The Role of Radiotherapy in the Management of Choroid Plexus Neoplasms

Choroid plexus papillomas are very rarely reported neoplasms in both the surgical and radiological literature. The authors present their series of 7 papillomas and 1 carcinoma. They review the recent and former literature with the aim of demonstrating the role and usefulness of radiotherapy.

Comparative histopathological study of pulmonary tuberculosis in human immunodeficiency virus-infected and non-infected patients

SETTING

Clinical features of human immunodeficiency virus (HIV)-associated tuberculosis depend upon the patients' residual immunity. An immune-dependent presentation has also been described at the histopathological level in many extra-pulmonary sites, but no descriptions have so far been made on the histopathology of HIV-associated pulmonary tuberculosis.

OBJECTIVE

To compare the histopathological features of pulmonary tuberculosis in HIV-infected subjects and seronegative patients.

DESIGN

We carried out a retrospective comparative study on 16 HIV-infected subjects and 16 seronegative patients with culture-proven pulmonary tuberculosis who underwent transbronchial biopsy. We evaluated the bacillary burden and the parenchymal inflammatory reaction by means of a four-graded scoring system giving an approximate quantitative measure of the two parameters.

RESULTS

HIV-associated pulmonary tuberculosis was found to differ significantly from disease forms seen in seronegative patients, with a significant tendency to develop highly bacillary and poorly reactive histopathological pictures along with the downgrading evolution of immune function.

CONCLUSION

Pathologic features of pulmonary tuberculosis in HIV-infected subjects differ from those encountered in seronegative patients depending upon the individual immunity of the former. HIV-associated progressive depletion of CD4+ lymphocytes leads to substantial changes in pulmonary reactivity to Mycobacterium tuberculosis; multibacillary pictures in a background of loose inflammatory reactions are quite common findings at the extreme phase of HIV-related immune deterioration.

Interstitial lung granulomas as a possible consequence of exposure to zirconium dust

A case of interstitial lung granulomas is described in a worker exposed to zirconium compounds. Chest X-rays revealed diffuse slight reticular interstitial radio-opacities (ILO classification, 1/0 s/t). Histological examination of transbronchial biopsy tissue revealed small interstitial nonconfluent granulomas with epithelioid and giant cells showing no central necrosis, with PAS-positive diastase-resistant small weakly birefringent particles in interstitial histiocytes. These histological and stain findings, which are characteristic of zirconium skin lesions and granulomas, suggest zirconium interstitial lung disease.

Thymic cyst appearing after treatment of mediastinal non-Hodgkin lymphoma

We report the first case of a thymic cyst appearing in the course of treatment for non-Hodgkin lymphoma of the anterior mediastinum. The patient was a 9-year-old child in whom an abnormal contour of the left cardiac border persisted after chemotherapy, suggesting residual disease. The mass was found at thoracotomy to be a benign thymic cyst. The lesion was not present 2 years previously, and most likely represented cystic degeneration of the thymus, secondary to lymphomatous involvement. CT scan was not helpful in distinguishing the cystic lesion from residual lymphoma.

Atypical lung carcinoid with GFAP immunoreactive cells

A case of atypical carcinoid with peculiar histological and ultrastructural pattern and immunohistochemical phenotype is presented. The neoplasm is composed of three types of cells. Type 1 cells are small to medium sized, fusiform, with scarce cytoplasm and are arranged in fascicles. Type 2 cells are cuboidal and line acinar structures. Type 3 cells have more abundant eosinophilic cytoplasm, larger nuclei and are arranged in fascicles intersecting with fascicles of type 1 cells, and sometimes surround acinar structures. The three cell types are present both in the primary lesion and in its lymph node metastases. Immunohistochemistry demonstrates immunoreactivity of all cell types for general neuroendocrine markers. Cytokeratin immunoreactivity is more prominent in type 1 and 2 cells, and is only focally expressed in type 3 cells. Type 3 cells are also immunoreactive for glial fibrillary acidic protein (GFAP), alpha-actin, S-100 protein, vimentin. Electron microscopic examination confirms the neuroendocrine nature of the cells, and show that type 3 cells have prominent bundles of intermediate filaments, electron-dense granules and junctional complexes. To our knowledge, this is the first case of atypical lung carcinoid with GFAP immunoreactivity. The nature of type 3 GFAP positive cells is unclear. There are some clues pointing to their sustentacular nature, and other ones pointing to a myoepithelial origin, but the data are inconclusive. Type 3 cells may be the malignant counterpart of sustentacular cells seen in typical carcinoids, but their GFAP positivity and the presence of electron-dense granules are very unique features, which differentiates them from sustentacular cells. Alternatively, their unusual GFAP + immunohistochemical phenotype may be due to aberrant expression of cytoskeletal proteins.

