Angiomatoid malignant fibrous histiocytoma

Summary A case of an angiomatoid malignant fibrous histiocytoma is presented. The electron microscopic findings demonstrate the presence of a variety of tumor cell types including smooth and striated muscle cells. This indicates that malignant fibrous histiocytoma originates from a pluripotent primitive mesenchymal cell.     

An ultrastructural study of malignant fibrous histiocytoma of the larynx

Malignant fibrous histiocytoma (MFH) of the vocal cord occurring in a 46-year-old male was studied immunohistochemically and ultrastructurally. The tumor consisted of the two main areas, pleomorphic and storiform. Immunohistochemical staining was strongly positive for α1-antitrypsin and α1-antichymotrypsin, and negative for desmin, keratin, myoglobin, actin, carcinoembryonic antigen, and S100 protein. Ultrastructurally, this MFH consisted of four different types of cells which were either fibroblast-like, histiocyte-like, myofibroblast-like, or with features of both the fibroblast and histiocyte types. Transition forms between the four types of cells were also found. This suggests that cells of MFH are derived from the same undifferentiated stem cells.     

An immunohistochemical study of differentiation in malignant fibrous histiocytoma

Immunohistochemistry was used to examine 10 cases of malignant fibrous histiocytoma. Malignant cells in all cases expressed vimentin and in eight there was co-expression of either desmin or neurofilament, both of these being present in four cases. In addition, cytokeratin was found in one case. In each tumour, a population of small cells was identified which had the staining characteristics of benign macrophages, and this was distinct from the tumour cells. This study supports the concept that malignant fibrous histiocytoma is a tumour of mesenchymal cells rather than of histiocytes and emphasizes the diversity of its cytostructure.     

Malignant fibrous histiocytoma

Summary The ultrastructural findings in 17 cases of malignant fibrous histiocytoma (MFH) are described. The tumors consisted of fibroblast-like cells and histiocyte-like cells in different proportions in different cases. Intermediate, undifferentiated, xanthomatous and multinucleated giant cells were also identified. In 12 of 17 cases myofibroblasts were evident. Acid phosphatase activity was detected cytochemically in the Golgi zone, endoplasmic reticulum and lysosomes (GERL) mainly within histiocyte-like cells, in three cases. These observations indicate that the GERL of the tumor cells are engaged in the formation of lysosomes. The polymorphic cellular composition, including undifferentiated cells, lends support to the concept that the MFH originates from a primitive multipotent undifferentiated mesenchymal cell.Supported by Grants-in-aid for Cancer Research from the Ministry of Health and Welfare (52-1), and from the Ministry of Education, Science and Culture (401057) of Japan and by a Grant from the Fukuoka-ken Anti-Cancer Association. 1976Presented at the 69th Annual Meeting of the Japanese Pathological Society on June 26, 1980, Sapporo     

Omental malignant fibrous histiocytoma with a unique rough endoplasmic reticulum inclusion

The laminated inclusions in the rough endoplasmic reticulum (RER) are peculiar structures seen only in some cases of chondrocytes of pseudoachondroplasia. These ultrastructurally unique organelles have not yet been reported in inflammatory malignant fibrous histiocytoma (MFH). We describe an omental mass showing unique laminated inclusions in the RER in a young man with intra-abdominal inflammatory MFH. The most striking ultrastructural feature was a dilated RER containing a fine granular substance and a more electron-dense material exhibiting an onion skin-like lamellated or maze-like pattern, mimicking that of so-called laminated inclusions. These lamellated inclusions occupied most of the cytoplasm of the tumor cells. We speculate that the ultrastructural finding of the laminated RER inclusion is not specific for cartilage cells, but may represent abnormal accumulation of some kind of glycoprotein material or matrix protein. This granular material may undergo organization to form a peculiar laminated structure, probably due to a metabolic or fixation process. Further study is needed to elucidate the nature of this material.     

Malignant fibrous histiocytoma of the esophagus

A 78-year-old man presented with an esophageal polyp that was confirmed by Immunohistochemistry and electron microscopy to be malignant fibrous histiocytoma. The tumor was comprised of a proliferation of spindle-shaped cells admixed with bizarre giant cells. These tumor cells were immunoreactive for smooth muscle actin, vimentin, α-1-arrti-chymotrypsin and CD68. Electron microscopic examination revealed the myoflbroblastic and histtocytic features of the tumor cells. No elements of epithelial or myogenic differentiation were found in the tumor. Malignant fibrous histiocytoma of the esophagus is extremely rare, with 10 cases being documented so far in the literature. The differential diagnosis of pteomorphic tumors of the esophagus is discussed.     

