Table 3.

Associations between MHD, V5, and V30 and biomarker levels after completion of RT in breast cancer and lung cancer/lymphoma

Biomarker	Breast cancer						Lung cancer/Mediastinal lymphoma
	MHD		V5		V30		MHD		V5		V30
	Beta (95% CI)	P value	Beta (95% CI)	P value	Beta (95% CI)	P value	Beta (95% CI)	P value	Beta (95% CI)	P value	Beta (95% CI)	P value
hs-cTnT	0.14 (0–0.28)	.052	0.12 (−0.01 to 0.25)	.061	0.09 (−0.01 to 0.19)	.071	0.07 (−0.22 to 0.37)	.606	0.05 (−0.25 to 0.35)	.737	0.10 (−0.26 to 0.46)	.561
NT-proBNP	−0.01 (−0.20 to 0.19)	.956	0 (−0.18 to 0.18)	.997	0.05 (−0.09 to 0.19)	.444	−0.14 (−0.56 to 0.27)	.476	−0.18 (−0.61 to 0.24)	.374	−0.09 (−0.60 to 0.41)	.703
PIGF	0.01 (−0.06 to 0.08)	.846	0.02 (−0.04 to 0.08)	.533	0.01 (−0.04 to 0.06)	.734	0.15 (0–0.30)	.050	0.21 (0.06–0.35)	.008	0.14 (−0.06 to 0.34)	.155
GDF-15	0.07 (−0.03 to 0.16)	.176	0.07 (−0.01 to 0.16)	.091	0.01 (−0.06 to 0.08)	.808	0.40 (0.14–0.66)	.005	0.37 (0.10–0.65)	.011	0.46 (0.13–0.79)	.008

Abbreviations: CI = confidence interval; GDF-15 = growth differentiation factor 15; hs-cTnT = high-sensitivity cardiac troponin T; MHD = mean heart dose; NT-proBNP = N-terminal pro-B-type natriuretic peptide; PIGF = placental growth factor; RT = radiation therapy.

All biomarker variables were natural log-transformed. Per each interquartile range (i.e., 1.5 Gy for MHD, 6.8% for V5, and 0.9% for V30 in breast cancer; and 7.7 Gy for MHD, 27.9% for V5, and 18.4% for V30 in lung cancer/lymphoma) increase, the beta coefficient represents the percent change in biomarker value post-RT. Associations were adjusted for age, anthracycline or trastuzumab exposure, hypertension, diabetes mellitus, and pre-RT level of the biomarker under consideration.