Preoperative giant sacrococcygeal teratoma embolization in a newborn - A case report and a review

Sacrococcygeal teratoma (SCT) is the most frequent congenital germ cell tumor. Patients have a higher risk of perinatal complications and death, with bleeding and cardiac decompensation being the most common causes of neonatal mortality. This is the case of a 35-week preterm newborn with a large SCT diagnosed at ultrasound screening in the second trimester. Preoperative selective embolization of the middle sacral artery and total surgical resection were performed postnatally with minimal blood loss. The patient was discharged at 25 days of life with a normal physical examination. Selective embolization prior to giant SCT resection is feasible and appears as a safe and useful technique in the control of perioperative bleeding.

Perlecan maintains microvessel integrity in vivo and modulates their formation in vitro

Perlecan is a heparan sulfate proteoglycan assembled into the vascular basement membranes (BMs) during vasculogenesis. In the present study we have investigated vessel formation in mice, teratomas and embryoid bodies (EBs) in the absence of perlecan. We found that perlecan was dispensable for blood vessel formation and maturation until embryonic day (E) 12.5. At later stages of development 40% of mutant embryos showed dilated microvessels in brain and skin, which ruptured and led to severe bleedings. Surprisingly, teratomas derived from perlecan-null ES cells showed efficient contribution of perlecan-deficient endothelial cells to an apparently normal tumor vasculature. However, in perlecan-deficient EBs the area occupied by an endothelial network and the number of vessel branches were significantly diminished. Addition of FGF-2 but not VEGF(165) rescued the in vitro deficiency of the mutant ES cells. Furthermore, in the absence of perlecan in the EB matrix lower levels of FGFs are bound, stored and available for cell surface presentation. Altogether these findings suggest that perlecan supports the maintenance of brain and skin subendothelial BMs and promotes vasculo- and angiogenesis by modulating FGF-2 function.

High expression of NPY receptors in the human testis

NPY receptors represent novel molecular therapeutic targets in cancer and obesity. However, the extent of NPY receptor expression in normal human tissues is poorly investigated. Based on the role of NPY in reproductive functions, the NPY receptor expression was studied in 25 normal human testes and, additionally, 24 testicular tumors using NPY receptor autoradiography. In the normal testis, Leydig cells strongly expressed NPY receptor subtype Y2, and small arterial blood vessels Y1. Y2 receptors were found to be functional with agonist-stimulated [(35)S]GTPγS binding autoradiography. Full functional integrity of the NPY system was further suggested by the immunohistochemical detection of NPY peptide in nerve fibers directly adjacent to Leydig cells and arteries. Germ cell tumors expressed Y1 and Y2 on tumor cells in 33% and Y1 on intratumoral blood vessels in 50%. Based on its strong NPY receptor expression in Leydig cells and blood vessels, the normal human testis represents a potentially important physiological and pharmalogical NPY target.

Three-dimensional power Doppler sonography in the diagnosis of a cystic sacrococcygeal teratoma mimicking a meningomyelocele: A case report

Sacrococcygeal teratomas have been diagnosed prenatally on sonograms as masses of cystic, solid, or mixed echogenicity from the sacral area and protruding through the perineum or buttocks. However, a cystic sacrococcygeal teratoma may be misdiagnosed as an anterior sacral meningomyelocele, especially when presenting as a posterior cystic mass. We report a case in which three-dimensional power Doppler imaging was helpful for making a correct prenatal diagnosis of a type 1 cystic sacrococcygeal teratoma, which mimicked a meningomyelocele.

Contribution of host-derived tissue factor to tumor neovascularization

OBJECTIVE

The role of host-derived tissue factor (TF) in tumor growth, angiogenesis, and metastasis has hitherto been unclear and was investigated in this study.

METHODS AND RESULTS

We compared tumor growth, vascularity, and responses to cyclophosphamide (CTX) of tumors in wild-type (wt) mice, or in animals with TF levels reduced by 99% (low-TF mice). Global growth rate of 3 different types of transplantable tumors (LLC, B16F1, and ES teratoma) or metastasis were unchanged in low-TF mice. However, several unexpected tumor/context-specific alterations were observed in these mice, including: (1) reduced tumor blood vessel size in B16F1 tumors; (2) larger spleen size and greater tolerance to CTX toxicity in the LLC model; (3) aborted tumor growth after inoculation of TF-deficient tumor cells (ES TF(-/-)) in low-TF mice. TF-deficient tumor cells grew readily in mice with normal TF levels and attracted exclusively host-related blood vessels (without vasculogenic mimicry). We postulate that this complementarity may result from tumor-vascular transfer of TF-containing microvesicles, as we observed such transfer using human cancer cells (A431) and mouse endothelial cells, both in vitro and in vivo.

CONCLUSIONS

Our study points to an important but context-dependent role of host TF in tumor formation, angiogenesis and therapy.

Upper abdominal teratomas in infants: radiological findings and importance of the vascular anatomy

BACKGROUND

Primary upper abdominal teratomas are extremely rare tumours, most commonly arising in infants. The radiological literature relating to them is sparse. Surgical resection is difficult due to distortion of the vascular anatomy.

OBJECTIVE

To reassess the value of preoperative imaging with specific reference to the presence/absence of typical features of teratoma, anatomical location and adjacent vascular anatomy.

MATERIALS AND METHODS

The histopathology database was used to identify infants with upper abdominal teratoma. Pathological, surgical and radiological data were reviewed.

