Calponin and h-caldesmon expression in atypical fibroxanthoma and superficial leiomyosarcoma.
To evaluate smooth muscle differentiation, myogenic markers [desmin, alpha-smooth muscle actin (SMA), and muscle-specific actin (HHF35)] have been widely used. Calponin and h-caldesmon, which are cytoskeleton-associated actin-binding proteins, have been reported to be more specific myogenic markers, especially since myofibroblasts express a small amount of h-caldesmon. Atypical fibroxanthoma (AFX) occurs in the sun-exposed skin of the elderly and follows a benign clinical course. Histologically, AFX, which is a pleomorphic spindle cell tumor and considered to be a superficial variant of malignant fibrous histiocytoma, also mimics leiomyosarcoma. AFX has been thought to differentiate along pathways with fibrohistiocytic and myofibroblastic phenotypes. AFX ( n=10), superficial leiomyosarcoma (S-LMS) ( n=17) and benign fibrous histiocytoma (BFH) ( n=17) were analyzed for myofibroblastic and smooth muscle differentiation immunohistochemically from the viewpoint of comparison. AFX and BFH showed immunoreactivities respectively for calponin (3/10, 11/17), desmin (3/10, 1/17), SMA (3/10, 13/17), and HHF35 (1/10, 5/17), but failed to express h-caldesmon (0/10, 0/17). S-LMS had a high immunoreactive rate of calponin (17/17), desmin (13/17), SMA (16/17), and HHF35 (16/17), while also expressing caldesmon (11/17). The results reveal that AFX and BFH have immunoreactivities for several myogenic markers, with myofibroblastic differentiation (calponin: +/-, h-caldesmon: -), but without the smooth muscle differentiation seen in S-LMS (calponin:+, h-caldesmon: +/-). In addition, calponin and h-caldesmon are considered to be useful markers for distinguishing AFX from S-LMS.
Sakamoto
A
A
Department of Anatomic Pathology, Pathological Sciences, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Oda
Y
Y
Yamamoto
H
H
Oshiro
Y
Y
Miyajima
K
K
Itakura
E
E
Tamiya
S
S
Honda
Y
Y
Ishihara
A
A
Iwamoto
Y
Y
Tsuneyoshi
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D034961:Antigens, Nuclear; D014408:Biomarkers, Tumor / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D018219:Histiocytoma, Benign Fibrous / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism; D007890:Leiomyosarcoma / Q000378:metabolism* / Q000473:pathology; D008840:Microfilament Proteins; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology; D000096985:Calponins
D034961:Antigens, Nuclear; D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D002148:Calmodulin-Binding Proteins; D019394:Ki-67 Antigen; D008840:Microfilament Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D000096985:Calponins