Desmoplastic cerebral astrocytomas of infancy: A histopathologic, immunohistochemical, ultrastructural, and molecular genetic study

The desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor that presents as a large hemispheric mass in infants. Despite an ominous histologic picture that may resemble a sarcoma, the tumor is astrocytic and has a good prognosis. We present two cases of DCAI, with histopathologic, immunohistochemical, ultrastructural, and molecular genetic data, and draw the following conclusions: (1) the diagnosis of DCAI requires a high index of suspicion and immunohistochemical or ultrastructural proof of astrocytic differentiation; (2) the data argue against nosologically equating these tumors with the desmoplastic infantile ganglioglioma, pleomorphic xanthoastrocytoma, or gliofibroma; (3) the components of the extensive tumor basal lamina may be elaborated by the tumor cells themselves and may contribute in an autocrine fashion to the slow growth of these lesions; and (4) if the lack of allelic loss on chromosomes 17p (including the p53 tumor suppressor gene locus) and 10 seen in our cases is found in other cases of DCAI, this may further distinguish the DCAI from other astrocytomas.     

Recurrent subependymoma of fourth ventricle with unusual atypical histological features: A case report

Subependymoma is a rare subtype of benign ependymal neoplasm with distinct histological features. Anaplastic transformation has not yet been reported in this tumor to date. We present here a very unusual case of a 62‐year‐old woman with recurrent subependymoma of the fourth ventricle with multiple atypical histological features. Histologically, the resected recurrent tumor showed characteristic small cell clusters and nests of ependymal cells with an interspersed gliofibrillary matrix as seen in a classic subependymoma. In addition, there were very unusual histological features, including multiple areas of necrosis, microvascular proliferation, thrombosed blood vessels, and scattered mitotic figures. No coexisting ependymoma component of higher World Health Organization (WHO) grade was present. Immunohistochemically, MIB‐1 labeling index was high, with up to 15% in the highest areas. Review of this patient's initial tumor, which was resected 6 years prior to recurrence, demonstrated features of a typical classic subependymoma without atypical features or a secondary tumor component. Subependymomas are known to be low‐grade tumors and are usually cured if completely excised. The tumor presented here is unique in that several atypical pathological features were found in an otherwise typical subependymoma. Our case may represent anaplastic transformation of subependymoma, although no such examples have been reported to date.     

Pleomorphic rhabdomyosarcoma in children: four cases in the pediatric age group

Pleomorphic rhabdomyosarcoma is considered rare and controversial, especially in children. Although pleomorphic rhabdomyosarcoma has been observed in children, its sparcity has taken it out of current childhood rhabdomyosarcoma classifications. We report four pediatric cases of pleomorphic rhabdomyosarcoma, review morphologic, immunohistochemical, and ultrastructural features, and discuss the rare need to include this category in children. The Soft Tissue Registry of the Armed Forces Institute of Pathology was searched for cases coded as "pleomorphic rhabdomyosarcoma" from 1970 to the present. Only cases in patients less than 21 years old were included. Clinical data, morphology, and immunohistochemical stains were reviewed and follow-up was obtained. Electron microscopy was performed on two cases. Molecular analysis by polymerase chain reaction was performed on one case with available material. Of four patients included, there were three boys and one girl. Patient ages ranged from 9 months to 10 years (median, 4.5 years). Tumors were located on the chest wall (n = 2) and one each on the upper and lower extremities. Tumor size ranged from 4.0 to 10.0 cm (median, 7 cm). Grossly, the tumors were lobulated and circumscribed. Microscopically, architectural patterns varied from solid to fascicular or storiform. All tumors had large, often multinucleated, polygonal, spindled or strap-like rhabdomyoblasts with abundant eosinophilic cytoplasm. Nuclear characteristics ranged from hyperchromatic to vesicular. Most tumor cells had large prominent nucleoli. Background rhabdomyoblasts varied from spindled to polygonal. No tumors displayed areas typical of embryonal or alveolar rhabdomyosarcoma. All tumors exhibited atypical mitotic figures. Immunohistochemistry revealed that the tumors were positive for the following markers: desmin (3/4), myoglobin (4/4), myoD1 (3/3), myf4 (3/3), and MSA (4/4). The two cases studied by electron microscopy both showed evidence for skeletal muscle differentiation. One case showed no evidence for a t(2;13) or t(1;13) translocation. Two patients were alive with no evidence of disease at 12 and 25 years. One patient was dead of disease at 9 years. Pleomorphic rhabdomyosarcoma is rare but exists in children. The diagnosis should be considered in pleomorphic sarcomas exhibiting skeletal muscle differentiation, which are otherwise devoid of typical areas or chromosomal changes of embryonal or alveolar rhabdomyosarcoma.     

