Developmental Changes of Amniotic Fluid Alpha-Fetoprotein Subtractions in Early Gestation

ABSTRACT: Using both concanavalin A crossed-line affinity immunoelectrophoresis and lentil lectin crossed-line affinity immunoelectrophoresis, developmental changes of alpha-fetoprotein (AFP) subfractions were studied in 11 samples of human amniotic fluid obtained between 43 and 121 days of gestation. In the amniotic fluid at 43 or 48 days of gestation, only subfractions produced by the yolk sac were evident. The initial appearance of the subfractions produced by the fetal liver was first detected at 51 days of gestation. Percentages of liver-originated subfractions rose rapidly with gestational age and reached a level of 50% at 54 days of gestation. The subfractions produced by the yolk sac disappeared from the amniotic fluid at 121 days of gestation. These findings suggest that, in early gestation, the yolk sac is mainly responsible for the fetal AFP synthesis and that initiation of AFP production by the fetal liver takes place between 48 and 51 days of gestation. In the present study, attention was also given to the origin of four subfractions separated by the lentil lectin crossed-line affinity immunoelectrophoresis.     

Bowel loop in an ovarian tumor: Grossly visible, completely developed intestinal loop in mature cystic teratoma of malignant mixed germ cell tumor

Although a gastrointestinal-type epithelium is observed in 7–13% of mature cystic teratoma cases, the occurrence of a grossly visible, organized gastrointestinal loop formation is very rare. Presented here is the case of a 14-year-old girl with malignant mixed germ cell tumor in the ovaries. In her left ovary a grossly visible, intestinal loop, 9 cm long, with hanging mesentery attached to the cystic wall of a mature cystic teratoma associated with a yolk sac tumor was observed, and in her right ovary another mature cystic teratoma was observed. Microscopy of the intestinal loop indicated a well-organized, intact layer of small intestinal wall. The yolk sac tumor predominantly had a polyvitelline pattern. Previously, gastrointestinal wall or epithelium that was identified on microscopy has been reported. To the authors' knowledge this is the first case report of the formation of a grossly visible, completely developed intestinal loop in a malignant mixed germ cell tumor.     

HUMAN TESTICULAR GERM CELL TUMORS IN VITRO and IN ATHYMIC NUDE MICE

Four cell lines derived from pure and mixed types of human testicular germ cell tumors in vitro and in nude mice were examined by light and electron microscopies. The NEC8 and NEC15 cell lines in vitro were composed of embryonal carcinoma cells with potentiality of trophoblastic differentiation. All of the tumors formed in nude mice by both cell lines were pure embryonal carcinomas. On the other hand, the NEC14 and ITO-II cell lines showed morphological differentiation from embryonal carcinoma cells to trophoblastic cells and to yolk sac tumor cells in vitro. In nude mice, these cell lines formed mixed tumors which consisted of embryonal carcinoma, yolk sac tumor, immature teratoma or trophoblastic cells. Our data suggest that some embryonal carcinomas have multipotentiality of morphological differentiation but that others have little such potentiality.     

Human testicular germ cell tumors in vitro and in athymic nude mice

Four cell lines derived from pure and mixed types of human testicular germ cell tumors in vitro and in nude mice were examined by light and electron microscopies. The NEC8 and NEC15 cell lines in vitro were composed of embryonal carcinoma cells with potentiality of trophoblastic differentiation. All of the tumors formed in nude mice by both cell lines were pure embryonal carcinomas. On the other hand, the NEC14 and ITO-II cell lines showed morphological differentiation from embryonal carcinoma cells to trophoblastic cells and to yolk sac tumor cells in vitro. In nude mice, these cell lines formed mixed tumors which consisted of embryonal carcinoma, yolk sac tumor, immature teratoma or trophoblastic cells. Our data suggest that some embryonal carcinomas have multipotentiality of morphological differentiation but that others have little such potentiality.     

Rat Yolk Sac Tumor: Biological Aspects and Microheterogeneity of AFP

α-Fetoprotein (AFP)-producing yolk sac tumors were established in rats as transplantable tumor lines growing in either solid or ascitic form. AFP levels in the ascites and in the serum of recipients were quite high, but higher in castrated female rats than male rats. The tumor cells were cultured also in vitro and showed synthesis of AFP and albumin. AFP produced by the yolk sac tumors was investigated comparatively with AFP produced by a hepatoma. There was no remarkable difference between two AFPs in behavior in gel filtration; however, AFP of yolk sac tumors migrated more slowly than that of hepatoma in immunoelectrophoresis. However, the mobilities of two AFP preparations became same after desialization by neuraminidase treatment. This fact suggests that AFP of yolk sac tumors contains sialic acids in smaller amount than that of hepatomas.     

The value of cytology in the diagnosis of extragonadal germ cell tumors

Extragonadic germinal tumors are frequently mixed tumors. When a metastatic sacrococcygeal teratoma is clinically suspected in children, a yolk-sac tumor component could be judiciously demonstrated by either an elevated serum level of alphafoetoprotein (AFP), or fine needle aspiration cytology. We report the case of a 25 month aged girl presenting a metastatic sacrococcygeal tumor (lymph node and bone metastasis) with high level of AFP (34.100 microg/ml). Fine needle aspiration cytology identified the yolk sac tumor component, characterized by papillae and glandular clusters, composed of pale isomorphic cells with vesicular and nucleolated nucleus and some intracytoplasmic hyaline globules. The yolk sac tumor component could not be identified in the sacrococcygeal surgical specimen, exclusively composed of immature teratoma.     

