Ossifying fibromyxoid tumor: a study of 6 cases of atypical and malignant variants.
Ossifying fibromyxoid tumors (OFMT) of soft parts are rare, slow-growing tumors that have potential for local recurrence and may metastasize. While OFMT originally was considered benign, several cases of malignant OFMT have been documented. There is no universally accepted risk stratification, although this study emphasizes the importance of utilizing histology, immunohistochemistry and FISH in establishing the diagnosis. Herein, we describe six cases of atypical and malignant OFMT with differences in morphologic features, 5 of which display the proposed morphological criteria for malignancy. The patients were mostly male (M=5, F=1) with an age range of 33-69 years. The tumors arose from the extremities (3 cases), the shoulder (1 case), the head and neck area (1 case), and the paraspinal area (1 case). One tumor had high grade and overtly sarcomatous changes, while another invaded the underlying clavicle. Two cases showed cytological atypia and necrosis. Fluorescence in situ hybridization (FISH) detected rearrangement of the PHF1 gene in 5 cases. All cases were positive for EAAT4 and actin by immunohistochemistry, while negative for desmin. Three tumors were immunoreactive for S100 protein. INI-1 immunohistochemical staining was conserved in all but 2 cases in which a mosaic loss of expression was noted. All but two patients are currently alive and free of disease.
Department of Pathology Presbyterian Shadyside Hospitals, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA.
Kossivi
K
Dantey
Department of Pathology Presbyterian Shadyside Hospitals, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA.
Karen
K
Schoedel
Department of Pathology Presbyterian Shadyside Hospitals, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA.
Oleksandr
O
Yergiyev
Department of Orthopaedic Surgery, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA.
Richard
R
McGough
Department of Pathology Presbyterian Shadyside Hospitals, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA.
Alka
A
Palekar
Department of Pathology Presbyterian Shadyside Hospitals, University of Pittsburgh Medical center, 5230 Centre Avenue, Pittsburgh, PA, 15232, USA. Electronic address: raounm@upmc.edu.
Uma N M
UNM
Rao
D000199:Actins / Q000032:analysis; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D001706:Biopsy; D001859:Bone Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D004268:DNA-Binding Proteins / Q000235:genetics; D018572:Disease-Free Survival; D050581:Excitatory Amino Acid Transporter 4 / Q000032:analysis; D005260:Female; D018214:Fibroma, Ossifying / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D015321:Gene Rearrangement; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D063146:Polycomb-Group Proteins / Q000235:genetics; D009418:S100 Proteins / Q000032:analysis; D000071796:SMARCB1 Protein / Q000032:analysis; D013997:Time Factors; D016896:Treatment Outcome
D000199:Actins; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D050581:Excitatory Amino Acid Transporter 4; C112309:PHF1 protein, human; D063146:Polycomb-Group Proteins; D009418:S100 Proteins; C493391:SLC1A6 protein, human; D000071796:SMARCB1 Protein; C513266:SMARCB1 protein, human
EEAT4; Fibrosarcoma; Malignant; Ossifying fibromyxoid tumor; PHF1 gene