Low-grade myofibrosarcoma of the maxillary sinus: Two case reports

Table 1 Comparison of immunohistochemical results in Cases 1 and 2

Case	Vimentin	SMA	CK AE 1/3	Desmin	h-Caldesmon	CD 34	S100 protein	EMA	ALK 1
1	+	+	-/+	-	-/+ trace	-	-	-/+	-
2	+	+	-	-	-	-	-	-	-

+: Positive reaction; -: Negative reaction. ALK 1: Anaplastic lymphoma kinase 1; CD 34: Cluster of differentiation 34; CKAE 1/3: Cytokeratin AE1 and AE3; EMA: Epithelial membrane antigen; SMA: Smooth muscle actin.

Table 2 Clinical features of reported cases of low-grade myofibrosarcomas of the maxillary

Ref.	Age	Sex	Size in cm	Side	Main symptoms	Necrosis	Mitotic rate, 10/10 HPF scale	Follow up in months	IHC	Results
Meng et al[7], 2007	33	F	6.5	Left	Nasal obstruction and leakage	Yes	10/10/HPF	12	Vimentin (+); SMA (+); Fibronectin (+); Calponin (+); Desmin (-); h-Caldesmon (-); Laminin (-); Type IV collagen (-); CD34 (-); CD68 (-); ALK1 (-)	Diagnostic testing of 1 yr
Meng et al[7], 2007	28	F	3	Left	Nasal obstruction and leakage	Yes	8/10 HPF	21	Vimentin (+); SMA (+); Fibronectin (+); Calponin (+); Desmin (-); h-Caldesmon (-); Laminin (-); Type IV collagen (-); CD34 (-); CD68 (-); ALK 1 (-)	Recurrent at 0.5 yr
Ghosh et al[2], 2019	35	M	No data	Left	Exophthalmos	No data	< 2/10 HPF	72	α-SMA (+); MIC-2 (+); Desmin (-); CD 34 (-); S100 protein (-); Cytokeratin (-); EMA (-); Calponin (-); Bcl-2 (-)	Recurrent at 6 yr
Bisceglia et al[13], 2001	24	M	4	Left	Pain, swelling of the midface	No data	1/10HPF	40	Vimentin (+); α-SMA (+); MSA (+); CD34 (-); Desmin (-); S100 protein (-); Cytokeratin (-)	Observation 3 yr
Gómez-Oliveira et al[8], 2015	75	F	No data	Left	Pain, swelling	Yes	No data	12	Vimentin (+); SMA (+); CD10 (+); Cytokeratin (+); h-Caldesmon (+); Desmin (-); CD34 (-); ALK (-); EMA (-); S100 protein (-)	After 1 yr metastasis-left femur
Current article	46	M	8	Right	Pain, swelling of the midface, nasal obstruction and leakage	No	4/10HPF	15	SMA (+) in some cells; tram truck type reaction; CK AE1/3 (-/+) focal weak reaction; MUC4 (-); CD34 (-); Desmin (-); SOX10 (-); S100 (-); Ki-67 5%; hHf35 (-); EMA (-/+) trace; Caldesmon (-/+) trace; H3K27me3 (+) preserved expression; ALK (-); ROS1 (-); HMB45 (-) Melan-A (-); Myogenin (-); MyoD1 (-)	Observation 1.5 yr
Current article	45	M	8	Right	Exophthalmos, strabismus, visual impairment	No	4/10HPF	26	SMA (+); Desmin (-); CD34 (-); EMA (-); CKAE1/3 -; Caldesmon (-); MUC1 (-); S100 (-); ALK1 (-); STAT6 (+/-); B-catenin (-)	Recurrent

α-SMA: α-Smooth muscle actin; ALK: Anaplastic lymphoma kinase; ALK1: Anaplastic lymphoma kinase 1; Bcl-2: B-cell lymphoma 2; CD34: Cluster of differentiation 34; CD68: Cluster of differentiation 68; CKAE1/3: Cytokeratin AE1 and AE3; EMA: Epithelial membrane antigen; F: Female; H3K27me3: Trimethylation of lysine 27 on histone H3; HMB45: Human melanoma black-45; HPF: High power field; M: Male; MIC-2: Monoclonal intestinal cancer-2; MSA: Muscle specific actin; MUC1: Mucin 1; MUC4: Mucin 4; MyoD1: Myogenic differentiation 1; ROS1: Receptor tyrosine kinase 1; SMA: Smooth muscle actin; SOX10: Sex determining region Y-box 10; STAT6: Signal transducer and activator of transcription 6.