Development of innumerable neuroendocrine tumorlets in pulmonary lobe scarred by intralobar sequestration. Immunohistochemical and ultrastructural study of an unusual case

We describe the microscopic, histochemical, immunohistochemical, and ultrastructural features of hundreds of neuroendocrine tumorlets occurring within a pulmonary lobe severely scarred by intralobar sequestration in a nonsmoking 49-year-old white man. To our knowledge, there have thus far been no descriptions or detailed analyses of neuroendocrine tumorlets arising within a pulmonary sequestration. The neuroendocrine tumorlets appeared in the form of minute aggregates--mostly microscopic, up to a maximum of 0.3 cm in greatest diameter--of small round and short spindle-shaped cells. They were organized in compact nests of fascicles and were supplied with round or elongated euchromatic nuclei and scant weakly eosinophilic cytoplasm. The neuroendocrine tumorlets were clustered around diseased bronchioles or embedded in a fibrotic pulmonary parenchyma with a distinctive infiltrative appearance. Sometimes they lay near an artery channel without an identifiable bronchiole or herniated into distal airways. Most of the neuroendocrine tumorlets were strongly argyrophilic on Grimelius staining. Immunohistochemically, there was reactivity for markers of epithelial and neuroendocrine differentiation together with evidence of orthotopic production of calcitonin, serotonin, and gastrin-releasing peptide and ectopic production of vasoactive intestinal peptide. Ultrastructurally, most of the neuroendocrine cells showed 100- to 120-nm dense-core membrane-bound secretory granules; mucus secretory cells were also present. We prefer the term neuroendocrine tumorlets over the generally used term carcinoid tumorlets, because the nature of these lesions is undefined and the relationship with neuroendocrine pulmonary neoplasms is not yet established.

Benign multicystic mesothelial proliferation of the peritoneum: immunohistochemical and electron microscopical study of a case and review of the literature

We report a case of benign multicystic mesothelial proliferation (the so-called multicystic peritoneal mesothelioma) arising multifocally in the abdomen of a 46-year-old white man. His anamnesis showed an 8-year history of intermittent pain in the right lower abdominal quadrant. Mucin stains, immunohistochemistry, and electron microscopy confirmed the mesothelial origin of the lesion. Review of the available literature allowed us to find another 85 reported cases of benign multicystic mesothelial proliferations of the peritoneum. Out of these cases, eighteen only occurred in men, the majority being reported in middle-aged women mostly with complaints of abdominal pain. Electron microscopy or immunohistochemistry are needed to make a differential diagnosis towards other multicystic lesions, such as peritoneal cystic lymphangioma. Although multicystic mesothelial proliferations of the peritoneum have often been regarded as benign neoplasms, the true nature--neoplastic or hyperplastic--of these lesions still remains greatly elusive. Therefore, we believe that the unbinding term benign multicystic mesothelial proliferation (first used with regard to the unique hitherto reported case arisen in the pleural cavity) should be considered at present more appropriate to indicate even these peritoneal lesions.

Ultrastructural morphology of folliculo-stellate cells in human pituitary adenomas

Fifty-six pituitary adenomas were studied by electron microscopy in a search for the presence of folliculo-stellate cells (FSCs) with the aim of evaluating their prevalence and ultrastructural morphology. FSCs were scattered in two adenomas (one oncocytoma and one densely granulated GH cell adenoma) and were numerous in a sparsely granulated GH cell adenoma; their overall prevalence was 5.4%. Ultrastructural examination of the three neoplasms revealed that FSCs were hypertrophic element with abundant cytoplasm and organelles (in contrast to FSCs of the normal pituitary) and no obvious signs of neoplastic transformation. Junctional complexes between FSCs were similar to those described in the normal gland. Numerous follicular structures were lined by FSCs. FSCs in pituitary adenomas are probably nonneoplastic, reactive cells showing signs of hyperactivity, similar to FSCs found during pituitary hypersecretion and in estrogen-induced tumor.

Glial fibrillary acidic protein immunoreactivity in human respiratory tract cartilages and pulmonary chondromatous hamartomas

Immunocytochemical investigation was performed on a large series of adult, neonatal, and fetal respiratory tract cartilages to ascertain their immunoreactivity for glial fibrillary acidic protein (GFAP) and vimentin. Two polyclonal and six different monoclonal antibodies were used to document the presence of GFAP-immunoreactive chondrocytes in all the fetal and neonatal cartilages as well as in the adult epiglottis, arythenoids, and lobar, segmental, and subsegmental bronchi. The number of chondrocytes showing GFAP immunoreactivity decreased from fetal life to adulthood. Simultaneous immunoreactivity for GFAP and vimentin has also been ascertained in chondrocytes and in perichondrial stellate or elongated cells of the 25 chondromatous hamartomas investigated. These findings document yet another "inappropriate" pattern of intermediate filament immunoreactivity in normal and neoplastic human cells, and contradict the widely held supposition that the expression of GFAP is restricted to cells of glial origin.

