Objective: To investigate the clinicopathological features, immunophenotypes and molecular genetics of EWSR1-SMAD3 positive fibroblastic tumor (ESFT) with an emphasis on differential diagnosis. Methods: The clinicopathological data, immunohistochemical profiles and molecular profiles of 3 ESFT cases diagnosed at the Department of Pathology, Fudan University Shanghai Cancer Center from 2018 to 2021were analyzed. The related literature was also reviewed. Results: There were two males and one female. The patients were 24, 12 and 36 years old, respectively. All three tumors occurred in the subcutis of the foot with the disease duration of 6 months to 2 years. The tumors were presented with a slowly growing mass or nodule, accompanied with pain in 1 patient. The tumors ranged in size from 0.1 to 1.6 cm (mean, 1.0 cm). Microscopically, the tumors were located in the subcutaneous tissue with a nodular or plexiform growth pattern. They were composed of cellular fascicles of bland spindle cells with elongated nuclei and fine chromatin. One of the tumors infiltrated into adjacent adipose tissue. There was no nuclear atypia or mitotic activities. All three tumors showed prominent stromal hyalinization with zonal pattern present in one case. Focal punctate calcification was noted in two cases. The immunohistochemical studies showed that tumor cells were diffusely positive for ERG and negative for CD31 and CD34, with Ki-67 index less than 2%. Fluorescence in situ hybridization on the two tested cases identified EWSR1 gene rearrangement. The next generation sequencing analysis demonstrated EWSR1-SMAD3 fusion in all three cases. During the follow up, one patient developed local recurrence 24 months after the surgery. Conclusions: ESFT is a benign fibroblastic neoplasm and has a predilection for the foot, characterized by ERG immunoreactivity and EWSR1-SMAD3 fusion. Local recurrence might occur when incompletely excised. Familiarity with its clinicopathological features is helpful in distinguishing it from other spindle cell neoplasms that tend to occur at acral sites.
Adult ; Child ; Female ; Humans ; Male ; Biomarkers, Tumor/analysis* ; China ; In Situ Hybridization, Fluorescence ; Neoplasms, Fibrous Tissue/pathology* ; RNA-Binding Protein EWS/genetics* ; Smad3 Protein/genetics* ; Soft Tissue Neoplasms/surgery*

OBJECTIVETo study the clinicopathologic characteristics and diagnostic criteria of interdigitating dendritic cell sarcoma/tumor (IDCS/T).

METHODSThe clinical features, histologic findings and results of immunohistochemical study in six cases of IDCS/T were analyzed, with review of literature.

RESULTSThe age of patients ranged from 20 to 68 years. The sites of involvement included lymph node, tonsil and soft tissue. Histologically, the tumor cells were arranged in sheets, fascicles or whorls and intimately admixed with abundant lymphocytes and plasma cells. They were oval to spindly in shape and contained pale eosinophilic cytoplasm, oval nuclei and distinct nucleoli.Immunohistochemical study showed that the tumor cells were positive for S-100 protein and CD68.

CONCLUSIONSIDCS/T is a rare malignant tumor with poor prognosis. It carries distinctive histologic pattern and immunophenotype. The entity needs to be distinguished from follicular dendritic cell sarcoma/tumor, anaplastic large cell lymphoma and other spindle cell sarcomas in occurring soft tissue.

Adult ; Aged ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Dendritic Cell Sarcoma, Follicular ; metabolism ; pathology ; Dendritic Cell Sarcoma, Interdigitating ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Histiocytoma, Malignant Fibrous ; metabolism ; pathology ; Histiocytosis, Langerhans-Cell ; metabolism ; pathology ; Humans ; Lymph Nodes ; pathology ; Lymphoma, Large-Cell, Anaplastic ; metabolism ; pathology ; Male ; Middle Aged ; Neck ; S100 Proteins ; metabolism ; Sarcoma ; pathology ; Soft Tissue Neoplasms ; metabolism ; pathology ; Thigh ; Tonsillar Neoplasms ; metabolism ; pathology ; Vimentin ; metabolism ; Young Adult

OBJECTIVETo study the clinicopathologic features, immunophenotype, molecular genetics and differential diagnosis of solid variant of angiomatoid fibrous histocytoma.

