05); the target volume of 110% of the prescription dose (V 110%) [(1.6±0.5) cm 3 vs. (8.4±1.2) cm 3], the target volume of more than 105% of the prescription dose (V 105%) [(19.3±3.5) cm 3 vs. (26.6±5.6) cm 3] and the heterogeneity index (HI) (1.1±0.1 vs. 1.3±0.1) in the observation group were all smaller than those of the control group, and the differences were statistically significant (all P < 0.05). The incidence of acute skin adverse reactions [53.2% (25/47) vs. 74.5% (35/47)] and the incidence of bone marrow suppression [40.4% (19/47) vs. 70.2% (33/47)] in the observation group were lower than those in the control group, and the differences were statistically significant (both P < 0.05). There were no significant differences in levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), CD4 +, CD8 +, and CD4 +/CD8 + between the two groups before radiotherapy (all P > 0.05). At the end of radiotherapy, the levels of IL-6, TNF-α and CD8 + were higher in both groups than before radiotherapy (all P < 0.05), and CD4 + and CD4 +/CD8 + were lower than before radiotherapy (both P < 0.05). The levels of IL-6, TNF-α and CD8 + in the observation group were lower than those in the control group, while the CD4 + and CD4 +/CD8 + were higher than those in the control group (all P < 0.05). The 3-year local recurrence rate [34.04% (16/47) vs. 42.55% (20/47)], distant metastasis rate [25.53% (12/47) vs. 38.30% (18/47)] and mortality rate [14.89% (7/47) vs. 19.15% (9/47)] in the observation group were lower than those in the control group, but the differences were not statistically significant (all P > 0.05). Conclusion:Compared with 3DCRT, the Hy-IMRT has less effect on the immune function of locally advanced breast cancer patients after modified radical resection, and the incidences of acute skin reaction and bone marrow adverse reaction are low.