Are the American Society for Radiation Oncology Guidelines Accurate Predictors of Recurrence in Early Stage Breast Cancer Patients Treated with Balloon-Based Brachytherapy?

Table 3

Factors associated with ipsilateral breast tumor recurrence.

Variable	Hazard ratio (95% CI)	𝑃
Age: ≥50 versus <50	0.63 (0.08–5.19)	0.67
Age: ≥60 versus <60	0.55 (0.13–2.32)	0.42
Tumor size: >2 cm versus ≤2 cm^a	2.20 (0.25–19.75)	0.48
Tumor type: ILC versus other	1.89 (0.23–15.41)	0.55
Tumor type: DCIS versus invasive cancer	1.61 (0.38–6.75)	0.52
ER status: negative versus positive^a	5.87 (0.97–35.34)	0.053
Margins: negative versus close/positive	7.63 (1.45–40.0)	0.016
Multifocality: yes versus no	2.36 (0.28–19.99)	0.43
LVI: present versus nonea,b	—	0.60
Nodal status: positive versus negativea,b	—	1.0

CI: confidence interval, ILC: invasive lobular carcinoma, DCIS: ductal carcinoma in situ, ER: estrogen receptor, and LVI: lymphovascular invasion.
aExcludes DCIS.
bCox proportional hazards model could not be performed due to lack of events.