RESULTS

The search of the database identified 12 infants (10 girls, 2 boys) with an abdominal/retroperitoneal teratoma during the period 1993 to 2006. All teratomas were benign. In the majority of infants, typical radiological features of teratoma were demonstrated (fat, calcium). Identification of the major abdominal vessels on CT scan (most commonly the inferior vena cava) was not possible in all infants. Distortion (and commonly encasement) of the adjacent major abdominal vessels was usually evident.

CONCLUSION

Upper abdominal teratomas in infants have typical radiological features. Preoperative delineation of the major vascular anatomy is often imprecise. Significant distortion of vascular anatomy was present in all infants and awareness of this feature impacts on surgical planning.

Platelet-Derived Growth Factor Receptor-β Constitutive Activity Promotes Angiogenesis In Vivo and In Vitro

OBJECTIVE

Knockout studies have demonstrated crucial roles for the platelet-derived growth factor-B and its cognate receptor, platelet-derived growth factor receptor-beta (PDGFR-beta), in blood vessel maturation, that is, the coverage of newly formed vessels with mural cells/pericytes. This study describes the consequences of a constitutively activating mutation of the PDGFR-beta (Pdgfrb(D849V)) introduced into embryonic stem cells with respect to vasculogenesis/angiogenesis in vitro and in vivo.

METHODS AND RESULTS

Embryonic stem cells were induced to either form teratomas in vivo or embryoid bodies, an in vitro model for mouse embryogenesis. Western blotting studies on embryoid bodies showed that expression of a single allele of the mutant Pdgfrb led to increased levels of PDGFR-beta tyrosine phosphorylation and augmented downstream signal transduction. This was accompanied by enhanced vascular development, followed by exaggerated angiogenic sprouting with abundant pericyte coating as shown by immunohistochemistry/immunofluorescence. Pdgfrb(D849V/+) embryoid bodies were characterized by increased expression of vascular endothelial growth factor (VEGF)-A and VEGF receptor-2; neutralizing antibodies against VEGF-A/VEGF receptor-2 blocked vasculogenesis and angiogenesis in mutant embryoid bodies. Moreover, Pdgfrb(D849V/+) embryonic stem cell-derived teratomas in nude mice were more densely vascularized than wild-type teratomas.

CONCLUSIONS

Increased PDGFR-beta kinase activity is associated with elevated expression of VEGF-A and VEGF receptor-2, acting directly on endothelial cells and resulting in increased vessel formation.

The influence of a human embryonic stem cell-derived microenvironment on targeting of human solid tumor xenografts

The awareness of the important role that the surrounding tissue microenvironment and stromal response play in the process of tumorigenesis has grown as a result of in vivo models of tumor xenograft growth in immunocompromised mice. In the current study, we used human embryonic stem cells in order to study the interactions of tumor cells with the surrounding microenvironment of differentiated human cell tissues and structures. Several cancer cell types stably expressing an H2A-green fluorescence protein fusion protein, which allowed tracking of tumor cells, were injected into mature teratomas and developed into tumors. The salient findings were: (a) the observation of growth of tumor cells with high proliferative capacity within the differentiated microenvironment of the teratoma, (b) the identification of invasion by tumor cells into surrounding differentiated teratoma structures, and (c) the identification of blood vessels of human teratoma origin, growing adjacent to and within the cancer cell-derived tumor. Mouse embryonic stem cell-derived teratomas also supported cancer cell growth, but provided a less suitable model for human tumorigenesis studies. Anticancer immunotherapy treatment directed against A431 epidermoid carcinoma cell-related epitopes induced the complete regression of A431-derived tumor xenografts following direct i.m. injection in immunocompromised mice, as opposed to corresponding tumors growing within a human embryonic stem cell-derived microenvironment, wherein remnant foci of viable tumor cells were detected and resulted in tumor recurrence. We propose using this novel experimental model as a preclinical platform for investigating and manipulating the stromal response in tumor cell growth as an additional tool in cancer research.

TIMP-3 deficiency in the host, but not in the tumor, enhances tumor growth and angiogenesis

Tumor cells, stromal cell compartment and the extracellular matrix (ECM) together generate a multifaceted tumor microenvironment. Matrix metalloproteinases and their tissue inhibitors (TIMPs) provide a means for tumor-stromal interaction during tumorigenesis. Among TIMPs, TIMP-3 is uniquely localized to the ECM and is frequently silenced in human cancers. Here, we asked whether the absence of TIMP-3 in the tumor cell or the host affects the process of tumorigenesis. Timp-3(-/-) ES-cell clones were generated and used to develop teratomas in nude mice. Timp-3(-/-) teratomas showed similar tumor take, growth, and angiogenesis compared to timp-3(+/+) teratomas. To study the effect of TIMP-3 ablation in the host stroma, we measured the growth kinetics of subcutaneous B16F10 melanomas in timp-3(-/-) and wild-type littermates. Tumors grew significantly faster in timp-3(-/-) than in wild-type mice and their CD31 content was significantly higher indicating increased angiogenesis. Augmented angiogenesis in timp-3(-/-) mice was directly tested using Matrigel plug and Gelfoam assays. In response to FGF-2, timp-3(-/-) endothelial cells invaded more efficiently, leading to enhanced formation of functional blood vessels. Thus, TIMP-3 deficiency in the host, but not in the tumor per se, leads to enhanced tumor growth and angiogenesis. TIMP-3 located within the tumor microenvironment inhibits tumorigenesis.

