Myoepithelial Carcinoma of the Breast with Focal Rhabdoid Features

Myoepithelial carcinoma of the breast is extremely rare and only 33 cases have been reported in the English literature. Herein, we report a case of myoepithelial carcinoma of the breast with focal rhabdoid features. The patient was a 67‐year‐old woman, who presented with a lump of the left breast that rapidly grew to 3 cm in diameter within 3 months. Lumpectomy revealed a solid and whitish colored tumor, which was composed mainly of elongated spindle‐shaped cells with mild atypia, focal necrosis, and infiltrative margin. In a small area of the lesion, ovoid tumor cells exhibited eccentric nuclei with centrally located nucleoli and plump cytoplasm including round eosinophilic inclusions, resembling a rhabdoid tumor. Immunohistochemically, both types of tumor cells exhibited a myoepithelial phenotype. MIB‐1 index was 30%. The cytoplasmic inclusion of the ovoid cells exhibited immunopositivity for both vimentin and cytokeratin. From these findings, this tumor was diagnosed as a myoepithelial carcinoma with focal rhabdoid features. Although rhabdoid features have been reported in some types of malignant and benign tumors, this is the first report of such features in myoepithelial carcinoma of the breast.     

Rhabdoid transformation of recurrent meningioma in the cervical cord: a case report

We report a case of persistent local recurrence of rhabdoid meningioma in the cervical spinal cord. Recently, the meningioma has been reported to be undergoing rhabdoid transformation, but the clinical course is still unclear. Histopathological examination of the tumor showed that it was composed of both meningothelial cells and rhabdoid cells. At each recurrence of the tumor, the population of the rhabdoid cells had increased and the ability to grow had also increased, confirmed by the MIB-1 labeling index. This case showed that phenotypic change of the cells with rhabdoid morphology may affect meningiomas and that such changes are associated with aggressive biological and clinical behavior. This newly classified tumor should be recognized in the differential diagnosis of meningioma.     

Secretory meningioma. A distinct subtype of meningioma

Six meningiomas with abundant hyaline inclusions (pseudopsammoma bodies) were studied. As seen by light and electron microscopy, hyaline inclusions are composed of material of varying structures located in intracellular lumina lined by microvilli. A remarkable pericytic proliferation within the vessel walls was found in five cases. In all six cases, immunohistochemical examination for multiple antigens showed positive staining for carcinoembryonic antigen and epithelial membrane antigen in inclusions and surrounding cells. Weak positivity was found for keratin and secretory component in five cases and for alpha-1-antitrypsin and IgM in four cases. It is concluded that secretory meningioma is a distinct type of meningioma, usually meningothelial in type. It shows characteristic light-microscopic, ultrastructural, and immunohistochemical features of epithelial and secretory differentiation with accumulation of secretory material in the form of hyaline inclusions; marked vascular pericytic proliferation is also frequently present.     

Neuroendocrine carcinomas of the pancreas with 'Rhabdoid' features

Neuroendocrine carcinomas of the pancreas are rare neoplasms whose morphologic features generally mirror those seen in neuroendocrine tumors in other organs. Rarely, however, they may display unusual morphologic appearances that can introduce difficulties for diagnosis. We report four cases of primary neuroendocrine carcinomas of the pancreas (islet cell tumors) that were characterized by prominent "rhabdoid" features of the tumor cells. The lesions occurred in two men and two women 37-79 years of age who presented with symptoms of biliary obstruction and epigastric pain; one patient had recurrent gastric ulcers and an elevated gastrin level. The tumors were located in the head and tail of the pancreas and measured 2.5-4.5 cm in greatest diameter. Histologic examination revealed sheets of monotonous tumor cells with uniform round nuclei showing dispersed chromatin and containing abundant densely eosinophilic cytoplasmic inclusions that displaced the nuclei toward the periphery. In all cases, the rhabdoid elements appeared to merge with areas showing a more conventional neuroendocrine morphology. Immunohistochemical studies in all cases showed strong cytoplasmic positivity of the rhabdoid tumor cells for chromogranin, synaptophysin, and cytokeratin. Recognition of this unusual morphologic appearance is of importance to avoid mistaking these lesions for other types of malignant neoplasm.     

