Table 1 Patients’ characteristics and procedures of 1st and 2nd ASCT.

	Case 1	Case 2	Case 3	Case 4
Characteristics at the 1st ASCT
Age/sex	53/M	42/M	50/M	33/F
Induction therapy	HD-Dex	PSL, Td, Rd, Bd	None	Td
Time from diagnosis to 1st ASCT (months)	5	15	2	4
VEGF response	NRv	PRv	NRv	NRv
Hematologic response	NR_H	NR_H	NR_H	NR_H
Conditioning regimen of 1st ASCT	Mel 140	Mel 200	CY+ETP+MCNU	Mel 200
Infused CD34+ cells (×10⁶/kg)	4.5	3.59	Unknown	1.69
Responses after the 1st ASCT
VEGF response	CRv	CRv	CRv	CRv
Hematologic response	NR_H	NR_H	CR_H	NR_H
Clinical response	Yes	Yes	Yes	Yes
Time from 1st ASCT to relapse or progression (months)	9	7	85	11
Status of relapse or progression	VEGF	VEGF	VEGF	VEGF
	Clinical		Hematological
			Clinical
Salvage therapy	Td	Td, Rd, Bd	Td, Rd, CyBorD	Td
Characteristics at the 2nd ASCT
Age	55	44	57	39
Time from 1st to 2nd ASCT (months)	25	21	125	55
VEGF response	PRv	CRv	PRv	PRv
Hemaological response	NR_H	CR_H	NR_H	NR_H
Conditioning regimen	Mel 200	Mel 200	Mel 200	Mel 200
Infused CD34+ cells (×10⁶/kg)	2.37	2.69	2.47	1.49
Responses and outcomes after the 2nd ASCT
VEGF response	CRv	CRv	CRv	CRv
Hematological response	CR_H	CR_H	CR_H	CR_H
Clinical response	Yes	-	Yes	–
Treatment-free period from 2nd ASCT (months)	10	25	46	36
Relapse or progression	Yes	Yes	Yes	No
Status of relapse or progression	VEGF	VEGF	VEGF	–
	Hematological	Hematological	Hematological
		Clinical
Salvage therapy	Td, Rd	Td, Bd	IRd, 3rd ASCT	None
Last follow up from 2nd ASCT (months)	102	52	66	36
Outcome	Alive	Dead (progression)	Alive	Alive

CRv complete VEGF response, PRv partial VEGF reponse, NRv no VEGF response, CRH complete hematological response, NRH no complete hematological response, FN febrile neutropenia, HD-DEX high-dose dexamethasone, Td thalidomide and dexamethasone, Rd lenalidomide and dexamethasone, Bd bortezomib and dexamethasone, CyBorD cyclophosphamide, bortezomib, and dexamethasone, Mel 140 melphalan 140 mg/m², Mel 200 melphalan 200 mg/m², CY cyclophosphamide, ETP etoposide, MCNU ranimustine, IRd ixazomib, lenalidomide and dexamethasone.

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