Malignant myoepithelioma of the parotid gland: cytologic and histologic features

A case of malignant myoepithelioma of the parotid gland in a 34-year-old female is presented. In the fine-needle aspiration material, there was predominance of poorly cohesive polygonal cells with marked nuclear pleomorphism; no mitotic figures were observed. Focally, fragments of myxoid metachromatic intercellular material were also present. Histologically, the tumor was encepsulated, showing focal invasion of the capsule and tumor thrombi in the capsular vessels. The tumor was predominantly solid and myxoid, composed of cells with epithelioid features, marked anisonucleosis and a low mitotic activity. Immunohistochemically, the cells revealed positive staining for S-100 protein, vimentin, cytokeratins, glial acidic fibrillary protein and carcinoembryonic antigen; only several cell groups expressed smooth muscle actin and desmin; muscle specific actin was uniformly negative. In differential diagnosis, it was important to distinguish malignant myoepitelioma mainly from pleomorphic adenoma (mixed tumor), benign myoepithelioma, carcinoma ex pleomorphic adenoma and malignant melanoma. The criteria of malignancy in myoepithelial tumors are discussed.     

Pleomorphic xanthoastrocytoma: report of a case with light and electron microscopy

A case of pleomorphic xanthoastrocytoma is reported with light and electron microscopic findings. This unusual tumor arose in a 15-year-old male. The tumor consisted predominantly of nests of xanthomatous cells and plump spindle cells surrounded by a prominent reticulin network. There was considerable cellular pleomorphism with abundant bizarre giant cells and multinucleated cells. Occasional mitoses were present. Electron microscopy and immunoperoxidase localization of glial fibrillary acidic protein (GFAP) confirmed the glial nature of the tumor. Recognition of this tumor is important. Despite its “malignant” appearance, the tumor characteristically has a relatively good prognosis and should not be confused with highgrade gliomas or meningeal sarcomas, which require aggressive therapy.     

Suprasellar giant cell ependymoma: a rare neoplasm in a unique location

Ependymomas are glial tumors that usually present in the posterior fossa in children and in the spinal cord in adults. Giant cell ependymoma, a rare ependymal subtype only recently recognized as a diagnostic entity in the last decade, demonstrates pleomorphic giant cells admixed with features of typical ependymoma. Although only 8 giant cell ependymomas have been reported to date, none have been reported in the suprasellar space. Moreover, as these neoplasms demonstrate a high incidence of anaplastic grade, recognition of this ependymal subtype is paramount. We describe the presentation and pertinent radiologic, histologic, immunologic, and ultrastructural findings in conjunction with relevant clinical implications of the first reported case of a suprasellar giant cell ependymoma occurring in a 34-year-old female 7 years after an initial diagnosis of a medullary ependymoma with rare atypical giant cells, a potential tumor seeding culprit.     

Primary osseous rhabdomyosarcoma with focal matrix formation mimicking osteosarcoma

We present an unusual case of primary osseous pleomorphic rhabdomyosarcoma with focal matrix formation mimicking osteosarcoma. The patient was a 21-year-old man who had suffered from pain and slight enlargement of his left calf for 2 months. A plain radiograph demonstrated a large, predominantly osteolytic mass in the region of the proximal fibula with features typical of malignant primary bone tumor. On open surgical biopsy, the tumor consisted of atypical cells, some of them presenting spindle morphology. Between them, there were bands of densely hyalinized matrix with osteoid appearance, but without definite lacunae or calcifications, and an osteosarcoma was diagnosed. Consequently, the tumor was removed. The postoperative tissue presented more pleomorphic cells with some definite rhabdomyoblasts. Desmin, actin, Myf4, and MyoD1 were positive in tumor cells, and a diagnosis of rhabdomyosarcoma was eventually made. Only few cases of primary pure bone rhabdomyosarcoma have been reported. Other bone tumors with rhabdomyosarcomatous differentiation have been described: dedifferentiated chondrosarcoma, fibrosarcoma, and osteosarcoma. Our case does not meet the criteria for sclerosing rhabdomyosarcoma, as matrix formation is focal and cells are spindle-shaped and pleomorphic. However, it is a further example of a diagnostic error in connection with primary osseous tumor.     