Infantile digital fibromatosis-like tumour (inclusion body fibromatosis) of adulthood: report of two cases with ultrastructural and immunocytochemical findings

Two adult cases of a cutaneous lesion indistinguishable from typical infantile digital fibromatosis are added to the unique similar case so far reported in adulthood. The immunocytochemical localization of vimentin and muscle actin in the proliferating cells confirms their myofibroblastic nature and establishes closer relationships between the adult and the infantile variants of this entity. These two variants, however, appear to be clinically different, since all the adult cases were extradigital and did not recur after surgical excision. The term inclusion body fibromatosis underlines the histological hallmark of the lesion and should be used to identify this entity in place of recurrent infantile digital fibromatosis which does not seem any longer appropriate.

Ependymoma of the mediastinum

A case of primary ependymoma of the mediastinum is reported. The tumor was adherent to the lung and metastasized to adjacent mediastinal lymph nodes. An autopsy showed no evidence of tumor in the central nervous system. The diagnosis of ependymoma was confirmed by the immunohistochemical positivity for glialfibrillary acidic protein. To the best of our knowledge, this is the first reported example of an ependymoma in this location.

Secondary amyloidosis and cystic fibrosis. A morphological and histochemical study of five cases

The pathological findings of five cases of amyloidosis associated with Cystic Fibrosis are reported. Rectal biopsy led to the diagnosis of amyloidosis in four patients. In three cases the diagnosis was confirmed at autopsy, with involvement of spleen, liver, kidneys, adrenal glands, thyroid and other organs. It seems that Secondary Amyloidosis provokes a significant, although rare, complication of Cystic Fibrosis as greater numbers of these patients survive into adulthood.

Choroid plexus tumors. An immunocytochemical study with particular reference to the coexpression of intermediate filament proteins

Sixteen choroid plexus tumors (CPTs) have been investigated for the localization of different immunocytochemical markers of epithelial and nonepithelial nature, namely, simple epithelial-type cytokeratins, vimentin, glial fibrillary acidic protein (GFAP), a panepithelial antigen defined by the lu-5 monoclonal antibody (lu-5 antigen), S-100 protein, and epithelial membrane antigen (EMA). Intermediate filament proteins have been identified in paraffin sections of 14 of 16 cases (87.5%). In all these tumors, cytokeratins and vimentin were constantly coexpressed by the neoplastic cells, in a manner similar to that of the cells lining normal choroid plexus. In 7 of these 14 cases, in addition to cytokeratins and vimentin, the neoplastic cells were shown to coexpress GFAP, which is not synthesized by their normal cell counterpart. The appearance of GFAP immunoreactivity in CPTs might be related to an ependymal differentiation of the neoplastic cells, because normal ependyma and ependymomas constantly coexpress GFAP and vimentin. The simultaneous expression of three distinct intermediate filament proteins by the same neoplastic cells is an exceedingly rare phenomenon, which has never been reported by double labeling technique in neoplasms of the central nervous system. Despite the complex antigenic profile of the CPT, which includes immunoreactivity for lu-5 antigen, S-100 protein, and EMA in most of the cases, positivity for three different epithelial markers indicates that these tumors have an epithelial nature. Moreover, the immunocytochemical typing of CPT with the panel of antibodies used in the current investigation allows differentiation from other primary and metastatic central nervous system tumors.

Salazopyrin-induced eosinophilic pneumonia

A patient with ulcerative colitis developed eosinophilic pneumonia following treatment with Salazopyrin. The pneumonia resolved following discontinuation of the drug and the start of treatment with prednisolone. When the treatment with prednisolone was stopped the patient developed eosinophilic pneumonia again. When the treatment with prednisolone was resumed all side effects disappeared definitively.

[Renal leiomyoma (presentation of a clinical case)]

The authors report a case of symptomatic renal leiomyoma. Such neoplasm is very rare and, as to the symptomatic form, only some tens of cases are recorded.

Metachronous coexistence of laryngeal pseudolymphoma and squamous cell carcinoma. An unreported case

An unreported case of metachronous coexistence of laryngeal pseudolymphoma and squamous cell carcinoma is described. The long follow-up of the patient (above 11 years), without any evidence of lymphoreticular disease elsewhere, was in favor of a diagnosis of lymphoid hyperplasia of the larynx. The occurrence in the same organ of a squamous cell carcinoma has allowed the thorough investigation of the reactive lesion. The additional cases of laryngeal pseudolymphoma reported in the English literature are reviewed.