Three-dimensional power Doppler (3DPD) ultrasound in the diagnosis and follow-up of fetal vascular anomalies

OBJECTIVE

This study was undertaken to examine the value of 3-dimensional power Doppler (3DPD) ultrasound imaging in diagnosis and follow-up of fetal vascular anomalies.

STUDY DESIGN

In 174 women undergoing early second-trimester targeted organ scanning, followed by a midtrimester second scan in a university hospital setting, 3DPD was applied to the fetal intra-abdominal and intrathoracic vessels.

RESULTS

In 137 of 174 fetuses (75%) in the earlier scan, and in 164 of 174 fetuses (95%) in the later scan, 3DPD ultrasound successfully visualized the fetal vessels. In an additional 9 cases, anomalous vascularity was identified: fetal intra-abdominal umbilical vein varix (2), persistent right umbilical vein (1), agenesis of ductus venosus (2), eventration of diaphragm (1), parenchymal and vascular lung anomaly (1), sacrococcygeal teratoma (1), and chorioangioma (1). 3DPD improved diagnostic precision, aided our understanding of anomalous structure, and added information on the vascular volume of lesions in some cases.

CONCLUSION

3DPD improved ultrasound visualization of the fetal vessels of the abdomen and thorax in normal and anomalous cases.

Abdominal pain in a patient with osteosarcoma

Abdominal pain often occurs in patients receiving chemotherapy. The authors describe a patient with osteosarcoma who developed severe right-sided abdominal discomfort several days after being admitted for fever, neutropenia, and mucositis. Unexpectedly, the patient's pain was not therapy-related, but rather was caused by a midline pelvic mass.

Fibroblast Growth Factor Receptor-1 Expression Is Required for Hematopoietic but not Endothelial Cell Development

OBJECTIVE

The purpose of this study was to clarify the role of fibroblast growth factors (FGFs) and FGF receptors (FGFRs) in hematopoietic/endothelial development.

METHODS AND RESULTS

Using several different FGFR-1-specific antibodies and FGFR-1 promoter-driven LacZ activity, we show that FGFR-1 is expressed and active as a tyrosine kinase in a subpopulation of endothelial cells (approximately 20% of the endothelial pool) during development in embryoid bodies. In agreement, in stem cell-derived teratomas, expression of FGFR-1 was detected in some but not all vessels. The FGFR-1 expressing endothelial cells were mitogenically active in the absence and presence of vascular endothelial growth factor (VEGF). Expression of FGFR-1 in endothelial cell precursors was not required for vascular development, and vascularization was enhanced in FGFR-1-deficient embryoid bodies compared with wild-type stem cells. In contrast, hematopoietic development was severely disturbed, with reduced expression of markers for primitive and definitive hematopoiesis.

CONCLUSIONS

Our data show that FGFR-1 is expressed in early hematopoietic/endothelial precursor cells, as well as in a subpool of endothelial cells in tumor vessels, and that it is critical for hematopoietic but not for vascular development.

Targeted replacement of hypoxia-inducible factor-1alpha by a hypoxia-inducible factor-2alpha knock-in allele promotes tumor growth

Hypoxia-inducible factors (HIF) are essential transcriptional regulators that mediate adaptation to hypoxic stress in rapidly growing tissues such as tumors. HIF activity is regulated by hypoxic stabilization of the related HIF-1alpha and HIF-2alpha subunits, which are frequently overexpressed in cancer cells. To assess the relative tumor-promoting functions of HIF-1alpha and HIF-2alpha directly, we replaced HIF-1alpha expression with HIF-2alpha by creating a novel "knock-in" allele at the Hif-1alpha locus through homologous recombination in primary murine embryonic stem cells. Compared with controls, s.c. teratomas derived from knock-in embryonic stem cells were larger and more proliferative, had increased microvessel density, and exhibited increased expression of vascular endothelial growth factor, transforming growth factor-alpha, and cyclin D1. These and other data indicate that HIF-2alpha promotes tumor growth more effectively than HIF-1alpha in multiple contexts.

Vascular Development in Early Human Embryos and in Teratomas Derived from Human Embryonic Stem Cells1

During early human embryonic development, blood vessels are stimulated to grow, branch, and invade developing tissues and organs. Pluripotent human embryonic stem cells (hESCs) are endowed with the capacity to differentiate into cells of blood and lymphatic vessels. The present study aimed to follow vasculogenesis during the early stages of developing human vasculature and to examine whether human neovasculogenesis within teratomas generated in SCID mice from hESCs follows a similar course and can be used as a model for the development of human vasculature. Markers and gene profiling of smooth muscle cells and endothelial cells of blood and lymphatic vessels were used to follow neovasculogenesis and lymphangiogenesis in early developing human embryos (4-8 weeks) and in teratomas generated from hESCs. The involvement of vascular smooth muscle cells in the early stages of developing human embryonic blood vessels is demonstrated, as well as the remodeling kinetics of the developing human embryonic blood and lymphatic vasculature. In teratomas, human vascular cells were demonstrated to be associated with developing blood vessels. Processes of intensive remodeling of blood vessels during the early stages of human development are indicated by the upregulation of angiogenic factors and specific structural proteins. At the same time, evidence for lymphatic sprouting and moderate activation of lymphangiogenesis is demonstrated during these developmental stages. In the teratomas induced by hESCs, human angiogenesis and lymphangiogenesis are relatively insignificant. The main source of blood vessels developing within the teratomas is provided by the murine host. We conclude that the teratoma model has only limited value as a model to study human neovasculogenesis and that other in vitro methods for spontaneous and guided differentiation of hESCs may prove more useful.