Lipomatous meningioma: report of 2 cases and review of the literature

BACKGROUND: Lipomatous meningioma is a rare but, most of the time, benign tumor. Its pathogenesis is still debated: it is usually considered to be part of the metaplastic meningioma, but several authors recently suggested that fat accumulation inside the tumor was related to metabolic disorders of the meningothelial cells. CASES DESCRIPTION: We report 2 cases of lipomatous meningioma. Both patients were women older than 60 years. One patient suffered from headache and seizures, the other one presented with behavioral disturbance. Radiological features depended on the amount of fat accumulation within the tumor. Surgical treatment allowed complete resection in both cases without any complications. Both meningiomas were of transitional-type and were apparently composed of 2 populations of cells: meningothelial cells and lipid-laden cells resembling mature adipocytes. Immunohistochemical study showed that lipid-laden cells expressed EMA, CD99, and progesteron receptor, favoring a meningothelial differentiation rather than an adipocytic lineage. CONCLUSION: Our study strongly suggests that lipomatous meningioma results from an accumulation of lipid inside meningothelial cells rather than a true metaplasia.     

Diffuse pulmonary meningotheliomatosis

Minute pulmonary meningothelial nodules are rare lesions histologically composed of small nests of epithelioid cells located within the interstitium of the lung. These nodules are generally asymptomatic and are usually found incidentally at autopsy or in surgical specimens resected for unrelated causes. The lesions are most often single, although multiple lesions with unilateral involvement of one or even all lobes of the same lung have been described. To our knowledge, cases of meningothelial nodules with disseminated bilateral pulmonary involvement associated with clinical symptoms of restrictive pulmonary disease and radiologic evidence of diffuse reticulonodular pulmonary infiltrates have not been previously documented. We have studied 5 patients presenting with diffuse bilateral pulmonary involvement by numerous minute pulmonary meningothelial nodules. The patients were 4 women and a man aged 54 to 75 years who presented clinically with dyspnea and shortness of breath and the lesions were discovered on open lung biopsies performed for the evaluation of diffuse bilateral interstitial lung infiltrates found on chest x-rays and computed tomography scans. In 3 patients, there was a previous history of malignancy and the radiologic findings were suspected of representing diffuse metastatic disease. Histologically, the lesions were composed of small clusters of epithelioid cells with round to oval nuclei devoid of atypia and surrounded by abundant eosinophilic cytoplasm. Immunohistochemical studies showed positivity of the tumor cells for epithelial membrane antigen and vimentin, and negative staining for cytokeratin, actin, S-100 protein, CD34, chromogranin, and synaptophysin. Electron microscopic examination in 1 case confirmed the ultrastructural features of meningothelial cells, including complex cytoplasmic interdigitations joined by well-developed desmosomes and abundant intracytoplasmic intermediate filaments. The diffuse bilateral involvement of lung parenchyma in the present cases can lead to confusion on clinical and radiologic grounds with a variety of interstitial pulmonary processes, including idiopathic interstitial pneumonia and lymphangitis carcinomatosa. Diffuse pulmonary meningotheliomatosis should be considered in the clinical differential diagnosis of diffuse interstitial pulmonary infiltrates.     

Primary pulmonary malignant meningioma.

Fewer than 20 cases of primary pulmonary meningioma have been reported. Most of these cases have been histologically and clinically benign. We report an unusual case of primary pulmonary malignant meningioma with atypical histologic features and malignant behavior. A computed tomography scan of the head did not show evidence of tumor. The right upper lobe mass was resected and showed features of an atypical meningioma with loss of architectural pattern, mild nuclear pleomorphism, increased mitotic counts (up to 15 mitotic figures per 10 high power fields), and focally prominent nucleoli. Focally, cells with rhabdoid features were identified. The tumor's immunohistochemical and ultrastructural profiles were consistent with a meningioma. The tumor stained negative for estrogen and focally positive for progesterone receptors and had a MIB-1 labeling index (marker of cell proliferation) of 9.2%. Approximately 5 months after the initial resection, the patient experienced a tumor recurrence with multiple lymph node metastases, spread to the middle and lower lobes of the right lung, and metastasis to the diaphragm. Rarely, primary pulmonary meningiomas may present as high-grade malignant lesions.     

Melanocytic colonization of a meningothelial meningioma: histopathological and ultrastructural findings with immunohistochemical and genetic correlation: case report

OBJECTIVE AND IMPORTANCE: Melanocytic colonization of nonpigmented extracranial tumors has been reported in adenocarcinomas, squamous cell carcinomas, skin appendage tumors, and dermatofibrosarcoma protuberans. To our knowledge, melanocytic colonization of a meningioma has not previously been described. CLINICAL PRESENTATION: We report an unusual case of a 70-year-old African-American woman who presented with a large frontoparietal meningioma that extended through the calvarium. INTERVENTION: Craniotomy with gross total resection of the tumor was performed. Histochemistry, immunocytochemistry, ultrastructural analysis, and molecular genetic study via fluorescence in situ hybridization confirmed melanocytic colonization of a meningothelial meningioma. CONCLUSION: With the inclusion of meningothelial meningioma, the spectrum of tumors affected by melanocytic colonization continues to expand.     

