Fluorescence In Situ Hybridization for MDM2 Amplification as a Routine Ancillary Diagnostic Tool for Suspected Well-Differentiated and Dedifferentiated Liposarcomas: Experience at a Tertiary Center

Table 2

Comparison of histological tumor type and FISH results.

Histological diagnosis	Total	MDM+	MDM−	MDM2−, with multiple copies of CEP12 and MDM2 signals
Benign	122	9	113	20
Lipoma	76	4	72	9
Intramuscular lipoma	12	2	10	0
Spindle cell lipoma	17	0	17	5
Pleomorphic lipoma	9	2	7	5
Fat necrosis	2	0	2	0
Lipoblastoma	2	0	2	0
Lipoleiomyoma	1	0	1	1
Hibernoma	1	0	1	0
Nevus lipomatosis	1	0	1	0
Fibroadipose tissue/scar	2	1	1	0
Liposarcoma	145	137	8	10
WDL	73	71	2	5
DDL	69	66	3	3
Myxoid LPS	2	0	2	0
Pleomorphic LPS	1	0	1	2
Equivocal cases	34 (including 1 technical fail)	10	23	0
Possible WDL/DDL	19	6	13	0
Probable/suspected WDL/DDL	15	4	10	0
Other soft tissue sarcomas/malignancies	64 (including 2 technical fails)	14	48	26
Undifferentiated pleomorphic sarcoma	28	5	21	14
Spindle cell sarcoma (NOS)	19	2	17	8
Rhabdomyosarcoma	5	3	2	2
Solitary fibrous tumor	3	1	2	1
Leiomyosarcoma	3	1	2	1
Malignant peripheral nerve sheath tumor	2	1	1	0
Osteosarcoma	1	1	0	0
Inflammatory myofibroblastic tumor	1	0	1	0
Poorly differentiated carcinoma	2	0	2	0