Inflammatory malignant fibrous histiocytoma of kidney: a case report

Among the renal sarcomas, inflammatory malignant fibrous histiocytoma (MFH) is an extremely rare presentation. A 45-year-old woman presented with acute retention urine following an episode of gross hematuria. Computerized tomography showed a solid mass at the lower pole of the left kidney. The patient underwent left nephrectomy. Histologically and immunohistochemically, the tumor was diagnosed as an inflammatory subtype of MFH. Histological appearances of inflammatory MFH vary widely and frequently overlap with benign reactive conditions such as Xanthogranulomatous pyelonephritis (XGPN) and malignant lesions, e.g. malignant lymphoma and, less frequently, a sarcomatoid variant of renal cell carcinoma. It is important, though difficult, to differentiate inflammatory MFH from these lesions. Careful morphological examination and immunohistochemical findings of the lesion are of great value, in particular in excluding it from its mimics. We discuss the pathological features and challenges involved in differentiating inflammatory MFH from its masquerader.     

Primary malignant fibrous histiocytoma of the spleen: an ultrastructural study

A primary malignant fibrous histiocytoma of the spleen was studied by light and electron microscopy and is believed to be the first reported. The neoplasm was predominantly fibroblastic, with a characteristic storiform pattern, and included histiocyte-like cells, giant and foam cells confirmed by ultrastructural studies. Additionally, undifferentiated cells, intermediate cells and myofibroblasts were seen. The differential diagnosis from other sarcomas and the histogenesis of this tumour are discussed.     

Inflammatory fibrous histiocytoma of the penis

A 62-year-old man presented with a penile mass which was diagnosed histologically as an inflammatory fibrous histiocytoma. The predominant inflammatory cells in the tumour were eosinophils. The tumour regressed after radiotherapy but recurred eight months later, when it showed very few inflammatory cells. At no time did this patient have an elevated white cell count. This tumour has not previously been reported on the penis, nor have eosinophils been described as the principal inflammatory cell in these tumours.     

Fine-needle aspiration cytology of angiomatoid malignant fibrous histiocytoma

Angiomatoid malignant fibrous histiocytoma (AMFH) is a rare, low-grade malignant mesenchymal neoplasm that affects mostly the extremities of children and young adults. Excisional surgery is the adequate treatment. The cytologic, immunocytologic, and histologic features noted in two patients having AMFH are presented. Cytologic smears showed histiocyte-like cells dispersed and in clusters, in close relation with eosinophilic mesenchymal fragments in a bloody background with lymphocytes. The tumor cells showed mild to moderate anisocariosis, often with nucleolus and vast, fragile cytoplasm. A fibroblastic-like spindle to ovoid cell population was also present in one patient. Immunohistochemical results are most consistent with myofibroblastic cell differentiation. When accompanied by adequate clinical information and ancillary techniques, a specific preoperative cytologic diagnosis is possible.     

Primary malignant fibrous histiocytoma of the liver—a case report with immunocytochemical observations

A case of a primary sarcomatous tumour in the liver of an elderly female is reported. The tumour consisted of bundles of spindle cells focally in a storiform pattern, intermingled with bizarre giant cells. Immunocytochemically, carcinoembryonic antigen, alpha-fetoprotein, keratin, desmin and type IV collagen could not be demonstrated. Most tumour cells, however, expressed vimentin, whereas a granular cytoplasmic immunoreactivity for alpha-1-antitrypsin and alpha-1-antichymotrypsin was shown in the giant cells. Ultrastructurally the tumour cells did not show any characteristics of epithelial derivation. The morphological and immunocytochemical data justify the conclusion that the tumour should be classified as a malignant fibrous histiocytoma.     

Malignant fibrous histiocytoma of the pancreas

An extremely rare case of malignant fibrous histiocytoma In the pancreas Is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 × 7 × 6.5cm in size. Microscopically, fibroblastic, histiocytic, and muitinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphlc pattern. Immunohtstochemically, some tumor cells were positive for lysozyme, α-1-antitrypsin, α-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient Is currently well with no evidence of recurrence or metastasis 22 months after operation.     

Primary hepatic malignant fibrous histiocytoma: Report of a case and review of the literature

Malignant fibrous histiocytoma (MFH) is a common sarcoma of adulthood, frequently arising in the extremities, but also in the abdomen and the retroperitoneum. Primary MFH of the liver, however, remains extremely rare and is one of the least diagnosed primary hepatic sarcoma. Another case of primary MFH of the liver is reported. The patient presented with a 12 cm mass involving the right and left lobes of the liver. The histopathologic examination revealed a typical MFH swirling (storiform) pattern composed of atypical spindle and giant cells. The radiologic, histologic, and clinical behavior of this rare neoplasm are reviewed.     