In vitroandIn vivoModels Analyzing von Hippel-Lindau Disease-Specific Mutations

Mutations in the von Hippel-Lindau (VHL) tumor suppressor gene cause tissue-specific tumors, with a striking genotype-phenotype correlation. Loss of VHL expression predisposes to hemangioblastoma and clear cell renal cell carcinoma, whereas specific point mutations predispose to pheochromocytoma, polycythemia, or combinations of hemangioblastoma, renal cell carcinoma, and/or pheochromocytoma. The VHL protein (pVHL) has been implicated in many cellular activities including the hypoxia response, cell cycle arrest, apoptosis, and extracellular matrix remodeling. We have expressed missense pVHL mutations in Vhl(-/-) murine embryonic stem cells to test genotype-phenotype correlations in euploid cells. We first examined the ability of mutant pVHL to direct degradation of the hypoxia inducible factor (HIF) subunits HIF1alpha and HIF2alpha. All mutant pVHL proteins restored proper hypoxic regulation of HIF1alpha, although one VHL mutation (VHL(R167Q)) displayed impaired binding to Elongin C. This mutation also failed to restore HIF2alpha regulation. In separate assays, these embryonic stem cells were used to generate teratomas in immunocompromised mice, allowing independent assessment of the effects of specific VHL mutations on tumor growth. Surprisingly, teratomas expressing the VHL(Y112H) mutant protein displayed a growth disadvantage, despite restoring HIFalpha regulation. Finally, we observed increased microvessel density in teratomas derived from Vhl(-/-) as well as VHL(Y112H), VHL(R167Q), and VHL(R200W) embryonic stem cells. Together, these observations support the hypothesis that pVHL plays multiple roles in the cell, and that these activities can be separated via discrete VHL point mutations. The ability to dissect specific VHL functions with missense mutations in a euploid model offers a novel opportunity to elucidate the activities of VHL as a tumor suppressor.

Giant, highly vascular sacrococcygeal teratoma: report of its excision using the ligasure vessel sealing system

Reports about giant, highly vascular sacrococcygeal teratoma (GHV-SCT) are uncommon. A boy with a prenatally diagnosed GHV-SCT was born at 34 weeks' gestation weighing 3,716 g. At birth, the GHV-SCT was 20 x 17 x 14 cm. After initial devascularization using an aortic snare, excision of the GHV-SCT was started using monopolar diathermy, but hemorrhage from cutaneous collateral vessels was difficult to control, and individual ligation of vessels was extremely time consuming. The authors then used the LigaSure (LS) vessel sealing system (Valleylab, Boulder, CO) to control intraoperative hemorrhage. Hemostasis was achieved easily with LS, without any need for vessel ligation; the operative field was dry and the efficiency of excision enhanced. Total operating time was 255 minutes, but excision of the GHV-SCT itself took only 16 minutes. The GHV-SCT weighed 1,208 g or 325.1 g/kg body weight. Total blood loss was 77 mL or 20.7 mL/kg body weight, which was minimal compared with other cases in the literature. At the last follow-up examination, 7 months after surgery, he remains well with no evidence of recurrence. LS was extremely useful for controlling intraoperative hemorrhage in this case, and we strongly recommend its selective use for excising highly vascular SCT.

Laparoscopic ligation of the median sacral artery before resection of a sacrococcygeal teratoma

To minimize the risk of exsanguinating hemorrhage, the authors describe a technique of laparoscopic ligation of the median sacral artery before posterior sagittal resection of type I sacrococcygeal teratoma (SCT). Two female infants with antenatally diagnosed SCT underwent postnatal evaluation and preoperative imaging and were taken to the operating room. In both patients, pneumoperitoneum was established via an epigastic 5-mm trocar. Two additional trocars were inserted in the right and left lower quadrants. The peritoneal reflection was opened to the right of the sigmoid colon, and the presacral space was explored. A large median sacral artery was identified easily, isolated, and divided. The children then were placed in a prone position, and the tumors underwent en bloc resection via a Chevron incision with minimal blood loss. The laparoscopic portion of the procedure was performed in an average of 15 minutes. This is the first report of laparoscopic ligation of the median sacral artery before posterior resection of a sacrococcygeal tumor in an infant. This technique can be performed easily with minimal morbidity. Division of this artery is a logical preventative measure and may reduce the risk of hemorrhage during operative resection.

Embryonic Cell Lines with Endothelial Potential: An In Vitro System for Studying Endothelial Differentiation

Objective— Endothelial differentiation is a fundamental process in angiogenesis and vasculogenesis with implications in development, normal physiology, and pathology. To better understand this process, an in vitro cellular system that recapitulates endothelial differentiation and is amenable to experimental manipulations is required.

Methods and Results— Embryonic cell lines that differentiate exclusively into endothelial cells were derived from early mouse embryos using empirical but reproducible culture techniques without viral or chemical transformation. The cells were not pluripotent and expressed reduced levels of Oct 4 and Rex-1 . They were non-tumorigenic with a population doubling time of ≈15 hours. When plated on matrigel, they readily differentiated to form patent tubular structures with diameters of 30 to 150 μm. The differentiated cells endocytosed acetylated low-density lipoprotein (LDL) and began to express endothelial-specific markers such as CD34, CD31, Flk-1, TIE2, P-selectin, Sca-1, and thy-1. They also expressed genes essential for differentiation and maintenance of endothelial lineages, eg, Flk-1, vascular endothelial growth factor (VEGF), and angiopoietin-1. When transplanted into animal models, these cells incorporated into host vasculature.

