Sugar chain of alpha-fetoprotein produced in human yolk sac tumor.

The carbohydrate moiety of alpha-fetoprotein purified from human yolk sac tumors grown in nude mice was quantitatively released from the polypeptide chain as oligosaccharides by hydrazinolysis. The oligosaccharides were separated into a neutral and two acidic oligosaccharides by paper electrophoresis. By sequential exoglycosidase digestion in combination with per-O-methylation study and periodate oxidation, their structures were determined to be: Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(GlcNAc beta 1 leads to 4) (Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GlcNAc beta 1 leads to 4(Fuc alpha 1 leads to 6)GlcNAcOT, Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(GlcNAc beta 1 leads to 4) (Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GlcNAc beta 1 leads to 4(Fuc alpha 1 leads to 6)GlcNAcOT; and Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(GlcNAc beta 1 leads to 4) (Sia alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4 GlcNAc beta 1 leads to 4(Fuc alpha 1 leads to 6)GlcNAcOT, in which Gal is galactose, GlcNac is N-acetylglucosamine, Man is mannose, Fuc is fucose, Sia is sialic acid, and Subscript OT is the NaB3H4-reduced oligosaccharide.

Molecular properties of F9 embryoglycan recognized by a unique antibody in sera from patients with germ cell tumors.

Human antibody against an embryoglycan present on a mouse teratocarcinoma cell line F9 was found in sera from 16 of 29 patients with embryonal carcinoma, yolk sac tumor, immature teratoma, and choriocarcinoma of gonadal and extragonadal origins by Farr assay. In contrast, none of the sera from patients (77 cases) with dysgerminoma, seminoma, germinoma, and mature teratoma or from patients (118 cases) with nongerm cell types of ovarian tumors contained this antibody. The antigenic embryoglycan was of high molecular weight (Mr greater than 70,000) on Sephacryl S300 column chromatography and carried binding sites for Grifonia simplicifolia agglutinin-1. The antigenic embryoglycan was also found in F9 cell-cultured medium. Absorption of patients' sera with synthetic Blood Group B trisaccharides failed to remove the antibody against F9 embryoglycan. None of these patients' sera showed higher hemagglutination titer to rabbit erythrocytes than the normal range. In contrast, alpha-galactosyl carbohydrates obtained from Ehrlich ascites tumor cells effectively inhibited the binding of patients' sera with F9 embryoglycan. These results indicate that the human antibody against F9 embryoglycan recognizes alpha-galactosyl structures that are distinct from B blood group antigen, but are cross-reactive with alpha-galactosyl structures on Ehrlich ascites cells.

Intracranial germ cell tumors: pathobiological and immunohistochemical aspects of 70 cases.

Seventy cases of histologically verified intracranial germ cell tumor were reviewed: 43 germinomas, 16 immature teratomas, seven mature teratomas, two embryonal carcinomas, one choriocarcinoma, and one yolk sac tumor. The male-to-female ratio was 2.6:1. The average age was 19 years in patients with germinoma, 11 years in patients with immature teratoma, and 17 years in patients with mature teratoma. Duration of symptoms averaged 19 months for germinoma, three months for immature teratoma, and 11 months for mature teratoma. Sixty-six lesions were located in the midline. Fifty-eight percent of the germinomas arose anterior to the pineal gland, whereas 29% of the immature and 14% of the mature teratomas were located anteriorly. The histologic appearance of the germinomas was indistinguishable from that of the usual testicular seminoma. The immature teratomas contained tissue from all three germ layers and exhibited morphologic features of fetal tissue. Of 14 immature teratomas, seven contained, in addition, foci of other malignant germ cell elements; thus, there were two teratocarcinomas, two lesions with germinoma and immature teratoma, two lesions with extensive rhabdomyoblastic differentiation in an immature teratoma, and one lesion with both germinoma and embryonal carcinoma in addition to immature teratoma. The seven mature teratomas consisted of fully differentiated epithelial and mesenchymal tissues. In 23 cases, immunoperoxidase stains for human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP), and carcino-embryonic antigen (CEA) revealed patterns which, with minor exceptions, were essentially identical to those found in genital germ cell lesions. Survival was longest for patients with germinomas. In classifying germ cell tumors of the central nervous system, the World Health Organization's (WHO) classification of testicular germ cell tumors is preferable to its present classification of intracranial germ cell tumors.

