Vertebral body collapse after spine stereotactic body radiation therapy: a single-center institutional experience

	Univariate analysis p-value
Gender	0.60
Age (≥ 68 vs. < 67)	0.89
KPS (≥ 80 vs. < 80)	0.38
Spine level (cervical v.s thoracic)	0.74
Spine Level (cervical vs. lumbosacral)	0.48
Spine Level (thoracic vs. lumbosacral)	0.53
Paraspinal extension	1.00
Dose per fraction (< 9 Gy v.s ≥ 9 Gy)	0.43
Location (rigid/semi-rigid vs mobile/junctional spine)	0.79
Mechanical pain	0.79
Lytic vs non-lytic bone lesion	0.93
Spinal alignment (normal vs. kyphosis/scoliosis)	0.96
Posterolateral involvement	0.29

	VBC (n=10)	%	No VBC (n = 90)	%	Total (n = 100)	%
Location
Junctional (O-C2; C7−T2; T11−L1; L5−S1)	3	30%	32	36%	35	35%
Mobile spine (C3−6; L2−4)	3	30%	18	20%	21	21%
Semirigid (T3−10)	4	40%	40	44%	44	44%
Rigid (S2−5)	0	0%	0	0%	0	0%
Mechanical pain
Yes	5	50%	49	54%	54	54%
No	3	30%	30	33%	33	33%
Pain-free lesion	2	20%	11	12%	13	13%
Bone lesion
Lytic	8	80%	71	79%	79	79%
Mixed (lytic/blastic)	1	10%	9	10%	10	10%
Blastic	1	10%	10	11%	11	11%
Radiographic spinal alignment
Subluxation/translation present	0	0%	8	9%	8	8%
Deformity (kyphosis/scoliosis)	2	20%	17	19%	19	19%
Normal	8	80%	65	72%	73	73%
Vertebral body collapse (p = 0.040)
> 50% collapse	0	0%	9	10%	9	9%
< 50% collapse	1	10%	8	9%	9	9%
No collapse with > 50% body involved	1	10%	38	42%	39	39%
None of the above	8	80%	35	39%	43	43%
Posterolateral involvement
Bilateral	0	0%	5	6%	5	5%
Unilateral	6	60%	33	37%	39	39%
None of the above	4	40%	52	58%	56	56%
SINS classification
Stable	4	40%	22	24%	26	26%
Potentially instability	6	60%	63	70%	69	69%
Unstable	0	0%	5	6%	5	5%

	VBC (N = 10)	%	No VBC (N = 90)	%	Total (N = 100)	%
Median follow up, month (IQR) (n = 100)	10.9	3.9–18.6	12.5	5.1–27.2	12.1	5.0–25.5
Sex (n = 83)*
Male	5	56%	37	50%	42	51%
Female	4	44%	37	50%	41	49%
Median age, year (IQR) (n = 83)*	67	63–70	69	59–75	68	59–74
Race (n = 83)
White	8	89%	69	93%	77	93%
Black	2	22%	1	1%	3	4%
Other/unknown	0	0%	3	4%	3	4%
KPS (n = 83)*
≥ 80	9	90%	70	95%	79	95%
< 80	1	10%	3	4%	4	5%
Primary tumor (n = 100)**
Lung	4	40%	25	28%	29	29%
Renal	1	10%	23	26%	24	24%
Breast	1	10%	8	9%	9	9%
Prostate	2	20%	10	11%	12	12%
Melanoma	0	0%	2	2%	2	2%
Other	2	20%	22	24%	24	24%
Spine Level (n = 100)**
Cervical	1	10%	14	16%	15	15%
Thoracic	6	60%	58	64%	64	64%
Lumbosacral	3	30%	18	20%	21	21%
Kyphoplasty pre-SBRT (n = 100)**
Yes	0	0%	11	12%	11	11%
No	10	100%	79	88%	89	89%
Paraspinal extension (n = 100)**
Yes	4	40%	36	40%	40	40%
No	6	60%	54	60%	60	60%
Total dose (Gy)/fractions (n = 100)**
12−17/1	1	10%	12	13%	13	13%
10−24/2	0	0%	2	2%	2	2%
15−30/3	8	80%	61	68%	69	69%
20-30/4–5	1	10%	15	17%	16	16%
Dose (Gy) per fraction (n = 100)**
< 8	4	40%	31	34%	35	35%
8−12	5	50%	50	56%	55	55%
13−17	1	10%	9	10%	10	10%

Publication timeframe:: 4 times per year
Journal Subjects:: Medicine, Clinical Medicine, Internal Medicine, Haematology, Oncology, Radiology