Conclusions— These cell lines can undergo in vitro and in vivo endothelial differentiation that recapitulated known endothelial differentiation pathways. Therefore, they are ideal for establishing an in vitro cellular system to study endothelial differentiation.

The laparoscopic approach to sacrococcygeal teratomas

BACKGROUND

Sacrococcygeal teratomas (SCT) are classically approached posteriorly through an inverted chevron incision. In large, external, mainly solid SCT, prior interruption of the arterial supply is warranted because of impending heart failure and life-threatening hemorrhagic diathesis. Hitherto, this has required prior laparotomy. A laparotomy is also added when the tumor extends presacrally into the pelvis. The presacral region is, however, difficult to access. A laparoscopic-assisted approach seems to offer a solution for both problems.

METHODS

A laparoscopic-assisted approach was used in five patients with SCT. In one neonate, it was used to interrupt the arterial blood supply only; in the other four patients, it was used to dissect the internal extension of the tumor.

RESULTS

Laparoscopic interruption of the median sacral artery proved to be simple in the neonate with a large, external, mainly solid SCT. In three of the remaining four patients with presacral extension of the tumor, good visualization and dissection of the intrapelvic portion of the tumor was obtained. In one patient, the procedure had to be converted because of a lack of working space due to extensive intraabdominal growth of the tumor.

CONCLUSION

A laparoscopic-assisted approach seems to be ideal for SCT. It provides the opportunity to interrupt the median sacral artery before the dissection. Moreover, it enables far better access to the presacral area than the conventional surgical approach when the SCT extends presacrally into the pelvis. Such a meticulous laparoscopic dissection may improve the functional results.

Contrasting effects of VEGF gene disruption in embryonic stem cell-derived versus oncogene-induced tumors

Previous gene targeting studies have implicated an indispensable role of vascular endothelial growth factor (VEGF) in tumor angiogenesis, particularly in tumors of embryonal or endocrine origin. In contrast, we report here that transformation of VEGF-deficient adult fibroblasts (MDF528) with ras or neu oncogenes gives rise to highly tumorigenic and angiogenic fibrosarcomas. These aggressive VEGF-null tumors (528ras, 528neu) originated from VEGF(-/-) embryonic stem cells, which themselves were tumorigenically deficient. We also report that VEGF production by tumor stroma has a modest role in oncogene-driven tumor angiogenesis. Both ras and neu oncogenes down-regulated at least two endogenous inhibitors of angiogenesis [pigment epithelium derived factor (PEDF) and thrombospondin 1 (TSP-1)]. This is functionally important as administration of an antiangiogenic TSP-1 peptide (ABT-526) markedly inhibited growth of VEGF(-/-) tumors, with some ingress of pericytes. These results provide the first definitive genetic demonstration of the dispensability of tumor cell-derived VEGF in certain cases of 'adult' tumor angiogenesis, and thus highlight the importance of considering VEGF-independent as well as VEGF-dependent pathways when attempting to block this process pharmacologically.

Ovarian teratomas with florid benign vascular proliferation: a distinctive finding associated with the neural component of teratomas that may be confused with a vascular neoplasm

Prominent benign vascular proliferations associated with neural tissue in five cases of ovarian teratoma are described. The ages of the patients ranged from 15 to 35 years. Three of the five had tumors confined to the ovary, one had peritoneal implants, and one had widespread metastatic immature teratoma. Two of the patients are alive and well, 8 and 9 years postoperatively. Follow-up is unavailable in two cases and the final case was recent. The tumor in three of the cases had features of mature cystic teratoma including abundant mature neural tissue and, in one instance, microscopic foci of primitive neuroepithelium. The tumor in the fourth case was an immature teratoma with abundant primitive neuroepithelium, and in the fifth case was a mixed germ cell tumor, composed mostly of immature teratoma with a minor component of yolk sac tumor. In all the tumors there was a prominent vascular proliferation composed of long thin-walled, curved vessels or a solid glomeruloid arrangement. Immunohistochemistry done in two cases confirmed the vascular nature of the proliferation. Angiogenesis, likely as an expression of vascular endothelial growth factors, is a well-known phenomenon in a variety of neural and neuroendocrine neoplasms, in particular high-grade gliomas. However, very few cases of this phenomenon have been described in association with neural tissue in the ovary. Recognition of this proliferation as a benign secondary one is important to avoid misdiagnosis of a vascular neoplasm or an immature teratoma, as happened in one of our cases.

Systemic-pulmonary shunting and hemoptysis in a benign intrathoracic teratoma

Hemoptysis as a presenting symptom in benign intrathoracic teratoma is rare, but we have documented one such case and discuss the various possibilities of why such a problem should arise. The bleeding was secondary to systemic-pulmonary artery shunting, caused at least in part by extensive pleural adhesions. The exact cause of the adhesions was not determined but possibilities include previous infection or trauma. The tumor was successfully removed surgically.

Radiofrequency ablation of human fetal sacrococcygeal teratoma

OBJECTIVE

Fetuses with solid, highly vascularized sacrococcygeal teratomas can die as a result of the vascular steal syndrome. This is the first report in which a percutaneous technique, radiofrequency ablation, was used to interrupt blood flow to a sacrococcygeal teratoma in 4 human fetuses.

