| Autor: |
Puls F; Department of Clinical Pathology and Genetics, Sahlgrenska University Hospital, Gothenburg., Pillay N; Department of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital NHS Trust, Stanmore.; Research Department of Pathology, University College London Cancer Institute, London., Fagman H; Department of Clinical Pathology and Genetics, Sahlgrenska University Hospital, Gothenburg., Palin-Masreliez A; Department of Clinical Pathology and Genetics, Sahlgrenska University Hospital, Gothenburg., Amary F; Department of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital NHS Trust, Stanmore., Hansson M; Department of Clinical Pathology and Genetics, Sahlgrenska University Hospital, Gothenburg., Kindblom LG; Department of Clinical Pathology and Genetics, Sahlgrenska University Hospital, Gothenburg., McCulloch TA; Department of Histopathology, Nottingham City Hospital, Nottingham., Meligonis G; Department of Histopathology, Addenbrooke's Hospital, Cambridge., Muc R; Department of Histopathology, Heartlands Hospital, Birmingham., Rissler P; Department of Clinical Genetics and Pathology, University and Regional Laboratories, Skåne University Hospital, Lund University., Sumathi VP; Department of Musculoskeletal Pathology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, UK., Tirabosco R; Department of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital NHS Trust, Stanmore., Hofvander J; Department of Clinical Genetics, Lund University, Lund, Sweden., Magnusson L; Department of Clinical Genetics, Lund University, Lund, Sweden., Nilsson J; Department of Clinical Genetics, Lund University, Lund, Sweden., Flanagan AM; Department of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital NHS Trust, Stanmore.; Research Department of Pathology, University College London Cancer Institute, London., Mertens F; Department of Clinical Genetics and Pathology, University and Regional Laboratories, Skåne University Hospital, Lund University.; Department of Clinical Genetics, Lund University, Lund, Sweden. |
| Abstrakt: |
Gene fusion transcripts containing PRDM10 were recently identified in low-grade undifferentiated pleomorphic sarcomas (UPS). Here, we describe the morphologic and clinical features of 9 such tumors from 5 men and 4 women (age: 20 to 61 y). Three cases had previously been diagnosed as UPS, 3 as superficial CD34-positive fibroblastic tumor (SCD34FT), 2 as pleomorphic liposarcoma, and 1 as pleomorphic hyalinizing angiectatic tumor. The tumors were located in the superficial and deep soft tissues of the thigh/knee region (4 cases), shoulder (2 cases), foot, trunk, and perineum (1 case each) ranging in size from 1 to 6 cm. All showed poorly defined cellular fascicles of pleomorphic cells within a fibrous stroma with frequent myxoid change and a prominent inflammatory infiltrate. All displayed highly pleomorphic nuclear features, but a low mitotic count. Most tumors were well circumscribed. One of 9 tumors recurred locally, but none metastasized. Immunohistochemically, all were CD34 and showed nuclear positivity for PRDM10; focal positivity for cytokeratins was seen in 5/6 cases. PRDM10 immunoreactivity was evaluated in 50 soft tissue tumors that could mimic PRDM10-rearranged tumors, including 4 cases exhibiting histologic features within the spectrum of SCD34FT. Except for 2/6 pleomorphic liposarcomas and 1/4 myxofibrosarcomas, other tumors did not show nuclear positivity but displayed weak to moderate cytoplasmic immunoreactivity. In conclusion, PRDM10-rearranged soft tissue tumor is characterized by pleomorphic morphology and a low mitotic count. Its morphologic spectrum overlaps with SCD34FT. Clinical features of this small series suggest an indolent behavior, justifying its distinction from UPS and other sarcomas. |
