Non-random chromosomal deletion clustering at 20q in Waldenström macroglobulinemia

Figures & data

Table 1. Clinical features in Waldenström macroglobulinemia

No.	Age (years)/gender	Date of examination	Status	Percentage of lymphoplasma-cytoid cells (%) in bone marrow	Serum monoclonal IgM (mg/dl)	Myelodysplasia	Treatment
1	85/M	28 July 2004	At diagnosis	26	1362	No	MP
2	52/M	24 July 2004	At diagnosis	88	6765	No	R-CHOP/Mel-Dex
		9 December 2009	After chemotherapy	29·4	3766	No
3	75/M	24 March 2009	At diagnosis	30·8	6021	No	R-Flu
4	62/M	12 November 2009	At diagnosis	18·6	3420	No	None
5	63/F	15 July 2001	At diagnosis	27·6	3040	11·5% in neutrophils	Unknown*
6	73/F	14 October 2008	At diagnosis	66·2	2042	No	R
7	69/M	14 December 1998	At diagnosis	66	4360	No	VAD
		14 January 2003	After chemotherapy	29	3764	No
8	90/M	25 December 2003	At diagnosis	17	4775	No	Unknown*
9	54/F	27 February 1996	At diagnosis	19	8680	No	Mel

Note: MP, melpharan+prednisolone; R, rituximub; CHOP, cyclophosphamide+vincristine+doxorubicin+prednisolone; Mel, melphalan; Del, dexamethasone; Flu, Fludarabine; VAD, vincristine+doxorubicin+ dexamethasone; none, follow-up without treatment unkown*, transfer to another hospital.

*Unnkown: transfer to another hospital.

Table 2. Cytogenetic and fluorescence in situ hybridization of del(20q) in Waldenström macroglobulinemia

			FISH results (green: 20qter/red: 20q12) (%)
No.	Date of examination	Cytogenetic results [no. of cells examined]	2G2R	2G1R	2G	1R	2R	Pattern
1	28 July 2004	46,XY,del(20)(q11)[8]/46,XY[13]	27	15		18·5	28	B/C
2	24 July 2004	46,XY[10]	93					A
	9 December 2009	46,XY,del(20)(q11)[8]/46,XY[10]	51	40				B
3	24 March 2009	46,XY[21]	93·5					A
4	12 November 2009	45,X,−Y[18]/46,XY[3]	41			5	45	C
5	15 July 2001	46,XY[22]	97					A
6	14 October 2008	46,XY,del(6)(q12),add(11)(q23),−15,−16,+2mar[1]/46,XX[17]	90·5					A
7	14 December 1998	46,XY[10]	91·5					A
	14 January 2003	46,XY[20]	93·5					A
8	25 December 2003	45,X,� −Y[18]/46,XY[3]		87·5	6·5			B
9	27 February 1996	46,XY[20]	72·5	6	18			B

Note: FISH results of <5% change were considered to be non-specific and deleted from this table.

Patterns A, B, and C: see the text.

Figure 1. (A) An interphase cell with two green signals (pattern B: arrows) obtained from UPN 9. (B) An interphase cell with one red signals (pattern C: arrow) obtained from UPN 4. (C) A metaphase cell with two red signals on double del(20q) chromosomes without the presence of green signal obtained from UPN 4. (D) Schematic interpretation by FISH study on chromosome 20. The far-right portion indicates chromosome 20 with possible common deleted region in Waldenström macroglobulinemia. Solid vertical lines show possible deleted chromosome regions. 20q12(−)/20qter(+) indicates interstitial deletion of 20q12 but retention of 20qter: 20q12(+)/20qter(−) indicates deletion of 20qter but retention of the 20q12 locus. The region indicates the constant deleted region from distal to the 20q12 locus to proximal to the 20qter locus in four patients (UPNs 1, 4, 8, and 9).