Yolk sac tumor of the anterior mediastinum. Case report with light- and electron-microscopic examination and immunohistochemical study of alpha-fetoprotein.

A case of yolk sac tumor of the anterior mediastinum was studied by light and electron microscopy and found to have characteristic patterns which were similar to a neoplasm of gonadal origin. These findings, in addition to the immunohistochemical identification of alpha-fetoprotein in the tumor, indicated that the neoplasm was germ cell in origin. A brief review of previously reported cases is included. Prognosis of the patients with yolk sac tumor of the anterior mediastinum was generally dismal; however, those patients with tumors incidentally found but completely excised survived without evidence of reucrrence.

The differential diagnosis of yolk sac tumor and seminoma. Usefulness of cytokeratin, alpha-fetoprotein, and alpha-1-antitrypsin immunoperoxidase reactions.

Yolk sac tumor and seminoma may have a similar appearance in focal areas. Small biopsies may therefore be difficult to interpret. The authors studied 20 yolk sac tumors and 21 seminomas to investigate the utility of immunohistochemical markers in this differential diagnosis. All yolk sac tumors stained positively for cytokeratin (CK) but so did 43% of seminomas. The CK positivity of yolk sac tumors was generally more diffuse and intense, however, there was an overlap in the spectrum of intensity of CK positivity in yolk sac tumor and seminoma. Alpha-fetoprotein (AFP) was a less sensitive (55%) marker for yolk sac tumor than CK, but AFP was quite specific in this differential diagnosis because no seminoma stained for AFP. Alpha-1-antitrypsin was not a very useful marker because of poor sensitivity and specificity. The interpretation of light microscopic patterns remains of paramount importance in the differentiation of solid yolk sac tumor from seminoma.

Localization of alpha-fetoprotein and human chorionic gonadotropin to specific histologic types of nonseminomatous testicular cancer.

We used an indirect immunoperoxidase technique to localize alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) to specific histologic types of testicular germ cell cancers. Among 20 nonseminomatous tumors studied, yolk sac tumor reacted for AFP in 13 of 15 cases, teratoma in 3 of 11 cases, and embryonal carcinoma in 3 of 14 cases. Syncytiotrophoblasts alone reacted for HCG in 14 of 15 cases, and syncytiotrophoblasts associated with choriocarcinoma reacted for HCG in 2 of 2 cases. There was a close correlation between the tissue demonstration of AFP and HCG and elevated serum levels of AFP and HCG, respectively. We conclude that in nonseminomatous testicular cancer yolk sac tumor is the primary site of synthesis of AFP, and syncytiotrophoblasts are the only site of synthesis of HCG.

Detection of AFP and HCG in metastatic testicular cancer after treatment with chemotherapy or radiation therapy.

We used an indirect immunoperoxidase technique to detect alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) in tissue sections of nine metastatic germ cell tumors excised after treatment with chemotherapy or radiation therapy, and correlated the results with the serum levels of AFP and HCG. In all but 1 case yolk sac tumor (YST) was the only histologic type that reacted for AFP (AFP+) and syncytiotrophoblasts (STB) were the only histologic type that reacted for HCG (HCG+). Among 5 cases with normalization of the serum AFP before surgery, 3 were associated with YST-/AFP-, 1 with YST+/AFP+, and 1 with YST+/AFP- metastases; and among 4 cases with normalization of the serum HCG all were associated with STB-/HCG- metastases. Among 3 cases with persistent elevation of the serum AFP, 1 was associated with YST+/AFP+, 1 with YST+/AFP-, and 1 with YST-/AFP- metastases; and of 2 cases with persistent elevation of the serum HCG, 1 was associated with STB-/HCG- and 1 with STB+/HCG+ metastases. These data suggest that marker normalization in the face of persistent tumor results primarily from eradication of YST and STB, but also from treatment-induced inhibition of AFP and HCG synthesis or secretion.

Cellular localization of AFP, hCG and its free subunits, and SP1 in embryonal carcinoma of the testis and ovary.

