Nixon A J, Manola J, Gelman R, Bornstein B, Abner A, Hetelekidis S, Recht A, Harris J R
Joint Center for Radiation Therapy and the Division of Biostatistics, Harvard Medical School, Boston, MA 02215, USA.
J Clin Oncol. 1998 Apr;16(4):1374-9. doi: 10.1200/JCO.1998.16.4.1374.
To determine whether left-breast irradiation using modern techniques after breast-conserving surgery leads to an increased risk of cardiac-related mortality.
Between 1968 and 1986, 1,624 patients were treated for unilateral stage I or II breast cancer at the Joint Center for Radiation Therapy, Harvard Medical School, Boston, MA, with conservative surgery and breast irradiation. Seven hundred forty-five patients with a potential follow-up of at least 12 years were analyzed. Clinical, pathologic, and treatment characteristics were compared between the 365 patients (49%) who received left-sided irradiation and the 380 patients (51%) who received right-sided irradiation. The relationship between left-sided breast irradiation and the risk of nonbreast cancer- and cardiac-related mortality was examined.
There was no significant difference in the distribution of clinical, pathologic, or treatment characteristics between the two groups, with the exception of a small difference in pathologic tumor size (medians, left, 2.0 cm, right, 1.5 cm; P = .007). At 12 years, a majority of patients still were alive. Slightly more patients with left-sided tumors had died of breast cancer (31% v 27%; P = NS). Equivalent proportions from each group died of nonbreast cancer causes (11%), including nine patients (2%) from each group who died from cardiac causes. The risk of cardiac mortality did not increase as time after treatment increased for patients who received left-sided irradiation compared with right-sided irradiation. A model that controlled for clinical, pathologic, and treatment differences showed no significant increase in any category of cause of death (breast, cardiac, or other) for patients who received left-sided irradiation.
These results suggest that modern breast radiotherapy is not associated with an increased risk of cardiac-related mortality within at least the first 12 years after treatment.
确定保乳手术后采用现代技术进行左侧乳房照射是否会增加心脏相关死亡率。
1968年至1986年间，1624例单侧I期或II期乳腺癌患者在马萨诸塞州波士顿哈佛医学院联合放射治疗中心接受了保乳手术及乳房照射治疗。对745例可能随访至少12年的患者进行了分析。比较了接受左侧照射的365例患者（49%）和接受右侧照射的380例患者（51%）的临床、病理和治疗特征。研究了左侧乳房照射与非乳腺癌及心脏相关死亡率之间的关系。
两组在临床、病理或治疗特征分布上无显著差异，但病理肿瘤大小存在微小差异（中位数，左侧2.0 cm，右侧1.5 cm；P = 0.007）。12年时，大多数患者仍存活。左侧肿瘤患者死于乳腺癌的比例略高（31%对27%；P = 无统计学意义）。两组死于非乳腺癌原因的比例相当（11%），每组各有9例患者（2%）死于心脏原因。与右侧照射的患者相比，接受左侧照射的患者心脏死亡率并未随治疗后时间的增加而升高。一个控制了临床、病理和治疗差异的模型显示，接受左侧照射的患者在任何死因类别（乳腺癌、心脏或其他）上均无显著增加。
这些结果表明，现代乳房放疗在治疗后的至少前12年内与心脏相关死亡率增加无关。
