Table 1.

Characteristics of the 393 evaluated patients and 396 treated breasts

Characteristic	N	%
Age (years)
Mean (± standard deviation)	63.9 (± 10.8)
Median	63.7
Range	34 to 91
BMI [kg/m 2 ]
Mean (± standard deviation)	28.2 (± 5.3)
Median	27.6
Range	15.4 to 56.0
Comorbidities
Diabetes mellitus	85	21.6
Arterial hypertension	215	54.7
Smoker	90	22.9
Breast side
Right	213	54.2
Left	177	45.0
Bilateral	3	0.8
Histology *
Ductal carcinoma in situ	20	5.1
Invasive carcinoma	324	81.8
Invasive lobular carcinoma	20	5.1
Others	32	8.1
Estrogen receptor positive*	349	88.1
Progesterone receptor positive*	306	77.3
HER-2 Positive*	22	5.6
Luminal A or B “like”*	338	85.4
Triple negative*	36	9.1
Clinical stage (AJCC 7 th ed) *
0	23	5.8
I–IIA	235	59.4
IIB–IIIB	138	34.8
Surgery *
Conservative	375	94.7
Nipple-sparing mastectomy	4	1.0
Modified radical mastectomy	17	4.3
Breast reconstruction	6	1.5
Pathological stage (AJCC 7 th ed) *
0	22	5.6
I–IIA	339	85.6
IIB–IIIB	35	8.8
pT stage *
pTis	22	5.6
pT0–T2	367	92.6
pT3–T4	7	1.8
pN stage *
pN0	331	83.6
pN1mi	26	6.6
pN1a	34	8.6
pN2a	4	1.0
pN3a	1	0.2
Chemotherapy
None	228	58.0
Neoadjuvant	16	4.1
Adjuvant	149	37.9
Hormone therapy	344	87.5
Radiotherapy fractionation
15 fractions	161	40.6
16 fractions	147	37.1
17 fractions	88	22.3
Additional radiotherapy fields *
Supraclavicular/axillary	13	3.3
Internal mammary	1	0.3
Boost	110	27.8
Tangential fields separation [cm] *
Mean (± standard deviation)	18.0 (± 2.9)
Median	17.8
Range	8.5 to 27.0
PTV [cc] *
Mean (± standard deviation)	915.6 (± 368.5)
Median	868.8
Range	211.9 to 2402.8

N — number; BMI — body mass index; PTV — planning target volume;

^*Data regarding the number of treated breasts