METHODSThe clinicopathologic features of 3 cases of solid variant of angiomatoid fibrous histocytoma were analyzed and the literature was reviewed.

RESULTSThere were a total of 2 males and 1 female. The age of patients ranged from 9 to 12 years. The patients presented with a painless mass located in left forearm, left knee or back. The lesions were treated by complete surgical resection. On gross examination, the tumors varied from 1.6 cm to 4.5 cm in greatest dimension. They were well-circumscribed and had pale yellow to grayish-red solid cut surface. Histologically, the tumor was composed of histocytoid cells arranged in sheet-like pattern. A fibrous pseudocapsule surrounded by lymphocytes and plasma cells was identified. Immunohistochemical study showed that the tumor cells in all cases were positive for vimentin and CD68. They were negative for S100 protein, cytokeratin, CD34, CD31, smooth muscle actin, CD35, CD21 and CD30. Two cases also expressed CD99 and one of them was positive for desmin and epithelial membrane antigen. Fluorescence in-situ hybridization was positive for EWSR1 gene.

CONCLUSIONSSolid type represents a variant of angiomatoid fibrous histocytoma and is considered as tumor of borderline malignant potential. Definitive diagnosis requires thorough histologic examination and clinical correlation. Immunohistochemistry and EWSR1 gene study are helpful in further delineation and differential diagnosis. Complete resection or wide local excision with post-operative follow up is the main modality of treatment.

Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Back ; Calmodulin-Binding Proteins ; genetics ; Child ; Dendritic Cell Sarcoma, Follicular ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Forearm ; Histiocytoma, Malignant Fibrous ; genetics ; metabolism ; pathology ; surgery ; Humans ; Knee ; Male ; Neoplasms, Muscle Tissue ; pathology ; Neurilemmoma ; metabolism ; pathology ; RNA-Binding Protein EWS ; RNA-Binding Proteins ; genetics ; Soft Tissue Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Vimentin ; metabolism

OBJECTIVETo study the clinicopathologic features and histogenesis of calcifying fibrous tumor (CFT).

METHODSThe clinical manifestations, histopathologic characteristics and immunophenotype were analyzed in 11 cases of CFT.

RESULTSThe male-to-female ratio was 5:6, with a mean age of 38 years and age range of 25 to 52 years. The sites of involvement included abdominopelvic cavity (n=6), soft tissue (n=4) and scrotum (n=1). Most patients presented with a gradually enlarging and painless mass. Nearly half of the cases were associated with other diseases or history of inflammation, trauma or surgical intervention. One third of the tumors represented incidental findings and showed no recurrence after resection. Imaging revealed a solitary solid soft tissue mass or multiple nodules with clear borders and associated high-density calcifications. Macroscopically, the tumors were well-circumscribed but non-encapsulated. They ranged from 0.5 to 20.0 cm in diameter and were tan-greyish, round to oval, lobulated or irregular and solid with rubbery consistency. The cut surface was whitish to tan-yellowish, gritty and showed scattered spotty yellowish discoloration corresponding to the foci of dystrophic calcifications. Histologically, CFT was composed of hyalinized fibrous tissue and thickened vessel walls with interspersed bland spindly fibroblastic cells, scattered psammomatous calcifications, dystrophic calcification and lymphoplasmacytic infiltration. In addition, focal cloak-like polymorph infiltration at the tumor periphery and entrapment of adipocytes and nerves were demonstrated in some cases. Foci resembling solitary fibrous tumor, fibromatosis, keloid or inflammatory myofibroblastic tumor were observed. Immunohistochemical study showed that the tumor cells were diffusely positive for vimentin and focally positive for CD34, factor VIII-related antigen and beta-catenin. The admixed plasma cells were notably IgG positive, with more than 50% being IgG4 positive.

