No abstract

The findings support the importance of proliferative factors, tumor size and histologic patterns as possible prognostic indicators for estimating the biologic behavior of patients with GCT. Unfortunately, angiogenesis did not seem to be a useful determinant parameter of a possible aggressive behavior. However, a longer follow-up period with larger series may be required to assess the value of the parameters in prediction of patient survival.

Rosai-Dorfman Disease (RDD) is an idiopathic histiocytic proliferation affecting lymph nodes. Although extranodal involvement has been reported in diverse sites, manifestation in the central nervous system (CNS) is extremely rare, particularly in the brain parenchyma. A 39-year-old male presented with an isolated well-circumscribed brain mass in the right temporal lobe, preoperatively thought to be a meningioma. Histology and immunohistochemistry confirmed that the lesion was RDD. The intraparenchymal brain location of RDD appears to have a benign course. Although the adjuvant therapy is a treatment of choice, surgical resection seems to be the appropriate treatment modality. From the clinical point of view RDD might be an important intracerebral entity because it may mimic other lesions, particularly other histiocytic disorders.

Gliomas are tumors originating from astrocytes, oligodendrocytes or ependimal cells. Those of astrocytic origin are the most widespread of primary brain tumors and account for more then 60% of all CNS neoplasms. The current state of knowledge on the associations between tumor etiology and oxidative stress suggests that environmental factors that cause oxidative stress could also induce and promote cancer, especially in case of hereditary predisposition. Among mediators of oxidative stress, lipid peroxidation product 4-hydroxynonenal (HNE) is of particular relevance in oncology, as it is known to act as a growth-regulating factor and a signaling molecule. The aim of present study was to investigate by immunohistochemistry the presence of HNE-modified proteins in different types of astrocytoma. Our study comprised 45 astrocytic tumors. These tumors were graded in accordance with the WHO classification as diffuse astrocytomas (DA), anaplastic astrocytomas (AA) and glioblastomas (GB), while each group comprised 15 tumors. Slides of paraffin-embedded tumor tissue were stained with hematoxylin-eosin or were prepared for immunohistochemistry with monoclonal antibodies to HNE-histidine conjugate. Positive immunohistochemical reaction to HNE was analyzed semi-quantitatively. HNE positivity was proportional with malignancy of astrocytomas. The weakest presence of HNE-histidine adducts was found in DA, followed by AA and GB. Lowest intensity of HNE immunopositivity was present in tumor cells of almost all DA, predominantly around blood vessels. In malignant variants of astrocytoma, AA and GB, HNE positivity was moderate to strong, and diffusely distributed in all tumors.

This report describes a case of atypical carcinoid of the larynx with metastatic tumor to cervical lymph nodes showing features similar to paraganglioma. Immunohistochemically, both the primary and metastatic tumor were positive for epithelial membrane antigen, cytokeratin, neuron-specific enolase, chromogranin, synaptophysin, calcitonin and carcinoembryonic antigen. The sustentacular cells in pseudo-cell ball ("Zellballen") formations were shown by a positive S-100 marker. Electron microscopic analysis revealed numerous neuroendocrine granules measuring 150-250 nm in diameter. Clinical features, histological appearance, histochemical, immunohistochemical and ultrastructural findings, as well as differential diagnosis are discussed.