Intrapulmonary and gastric teratoma : report of two cases.
(9/1513)
The lung and stomach are very unusual sites for teratoma. The histologic findings of intrapulmonary and gastric teratomas are not different from those arising in usual sites, such as the ovary or testis. However, preoperative diagnosis is sometimes difficult to make partly because of unusual location. We report here two cases of teratoma, one intrapulmonary teratoma and the other gastric. The intrapulmonary teratoma in our study had an endobronchial tumor growth, which rules out mediastinal teratoma. Meanwhile gastric teratomas usually present as a submucosal tumor and most cases are reported in infancy and childhood. Gastric teratoma in this study occurred in a 27-year-old man. To the best of our knowledge, this case of intrapulmonary teratoma is the eighth and the gastric teratoma is the first to be reported in Korea. (+info)
Hypercalcemia accompanied by hypothalamic hypopituitarism, central diabetes inspidus and hyperthyroidism.
(10/1513)
We present here a case of prominent hypercalcemia accompanied by hypothalamic tumor and Graves' disease. A 24-year-old man with hypothalamic tumor showed hypopituitarism, central diabetes inspidus (DI) and hyperthyroidism. Nausea, loss of thirst and appetite, and general fatigue were found with the unveiling of hypercalcemia and hypernatremia. Parathyroid hormone (PTH) and 1alpha-dihydroxyvitamin D levels were suppressed with a normal range of PTH-related protein values. One-desamino-(8-D-arginine)-vasopressin (DDAVP) and half-saline administration normalized hypernatremia, while hypercalcemia was still sustained. Administration of cortisone acetate and thiamazole reduced the elevated serum Ca level. In the present case, concurrent hyperthyroidism was assumed to accelerate skeletal mobilization of calcium into the circulation. Hypocortisolism and central DI was also considered to contribute, to some extent, to the hypercalcemia through renal handling of Ca. (+info)
A vital role for glycosphingolipid synthesis during development and differentiation.
(11/1513)
Glycosphingolipids (GSLs) are believed to be integral for the dynamics of many cell membrane events, including cellular interactions, signaling, and trafficking. We have investigated their roles in development and differentiation by eliminating the major synthesis pathway of GSLs through targeted disruption of the Ugcg gene encoding glucosylceramide synthase. In the absence of GSL synthesis, embryogenesis proceeded well into gastrulation with differentiation into primitive germ layers and patterning of the embryo but was abruptly halted by a major apoptotic process. In vivo, embryonic stem cells deficient in GSL synthesis were again able to differentiate into endodermal, mesodermal, and ectodermal derivatives but were strikingly deficient in their ability to form well differentiated tissues. In vitro, however, hematopoietic and neuronal differentiation could be induced. The results demonstrate that the synthesis of GSL structures is essential for embryonic development and for the differentiation of some tissues and support the concept that GSLs are involved in crucial cell interactions mediating these processes. (+info)
Telomerase activity in germ cell cancers and mature teratomas.
(12/1513)
BACKGROUND: An inverse relationship has been reported between the presence of telomerase enzymatic activity and the induction of differentiation in human tumor cell lines. Male germ cell tumors represent an attractive clinical model to assess this relationship further because high telomerase activity is present in normal germ cell progenitors and in embryonal carcinomas that can differentiate into mature teratomas. To investigate how telomerase activity and the differentiation state of germ cell tumors are related, telomerase activities and telomere lengths were measured in benign testicular tissues, germ cell cancers, and mature or immature teratomas. METHODS: By use of a modified telomeric repeat amplification protocol (TRAP) assay, telomerase activity was measured in four specimens of benign testicular tissue, in 27 germ cell cancers, in seven mature teratomas, and in one immature teratoma. Telomere lengths were measured in all specimens by restriction digestion of genomic DNA and Southern blot hybridization analysis. Associations between telomerase activity and tissue histopathology were assessed with two-sided Fisher's exact tests. RESULTS: Telomerase activity was detected in all examined germ cell cancers and in the benign testicular tissue specimens. In marked contrast, telomerase activity was not detected in any mature teratoma (P<.0001). Very long telomeres were detected in some mature teratomas, consistent with telomerase repression as a late event in teratoma formation. The immature teratoma, with malignant transformation, had high telomerase activity. CONCLUSION: Telomerase is active in germ cell cancers and repressed in mature teratomas. The absence of telomerase activity may contribute to the limited proliferative capacity of mature teratomas. These findings support the existence of an inverse relationship between telomerase activity and the differentiation state of clinical germ cell tumors. (+info)
Clinicopathological characteristics of atypical teratoid/rhabdoid tumor.