Pulmonary meningioma. Immunohistochemical and ultrastructural features

Two cases of solitary primary pulmonary tumors showing the immunohistochemical and ultrastructural features of meningothelial meningiomas are presented. The benign clinical and radiologic course, the negative computed tomography scan of the brain (case 1), and negative neuropathologic investigation (case 2) support the diagnosis of a primary pulmonary meningioma rather than a metastazing malignant intracranial meningioma. Negative neuroendocrine markers (neuron-specific enolase, chromogranin, bombesin) and the lack of neurosecretory granules by electron microscopy confirm the diagnosis of this rare pulmonary tumor.     

Histologic variants of papillary and follicular carcinomas associated with anaplastic spindle and giant cell carcinomas of the thyroid: an analysis of rhabdoid and thyroglobulin inclusions

We describe the histologic variants of papillary and follicular carcinomas associated with 109 spindle and giant cell carcinomas (SGCC) of the thyroid and determine the incidence of rhabdoid and thyroglobulin inclusions in these tumors. In addition, we searched for rhabdoid and thyroglobulin inclusions in 120 papillary carcinomas (PC) (all 15 variants included), 23 differentiated follicular carcinomas (DFC), (6 with insular pattern), 6 poorly differentiated follicular carcinomas (PDFC) and 34 follicular adenomas (FA). The following differentiated thyroid carcinomas coexisted with SGCC: 51 (46.8%) PC, (34 conventional type, 14 tall cell variant and 3 follicular variant), 6 (5.5%) DFC, 1 follicular carcinoma with insular pattern (0.9%), and 3 oncocytic carcinomas (2.8%). Eleven SGCC (10%) and 2 (33%) PDFC showed rhabdoid features, but lacked thyroglobulin inclusions. Thyroglobulin inclusions were found in 10 FA (29%), 8 (17%) follicular variants of PC and in 7 (30.4%) DFC. There were no rhabdoid inclusions in any of these differentiated thyroid tumors. Our findings support the hypothesis that most SGCC result from dedifferentiation or anaplastic transformation although the mechanisms that underlie this transformation remain unknown. The finding that only 1 (0.9%) SGCC was associated with follicular carcinoma with insular pattern contradicts the opinion that this tumor occupies an intermediate position between differentiated and anaplastic carcinomas. Rhabdoid features are markers of PDFC and SGCC while thyroglobulin inclusions are markers of FA and differentiated thyroid carcinomas with follicular phenotype.     

Early malignant transformation of a petroclival meningothelial meningioma

Although some authors have reported the malignant transformation of meningiomas, there has been no previous report describing that a meningothelial meningioma transformed into an atypical meningioma within 1 year. This report documents a 57-year-old woman who presented with right hearing disturbance. Magnetic resonance imaging revealed a right petroclival meningioma. The tumor was subtotally removed and was diagnosed to be a meningothelial meningioma. Seven months after surgery, a recurrence of the tumor was confirmed. The diagnosis of this recurrent tumor was an atypical meningioma. The MIB-1 index and the percent of p53 protein-positive cells in the primary tumor were 4.6% and 35.4%, respectively, whereas those of the recurrent tumor were 34.7% and 33.1%, respectively. A chromosomal DNA copy number loss was observed on 1p, 6q, 10, 14q, and −22q detected in both the primary and the recurrent tumors. These results suggest that the present case had a potentially malignant tumor in the early stage, although it had the histological features of benign meningiomas. An evaluation of the MIB-1 index, as well as the expression of p53 and chromosomal aberrations, may be useful for predicting the malignant transformation of meningiomas.     

Malignant rhabdoid meningioma arising in the setting of preexisting ganglioglioma: a diagnosis supported by fluorescence in situ hybridization. Case report

A highly malignant brain neoplasm with rhabdoid morphological features emerged in the bed of a subtotally resected ganglioglioma in a 54-year-old retired nuclear submarine officer. A combined application of neuroimaging, immunohistochemical studies, electron microscopy, and fluorescence in situ hybridization (FISH) was used to establish the morphological identity of the tumor. The rhabdoid appearance of the tumor cells indicated either an especially malignant variant of rhabdoid meningioma or an atypical teratoid/rhabdoid tumor with an unusually late onset. Whereas immunohistochemical studies and electron microscopy could only be used to narrow down the differential diagnosis, FISH revealed loss of one copy of NF2 with preservation of the INI1 region on 22q, thus establishing the identity of the tumor.     