CONCLUSIONSCFT has characteristic histopathologic manifestations and shows morphologic and immunohistochemical overlaps with known IgG4-related sclerosing diseases. It is possible that CFT may represent another example of IgG4-related diseases. It often runs a benign clinical course, with rare recurrence after surgical resection. Previous inflammation and trauma may be the precipitating factors of CFT.

Abdominal Neoplasms ; metabolism ; pathology ; surgery ; Adult ; Antigens, CD34 ; metabolism ; Calcinosis ; metabolism ; pathology ; surgery ; Female ; Follow-Up Studies ; Genital Neoplasms, Male ; metabolism ; pathology ; surgery ; Humans ; Immunoglobulin G ; metabolism ; Incidental Findings ; Male ; Middle Aged ; Neoplasms, Fibrous Tissue ; metabolism ; pathology ; surgery ; Pelvic Neoplasms ; metabolism ; pathology ; surgery ; Retrospective Studies ; Scrotum ; pathology ; Soft Tissue Neoplasms ; metabolism ; pathology ; surgery ; Vimentin ; metabolism ; beta Catenin ; metabolism ; von Willebrand Factor ; metabolism

Adolescent ; Adult ; Breast Neoplasms ; pathology ; Carcinoma ; pathology ; Diagnosis, Differential ; Endothelium, Vascular ; pathology ; Fasciitis ; pathology ; Female ; Hemangiosarcoma ; pathology ; Histiocytoma, Malignant Fibrous ; pathology ; Humans ; Hyperplasia ; pathology ; Leiomyoma ; pathology ; Leiomyosarcoma ; pathology ; Middle Aged ; Soft Tissue Neoplasms ; pathology ; Uterine Neoplasms ; pathology ; Vascular Diseases ; pathology

OBJECTIVETo study the clinicopathologic features, immunophenotype and differential diagnosis of angiomatoid fibrous histiocytoma (AFH).

METHODSThe clinicopathologic features of 5 cases of AFH were analyzed. Immunohistochemical study was carried out and the literature was reviewed.

RESULTSThere were a total of 3 males and 2 females. The average age of patients was 21.4 years old. The average duration of symptoms was 13 months. The patients primarily presented with a slowly enlarging painless deep dermal or subcutaneous mass. The mass was located in the head and neck region in 3 cases, elbow in 1 case and foot in 1 case. The patients underwent complete resection of the tumor, with no adjuvant chemotherapy and/or radiotherapy given. During a period of follow up for 10 to 29 months, all of them had no recurrence or distant metastasis. Gross examination showed that the tumor was well-circumscribed and had a grey-colored cut surface, with focal hemorrhagic cystic changes. The average tumor dimension was 1.9 cm. Histologically, the tumor was composed of histiocytoid or spindly cells arranged in nodular pattern. Fibrillary neuropil-type intercellular material was identified in all cases and a fibrous pseudocapsule surrounded by lymphocytes and plasma cells was demonstrated in 3 cases. Immunohistochemical study showed that all of them were positive for vimentin and negative for S-100 protein, pan-cytokeratin, CD34 and CD31. Three of the cases expressed desmin and CD68. Two cases were epithelial membrane antigen and CD99-positive.

CONCLUSIONSAFH is a rare tumor of intermediate malignant potential. Definitive diagnosis requires thorough histologic examination and clinical correlation. Immunohistochemistry is also helpful for diagnosis and differential diagnosis. Wide local excision with post-operative follow up is the main modality of treatment.

Adolescent ; Adult ; Aneurysm ; metabolism ; pathology ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Chemotherapy, Adjuvant ; Child ; Desmin ; metabolism ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Histiocytoma, Benign Fibrous ; metabolism ; pathology ; surgery ; Histiocytoma, Malignant Fibrous ; pathology ; Humans ; Male ; Radiotherapy, Adjuvant ; Soft Tissue Neoplasms ; metabolism ; pathology ; surgery ; Vimentin ; metabolism ; Young Adult