Primary malignant mixed mesodermal tumor of the gallbladder

Summary A rare case of primary malignant mixed mesodermal tumor of the gallbladder arising in a 75 year old woman is reported. The previously published cases of similar tumors were reviewed in order to outline the histological features and the histogenesis. In diagnosing a malignant mixed mesodermal tumor of the gallbladder it was imperative that we excluded malignant neoplasms with multiple histological patterns. The diffuse and close intermingling of the epithelial and mesenchymal component ruled out a collision tumor. The high mitotic rate, the typical reticulin pattern and the obviously malignant osteoblasts excluded a spindle cell carcinoma with osseous metaplasia. The authors conclude that this is the first case of malignant mixed mesodermal tumor with evident osteosarcomatous areas, described in the gallbladder.     

A case of a pleomorphic hyalinizing angiectatic tumor of soft parts with intracytoplasmic hemosiderin pigment apparent upon fine‐needle aspiration cytology

Pleomorphic hyalinizing angiectatic tumors of soft parts are extremely rare low‐grade mesenchymal lesions that frequently occur subcutaneously, especially in the lower extremity. The tumor is histologically characterized by sheets of plump, spindled or rounded cells, and clusters of ectatic blood vessels. It also has a number of previously characterized cytological features such as pleomorphic cells, intranuclear pseudoinclusion, and intracytoplasmic hemosiderin pigments. However, intracytoplasmic hemosiderin has not been carefully evaluated in cytology specimens. Here, we report the case of a 56‐year‐old Japanese man with an encapsulated pleomorphic hyalinizing angiectatic tumor of soft parts that included fine and coarse hemosiderin‐laden tumor cells. The tumor was clinically followed up as a hematoma, but malignant tumors, including malignant melanoma, were suspected because aspiration cytology specimens contained pleomorphic cells with intracytoplasmic brown pigments. The tumor was closely associated with an intratumoral hematoma and a few microscopic satellite lesions. Pleomorphic hyalinizing angiectatic tumor of soft parts should be included in the differential cytological diagnosis of soft tissue tumors if the three cytological features described earlier are present. Enucleation therapy could facilitate local recurrence, as the tumor may have the potential to infiltrate surrounding soft tissue or form satellite lesions. Diagn. Cytopathol. 2015;43:407–411. © 2014 The Authors. Diagnostic Cytopathology Published by Wiley Periodicals, Inc.     

脑多形性黄色瘤型星形细胞瘤的临床病理观察

目的 探讨多形性黄色瘤型星形细胞瘤（PXA）的临床病理特征、诊断及鉴别诊断、治疗及预后。方法 对南京军区南京总医院1980-2004年间6287例中枢神经系统肿瘤中的15例PXA（0．2％）,以及2例会诊病例,进行临床病理学观察,免疫组织化学SP法检测8种抗体的表达：胶质纤维酸性蛋白、波形蛋白、S-100、上皮细胞膜抗原、突触素、神经微丝、CD68及CD34,获得其中10例的随访资料。结果 患者年龄12～55岁,平均30．8岁,男6例,女11例。主要症状为癫痫发作、头痛、头晕等。肿瘤发生于幕上者16例,占94．1％,其中发生于颞叶者7例,占41．2％。肿瘤大小2—7cm,平均4．3cm,9例有囊性变。除2例会诊病例外,全切除12例,次全切除3例。随访10例,生存8例,生存时间10个月- 13年7个月,平均生存6年,生存10年以上者2例。组织学特征为：单核或多核巨怪瘤细胞、梭形细胞和泡沫样瘤细胞混合而成,肿瘤中有丰富的网状纤维及淋巴细胞浸润,缺乏坏死,核分裂象无或少。胶质纤维酸性蛋白、波形蛋白及S-100蛋白免疫组织化学染色均呈弥散阳性表达,CD34阳性率为77％。1例伴有间变特征的PXA,有较多核分裂象（≥5个／10HPF）。2例有脑实质及血管周围间隙的浸润。1例影像学检查提示肿瘤复发及脑膜播散。结论 PXA属WHOII级肿瘤,肿瘤全切除及组织学为典型性PXA者预后较好,少数PXA可复发及间变。瘤细胞巨大、怪异,容易误诊为WHOⅣ级的巨细胞胶质母细胞瘤,两者的鉴别要点在于PXA部分可见泡沫样瘤细胞,核分裂象无或少,缺乏坏死。瘤细胞CD34的阳性表达有助于PXA的诊断。     

Desmoplastic cerebral astrocytoma of infancy: a case report.

We present a case of desmoplastic cerebral astrocytoma of infancy (DCAI) in a 9-month-old boy including immunohistochemical and proliferative activity studies. It was mainly composed of glial fibrillary acidic protein (GFAP)-positive astrocytes and desmoplastic stroma. Studies with Ki-67 and synthetic phase fraction disclosed a low proliferative activity. Flow cytometric study revealed diploidy pattern. These findings suggest a positive correlation with the favorable prognosis.     

