Proliferating histiocytic lesion. (Histiocytosis-X?). Association of an extensive mediastinal and retroperitoneal sclerosing lesion with Gagel's granuloma of the posterior lobe of the pituitary

Pulmonary blastoma: an ultrastructural and immunohistochemical study with special reference to nuclear filament aggregation

A case is presented of pulmonary blastoma occurring in the right upper lobe of a 25-year-old man without distinct clinical features and laboratory abnormality. Light microscopic analysis revealed that the tumor was composed of branching glands and morulae embedded in a primitive but bland mesenchyme. Immunohistochemically the epithelial cells were immunoreactive for cytokeratins, S-100 protein, protein gene product 9.5, chromogranin A, calcitonin, and Ki-67 (MIB-1); the mesenchymal cells were immunoreactive for vimentin, actin, cytokeratins, and Ki-67; and all the tumor cells were negative for p53, estrogen receptor protein, and human chorionic gonadotropin beta. Characteristically, many epithelial cells contained optically clear nuclei which were immunoreactive for biotin (M743). Electron microscopic analysis revealed that the optically clearing change was due to replacement of the central area of the nuclei by a mass of parallel-arranged 7- to 10-nm filaments, and biotin-immunoreactive products were mainly localized in the nuclear matrix. Additionally, spherical bodies were identified in the cytoplasm of the nuclear filament-aggregated cells, suggestive of an intimate pathogenetic association of the two morphological abnormalities. The similarity of the aggregated nuclear filaments to those observed in gestational endometrium and ovarian endometrioid carcinoma implies that a similar mechanism plays a role in the pathogenesis of these abnormalities.

Intranuclear rod-shaped actin filament bundles in poorly differentiated axillary adenosquamous cell carcinoma

An axillary cystic poorly differentiated adenosquamous cell carcinoma was studied by electron microscopy and immunohistochemistry for keratin, vimentin, desmin, and actin. Many tumor cells had rod-shaped intranuclear fibrillary inclusions which consisted of 60 A microfilaments. These intranuclear inclusions reacted with antiactin antibody and were considered to be F-actin bundles. The cells having intranuclear inclusions were frequently found in areas close to the cystic space, and inclusions of tumor cells close to the cyst were thicker. However, mitotic figures were predominantly found in the periphery of the tumor. Intranuclear actin is known to be mainly soluble G-actin, and one of its important functions is reported to be the chromosome condensation in mitosis. It is speculated that the cells having intranuclear fibrillary inclusions of actin have impairment of mitosis.

Monophasic synovial sarcoma, epithelioid sarcoma and chordoid sarcoma: ultrastructural evidence for a common histogenesis, despite light microscopic diversity

Ultrastructural examination of six rare sarcomas--four monophasic spindle cell tumours, one epithelioid sarcoma, one chordoid sarcoma--has revealed marked similarities at the electron microscopic level despite widely divergent light microscopic appearances. These features consisted of: 1 the presence of two cell types, viz. a clear cell and a cell resembling the fibroblast; 2 pseudoglandular spaces with projecting microvilli or filopodia, and with related tight junctions; 3 an amorphous intercellular ground substance with focal condensation into recognizable basement membrane. The findings suggest a common maturation of these diverse tumours to synovial-like tissue, and support the proposal of Hajdu Shiu & Fortner (1977) that these be considered variants of synovial sarcoma. Published ultrastructural studies of synovial, epithelioid and chordoid sarcoma are reviewed in the light of these findings. The ultrastructural differentiation of synovial sarcoma from extraskeletal myxoid chondrosarcoma, chordoma and the spectrum of malignant spindle cell tumours is discussed.

Primary eosinophilic granuloma of the larynx

A rare case of primary eosinophilic granuloma of the larynx in a 49-year-old man is reported. The patient remains asymptomatic after a follow-up of three years. This is the third case reported in the world literature.

Primary eosinophilic granuloma of the frontal lobe

The clinical symptoms, pathological findings and surgical treatment of a case of primary frontal lobe eosinophilic granuloma are presented. Initially a frontal mass was detected that clinically seemed like a low-growth tumor. After operation, the histological, cytochemical and ultrastructural studies showed positive acid phosphatase, alpha-naftil-esterase, oil-red and PAS reactions of tumoral cells and the presence of rod-shaped bodies in proliferative histiocytes, all which confirmed the pathological diagnosis of eosinophilic granuloma. Other osseous or visceral histiocytosis-X signs were not observed. The patient remains asymptomatic after a postoperative follow-up of 2 years.