An immunohistological study of AFP, hCG and its free subunits, and SP1 was investigated in 10 cases of non-seminomatous germ cell tumors of the testis and ovary. AFP was demonstrated in mononuclear embryonal tumor cells within embryonal carcinoma in a narrow sense, frequently in association with yolk sac tumor. AFP was more consistently demonstrated in vacuolated or elongated cells of yolk sac tumor, in which continuous transformation from tubular patterns of embryonal carcinoma was shown with positive reactions for AFP. The hCG was demonstrated in syncytiotrophoblastic giant cells scattered among the embryonal carcinoma, but rarely in mononuclear large cells. The occurrence of hCG and beta subunit was more frequently observed than a subunit or SP1, suggesting the unbalanced synthesis of hCG and free subunit in choriocarcinomatous element associated with embryonal carcinoma. These findings support the view that embryonal carcinoma has a developmental potential to the extra-embryonic components of both choriocarcinoma and yolk sac tumor.

The pluripotential nature of the mesenchyme-like component of yolk sac tumor.

Germ cell neoplasms were reviewed for the investigation of a mesenchyme-like component of yolk sac tumor (YST) characterized by spindle cells with few mitoses in a myxoid, vascular background. Nineteen YSTs with this pattern were identified. The mesenchyme-like component of these YSTs appeared to derive from the epithelial elements of YST, since cytokeratin as well as vimentin positivity occurred in the spindle cells of the mesenchyme-like areas and foci of epithelial-spindle cell transition were present. In some cases the mesenchyme-like component showed differentiated mesenchymal elements (usually skeletal muscle). Similar features were identified in 13 chemotherapy-treated cases of YST that consisted only of this mesenchyme-like component. The mesenchyme-like component of YST appears to represent a chemoresistant, pluripotential cell population arising from metaplasia of YST epithelium; it may give rise to sarcomas occurring in some patients with treated germ cell tumors.

Frequency of intratubular germ cell neoplasia with invasive testicular germ cell tumors. Histologic and immunocytochemical features.

Intratubular germ cell neoplasia (ITGCN) has been regarded as the preinvasive stage of testicular germ cell tumors. We evaluated its frequency in 53 testicular germ cell tumors and determined whether immunohistochemical stains for alpha-fetoprotein, human chorionic gonadotropin, carcinoembryonic antigen, and ferritin demonstrated an advantage in its detection in comparison with hematoxylin-eosin and periodic acid-Schiff (PAS) stains. Residual seminiferous tubules were found at the periphery of the invasive neoplastic foci in 47 cases. Intratubular germ cell neoplasia was detected in several or multiple seminiferous tubules in 46 cases (98%). Exquisite localization of PAS-positive intracellular granules was present in all but one case of ITGCN. Focal immunocytochemical positivity for human chorionic gonadotropin, carcinoembryonic antigen, and ferritin was noted in 2.3% of cases. We conclude that ITGCN is present in most invasive germ cell tumors and the PAS stain is very reliable in its demonstration. Antigenic expression of the proteins that we examined is extremely limited in these primordial germ cells.

[Primary endodermal sinus tumor of the fourth ventricle (author's transl)].

A case, a 18-year-old male, of an endodermal sinus tumor (yolk sac tumor) in the fourth ventricle, was reported. The patient had a month history of headache, vomiting and gait disturbance prior to the hospitalization, when he admitted to our service he was in lethargic condition with left cerebellar ataxia and horizontal nystagmus. Lumbar tap revealed clear CSF under normal pressure of 110 mm H2O with the CSF protein of 432.5 mg/dl and cell count of 147/3. The vertebral angiography demonstrated space occupying lesion in the posterior fossa. Plain CT demonstrated only disappearance of the fourth ventricle and slightly dilated bilateral ventricles and third ventricle. However diffuse high density area around the fourth ventricle was demonstrated and the wall of bilateral anterior horn was slightly enhanced, after injection of contrast media. There was no other abnormal findings around the pineal region. Suboccipital craniectomy was performed and the tumor was totally removed macroscopically. The tumor was situated in th floor of the fourth ventricle and infiltrated into the fourth ventricular wall and th adjacent cerebellar tissue. The tumor was with soft, greyish color and extremely vascular. Histologically the tumor was diagnosed as endodermal sinus tumor according to Teilum's classification. There were stellate cells arranged in a loose with vacuolated network which formed cystic cavities and a complicated network of honeycomb appearance with a system of communicating cavities and channels. Various size of intra- and extracellular PAS-positive hyaline globules were also seen. Glomerular-like structure (Schiller-Duval body) was not observed. Immunoperoxidase study clearly demonstrated the presence of intra- and extracytoplasmic alpha-fetoprotein granules in the tumor tissue. The amount of the serum alpha-fetoprotein, measured by radioimmunoassay, showed 400 ng/ml. After irradiation in the posterior fossa (5000 rad) the patient was discharged. Three months later, follow up CT demonstrated small high density area in the anterior horn of the left lateral ventricle, so he was rehospitalised. Irradiation in the whole brain was again administered. The tumor was very radiosensitive. CT, after 800 rad, demonstrated complete disappearance of the tumor. After irradiation totally (3000 rad), he discharged with left cerebellar ataxia.

