Table 3.

Summary of anatomic lung dose-volume parameters in patients that experienced greater than ("Deteriorating FEV1") and less than ("Stable FEV1") the median percentage decline in FEV1 at different radiotherapy dose thresholds (V5-50) and for MLD

% Anatomic volume	"‘Stable FEV1" (n = 21)	"‘Deteriorating FEV1" (n = 20)	Difference between means (%)	t-test p-value	ROC AUC (Az)
V5	39.6	47.4	7.9	0.093	0.66
V10	25.9	36.7	10.8	0.005**	0.77
V13	20.8	30.1	9.3	0.005**	0.76
V20	14.5	19.5	5.1	0.025	0.70
V30	9.9	12.4	2.5	0.129	0.65
V40	6.4	7.6	1.2	0.313	0.61
V50	2.7	3.5	0.8	0.211	0.66
MLD (cGy)	897	1127	229	0.040	0.69

AUC, area under the curve; MLD, mean lung dose; ROC, receiver operating characteristic.

Results that reach statistical significance after applying the Bonferroni correction (significance level 0.05/8 = 0.00625) are marked**.