STUDY DESIGN

A radiofrequency ablation probe was percutaneously inserted into the fetal tumor under ultrasonographic guidance. In 2 fetuses a significant portion of the tumor mass was ablated, whereas in the other 2 fetuses only the major feeding vessels were targeted.

RESULTS

Two infants were delivered at 28 and 31 weeks' gestation, respectively, and are doing well. In 2 other cases hemorrhage into the tumor led to an unfavorable fetal outcome.

CONCLUSION

Ablation of a majority of the tumor tissue in sacrococcygeal teratoma is not necessary and proved fatal in two instances. Targeted ablation of the feeding tumor vessels diminishes blood flow sufficiently to reverse high-output fetal heart failure.

Transvaginal color Doppler ultrasonic characterization of benign and malignant ovarian cystic teratomas and comparison with serum squamous cell carcinoma antigen

BACKGROUND

The preoperative diagnosis of squamous cell carcinoma (SCC) arising in mature cystic teratoma of the ovary remains difficult. The purpose of this study is to examine the usefulness of transvaginal color Doppler ultrasound (TV-CDU) in differentiating malignant (SCC) from benign cystic teratoma of the ovary.

METHODS

Eighty-eight patients with an ovarian tumor showing gray scale sonographic appearances of mature cystic teratoma were preoperatively evaluated for the presence or absence of intratumoral blood flow by TV-CDU. The blood flow characteristics of the tumor vessels were analyzed using the resistance index (RI), pulsatility index (PI), and peak systolic velocity (PSV). The serum levels of SCC antigen were also randomly examined preoperatively in 50 patients.

RESULTS

Intratumoral blood flow was significantly detected in malignant teratomas (SCCs) (80.0%; 4 of 5) compared with benign teratomas (20.5%; 17 of 83) (P < 0.01). All malignant teratomas with intratumoral blood flow showed both RI less than 0.4 and PI less than 0.6, whereas no benign teratomas showed any such value except for 1 case with struma ovarii. In addition, both the mean RI and the mean PI values in the tumor vessels were significantly lower in the malignant teratomas (RI: 0.31 +/- 0.07; PI: 0.40 +/- 0.16) than in the benign teratomas (RI: 0.62 +/- 0.13; PI: 1.06 +/- 0.44) (P < 0.001). However, the mean PSV value of the malignant teratomas (PSV: 20.6 +/- 8.33) was not significantly different from the benign teratomas (PSV: 18.1 +/- 9.9). Elevation of serum SCC was found in 4 of 5 patients (80%) with malignant teratomas, whereas the elevation was found in 11 of 45 patients (24.4%) with benign teratomas (P < 0.05). The diagnostic accuracy using the RI (cutoff value 0.4) as well as the PI (cutoff value 0.6) was thus 95.2%, which was significantly superior to that obtained by using the serum SCC (76%) (cutoff value, 1.5 ng/mL).

CONCLUSIONS

Evaluating the presence or absence of intratumoral blood flow, together with blood flow resistance, in tumor vessels using TV-CDU thus may be more useful to differentiate malignant (SCC) from benign cystic teratomas of the ovary than by measuring serum SCC levels.

Sonographic prognostic factors in fetuses with sacrococcygeal teratoma

BACKGROUND

A subset of fetuses with sacrococcygeal teratoma (SCT) develops hydrops caused by high-output heart failure. Identification of fetuses at risk for hydrops is important because fetal intervention may reverse the pathophysiology of the disease. To date, no reliable sonographic prognostic factors have been identified.

METHODS

An experienced sonologist reviewed the sonographic records of 17 fetuses with SCT referred to the authors' institution. Size of the tumor was measured and corrected for fetal size. The appearance of the tumor (solid versus cystic) and its vascularity were graded on a subjective scale of 1 to 5.

RESULTS

Only 4 of 12 fetuses that had hydrops survived; of the survivors, 3 had undergone fetal intervention. All nonhydropic fetuses survived. Fetuses with hydrops had tumors that were mainly solid and highly vascular, whereas nonhydropic fetuses had predominantly cystic tumors with comparatively less vascularity. There was no significant difference in tumor size between these 2 groups.

CONCLUSIONS

Fetuses with SCT that are mainly solid in appearance and are highly vascularized have a higher risk of getting hydrops in utero. Tumor size is not an independent prognostic factor.

Spinal cord vascular disease: characterization with fast three-dimensional contrast-enhanced MR angiography

BACKGROUND AND PURPOSE

Noninvasive characterization of spinal vascular lesions is essential for guiding clinical management, and several MR angiographic techniques have been applied in the past with variable results. The purpose of our study was to assess the potential of a dynamic 3D contrast-enhanced MR angiographic sequence to characterize spinal vascular lesions and to identify their arterial feeders and venous drainage.

METHODS

A contrast-enhanced gradient-echo 3D pulse sequence providing angiographic information within 24 seconds was applied prospectively in 12 consecutive patients with a presumed spinal vascular lesion. The images were evaluated for visibility of the arterial feeder, and the results were compared with those of conventional angiography performed the next day.