Disseminated histiocytosis X: analysis of prognostic factors based on a retrospective study of 50 cases

This work is a retrospective study of 50 cases of DHX, collected over a period of 27 years. 24 children died, 26 are still alive. The prognosis for DHX was neither dependent on age (usually occurring in children under 2 years) nor on histological findings but on the extent of the lesions. It was possible to establish a clinical staging system distinguishing 2 groups. One, where the disease was severe and almost always fatal, often included the combined symptoms of thrombocytopenia, spontaneous anemia, jaundice, hepatosplenomegaly, respiratory insufficiency and absence of osteolytic lesions. The other, with a favorable prognosis, was characterized by skin lesions, diabetes insipidus, exclusively radiological pulmonary involvement and multiple bone lesions. In cases where death did not occur, DHX was often chronic, frequently persisting for 2 years or more and leading to serious sequelae such as diabetes insipidus, growth stunting, intellectual retardation, blindness or deafness.

Intranuclear filaments in a soft tissue sarcoma

Intranuclear filaments aggregating into rodlike structures were found in cells of an undifferentiated soft tissue sarcoma in a child. Similar structures have been uncommonly described in human neoplasms, and uncertainties exist concerning the nature of the inclusion bearing cells in previous reports. The filaments were found to be resistant to mild trypsin digestion. Review of the pertinent literature indicates that these structures may represent the structural manifestation of a highly specialized functional state, rather than a degenerative phenomenon or an artifact. A certain selectivity of occurrence has also been noted. It is therefore plausible to speculate that intranuclear filaments may eventually constitute a morphologic criterion of interest for new tumor classifications.

Idiopathic fibrosis of mediastinum: a discussion of three cases and review of the literature

In two out of three cases of idiopathic fibrosis of the mediastinum there was also retroperitoneal fibrosis, and in one of them extensive fibrosis of the lungs. One of these, a fit middle-aged man, died suddenly with severe coronary artery stenosis due to fibrosis. The third case was that of a young man with a solitary fibrous mass around the right lower lobe bronchus mimicking a malignant tumour and producing bronchial stenosis. Of the various hypotheses about the aetiology and pathogenesis of the fibrous proliferation, that of an autoimmune process seemed the most likely in these cases.

Malignant fibrous histiocytoma. An electron microscopic study

Sixteen cases of malignant fibrous histiocytoma are presented. Electron microscopy of 15 cases demonstrated fibroblast-like and mononuclear and multinucleated histiocyte-like cells. A small capillary was at the center of all storiform areas examined. Ultrastructural examination can be diagnostically useful within the context of a narrow differential diagnosis by conventional microscopy and the ability, by electron microscopy, to eliminate other mesenchymal cell types. In 13 cases, follow-up information was available from 18 months to 9 years following histological diagnosis. Five patients are alive and 8 patients have died, including two non-tumor related deaths. In 3 cases follow-up was less than 4 months. The biologic behavior of the tumor in this series was generally not related to histopathological parameters. The issue of histogenesis is largely unresolvable. Ultrastructural studies of various types of fibrous histiocytomas, suggesting cells of origin other than histiocytes, give credence to the concept that the histiocyte may represent a morphologic state of a given mesenchymal cell rather than a particular cell type.

Intranuclear rodlets in an intrathyroid tumor associated with hyperparathyroidism

A tumor excised from the thyroid gland has been shown by electron microscopy to contain distinctive, intranuclear rodlets. This is the first report of such rodlets in a non-neuronal human tumor. While the parathyroid-like hormonal activity, histopathology, and clinical course are consistent with a parathyroid adenoma, the finding of the rodlets raises the question of origin from a special, neuron-related cell of the parathyroid or thyroid. The unusual cellular granularity and the abundant interstitial fibrillae also suggest an unusual cell of origin. Alternatively, a special metabolic activity may account for the rodlets, or they may have been overlooked in prior studies of adenomas.

Systemic giant-cell histiocytosis: report of a case and a review of the adult form of Letterer-Siwe disease

The multiple classifications of histiocytic disorders, and the lack of specificity in their application, have degraded the utility of such diagnostic terms as "Letterer-Siwe Disease" and "Malignant Histiocytosis". A case is presented of a systemic histiocytic proliferation with erythrophagocytosis and giant-cell formation which does not fit into any presently accepted diagnostic niche. No similar case was found in the literature. Moreover, it appears that the entity "Adult form of Letterer-Siwe disease" has been uncritically accepted on the basis of a few poorly documented cases, and should be abandoned.