Prescreening based on the presence of CT-scan abnormalities and biomarkers (KL-6 and SP-D) may reduce severe radiation pneumonitis after stereotactic radiotherapy

Table 3 Relationship between G4-5 RP and pre-SBRT factors

Pre-SBRT factors	G4-5 RP	G0-3 RP	Total	X2 test	1-year cumulative incidence of G4-5 RP	log-rank
Serum KL-6
high value	6	17	23	p = 0.0002	32%	p < 0.0001
within normal level	2	78	80		3%
not available	1	13	14
Serum SP-D
high value	5	14	19	p = 0.0002	29%	p = 0.0001
within normal level	2	79	81		3%
not available	2	15	17
IP shadow in CT
(+)	7	6	13	p < 0.0001	57%	p < 0.0001
(-)	2	102	104		2%

ISSN: 1748-717X