Aged, 80 and over ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Diagnosis, Differential ; Fasciitis ; pathology ; Fibroblasts ; pathology ; Fibrosarcoma ; metabolism ; pathology ; surgery ; Forearm ; Histiocytoma, Malignant Fibrous ; pathology ; Humans ; Male ; Myxosarcoma ; metabolism ; pathology ; surgery ; Soft Tissue Neoplasms ; metabolism ; pathology ; surgery ; Vimentin ; metabolism ; alpha 1-Antichymotrypsin ; metabolism

Diagnosis, Differential ; Hemangiopericytoma ; metabolism ; pathology ; Hemangiosarcoma ; metabolism ; pathology ; Histiocytoma, Malignant Fibrous ; metabolism ; pathology ; Humans ; Immunohistochemistry ; Leiomyosarcoma ; metabolism ; pathology ; Nerve Sheath Neoplasms ; metabolism ; pathology ; Neuroectodermal Tumors, Primitive ; metabolism ; pathology ; Rhabdoid Tumor ; metabolism ; pathology ; Rhabdomyosarcoma ; metabolism ; pathology ; Soft Tissue Neoplasms ; metabolism ; pathology ; Urinary Bladder ; metabolism ; pathology

OBJECTIVETo study the pathological characteristics, diagnosis and differential diagnoses of hemangiopericytoma-solitary fibrous tumor with giant cells.

METHODSPathological characteristics of seven cases of orbital and extraorbital hemangiopericytoma-solitary fibrous tumors with giant cells were evaluated by HE and immunohistochemistry (EnVision method).

RESULTSTwo cases were located in the orbit, one of which had recurred. Five cases were located in the extraorbital regions. Histologically, the tumors were well-circumscribed and composed of non-atypical, round to spindle cells with collagen deposition in the stroma. The tumors had prominent vasculatures and in areas, pseudovascular spaces lined by multinucleated giant cells lining which were also present in the stroma. Immunohistochemically, both neoplastic cells and multinucleate giant cells expressed CD34. Seven patients underwent tumor excision and were well and without tumor recurrence upon the clinical follow-up.

CONCLUSIONSHemangiopericytoma-solitary fibrous tumor with giant cells is an intermediate soft tissue tumor. It typically involves the orbital or extraorbital regions. Histologically, the tumor should be distinguished from giant cell fibroblastoma, pleomorphic hyalinzing angiectatic tumor of soft part and angiomatoid fibrous histiocytoma.

12E7 Antigen ; Adult ; Antigens, CD ; metabolism ; Antigens, CD34 ; metabolism ; Cell Adhesion Molecules ; metabolism ; Dermatofibrosarcoma ; pathology ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Hemangiopericytoma ; metabolism ; pathology ; surgery ; Histiocytoma, Benign Fibrous ; pathology ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Orbital Neoplasms ; metabolism ; pathology ; surgery ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Soft Tissue Neoplasms ; pathology ; Solitary Fibrous Tumor, Pleural ; metabolism ; pathology ; surgery ; Solitary Fibrous Tumors ; metabolism ; pathology ; surgery ; Young Adult

We describe 2 cases of malignant fibrous histiocytomas (MFHs) that spontaneously developed in young pet dogs. To classify these tumors, we applied a panel of antibodies (vimentin, desmin, alpha-SMA, and ED1) and Azan staining for collagen. The MFHs were most consistent with osteoclast-like giant and inflammatory cell types. The first case had positive staining for ED1 and vimentin, and given the osteoclast-like giant cells, calcification sites accompanying peripheral giant cell infiltrates. The latter case, the inflammatory cell type, exhibited a storiform-pleomorphic variant of neoplastic cells, including an ossifying matrix. MFHs are among the most highly aggressive tumors occurring in soft tissue sarcomas in elderly dogs; however, MFHs have been poorly studied from a diagnostic point of view. Herein, we describe the histologic and immunohistologic features of MFHs in detail, thus classifying the subtypes of these tumors.
Animals ; Biopsy/veterinary ; Dog Diseases/diagnosis/*pathology ; Dogs ; Female ; Histiocytoma, Malignant Fibrous/diagnosis/pathology/*veterinary ; Immunohistochemistry/veterinary ; Male ; Soft Tissue Neoplasms/diagnosis/pathology/*veterinary