RESULTS

The MR angiographic findings proved that the lesions were correctly characterized as spinal arteriovenous malformations (AVMs) (n = 6), spinal dural arteriovenous fistulas (AVFs) (n = 3), a hemangioblastoma (n = 1), a teratoma (n = 1), and a vertebral hemangioma (n = 1). The arterial feeder was visible in all six AVMs and in the hemangioblastoma, corresponding to conventional angiographic findings. In two of three spinal dural AVFs, an enlarged draining medullary vein was seen within the neural foramen, providing correct localization. The third fistula could not be seen owing to reduced image quality from motion artifacts.

CONCLUSION

Fast 3D contrast-enhanced MR angiography is a noninvasive technique with high accuracy in the characterization of spinal vascular disease. Visibility of the arterial pedicles corresponds well with that of digital subtraction angiography, facilitating the management of these patients.

CT features of torsion of benign cystic teratoma of the ovary

PURPOSE

The purpose of this work was to evaluate the usefulness of CT scans for distinguishing torsed from uncomplicated benign cystic teratoma (BCT).

METHOD

Retrospective analysis was performed in 14 torsed BCTs (14 patients) and in 23 uncomplicated BCTs (20 patients) for comparison. The features on CT scans were compared to the pathologic findings.

RESULTS

CT findings indicating torsed BCT were the presence of eccentric wall thickening of >1 cm, peritumoral infiltration, and presence of enlarged solid tubal mass adjacent to the uterus (p < 0.05).

CONCLUSION

The present study suggests that CT is useful in differentiating torsed from uncomplicated BCT. Although CT findings are not specific for some patients, detection of certain CT findings could increase the diagnostic accuracy.

Prenatal sonographic imaging of an immature intracranial teratoma

This article describes the prenatal sonographic diagnosis of a rare case of intracranial immature teratoma in a fetus at the 35th week of gestation which looked normal at previous examinations. At sonography a markedly enlarged fetal head containing a complex irregular mass and hydrocephalus was detected. Color Doppler examination of the mass showed intense vascularization with low resistance flows.

Experience with vascular control before excision of giant, highly vascular sacrococcygeal teratomas in neonates

Sacrococcygeal teratomas (SCT) are the most common neoplasms in newborns with a reported occurrence of 1 in 35,000 live births. Highly vascularized tumors in which the ratio of tumor weight to patient weight approaches 1:1 are frequently associated with hyperdynamic states, prenatal hydrops, placentamegaly, postnatal high-output cardiac failure, and carry a high perinatal mortality rate. Operative management of giant, highly-vascular sacrococcygeal teratomas in neonates can be complicated by life-threatening hemorrhage. Laparotomy, control of the aorta, and the arterial blood supply to these tumors before resection has been advocated as a safer alternative. The authors report their experience with three infants successfully treated using this approach. Hemodynamic stability was maintained during the operations. All tumors were resected successfully. The patients are alive without evidence of recurrence, 8.5 months to 18 months (average, 14.3 months) after the operation. Alpha-fetoprotein levels dropped to normal range after the removal of SCT and have remained normal in follow-up. Vascular control before excision of giant, highly-vascular SCT in neonates is safe, decreases intraoperative blood loss, and postoperative morbidity.

Laparoscopic clipping of the median sacral artery in huge sacrococcygeal teratomas

Huge sacrococcygeal teratomas in the newborn can cause significant morbidity and even death due to cardiac failure, hemorrhage, or both. Surgical removal is the treatment of choice, but can indicate these events. Ligation of the median sacral artery, which always supplies the tumor, prior to its removal has been advocated, but in the past this procedure required a formal laparotomy. Nowadays, it can be easily accomplished laparoscopically, as this case report demonstrates.

Vascular density does not predict future metastatic disease in clinical stage 1 non-seminomatous germ cell tumours of the testis

AIM

This study aimed to determine whether patients with stage 1 testicular non seminomatous germ cell tumours (NSGCT) with high vascular density have a greater risk of disease recurrence than those with a low vascular density.

METHODS AND RESULTS

Orchidectomy specimens from 42 patients with stage 1 NSGCT, treated by orchidectomy and surveillance alone, were studied. Vessel density was counted in tumour sections immunohistochemically stained for CD34. The mean of the three highest counts (x250, field size 0.67 mm2) for each tumour was used. Tumour vessel density was very similar for relapsing and non relapsing patients. Vascular invasion was the only variable significantly predictive of disease recurrence at 2 years post-orchidectomy (P = 0.025). There was wide variation of vessel counts between different blocks of a tumour, compared with interobserver variation. The tumour tissue type in the area of highest vessel density was embryonal carcinoma in 50% and teratoma (mature or immature) in 38%.

CONCLUSIONS

We confirmed the value of vascular invasion as a prognostic marker in stage 1 NSGCT. Tumour vessel density was of no prognostic value. Two factors may contribute to this. First, there was wide variation of vessel density between different blocks of a tumour. Second, the most vascular area in a tumour was frequently in low-grade tumour.

Beta 1 integrin is essential for teratoma growth and angiogenesis

Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of beta 1 integrin during teratoma formation, we compared teratomas induced by normal and beta1-null ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, beta 1-null ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of beta 1-null teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in beta1-null teratomas. Basement membranes were present but with irregular shape and detached from the cell surface. Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell-derived endothelial cells. In contrast, beta 1-null teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although beta 1- deficient endothelial cells were absent in teratomas, beta 1-null ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in beta1-null embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in beta 1-null embryoid bodies.

