Mesenchymal/radioresistant traits in granular astrocytomas: evidence from a combined clinical and molecular approach.

AIMS: Granular-cell astrocytomas (GCAs) are morphologically characterized by a prominent component of granular periodic acid-Schiff-positive cells, and show increased aggressiveness as compared with 'ordinary' astrocytomas. The aim of this study was to investigate, in a small series of three GCAs, the expression of mesenchymal/radioresistance-associated biomarkers [such as chitinase-3-like protein 1 (YKL-40), hepatocyte growth factor receptor (c-Met), and caveolin 1 (Cav1)] that could contribute to the poor outcome associated with this glioma subgroup. METHODS AND RESULTS: Our results show that GCAs, according to the new molecular glioma classifications, consistently show a prognostically negative molecular trait (IDH1wt-ATRX noloss-1p/19q nocodeletion). Furthermore, GCAs significantly differed from a control series of 33 'conventional' astrocytomas, because of diffuse and strong immunohistochemical coexpression of YKL-40, c-Met, and Cav1. CONCLUSIONS: Our findings show that specific morphological traits, such as a granular-cell component, could represent useful features in guiding the search for prognostic and predictive biomarkers that could eventually be therapy-targetable (e.g. Met inhibitors aimed at reducing radioresistance).

[Airway granular cell tumor].

The paper describes the clinical, morphological, and immunohistochemical characteristics of 13 granular cell tumors of the upper airway. These tumors are shown to have virtually the same histological and immunohistochemical features as granular cell tumors at another site. The histogenesis of these tumors is discussed. There are currently a number of more or less solid grounds for considering them as neurogenic tumors to be close to schwannomas. At the same time one cannot ignore the fact that there is morphological and immunohistochemical evidence for that the granular cell tumors have rather cytotypical than histotypical properties, which cannot implicitly assign them to nerve tissue tumors. Most likely, the granular cell tumors belong to a histogenetically heterogeneous mixed group, in this connection their place in the classification of tumors needs further investigation, by applying the criteria developed by Russian histologists and oncomorphologists.

Spindle cell oncocytomas and granular cell tumors of the pituitary are variants of pituicytoma.

Pituicytomas are neoplasms that arise from pituicytes, which are specialized glia of the posterior pituitary. Pituicytes have 5 ultrastructural variants: light, dark, granular, ependymal, and oncocytic. Granular cell tumors of the pituitary gland are thought to arise from granular pituicytes. Spindle cell oncocytomas are considered to arise from folliculostellate cells, which are sustentacular cells of the adenohypophysis. Recent data suggest that, whereas pituicytes and all 3 tumor types are positive for TTF-1, folliculostellate cells are negative for TTF-1. We investigated 7 spindle cell oncocytomas, 4 pituicytomas, and 3 granular cell tumors for their genetic (BRAF(V600E) mutation and BRAF-KIAA fusion), immunohistochemical (GFAP, vimentin, S100 protein, olig2, IDH1-R132H, NF, galectin-3, chromogranin-A, CD56, EMA, CAM5.2, CD68, TTF-1, and bcl-2), and ultrastructural features to refine their classification. All tumors had nuclear positivity for TTF-1 and were negative for CAM5.2, chromogranin-A, and NF. GFAP, vimentin, S100, galectin-3, EMA, and CD68 were variably positive in the majority of the 3 tumor groups. Olig2 was only positive in 1 pituicytoma. Whereas granular cell tumors were negative for bcl-2 and CD56, pituicytomas and spindle cell oncocytomas showed variable positivity. All tumors were negative with the IDH1-R132H mutation-specific antibody, and none had evidence of BRAF alterations (BRAF(V600E) mutation and BRAF-KIAA fusion). Diffuse TTF-1 expression in nontumorous pituicytes, pituicytomas, spindle cell oncocytomas, and granular cell tumors indicates a common pituicyte lineage. The ultrastructural variants of pituicytes are reflected in these 3 morphologic variants of tumors arising from these cells. We propose the terminology "oncocytic pituicytomas" and "granular cell pituicytomas" to refine the classification of these lesions.

Rare non-epithelial primary breast neoplasms: a ten-year experience at a Greek University Hospital.

PURPOSE: Non-epithelial breast neoplasms cover a large spectrum of histopathological entities. The demographics and clinical features are similar to epithelial breast lesions but the diagnosis, prognosis and management options are often very different. METHODS: During 2001-2010, 1362 patients were examined at the Pathology Department of the Aretaieion General Hospital for various breast lesions. All specimens were processed routinely and slides stained with hematoxylin-eosin were re-examined. The patient clinical records were examined for demographics, clinical presentation and therapeutic approach. RESULTS: In 23/1362 cases (1.68%) pathological examination showed non-epithelial lesions: in 12/1362 cases (0.8%) haemangiomas (11 women, one man), in 4 /1362 cases (0.3%) myofibroblastomas (MFB), in 2/1362 cases (0.1%) primary breast non-Hodgkin's lymphoma (NHL), in 3 /1362 cases (0.2%) granular cell tumor (GCT), and in 2/1362 cases (0.1%) angiosarcomas (one developed after radiotherapy for breast cancer). CONCLUSIONS: Non-epithelial primary breast tumors are rare (1.68%) and present significant difficulty in accurate preoperative diagnosis and in certain cases in pathological diagnosis as well, which is necessary for the selection of the appropriate treatment. Avoidance of inappropriate therapies requires a multidisciplinary management approach.

