Effect of tandem autologous stem cell transplantation on survival in pediatric patients with high-risk solid tumors in South China

Table 1 Patient characteristics, n (%)

Characteristics	Group A (n = 21)	Group B (n = 19)	Total (n = 40)	P value
Age				0.03a
< 36 months	5 (23.8)	14 (73.7)	19 (47.5)
≥ 36 months	16 (76.2)	5 (26.3)	21 (52.5)
Sex				0.19
Male	15 (71.4)	14 (73.7)	29 (75)
Female	6 (28.6)	5 (26.3)	11 (25)
Diagnosis				0.84
Neuroblastoma	18 (85.7)	17 (89.4)	35 (87.5)
Germ cell tumor	2 (9.5)	0 (0)	2 (5.0)
ATRT	1 (4.8)	0 (0)	1 (2.5)
Medulloblastoma	0 (0)	1 (5.3)	1 (2.5)
Pineoblastoma	0 (0)	1 (5.3)	1 (2.5)
Primary site				0.10
Abdomen	15 (71.4)	15 (79.0)	30 (75.0)
Mediastinum	4 (19.0)	2 (10.5)	6 (15.00)
Testis	1 (4.8)	0 (0)	1 (2.5)
Central nervous system	1 (4.8)	2 (10.5)	3 (7.5)
LDH at diagnosis				0.02a
< 1000 U/L	18 (85.7)	13 (68.4)	31 (77.5)
≥ 1000 U/L	3 (14.3)	6 (31.6)	9 (22.5)
No. of chemotherapy cycles before HDCT				0.72
≤ 8 cycles	4 (19.0)	1 (5.3)	5 (12.5)
≥ 9 cycles	17 (81.0)	18 (94.7)	35 (87.5)
Bone marrow metastasis				0.08
Negative	9 (42.9)	8 (42.1)	17 (42.5)
Positive	12 (57.1)	11 (57.9)	23 (57.5)
No. of metastasized organs				0.67
1-2	6 (28.6)	6 (31.6)	12 (30.0)
≥ 3	15 (71.4)	13 (68.4)	28 (70.0)

^aP < 0.05.

ATRT: Atypical teratoid/rhabdoid tumor; LDH: Lactate dehydrogenase; HDCT: High-dose chemotherapy.

Table 2 Univariable analysis of 35 pediatric patients with high-risk neuroblastoma, n (%)

Characteristics	Total (n = 35)	3-year OS			3-year EFS
		mean ± SD	χ2	P value	mean ± SD	χ2	P value
Age
< 36 months	10 (28.6)	100			100
≥ 36 months	25 (71.4)	55.4 ± 12.2	4.85	0.03a	51.3 ± 12.0	4.85	0.03a
Sex
Male	26 (74.3)	71.8 ± 10.5			67.9 ± 10.7
Female	9 (25.7)	57.1 ± 18.7	0.37	0.54	57.1 ± 18.7	1.7	0.36
LDH
< 1000 U/L	25 (71.4)	82.0 ± 8.1			77.4 ± 8.9
≥ 1000 U/L	10 (28.6)	30.0 ± 22.6	4.32	0.04a	30.0 ± 22.6	3.15	0.08
MYCN
Non-amplified	23 (65.7)	62.4 ± 14.0			57.9 ± 13.7
Amplified	5 (14.3)	100			100
Unknown	7 (20.0)	57.1 ± 18.7	2.72	0.10	57.1 ± 18.7	2.43	0.12
NSE
< 200 ng/mL	10 (28.6)	70.0 ± 14.5			70.0 ± 14.5
≥ 200 ng/mL	21 (60.0)	68.8 ± 14.8			63.7 ± 14.5
Unknown	4 (11.4)	50.0 ± 25.0	0.12	0.73	50.0 ± 25.0	0.19	0.66

^aP < 0.05.

OS: Overall survival; EFS: Event-free survival; LDH: Lactate dehydrogenase; NSE: Neuron-specific enolase.

Table 3 Toxicity in patients with solid tumors who underwent tandem autologous stem cell transplantation, n (%)

Parameter	First ASCT		Second ASCT
	Group A (n = 21)	Group B (n = 19)	Group A (n = 21)	Group B (n = 19)
Hematologic toxicity
Fever (BT ≥ 38.0 °C)	17 (81.1)	18 (94.7)	17 (80.1)	16 (84.2)
Septicemia	2 (9.5)	1 (5.3)	0 (0)	0 (0)
Non-hematologic toxicity
Mucositis	1 (4.8)	3 (15.8)	2 (9.5)	5 (26.3)
Vomiting	14 (66.7)	16 (84.2)	12 (57.1)	11 (57.9)
Diarrhea	10 (47.6)	13 (68.4)	10 (47.6)	11 (57.9)
Elevated liver enzymes	4 (19.0)	4 (21.1)	1 (4.7)	4 (21.1)
Renal insufficiency	0 (0)	1 (5.3)	0 (0)	1 (5.3)
Hypokalemia	5 (23.8)	10 (52.6)	2 (9.5)	4 (21.1)
Hypomagnesemia	8 (38.0)	6 (31.6)	7 (33.3)	2 (10.5)
Hepatic VOD	0 (0)	0 (0)	0 (0)	3 (15.8)
Myocarditis	2 (9.5)	1 (5.3)	0 (0)	0 (0)
Treatment-related mortality	0		0

ASCT: Autologous stem cell transplantation; BT: Body temperature; VOD: Veno-occlusive disease.