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Epithelioid hemangioma (EH) is a rare benign vascular lesion, characterized by endothelial cells with epithelioid/histiocytoid appearance. Heart involvement is extremely rare. We present an unusual case of cardiac EH in a young woman with supraventricular arrhythmia, nephrotic syndrome (membranous glomerulopathy), and peripheral eosinophilia after a pregnancy and normal partum resembling Kimura disease. Echocardiogram showed a large tumor mass in the right cardiac ventricle. The cardiac tumor was removed and the histopathology revealed an endothelial proliferation associated with abundant eosinophils. The neoplastic endothelial cells were eosinophilic and polygonal with epithelioid/histiocytoid morphology. Lymphoid nodules were occasionally seen. The neoplastic cells were positive for CD34, CD31, ERG, and factor VIII and negative for CK. A diagnosis of EH was rendered. The patient was alive and well after surgical resection. EH and Kimura disease represent separate entities, but clinical and/or histological overlapping can be observed. Epithelioid/histiocytoid endothelial cells constitute the hallmark feature that favors a final diagnosis of EH.

Artículo publicado en: International Journal of Surgical Pathology published online 18 July 2010 The purpose of this study was to examine the immunoexpression of cell adhesion molecules (CAMs) E-cadherin, CD44s, and CD44v3 in cervical cancer and compare it with that in benign exo-endocervical tissue. In all, 81 cervical cancer biopsy specimens and 22 benign controls were included. Primary monoclonal antibodies NHC-38, F10-44-2, and 3G5 for E-cadherin, CD44s, and CD44v3 were used, respectively. Statistical significance was evaluated by the ?2 test. Antigen expression was significantly different in cervical cancer specimens compared with controls, showing marked decrease in membrane expression: E-cadherin, 6.5% and 77.3% (P < .000); CD44s, 3.9% and 81.8% (P < .000); and CD44v3, 0% and 81.8% (P < .000), respectively. The immunoexpression was significantly heterogeneous in carcinomas (P < .034) and adenocarcinomas (P < .000) for E-cadherin and CD44s. For CD44v3, no case of cancer showed immunostaining in membranes. These findings reaffirm that cell adhesion is markedly altered in cervical cancer. The authors suggest that these proteins could serve as markers for invasive cervical neoplasia. tmorelva@ula.ve antonio.llombart@uv.es

The prevalence of human liver cancer shows a broad spectrum of variation in distinct geographical regions, depending on different risk factors, and their pathogenesis is poorly understood. We study the significance of molecular alterations of K-ras gene in human liver carcinomas in a low-incidence region such as a Mediterranean area of Spain (Valencia and Gerona). Our results reveal a low incidence of K-ras codon 12 mutations in hepatocellular carcinomas (HCC) and a higher incidence in cholangiocarcinomas (CCC). Similar results have been obtained in high-risk areas. We conclude that K-ras gene mutations are not a major event in the malignant transformation of hepatic cells in this region of the Mediterranean but that molecular implications of hepatocellular and cholangiocarcinomas appear to be different. Int J Surg Pathol 8(4):267-270, 2000

There is no agreement in the literature on selecting the principal parameters that contribute to explain the different outcomes in supratentorial astrocytomas. Hence, we designed a global study using morphologic parameters and DNA quantification measured by flow cytometry (FCM) and image analysis (IA) on 116 tumors contrasting the results with patients' survival in a univariate and multivariate study. In the Kaplan-Meier study besides the necrosis (p2/M phase, and the proliferative phase measured by image analysis (IA) or ploidy patterns did not influence the prognosis. In the Cox's proportional hazards model the presence of necrosis remained as the only prognostic predictor (p=0.001) and increased 5.9 times the risk of mortality in gliomas.

The histological diagnosis of Ewing's sarcoma (Es) continues to be a difficult task for pathologists. A number of new Es varieties has been described, leading to further complexity. Conventional Es, atypical Es, and peripheral neuroectodermal tumor (pPNET), including peripheral neuroepithelioma, belong genetically to the same family of neoplasms, displaying common chromosomal rearrangements and analogous gene reorganizations. The main translocations are t(11;22) and t(21;22), with genes EWS, FLI-1 and ERG being involved, as well as other members of the ETS family of transcription factors. The prevalence of morphology should be maintained with the use of conventional histological techniques and supported with the analysis of the expression of CD99 Mic2 (HBA 71, 0.13) antigen, which is present in over 90% of cases, as well as with FLI-1 rearranged gene derived protein. Moreover, FISH and RT-PCR in paraffin-embedded tumor tissue may be of use in extremely difficult cases for differential diagnosis. Nevertheless, a number of mixed tumor types, such as primitive sarcoma or biphenotypic sarcoma, may show structural and genetic diversity, thus rendering their diagnosis even more complex.