Cytomorphological features of salivary duct carcinoma ex pleomorphic adenoma: diagnosis by fine-needle aspiration biopsy with histologic correlation.

We report a case of salivary duct carcinoma arising from a pleomorphic adenoma (ex pleomorphic adenoma) in a parotid salivary gland of a 70-yr-old man. Fine-needle aspiration biopsy showed two distinct subsets of cells. There was the typical biphasic pattern of pleomorphic adenoma consisting of bland epithelial cells admixed with uniform spindle-shaped cells and chondromyxoid stroma. In addition, there were features of salivary duct carcinoma best demonstrated by necrosis and the presence of large polygonal cells arranged either singly or in rosettes, clusters or sheets reminiscent of ductal carcinoma of the breast. This case illustrates that the presence of background large polygonal cells and necrosis in an otherwise typical pleomorphic adenoma may suggest the diagnosis of a high-grade carcinoma, namely salivary duct carcinoma, which portends poor prognosis and requires aggressive treatment. Differential diagnosis from other carcinomas known to arise in pleomorphic adenoma is discussed.     

Malignant pleomorphic adenoma (malignant mixed tumor) of the trachea. Report of a case

Malignant pleomorphic adenoma arising in the trachea has not been reported in the literature. We report here a case of malignant pleomorphic adenoma (malignant mixed tumor) occurring in the trachea of a 65-year-old woman. The tumor metastasized to the lung and the chest wall 11 years after complete resection of the primary tumor, which was a polypoid submucosal tumor, 1.3 cm in diameter. Light microscopic examination of the primary and metastatic tumors showed the presence of epithelial and stromal elements, consisting of grandular structures, foci of squamous metaplasia and a myxochondroid stroma. Many tumor cells showed myoepithelial cell features by electron microscopy, and immunoreactivity for S-100 protein and GFAP was also seen in many of them. These findings were consistent with those of pleomorphic adenoma. However, the epithelial elements were cytologically atypical with prominent mitotic figures. Infiltration of the tumor cells into the surrounding soft tissue was also seen. No foci of benign pleomorphic adenoma were found in the primary tumor. These findings indicate that this tumor was not a carcinoma ex pleomorphic adenoma, but a true malignant pleomorphic adenoma (true malignant mixed tumor) of the trachea.     

Cytologic features of fibrolamellar carcinoma with mucin production: A rare variant of combined hepatocellular‐cholangiocarcinoma

Fibrolamellar carcinoma (FC) is an uncommon tumor that usually arises in non‐cirrhotic livers of adolescents or young adults. It differs clinically from hepatocellular carcinoma in its better prognosis and lack of gender predilection. Cytologically, the tumor is composed of large polygonal cells with abundant cytoplasm, pleomorphic nuclei, and prominent large nucleoli. A variant of FC with mucinous differentiation has been previously described. These tumors have been regarded as combined hepatocellular cholangiocarcinomas. Herein, we report the case of a 44‐year‐old Asian female with a large liver mass present for approximately two years. Core needle biopsy with imprint cytology demonstrated FC with areas of intracellular mucin. To our knowledge, cytological features of this rare tumor have not been described before. Diagn. Cytopathol. 2014;42:431‐435. © 2012 Wiley Periodicals, Inc.     

MALIGNANT PLEOMORPHIC ADENOMA (MALIGNANT MIXED TUMOR) OF THE TRACHEA. Report of a Case

Malignant pleomorphic adenoma arising in the trachea has not been reported in the literature. We report here a case of malignant pleomorphic adenoma (malignant mixed tumor) occurring in the trachea of a 65-year-old woman. The tumor metastasized to the lung and the chest wall 11 years after complete resection of the primary tumor, which was a polypoid submucosal tumor, 1.3 cm in diameter. Light microscopic examination of the primary and metastatic tumors showed the presence of epithelial and stromal elements, consisting of grandular structures, foci of squamous metaplasia and a myxochondroid stroma. Many tumor cells showed myoepithelial cell features by electron microscopy, and immunoreactivity for S-100 protein and GFAP was also seen in many of them. These findings were consistent with those of pleomorphic adenoma. However, the epithelial elements were cytologically atypical with prominent mitotic figures. Infiltration of the tumor cells into the surrounding soft tissue was also seen. No foci of benign pleomorphic adenoma were found in the primary tumor. These findings indicate that this tumor was not a carcinoma ex pleomorphic adenoma, but a true malignant pleomorphic adenoma (true malignant mixed tumor) of the trachea. ACTA PATHOL JPN 38: 1215∼1226, 1988.     