Signet Ring Cell Differentiation in Salivary Duct Carcinoma with Rhabdoid Features: Report of Three Cases and Literature Review

Salivary duct carcinoma with rhabdoid features (SDCRF) is a rare salivary tumor with poor prognosis and is proposed as a salivary counterpart of pleomorphic lobular carcinoma of the breast (PLCB). Here, we report three cases of SDC with rhabdoid features (SDCRF) mimicking PLCB. Pleomorphic adenoma (PA) component was accompanied in all the cases confirming carcinoma ex PA. One patient had frequent rhabdoid features and showed invasive growth into the surrounding tissue. The other two patients had intracapsular tumor but with rhabdoid features. The patients with intracapsular SDCRF survived for > 5 years after surgery with no evidence of recurrence, whereas the patient with extracapsular SDCRF died 10 months after biopsy, and autopsy revealed disseminated metastasis to the central nervous system. Histologically, tumor cells in all three cases resembled PLCB, with a discohesive appearance, abundant cytoplasm, enlarged hyperchromatic nuclei, and similar immunohistochemical profiles, namely loss of membranous E-cadherin, obscured expression of membranous β-catenin, diffuse positivity of androgen receptor, gross cystic disease fluid protein-15, mitochondrial adenosine triphosphate synthase subunit β, MUC1, and INI-1. Estrogen and progesterone receptors were negative, and HER2 immunoreactivities were variable. The tumor cells of extracapsular invasive SDCRF exhibited higher MIB-1 labeling index and more frequent intracytoplasmic lumina than those of intracapsular SDCRF. Ultrastructurally, rhabdoid cells contained intracytoplasmic lumina with microvillous structure, analogous to those reported in PLCB. No intracytoplasmic intermediate filament aggregation was observed. These observations indicate that SDCRF is a salivary counterpart of PLCB and under signet ring cell differentiation.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01186-4) contains supplementary material, which is available to authorized users.     

Pyrogenic cytokine interleukin-6 expression by a chordoid meningioma in an adult with a systemic inflammatory syndrome. Case report and review of the literature

Chordoid meningioma is a rare meningothelial tumor characterized by chordoma-like histological features with lymphoplasmacellular infiltration. This tumor is often seen in children, but not in adults, with a systemic inflammatory syndrome (iron-resistant microcytic anemia and/or dysgammaglobulinemia) and very rarely with a persistent moderate hyperthermia. In the present report the authors describe a temporal chordoid meningioma in a 30-year-old woman who presented with fever, headache, and a serological inflammatory syndrome. The clinical symptomatology, chiefly the fever, disappeared immediately after removal of the tumor. To the authors' knowledge, only one similar patient with such clinical presentation and response to surgery has been mentioned in the literature. Interestingly, at immunohistochemical examination, the neoplasm showed focal positivity for the pyrogenic cytokine interleukin-6. The capacity of the tumor to produce this pyrogenic cytokine could explain both the patient's clinical presentation and her response to the surgical management.     

Primary meningeal sarcomas with leiomyoblastic differentiation: a proposal for a new subtype of primary meningeal sarcomas

Two cases of primary meningeal sarcoma with leiomyoblastic differentiation are presented. In case no. 1, the tumor showed anaplastic spindle cell tumor components intermingled with anaplastic meningothelial components. Meningothelial tumor cells gradually became transformed into spindle tumor cells. Spindle tumor cells reacted with antisera to muscle actin (HHF-35) and alpha-smooth muscle actin. However, unchanged meningothelial tumor cells did not react with the antisera to HHF-35 and alpha-smooth muscle actin. Electron microscopy showed condensations of cytoplasmic fibers and pinocytotic vesicles in spindle tumor cells similar to those seen in smooth muscle cells. In case no. 2, the tumor cells consisted predominantly of sheets of round or polygonal cells as seen in an epithelioid leiomyosarcoma. The neoplastic cells had frequent nuclear inclusions, such as those seen in meningiomas. Immunohistochemically, the tumor cells reacted with antisera to desmin and to HHF-35. Electron microscopy showed a basal lamina around the cytoplasm of tumor cells. Intranuclear inclusions with various cytoplasmic organelles were frequently observed in the tumor cells, as in meningiomas. Interdigitating cytoplasmic processes and intercellular junctional complexes, however, were not found in the tumor cells. Two possible hypotheses explain the occurrence of leiomyoblastic characteristics of these cases. In case no. 1, leiomyoblastic cells originated from meningothelial cells with the advancement of meningothelial anaplasia. In case no. 2, pluripotential mesenchymal cells in the meninges differentiated into meningothelial and smooth-muscle cell lines at the time of tumor growth. With consideration of previous publications on primary meningeal sarcoma, these cases are the first reported primary meningeal sarcoma with leiomyoblastic and meningothelial differentiation.     