Malignant granular cell tumor: a look into the diagnostic criteria.

Fanburg-Smith et al. classified granular cell tumors (GCTs) using six criteria with high Ki-67 and p53 in malignant cases. We aim to refine their classification and reproduce their immunohistochemical findings. We, first, classified our 48 cases according to Fanburg-Smith criteria (37 benign, seven atypical, and four malignant), and performed Ki-67 and p53 on a sample of tumors. Then, we reclassified them into 44 benign and four with uncertain malignant potential (GCT-UMP) using only necrosis and/or mitoses. (1) According to Fanburg-Smith criteria: Malignant cases were significantly younger than benign and atypical ones; occurred predominantly in males; were significantly larger in size; and showed a higher Ki-67 expression but an insignificant difference in p53 staining. (2) Comparative findings: The four malignant cases according to Fanburg-Smith corresponded to our four cases with UMP. The seven atypical cases and our benign group shared similar means, except for age. None of these atypical cases recurred or metastasized. Despite its small number, our preliminary study showed similar selectivity of two more reproducible criteria (vs six) in the classification of cases of GCT with potential aggressive behavior, preserving a role for Ki-67 in difficult cases. However, metastases remain the sole definite criterion for malignancy.

Granular cell lesions in the distal female reproductive tract of aged Sprague-Dawley rats.

During the review of a rat carcinogenicity study, a spectrum of granular cell lesions was recognized in the distal female reproductive tract. To verify the diagnoses, cell populations of nine granular cell alterations of the cervix or vagina were characterized immunohistochemically and four were evaluated ultrastructurally. Immunoreactivity was demonstrated in 8/9 cases with S100 protein, 6/9 cases with neuron-specific enolase, and 7/9 cases with Leu-7. Granular cells were negative for smooth muscle-specific actin and calretinin. The immunohistochemical profile of these lesions was similar to that previously reported in other species, including humans. Ultrastructurally, as expected many lysosomal bodies were present in the cytoplasm of granular cells in all specimens evaluated. Based on the detailed evaluation of a series of lesions, we adopted the following diagnostic criteria and nomenclature for the granular cell changes of the female reproductive tract of rats. Granular cell aggregates were non-space-occupying lesions composed of clusters of typical granular cells. Benign granular cell tumors were space occupying lesions that typically contained prominent interstitial collagen and were either discrete masses or were difficult to discern from the surrounding tissues. Some benign tumors also contained foci of spindle cells with decreased granularity. Malignant tumors exhibited pleomorphism and an increased nucleus: cytoplasm ratio morphologically but had the same biologic behavior as the benign tumors. We applied these diagnostic criteria during the review of controls from 9 carcinogenicity studies. Up to 23% of control females in those carcinogenicity studies had granular cell lesions that could be classified into one of the three categories. Granular cell lesions appear to be common in the cervix/vagina of the Sprague-Dawley rat, and tumors may develop from granular cell aggregates.

Granular cell traumatic neuroma: a lesion occurring in mastectomy scars.

BACKGROUND: Granular cell changes can be observed in a variety of benign and malignant tumors, and are seen more commonly in granular cell tumors, which in about 5% of cases develop in the breast. Granular cells also have been observed in sites of previous trauma, such as surgery, and are found to be inflammatory reactions of histiocytic origin. METHODS AND RESULTS: We investigated, morphologically and immunohistochemically, 2 granular cell lesions occurring in mastectomy scars after surgery for carcinoma. Both lesions were composed of strands and nests of large granular cells, haphazardly set in a background of fibrous tissue, with sparse inflammatory infiltrates. Several tortuous hypertrophic nerve bundles were also embedded in the fibrous tissue. A few of these nerve bundles showed degenerative changes and contained granular cells. Immunohistochemically, granular cells were positive for S100 protein, neuron-specific enolase, vimentin, and CD68 antigen. CONCLUSIONS: We consider these proliferative lesions of peripheral nerves to have the features of both granular cell tumor and traumatic neuroma. These cases indicate that traumatic neuroma can undergo extensive granular cell changes and constitute a previously unrecognized entity, which we provisionally label granular cell traumatic neuroma. Granular cell traumatic neuroma has to be taken into consideration when evaluating lesions occurring at mastectomy scars and should be differentiated from malignant tumors with granular cells, such as apocrine carcinoma and alveolar soft part sarcoma.