Genetic Variability of Antioxidative Mechanisms and Cardiotoxicity after Adjuvant Radiotherapy in HER2-Positive Breast Cancer Patients

Table 1

Characteristics of breast cancer patients included in the study () and treatment parameters.

Characteristic	Category/Unit	(%)
Age	Years	50.9 (42.1-59.1)
Type of surgery	Mastectomy	48 (47.5)
	Conservative surgery	53 (52.5)
Side of surgery	Left	48 (47.5)
	Right	53 (52.5)
Tumour type	Invasive lobular carcinoma	2 (2.0)
	Invasive ductal carcinoma	96 (95.0)
	Other	3 (3.0)
Cancer grade	1	1 (1.0)
	2	31 (30.7)
	3	69 (68.3)
Chemotherapy scheme	AC/EC/FAC/FEC with taxanes	54 (53.5)
	AC/EC/FAC/FEC without taxanes	43 (42.6)
	Other	4 (4.0)
Anthracyclines	Yes	99 (98.0)
	Doxorubicin	6 (6.0)
	Epirubicin	93 (92.1)
	No	2 (2.0)
Anthracyclines cumulative dose	Doxorubicin, mg/m^2 BSA	342 (318-413)
	Epirubicin, mg/m^2 BSA	353 (294-522)
Taxanes	Yes	58 (57.4)
	Paclitaxel	17 (16.7)
	Docetaxel	41 (40.6)
	No	43 (42.6)
Taxanes cumulative dose	Paclitaxel, mg/m^2 BSA	886 (739-938)
	Docetaxel, mg/m^2 BSA	286 (269-299)
Hormonal therapy	Yes	57 (56.4)
	No	44 (43.6)
Treatment scheme of RT		84 (83.2)
		17 (16.8)
Site of RT	Breast/mammary region	58 (57.4)
	(Breast/mammary region) + regional lymph nodes	43 (42.6)
RT technique	2D RT	80 (79.2)
	3D CRT	14 (13.9)
	Electrons	7 (6.9)
Hypertension	Yes	29 (28.7)
	No	72 (71.3)
Hyperlipidemia	Yes	21 (20.8)
	No	80 (79.2)
Smoking	Yes	16 (15.8)
	No	85 (84.2)
Diabetes	Yes	1 (1.0)
	No	100 (99.0)
Body mass index	kg/m^2	27.1 (24.3-29.7)

median (25%-75%). 2D RT: two-dimensional radiotherapy; 3D CRT: three-dimensional conformal radiotherapy; AC: doxorubicin, cyclophosphamide; BSA: body surface area calculated according to the Du Bois formula; EC: epirubicin, cyclophosphamide; FAC: 5-fluorouracil, doxorubicin, cyclophosphamide; FEC: 5-fluorouracil, epirubicin, and cyclophosphamide; Gy: Gray; RT: radiotherapy.