(13/1513)
The clinicopathological features of atypical teratoid/rhabdoid tumor, a new entity among malignant pediatric brain tumors, and the differential diagnosis from primitive neuroectodermal tumor (PNET)/medulloblastoma, and germ cell tumor are described. Histologically, atypical teratoid/rhabdoid tumor is defined as a polymorphous neoplasm often featuring rhabdoid, PNET, epithelial, and mesenchymal components. Atypical teratoid/rhabdoid tumors usually include PNET components and occur mainly in the posterior fossa, so mimic medulloblastoma. Atypical teratoid/rhabdoid tumor is characterized by the cytogenetic finding of monosomy 22 rather than i(17q). The tumor is similarly mistaken for PNET at supratentorial sites. Germ cell tumors also enter into the differential diagnosis due to their histological immunophenotypic diversity, particularly features indicative of epithelial and mesenchymal differentiation. Nonetheless, the remarkable spectrum of tissues that typify teratoma is absent in atypical teratoid/rhabdoid tumor. The same is true of germ cell marker in tumor tissues and serum. The prognosis of atypical teratoid/rhabdoid tumor is far less favorable than that of PNET/medulloblastoma of malignant or germ cell tumor. Meta-analysis of 133 cases, including 15 new and 118 reported cases, confirm that atypical teratoid/rhabdoid tumor is as a clinicopathological entity and emphasizes the necessity for distinguishing this unique tumor from other pediatric central nervous system neoplasms. (+info)
Factors that increase the risk of leakage during surgical removal of benign cystic teratomas.
(14/1513)
The contents of mature cystic teratomas can be a potent irritant resulting in chemical peritonitis. Using a retrospective cohort, we examined the various risk factors for leakage of benign cystic teratomas during laparoscopy and laparotomy. Cyst leakage of the benign cystic teratoma contents was the primary endpoint. In all, 158 women underwent surgery for a total of 178 ovarian benign cystic teratomas. Statistical analysis was performed using chi(2), Mann-Whitney U and multivariate logistic regression analysis. A total of 115 benign cystic teratomas was successfully removed without intra-operative leakage and 63 underwent intra-operative leakage either at laparoscopy or laparotomy. The likelihood of success of removing the benign cystic teratoma intact was unrelated to age, pre-operative size or surgical technique. There was no difference among cystectomies performed by laparotomy in surgeon experience or the presence of adhesions. However, surgeons with more laparoscopic experience (>35 laparoscopies/year) were less likely to have intra-operative leakage (relative risk: 0.5, 95% confidence interval: 0.2, 1.2) compared to surgeons with less experience (<20/year) at cystectomy (26.1 versus 51.2% respectively). Oophorectomy significantly reduced the frequency of intra-operative leakage at both laparoscopy and laparotomy (14.7%). These findings suggest that laparoscopic experience can reduce the risk of leakage at cystectomy. At laparotomy, lack of surgeon postgraduate years of experience was not a risk factor for leakage. (+info)
Intraglomerular metastasis: a necropsy study.
(15/1513)
Intraglomerular metastasis is a rare phenomenon. Four cases are reported here. The primary malignancies in these four cases were squamous cell carcinoma of the lung, adenocarcinoma of pancreas, haematological malignancy with a malignant intrapulmonary teratoma, and undifferentiated pleural mesothelioma. There was no significant renal functional impairment in any case except for mild proteinuria in one. Histopathology showed tumour cells in the mesangium, in the glomerular tufts replacing the endothelial cells, as well as in an extracapillary location replacing the parietal cells. In one case, tumour cells formed crescent-like structures. Such tumour deposits were better appreciated with special stains. The presence of intraglomerular metastasis indicates dissemination of the malignancy and hence a poor prognosis even though there is no significant impairment of renal function. (+info)
Spontaneous hemothorax secondary to immature teratoma of the mediastinum.
(16/1513)
Spontaneous hemothorax in a 20-year-old boy was caused by rupture of an immature teratoma of the mediastinum. The tumor bled spontaneously into the right pleural space. This life-threatening complication necessitated emergency surgery. The unusual cause and the interesting clinical course of spontaneous hemothorax are described. (+info)