Clinicopathological features of angiomatoid fibrous histiocytoma: a series of 21 cases with variant morphology

We analyzed the clinicopathological features of angiomatoid fibrous histiocytoma (AFH) in 21 cases with emphasis on variant morphology. In our series, ten patients were male and eleven were female. The patients’ mean age was 26.9 years old. Tumors were located on the lower limbs in eight cases, upper limbs in three, trunk in five, head and neck in four, and trachea in one. Microscopically, thirteen cases were characterized by typical AFH. Tumor cells showed marked tumor pleomorphism with giant hyperchromatic nuclei in two cases. Mitotic figures (2-3/10HPF) were found in two cases. Focal necrosis was found in one case. A number of multinucleated giant cells were found in two cases. Two cases showed obvious myxoid change in the stromal. Prominent sclerosing changes in the stromal component were found in two cases. Immunohistochemistry staining showed tumor cells were positive for EMA, desmin, and CD68. Five cases demonstrated the presence of rearrangement of the EWSR1 gene by FISH detection. Only two patients had tumor recurrence at 3 and 6 months after tumor resection, respectively. In conclusion, AFH has variant histological patterns. The differential diagnosis includes inflammatory myofibroblastic tumor, aneurysmal fibrous histiocytoma, follicular dendritic cell tumor, and metastatic tumor of lymph node.     

Osteosarcoma with features mimicking malignant fibrous histiocytoma

Summary Three osteosarcomas (OS) with features resembling malignant fibrous histiocytoma (MFH) were selected and investigated to identify any clinico-pathological similarities. In all cases there was no significant difference from conventional OS on the radiography and laboratory data. The appearance of MFH-like features within the whole tumour tissue varied from 7% to 55%. It was composed of spindle-shaped cells arranged in short irregular fascicles and a storiform pattern admixed with osteoclast-like giant cells, but devoid of neoplastic osteoid. Such spindle-shaped cells had a poorly developed rough endoplasmic reticulum and expressed a strong alkaline phosphatase activity as well as vimentin. A series of allografts to athymic mice using the MFH-like tissues also showed histologically a proliferation of plump spindle-shaped cells with a storiform pattern lacking osteoclast-like giant cells, and intensely positive for alkaline phosphatase. These findings indicate that the MFH-like features are identified as modulated OS. The constituting cells are most likely to be poorly developed with possible phenotypic alteration in the maturation stage of osteoblastic cell lineage, but different from conventional MFH of bone as regards their distinct histochemical pattern.     

Reassessment and clinicopathological prognostic factors of malignant fibrous histiocytoma of soft parts

Recently, the category of malignant fibrous histiocytoma (MFH) has been under discussion and new entities resembling MFH have appeared. To clarify the recent situation regarding MFH, we reassessed previously diagnosed MFH cases in accordance with the most up-to-date diagnostic criteria, which included allied tumors. We carefully reassessed 428 cases that had been diagnosed in our institute during the past 28 years. Moreover, we searched for clinicopathological prognostic factors among the cases that were finally diagnosed as MFH. Among the 428 cases, 138 cases had their diagnoses changed. The revised cases included 78 leiomyosarcomas (57%; ordinary leiomyosarcoma, 45 cases; pleomorphic leiomyosarcoma, 23 cases; myxoid leiomyosarcoma, 10 cases), 12 liposarcomas (9%; pleomorphic liposarcoma, 11 cases; dedifferentiated liposarcoma, one case), seven dermatofibrosarcoma protuberans (5%), six unclassified sarcomas (4%), five primary or metastatic carcinomas (4%), four low-grade fibromyxoid sarcomas (3%), four inflammatory myofibroblastic tumors (3%), three rhabdomyosarcomas (2%), three malignant peripheral nerve sheath tumors (2%), three acral myxoinflammatory fibroblastic sarcomas (2%) and two atypical fibroxanthomas (1.5%). Among the 1974 soft tissue sarcomas registered in our institute, MFH (428 cases) had been the most common sarcoma, followed by liposarcoma, leiomyosarcoma and rhabdomyosarcoma. However, after reassessment, leiomyosarcoma proved to be the most common soft tissue sarcoma (322 cases), followed by 290 MFH, 273 liposarcomas and 202 rhabdomyosarcomas. Among these 290 cases finally diagnosed as MFH, survival data were available in 189 cases. Tumor location in the abdominal cavity, the retroperitoneum or the head and neck (P = 0.0024), tumor size of 5 cm or more (P < 0.0001), deep tumor location (P < 0.0001), high histological grade (grade 3) based on the French Federation of Cancer Centers' grading system (P = 0.0007), and high stage (stage III or IV) based on the American Joint Committee on Cancer (AJCC) staging system (P < 0.0001) were significantly worse prognostic factors by univariate analysis. In multivariate analysis, deep tumor location and high AJCC stage were independent adverse prognostic factors. We conclude that leiomyosarcoma is the most important differential diagnosis for MFH, especially pleomorphic leiomyosarcoma from storiform-pleomorphic type and myxoid leiomyosarcoma from myxoid type. Tumor depth and AJCC stage are the most important predictive prognostic factors in MFH.