[Endodermal sinus tumor in childhood. Clinical study of 6 cases (author's transl)]. / Il tumore del seno endodermico in età pediatrica. Studio clinico di 6 casi.

Six children with yolk sac tumor, 3 occurring in gonadal sites and 3 in extragonadal ones, were studied with respect to pathological features, laboratory findings and clinical course. Their histological appearance was similar regardless of the site of origin. The prognosis was poor, but all the cases exhibited objective response to chemotherapy. Two children are alive and off therapy from 27 and 60 months. Three of the six patients in which serum alfa-fetoprotein determinations were performed showed positive results. The demonstration of alfa-fetoprotein in the serum of these patients could prove to be of prognostic value, indicating the presence of residual or recurrent disease. It is advisable to gather cases from many Institutions in order to specify prognostic factors, to know the natural history of this tumor and to prepare an effective therapeutic program.

Nuclear deoxyribonucleic acid content (ploidy) of endodermal sinus (yolk sac) tumor.

Paraffin sections from 30 endodermal sinus (yolk sac) tumors were Feulgen-stained, and nuclear DNA content (ploidy) was assessed through DNA cytophotometry using the microTICAS image analysis system. The series consisted of 20 ovarian, 8 testicular, 1 sacrococcygeal, and 1 mediastinal tumors. Of the 30 endodermal sinus (yolk sac) tumors 29 were shown to be aneuploid, whereas the remaining tumor which exhibited the recently described primitive intestinal or enteric pattern was diploid and may thus be considered a neoplasm showing a somewhat higher degree of differentiation as compared to tumors showing the other histologic patterns of endodermal sinus (yolk sac) tumors.

[An ultrastructural study of human ovarian yolk sac tumor--an investigation of its histogenesis compared to that of human yolk sacs (author's transl)].

For the purpose of investigating the histogenesis of the yolk sac tumor, 7 cases of the tumor and 9 cases of human yolk sac were used. Histological, ultrastructural investigations together with immunofluorescent antibody examinations revealed the following results. Ultrastructurally yolk sac endodermal cells prior to the 7th week of pregnancy were proved to have microvilli, abundant glycogen which formed rosette, parallel arranged rough endoplasmic reticulum (rER), mitochondria closely associated with rER and ovoid electron dense amorphous granules which showed positive diastase-resistant PAS-reaction. Morphologically endoderm after the 8th week of pregnancy showed degenerative changes. Light microscopically the tumors showed Schiller-Duval body, endodermal sinus structure and clear-cells endoblastic pattern, but ultrastructurally the tumor cells of these three types showed approximately similar appearances. Ultrastructural features of the tumor seem to resemble those of the yolk sac endoderm before the 7th week of pregnancy. The tumor cells which form the epithelial mantling of Schiller-Duval body closely resembled the endodermal cells facing the yolk sac cavity with respect to the presence of abundant glycogen granules, rER, mitochondria, short irregular microvilli on the cell surface and remarkable nucleolus with thread-like nucleolonema. Both the tumor cells facing the endothelial cell and those which form the endodermal sinus structure and clear-cells endoblastic pattern resembled the endodermal cells facing the mesenchyma in view of the features of intracellular organelles, the presence of extracellular basement membrane-like substances and tubular structure.

Mediastinal yolk sac tumor: ultrastructural and immunofluorescent studies.

Primary mediastinal yolk sac tumor is rare. In this report, a case of a 32-year-old male with a mediastinal yolk sac tumor was studied by light, electron, and immunofluorescent microscopy. A positive immunofluorescent reaction to alpha-fetoprotein (AFP) correlated with the PAS-positive hyaline globules and electron-dense deposits seen in intracellular and extracellular locations. Serum AFP is a useful tumor marker for monitoring the results of therapy. Review of the literature indicates that the prognosis for patients with yolk sac tumor is generally poor.