A new subtype of meningioma

Three patients with small meningiomas presented with diffuse cerebral edema that was out of proportion to the size of tumors. All lesions were small and no brain invasion or unusual tumor vascularity or dural sinus involvement was noted in any of the three cases. Tumor material was subjected to conventional and immunohistochemical stains. All three tumors showed benign meningothelial components, prominent formation of hyaline inclusions (pseudopsammoma bodies), and striking vascular mural proliferation of small dark cells. All patients have remained asymptomatic without any evidence of tumor recurrence after a follow-up of 4-6 years. These tumors showed proliferation of pericytes in blood vessel walls and, therefore, represent a new subtype of meningothelial meningioma. In the study presented here, the location, size, histotype, and clinical findings that may influence the development of peritumoral brain edema are discussed in detail.     

Chordoid meningioma with polyclonal gammopathy. Case report

The authors present a case of chordoid meningioma in a 55-year-old woman who manifested headache and personality change. Magnetic resonance imaging of the brain and cerebral angiography demonstrated a mass in the right frontal lobe that resembled a typical convexity meningioma. However, the pathological diagnosis was chordoid meningioma, a rare subtype of this tumor that usually occurs in adolescence and is known to be associated with Castleman syndrome. A meningothelial meningiomatous pattern suggestive of a meningothelial origin was focally present, and cytokeratin-positive squamoid cells were noted in the tumor. The lesion lacked dense infiltration of lymphocytes and plasma cells. Polyclonal gammopathy was the only sign of Castleman syndrome and hypochromic microcytic anemia was absent in this case. Polyclonal gammopathy resolved completely 6 months after total removal of the mass.     

Suprasellar primary malignant rhabdoid tumor in an adult: a case report

Malignant rhabdoid tumor (MRT), described for the first time in 1978 in the kidney, has rarely been reported in other organs including the brain and has involved adults in only 3 cases. We described a case of MRT in a 32-year-old woman who presented with severe headache, nausea and sudden onset of visual disturbance. MRI showed a well-enhanced mass at the suprasellar region. Subtotal removal of the tumor was performed. However, tumor regrowth occurred after the operation (doubling time, 8.36 days) and spinal dissemination was detected. Therefore, chemotherapy and radiotherapy were administered focusing on the suprasellar lesion and the spinal cord. Pathologically, light micrographs showed rhabdoid cells with large, round, single or double nuclei with one prominent nucleolus and eosinophilic cytoplasmic inclusions. Electron micrographs were made of typical rhabdoid cells displaying bundles of intermediate filaments within the perikaryon. In immunohistochemical studies, EMA, vimentin, cytokeratin and SMA were positive. Pathological findings were consistent with those of MRT. Optimal treatment for this tumor has not been established. Our case may be useful in defining treatment for MRT.     

Lipomatous meningioma: a clinicopathologic study of 18 cases with special reference to the issue of metaplasia

We report 18 cases of lipomatous meningioma occurring in patients aged 14 to 79, most being females (72%). Sixteen were supratentorial and 2 involved the spinal meninges. Follow-up ranged from 1 to 120 months. Fifteen patients were cured with surgery alone and 3 (17%) experienced a recurrence at 7, 8 and 24 months. Of these, one died with disease 4 years after resection of the primary lesion. Histologically, 12 tumors were meningothelial, 3 transitional, 2 showed myxoid stromal changes and 1 was microcystic. The 2 spinal tumors were atypical. The proportion of fatty cells ranged from 10 to 90%. These resembled mature adipocytes or less commonly lipoblasts. Xanthomatous meningothelial cells were also noted in 6 tumors (30%). Both conventional meningothelial as well as lipid-laden cells exhibited epithelial membrane antigen immunoreactivity. In addition, occasional cells resembling mature adipocytes showed reactivity for S-100 protein. Ultrastructurally, lipidization of neoplastic cells varied from intracytoplasmic lipid droplets to a single massive globule. Moreover, lipid-laden meningothelial cells featured interdigitating cell membranes and well-formed desmosomes. Lipid droplets were not membrane-bound. In that metaplasia denotes differentiation of one mature cell type to another, lipid accumulation in meningiomas cannot be considered true metaplasia since their lipid-laden cells retain the immunophenotype and ultrastructural features of meningothelium. We suggest that this distinctive subset of meningiomas be termed "lipidized meningiomas" rather than being included in the metaplastic category.