Specific but variable expression of h-caldesmon in leiomyosarcomas: an immunohistochemical reassessment of a novel myogenic marker.
h-Caldesmon is considered a novel specific marker for tumors with smooth muscle differentiation. To reassess its diagnostic use, the authors evaluated the immunohistochemical expression of h-caldesmon and other myogenic markers (calponin, alpha-smooth muscle actin, HHF35, and desmin) in 30 leiomyosarcomas (external soft tissues [15], retroperitoneum [8], uterus [5], other sites [2]), 26 myofibroblastic lesions, and 26 fibrohistiocytic tumors of varying biologic potential and histology. In contrast with previous data, h-caldesmon was expressed only in 11 (36%) of the 30 leiomyosarcomas analyzed, whereas they consistently expressed actins and frequently expressed calponin (86%) and desmin (76%). Leiomyosarcomas with the expression of h-caldesmon were well or moderately differentiated and primarily confined to the retroperitoneum or uterus. All but one leiomyosarcomas in the external soft tissues examined were negative for h-caldesmon, and the h-caldesmon-negative tumors showed moderately to poorly differentiated morphology. All myofibroblastic lesions examined were negative for h-caldesmon despite their constant expressions of at least one of the other markers. h-Caldesmon was not expressed in fibrohistiocytic tumors either, although focal positivity for the other markers was seen in subsets of the tumors. Thus, h-caldesmon can be regarded as a specific myogenic marker. However, one should be aware that the expression of h-caldesmon in leiomyosarcomas can be more variable according to their locations and/or extent of smooth muscle differentiation than considered previously.
Hisaoka
M
M
Department of Pathology and Oncology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Wei-Qi
S
S
Jian
W
W
Morio
T
T
Hashimoto
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007890:Leiomyosarcoma / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000737:chemistry; D009363:Neoplasm Proteins / Q000378:metabolism*; D009379:Neoplasms, Muscle Tissue / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology
D014408:Biomarkers, Tumor; D002148:Calmodulin-Binding Proteins; D009363:Neoplasm Proteins