The pigmented variant of basal cell carcinoma (PBCC) may be clinically misinterpreted as malignant melanoma. Histologically this variant is characterized by the presence of functional melanocytes distributed among epithelial tumor cells, particularly in superficial areas. Our finding of a case of PBCC with numerous atypical HMB-45-positive melanocytes prompted us to analyze the morphologic and immunohistochemical features of 20 consecutive cases of PBCC. Four additional cases with numerous large HMB-45-positive melanocytes, also present in the most invasive tumor nests, were found. Ultrastructural examination was performed in two selected cases. Large melanocytes with immature (stages I and II) and mature melanosomes were found between epithelial tumor cells having desmosomes and tonofilaments. Our cases highlight the presence of immature melanosomes and subsequent HMB-45 immunostaining in hyperplastic melanocytes within PBCC, an underrecognized feature that should be considered to avoid a misdiagnosis of malignant melanoma.

N-myc gene amplification and/or loss of heterozygosity of chromosome 1 (LOH lp) are important criteria for prognosis and progression in human neuroblastoma (NB). Despite the high incidence of alterations of the p53 gene in human cancers, very few p53 mutations have been reported in NB. The objective of our study was to search for p53 mutations in NB and their correlation with N-myc amplification and clinical or pathologic parameters. We analyzed 14 selected cases of NB from the Spanish Protocol N-II-92. We found a missense mutation in codon 248 CGG to GGG (Arg/Gly) in one case of stage 4 NB with no N-myc amplification. Our results confirm the low incidence of p53 gene mutation in neuroblastoma and the absence of correlation with histopathologic parameters.

Small cell sarcomas of bone are difficult to classify and diagnose. The present case deals with such a tumor in which the original biopsy and the resected specimen, studied by histology before chemotherapy, provided no final information about its real nature. Thus several techniques were applied to discern its histogenesis and biology. Myogenin proved positive in isolated cells of the primary neoplasm but was extensively expressed in nude mice xenografts. Electron microscopy confirmed the existence of myofilaments. The cytogenetic analysis revealed a large number of chromo somal abnormalities, but not those found in the Ewing's/PNET (peripheral neuroectodermal tumor) family of tumors. This was confirmed by polymerase chain reaction (RT-PCR) wherein no EWS/Fli 1 or PAX3/FKHR gene rearrangements were detected. Based upon these studies, a rhabdomyosarcoma of bone was diagnosed. Clinically the neoplasm showed a highly aggressive behavior, causing death of the patient within 2 years after diagnosis.

Nongestational, nongonadal, and nonteratoma-related choriocarcinoma is an extremely rare entity. The tumor may be pure or associated with carcinoma. Six cases of primary endometrial carcinomas with the presence of syncytiotrophoblastlike beta-human chorionic gonadotropin (beta-HCG)-positive cells have been reported. We describe a case of endometrial carcinoma in a postmenopausal woman, that was composed almost entirely of syncytiotrophoblastic and cytotrophoblastic elements, except in the areas of lymphatic and myometrial invasion, where the neoplasm expressed a papillary serous carcinoma conformation with numerous psammoma bodies. There was not a clear transition between choriocarcinoma and serous carcinoma components. Immunohistochemically, beta-HCG was strongly positive in trophoblastic cells, whereas papillary areas expressed epithelial membrane antigen. These results suggest a double differentiation from malignant stem cells toward an extraembryonal germinal line and a papillary epithelial line. A poor prognosis is expected for this type of neoplasm with extraembryonic differentiation. In the present case, the histologic subtype of uterine papillary serous carcinoma could be an additional risk factor.

Eight conventional and six atypical oncocytomas in a series of 147 renal neoplasms were studied. Histopathologic findings revealed exclusively oncocytic cells, but cellular polymorphism was higher in the atypical tumors. Atypical oncocytomas presented focal necrosis, transcapsular invasion, or both. Electron microscopy showed similar findings in all cases. Immunohistochemistry of atypical oncocytomas had higher expression against proliferating cell nuclear antigen and more discontinuous immunostaining against laminin than typical ones. Flow cytometry revealed one or two aneuploid peaks in five typical and two atypical cases, although the latter had a higher proliferative fraction than typical oncocytomas. Cytogenetics of one typical oncocytoma showed a normal diploid karyotype; one atypical case resulted in a diploid karyotype but with endoreduplications in 13% of metaphases, and a second atypical oncocytoma became hypodiploid without structural anomalies. Based on the present results, the proposed distinction between conventional and atypical oncocytomas seems of limited clinical significance.

Atypical meningiomas comprise an intermediate category of meningeal neoplasmas with some microscopic features of aggressivity and a capacity for recurrence. We present a clin ical, morphologic, and cytogenetic study of 15 meningiomas. Morphologic and cytogenetic analysis suggested the existence of morphologically typical meningiomas with normal karyotype or monosomy 22 and morphologically atypical meningiomas, with increasing chromosomal abnormalities (complex karyotype) between these two types. Present results suggest the existence of a third type of morphologically typical meningioma that lacks a phenotypical aggressivity but has a complex karyotype. These genotypical characteristics may be related to the aggressivity of these neoplasms. Int J Surg Pathol 2(4):301-310, 1995