Cytomorphology of glioblastoma metastic to a cervical lymph node diagnosed by fine needle aspiration (FNA): A case report and review of literature

Glioblastoma is an aggressive primary central nervous system tumor with a dismal prognosis. However, extracranial metastases are extremely rare. Very few cases have been reported in the literature. We present a case of a 64‐year‐old male with glioblastoma metastatic to a cervical lymph node in which the diagnosis was made on fine needle aspiration cytology (FNAC). The cytomorphologic features of glioblastoma are distinct, with pleomorphic cells in loosely cohesive clusters with prominent nucleoli, coarsely clumped chromatin and cellular processes. We suggest that FNAC, along with clinical history, is a cost effective, safe, and diagnostically accurate method of diagnosing glioblastoma metastases. Cell block is also helpful in establishing the diagnosis.     

Desmoplastic astrocytoma of infancy--a case report

Desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor which shows spindle cells embedded in an extremely desmoplastic stroma. We describe a case of DCAI seen in the frontoparietal region of brain in a three-month-old infant. Microscopically classic histology of DCAI was seen. On immunohistochemistty the tumor showed strong Vimentin, S-100 and Glial Fibrillary Acidic Protein (GFAP) positivity. The brain adjacent to the tumor-showed multi-cystic transformation and the tumor formed a solid area in the wall of this cystic structure. This adjacent brain showed mild disarray of architecture and gliosis. Three months after surgery this infant was alive and well.     

Cytopatholologic features of gliosarcoma with areas of primitive neuroepithelial differentiation of the brain in squash smears

Gliosarcoma with areas of primitive neuroepithelial differentiation (GSPNED) is an extremely rare neoplasm. A case is presented here in which squash smears of a left temporal lobe tumor in a 76‐year‐old male demonstrated two distinct and easily recognizable cellular populations, i.e., densely hyperchromatic cells of a primitive nature in a fibrillary background and pleomorphic spindle‐shaped cells. Occasional pseudo‐rosette formations and nuclear cannibalism suggestive of neuroendocrine differentiation were also found. A cytologic diagnosis of a malignant tumor was suggested, and histochemical and immunohistochemical studies were conducted on formalin‐fixed, paraffin‐embedded material. Reticulin stain highlighted increased intercellular collagen and reticulin deposition within the spindled regions, whereas nodules with primitive cells were reticulin‐poor. There was a diffuse and strong reactivity to neuron specific enolase, synaptophysin and CD56 immunostains. A stain for glial fibrillary acidic protein and S‐100 protein demonstrated a subset of tumor cells including elongated cytoplasmic processes. The spindled component was positive for vimentin and smooth muscle actin, whereas the primitive‐appearing tumor cells were negative. The diagnosis of GSPNED was confirmed based on cytopathologic, histopathological and immunohistochemical results. The cytomorphologic features of this distinctive tumor are illustrated, and the adjunctival value of squash smears for frozen‐section diagnosis is also discussed. This is the first presentation of a cytopathologic analysis that provides an important clue to an accurate diagnosis of GSPNED. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Immunohistochemical analysis of giant cell glioblastoma

Giant cell glioblastoma (GCG) is one of a group of rare tumors in which the cell population is abnormally large and includes multinucleated cells of gigantic sizes. Immunohistochemical studies were performed on four GCG cases and found that all giant cells and/or tumor cells were positive for glial fibrillary acidic protein (GFAP), S-100 protein, and vimentin, thus verifying the tumor's glial origin. The nuclei of multinucleated giant cells of three adult cases were frequently immunostained for proteins expressed during the cell cycle (proliferating cell nuclear antigen (PCNA) and Ki-67), thereby demonstrating the proliferative capacity of these cells. By contrast, those of a 12 year old girl expressed these cell cycle markers rather infrequently. Alpha I-anti-trypsin was detected with relatively high frequency in the giant cells, and its presence may explain their bizarre sizes and pericellular reticulin fiber formation. A literature review of 32 cases revealed that the GCG that occurs preferentially in young girls is a type of pleomorphic xanthoastrocytoma. By contrast, GCG in adult males has the same age incidence as ordinary glioblastomas and, as these, expresses high levels of cell cycle-related proteins. Thus, GCG, which is subclassified morphologically as ordinary glioblastoma, has distinct biological and clinical characteristics, with that in children requiring re-evaluation because of its similarities to pleomorphic xanthoastrocytoma.