Color Doppler aided prenatal diagnosis of a type 1 cystic sacrococcygeal teratoma simulating a meningomyelocele

Type 1 cystic sacrococcygeal teratomas, usually associated with good outcome following neonatal resection, must be differentiated at the time of prenatal diagnosis from sonographically similar meningomyeloceles, which carry a grave prognosis. We present an unusual case in which color Doppler imaging assisted correct midtrimester prenatal diagnosis of a large type 1 cystic sacrococcygeal teratoma closely simulating a meningomyelocele.

Devascularization and staged resection of giant sacrococcygeal teratoma in the premature infant

Sacrococcygeal teratoma identified in utero is associated with 50% fetal demise, which is caused by hyperdynamic cardiac failure, hemorrhage, and polyhydramnios-induced preterm labor. A premature infant (26 weeks' gestation) with prenatally diagnosed sacrococcygeal teratoma was managed successfully with initial devascularization to control the hyperdynamic state, followed by staged resection.

Highly vascularized sacrococcygeal teratoma: description of this atypical variant and its operative management

The authors report on three infants who had an unusual variant of sacrococcygeal teratoma--a highly vascularized tumor. All three patients had major problems perioperatively, which resulted in cardiac arrest in all three and the death of one. Several suggestions are made concerning diagnosis as well as preoperative and intraoperative management of this rare tumor variant.

Management of fetal sacroccocygeal teratoma

With the advent of antenatal ultrasound, the focus on sacroccocygeal teratoma has shifted from management at birth to management in the antenatal period. Multidisciplinary approach involving the obstetrician, neonatologist and paediatric surgeon is necessary to achieve good results. Two cases of antenatally detected sacrococcygeal teratomas are reported, one at 24 weeks and the other at 26 weeks of gestation. The tumour was benign in both cases and in both cases, delivery was done at full term. In one case, it was a normal vaginal delivery and in the other, an elective lower segment caesarean section was performed. Close ultrasound follow-up during pregnancy had excluded cardiac failure, hydropic changes and other congenital anomalies which could have altered the management of the pregnancy. Accurate diagnosis of such tumours during antenatal periods may in future allow intrauterine fetal interventional surgery for a premature fetus. The tumour was surgically dealt with successfully in each case on the third day after birth with good clinical results at the end of one year and eight months respectively.

Giant sacrococcygeal teratoma: a method of simple intraoperative control of hemorrhage

A method of emergency hemostasis and continuous intraoperative control of hemorrhage in giant sacrococcygeal teratoma, using an aortic snare, is described. A baby weighing 1,700 g with a 1,300-g sacrococcygeal teratoma was successfully operated using this technique.

[Angiographic and morphological findings in testis tumors (author's transl)]

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.

Arteriography of sacrococcygeal teratomas

Sacrococcygeal teratomas often present at birth as skin-covered caudal masses. Because of the variable intrapelvic and presacral extension of these tumors, high mortality from hemorrhage, variable blood supply, and occasional confusion with other caudal masses, preoperative arteriography is useful. The arteriographic findings in 4 neonates with sacrococcygeal teratoma are presented.

Primary retroperitoneal teratoma in adults: presentation of two cases and review of the literature

Retroperitoneal teratomas are rare in adults; they are malignant in 25.8% of cases. The authors report two benign cases in which radiologic examination was essential in establishing the diagnosis. Irregular calcifications, which are visible in 61.5% of reported cases, cannot be considered a sign of benignity, since 12.5% of calcified tumors were malignant. Because of the indeterminate course of the disease, surgical removal is indispensable.

Benign and malignant teratomas in children: analysis of 85 patients

Teratomas were observed in 85 infants and children. Fifty-eight (68%) were girls and 27 (32%) boys. Site of origin was sacrococcygeal in 55 patients (64.8%), mediastinal in ten (11.7%), gonadal in ten (11.7%), presacral in four (4.8%), retroperitoneal in three (3.5%), and cervical in three (3.5%). Sixty-seven (78.8%) teratomas were benign and 18 (21.1%) malignant. Malignant tumors were noted in 11 of 55 sacrococcygeal (20%), two of ten mediastinal (20%), three of eight ovarian (37.5%), and both testicular lesions. Cervical, retroperitoneal, and presacral tumors were benign. Age at diagnosis (greater than 1 month), presence of symptoms (urinary and colonic obstruction), and serum positive for alpha fetoprotein were indicators of malignancy in sacrococcygeal cases. Age was not a factor for teratomas at other sites. Tumor size, presence of calcification, and gross appearance (cystic or solid) did not relate to the tumor's benign or malignant nature. Three of four presacral tumors were associated with anorectal anomalies. Operative resection is the treatment of choice. Four deaths were related to operative hemorrhage. Four of five survivors with malignant teratoma received radiation and chemotherapy. A more aggressive role for combined adjunctive measures is suggested in cases of malignancy.

[Significance of the endodermal sinus tumor (Teilum) and of simplified teratoma of vitelline determination]

The histogenesis of yolk-sac tumors has been explained by a selective cloning for extra-embryonic entoblast amongst totipotent carcinoma stemcells. The diverses appearances of the tumor growths are expressed mainly in the range of cyto-differentiations of entoblastic tissue rather than in their ability to form structures which mimick the yolk-sac. The process is clearly apparent in embryoids which are becoming disorganized and during the course of experimentally induced mouse parietal endodermal carcinoma. The latter's appearance is strong evidence that the laws of specificity are obeyed. Human tumors should be analyzed through human embryology. Some paradoxical aspects emerge occasionally due to the angiogenesic capabilities of the neoplastic vitelline tissue, and to the correlations of this tissue with the stromal vascular response.