Table 1.

Clinicopathologic, immunophenotypic, and molecular findings of the study cohort.

	Age/Sex	Location	Cytologic features	Myogenin	MyoD1	Desmin	CK AE1/3	ALK IHC	Molecular alterations	Metastasis	Outcome
1	22/M	Mandible	Spindle & epithelioid	Pos (focal)	Pos	Pos (focal)	Pos	Pos	FUS-TFCP2 ALK: WT	Lymph node	NA
2	34/M	Mandible	Spindle, epithelioid & rhabdoid	NA	Pos (patchy)	Pos	Neg	Neg	FUS-TFCP2 ALK deletion (exons 2-17)	No	AWD (10m)
3	16/M	Mandible	Spindle, epithelioid, & rhabdoid	Pos (focal)	Pos (focal)	Pos (focal)	Pos	Pos	FUS-TFCP2 ALK deletion (exons 2-19)	Bone, lung, lymph node	DOD (20m)
4	43/F	Mandible	Spindle & epithelioid	Pos (rare cells)	Pos	Pos	Pos	Pos	FUS-TFCP2 ALK: ND	NA	NA
5*	20/F	Maxilla	Spindle & epithelioid	Pos	NA	Pos (focal)	Pos	Pos	EWSR1-TFCP2 ALK: ND	Bone	NA
6*	33/F	Maxilla	Spindle & epithelioid	Pos	Pos	Pos (focal)	Pos	Pos	EWSR1-TFCP2 ALK: ND	NA	NED (108m)
7*	74/F	Maxilla/gingiva	Spindle & epithelioid	Pos (focal)	Pos (patchy)	Pos	Neg	Pos	FUS-TFCP2 ALK: WT	Lymph node	DOD (21m)
8*	27/F	Skull	Spindle & epithelioid	Pos (focal)	Pos	Pos	Pos	Pos	EWSR1-TFCP2 ALK: ND	Bone	AWD (1m)
9	18/M	Skull	Spindle & epithelioid	Neg	NA	Neg	Pos	Pos	FUS-TFCP2 ALK: WT	NA	NA
10	29/M	Skull (base)	Spindle & epithelioid	Pos	Pos	Pos	Pos	NA	EWSR1-TFCP2 ALK: WT	Lung	AWD (2m)
11	40/F	Neck superficial soft tissue	Spindle, epithelioid & round	Pos (rare cells)	NA	Pos	Pos	Pos	FUS-TFCP2 ALK deletion (introns 1-16)	NA	NA

NA: not available, Pos: positive, Neg: negative, NED: no evidence of disease, AWD: alive with disease, IHC: immunohistochemistry m: months, WT: wild type, ND: not done.

^*Cases 5 to 8 were reported previously ^{5, 9}.