Imaging findings of ovarian dysgerminoma with emphasis on multiplicity and vascular architecture: pathogenic implications.

We report the imaging findings of three ovarian dysgerminomas that coexisted with other germ cell tumors or gonadoblastomas, focusing on the distribution of tumor nests and vascular architecture, which might provide information about the pathogenesis of dysgerminomas. In a 14-year-old female with dysgerminoma and coexisting gonadoblastomas, contrast-enhanced magnetic resonance imaging (MRI) demonstrated a solid mass in the right ovary, which presented as hyperintense lobules on diffusion-weighted imaging separated by fibrovascular septa. Some small nodules were found to exist separately from the lobules (multiplicity) and to include pathological remnants of gonadoblastoma. Large tumor vessels were present at the center of the mass (central blood vessels), which were in direct contact with the ovarian veins and radiated peripherally through the fibrovascular septa. In a 35-year-old female, a mixed germ cell tumor, which was mainly composed of dysgerminoma and yolk sac tumor foci, exhibited the same vascular architecture pattern as the first dysgerminoma on contrast-enhanced computed tomography. In a 10-year-old female with a mixed germ cell tumor, contrast-enhanced MRI revealed an enlarged left ovary, which contained a large heterogeneous mass and multiple tiny nodules (multiplicity). Microscopically, the former corresponded to a yolk sac tumor, and the latter corresponded to a dysgerminoma containing remnants of gonadoblastoma. Based on these cases, the presence of tumor nest multiplicity and central blood vessels might aid the diagnosis of dysgerminoma, and these imaging findings might be indicative of the synchronous development of multiple dysgerminomas from primordial germ cells or gonadoblastomas.

Intravascular gas within an ovarian tumor: a CT sign of ovarian torsion.

A case of twisted ovarian tumor with intravascular gas is presented, and the mechanism of the gas formation is discussed. On the basis of the probable mechanism of gas formation observed in dead fetuses, the gas seen in the present case is considered to have been oxygen released from trapped oxyhemoglobin within the tumor vessels. "Intravascular gas" within an ovarian tumor, although extremely rare, is diagnostic of ovarian torsion.

Prognostic indicators for failure of surveillance management of stage I non-seminomatous germ cell tumours.

Fifty-three patients presenting with non-seminomatous germ cell tumours (NSGCT) of the testis were examined. Particular interest was directed towards the association of several morphological features of the primary tumour with metastatic disease, either at presentation or later in the course of the tumour. It is apparent from this study that the presence of vascular invasion in the primary tumour, high T stage (advanced local disease) and the presence of choriocarcinoma are poor prognostic signs in NSGCT. In such tumours presenting as clinical stage I, surveillance management may not be appropriate because of the high rate of relapse.

Vascularization of malignant testicular tumors.

Recent studies of malignant testicular tumors report a correlation between vascularization, biologic behavior, radiosensitivity, and chemotherapeutic response of the tumor. Postoperative angiographies of malignant testicular tumor specimens (seminoma n = 4, nonseminoma n = 12) showed the following results: Contrary to the symmetric vascularity pattern of normal testes, seminomas were hypovascular, well-defined from normal testicular tissue and not neovascular. Nonseminomas showed isovascularity (n = 5) or hypovascularity (n = 7) but with focal hypervascular areas in the tumor (n = 10), and pathologic neovascularization. Present angiographic studies reveal marked differences in the vasculature pattern of malignant testicular tumors. In nonseminomas, focal hypervascular or neovascular areas as centers of a high-growth rate correlate well with comparable cell kinetic studies. Assuming a similar growth behavior in metastases, the vascularization type of these growth centers theoretically favors the efficient use of chemotherapeutic agents.

Analysis of proliferative compartments in human tumors. II. Seminoma.

Growth pattern and cell kinetics of 12 human seminomas were determined by means of vascular organ perfusion after orchiectomy. The arteria testicularis of the tumor-bearing testis was perfused up to 5 hours with dextran-diluted blood under normothermic and normotonic, simulated physiologic conditions. At defined periods, the specimen was exposed to tritiated and/or carbon 14-labeled thymidine. Autoradiograms prepared of whole tumor sections revealed a dependence of growth pattern on the stage of development. A homogeneous distribution of DNA synthesizing seminoma cells was found in small tumor foci. With increasing size, the zone of proliferation shifted to the periphery of the nodule giving rise to nodular subpopulations of high proliferative activity. In nodules of a diameter of more than about 2 cm the growth compartment consists of a highly proliferating invading cell layer at the edge of the tumor and intratumoral patches of proliferating cells near the vascular stroma. The largest part of the tumor remains at this stage in a quiescent state (G0). The mean labeling index of the seminoma cells was 11.6 +/- 1.4%, with the highest values found immediately adjacent to tumor vessels. High mitotic activity in an anaplastic seminoma was coupled with maximum labeling indices up to 41.9%. DNA synthesis time ts was 15.9 +/- 2.0 hours. The potential population doubling time for the proliferating fraction was in the range of 5 days. Lymphocytic infiltration reduced the proliferative activity in some parts, but was without effect in other areas of the seminoma. The seminoma is an example of a malignant human tumor with a rather regular growth pattern: The distribution of the proliferating compartment appears less dependent on cytologic or histologic structure, but more on tumor geometry and size.

Identification of vessels by lectin-immunoperoxidase staining of endothelium: possible applications in urogenital malignancies.

Ulex europaeus agglutinin I binds specifically to vascular endothelium of various human tissues irrespective of the blood group type or secretive status of the tissue. Using this property, we have developed an immunoperoxidase technique to identify vessel structures in urogenital tissues. Most vessels in malignant and nonmalignant tissues of bladder, prostate and testis of different blood types (A, B, AB and O) can be readily identified by this method. This technique has potential application in detecting tumor cell invasion of vessels and in studying distribution of vessels in relation to various normal and pathological events.

[Angiographic and morphological findings in testis tumors (author's transl)]. / Angiographische und morphologische Befunde bei Hodentumoren.

The arterial supply of testicular tumors is compared to that of normal testes. Data were collected from comparative angiographic and morphologic studies of 21 surgical and autopsy specimens. The arterial vascularization of seminomas is rather poorly developed, newly formed vessels show only minor differences of caliber. Non-seminomatous testicular tumors show a strongly irregular pattern of arterial branching with bends, variations of caliber, irregular contours, completely avascular areas, and extravasation of contrast medium. Depending on the size of tumors, the original testicular arteries are displaced and compressed more or less strongly. Angiographic findings are correlated with morphologic finding. The relevance of different patterns of vascularization for therapeutic considerations is discussed.

Lymphovenous shunting in a case of retroperitoneal seminoma.

Lymphovenous shunting in a patient presenting with a metastatic retroperitoneal seminoma is reported. Its aetiology as well as the prognostic value are discussed. A search of the literature has been made and the various theories offered to explain such a phenomonen have been evaluated, in an attempt to corelate them with the findings in our case.

Vascular structures in brain tumors.

The blood vessels within brain tumors show alterations from the normal anatomy. Some of these seem to be related to an increased capacity to transfer materials between the lumen and the parenchyma and are probably intimately connected with the edema associated with the tumor. These alterations include fenestration, widened intercellular junctions, increase in pinocytotic vesicles, and infolding of the luminal surface. Other alterations are observed but their function is not as clear. The latter include an increase in the number of tubular bodies, the appearance of tubular structures within vacuoles, tubular arrays within the nuclear envelope and rough endoplasmic reticulum, and endothelial proliferation, among others.