Ovarian gonadoblastoma with mixed germ cell tumor in a woman with 46, XX karyotype and successful pregnancies

An extremely rare case of unilateral gonadoblastoma with mixed germ cell tumor arising in the ovary of a 27-year-old woman with 46,XX karyotype and two successful pregnancies is reported. The mixed germ cell tumor was composed of choriocarcinoma, embryonal carcinoma, yolk sac tumor, immature teratoma and dysgerminoma. The patient has been well, without evidence of disease for over 10 years since her first surgery and adjuvant chemotherapy.     

Ovarian malignant mixed germ cell tumor with clear cell carcinoma in a postmenopausal woman

Malignant germ cell tumors of the ovary are very rare and account for about 2-5% of all ovarian tumors of germ origin. Most patients are adolescent and young women, approximately two-thirds of them are under 20 years of age, occasionally in postmenopausal women. But clear cell carcinoma usually occurs in older patients (median age: 57-year old), and closely related with endometriosis. Here we report a case of a 55-year old woman with right ovarian mass that discovered by B ultrasonic. Her serum levels of human chorionic gonadotropin (hCG) and α-fetoprotein (AFP) were elevated. Pathological examination revealed the tumor to be a mixed germ cell tumor (yolk sac tumor, embryonal carcinoma and mature teratoma) with clear cell carcinoma in a background of endometriosis. Immunohistochemical staining showed SALL4 and PLAP were positive in germ cell tumor area, hCG, CD30 and OCT4 were positive in epithelial-like cells and giant synctiotrophoblastic cells, AFP, AAT, CD117 and Glyp3 were positive in yolk sac component, EMA and CK7 were positive in clear cell carcinoma, CD10 was positive in endometrial cells of endometriotic area. She was treated with surgery followed by seven courses of chemotherapy. She is well and serum levels of hCG and AFP have been decreased to normal levels.     

儿童未成熟畸胎瘤的临床病理与生物学行为分析

目的探讨儿童未成熟畸胎瘤病理形态特征、生物学行为的评估及治疗方法的选择。方法收集39例未成熟畸胎瘤临床资料,观察病理形态,并结合免疫组织化学cyclinD1、p27、Ki-67标记及30例随访资料对预后判断进行分析。结果39例未成熟畸胎瘤中位于骶尾部12例、睾丸12例、腹膜后5例、卵巢4例、腹部4例、纵隔2例;病理分级1级16例、2级8例、3级15例。7例含灶状卵黄囊瘤结构（YST）,用于病理诊断分级的未成熟神经上皮组织主要包括：原始神经管、未成熟的菊形团样结构、未分化的神经母细胞、原始神经外胚层样组织结构。cyclinD1在各病理分级中的阳性表达分别是3A、9例;p27过表达分别8、3、6例;Ki-67过表达分别是3A、13例。随访到30例,2例病理分级3级的病例术后复发,其中1例含灶状YST;1例成熟畸胎瘤术后复发。结论cyclinD1、Ki-67的表达与病理分级有关,可作为预后的判断参考指标;p27的表达与病理分级无相关性,可进行肿瘤细胞的定性观察。儿童未成熟畸胎瘤的预后不同于成人,患者年龄小于1岁的骶尾部单纯性未成熟畸胎瘤,临床手术切除完整,病理分级在2级以下,不进行手术后化疗,但应密切随访;1岁以内的睾丸单纯性未成熟畸胎瘤,临床Ⅰ期,无论病理分级如何,不需要进行术后化疗,但应密切随访。儿童卵巢未成熟畸胎瘤病理分级2级以上,不论年龄,应手术后进行化疗。未成熟畸胎瘤伴有灶状YST结构与复发有关。     

Teratome des Ovars

Teratomas are the most frequent germ cell tumors of the ovary. Two main groups can be distinguished: mature and immature teratomas. Mature teratomas are benign tumors, which are most often composed of derivatives of two or three germ cell layers. Only in rare cases is the transition into a malignant tumor observed (most often squamous cell carcinoma). In contrast, immature teratomas are malignant ovarian tumors. They contain immature tissue elements in addition to the mature components, most often consisting of immature neural tissue. Histologically, this tumor component can be identified as neurotubules or rosettes. The proportion of immature tissue elements defines the grade of immaturity. Four grades have been defined in to the WHO classification. Grade 0 represents a mature teratoma. With the exception of childhood cases, grade 2 and 3 immature teratomas are treated with chemotherapy. In childhood cases, foci of yolk sac tumor (YST) must be looked for, since this determines the prognosis. If a focus of YST is present, the patient is treated with chemotherapy. Both in cases of mature and immature teratoma, peritoneal implants can be found (gliomatosis peritonei), which are also graded. In cases of immature peritoneal implants, patients are also treated with chemotherapy. Gliomatosis peritonei is most likely derived from metaplasia of subperitoneal stem cells; it does not represent a metastatic disease of the ovarian teratoma.     

Primary juxtaovarian yolk sac tumor concurrent with an ipsilateral ovarian mature teratoma in an adult woman: a rare association

Objectives: Yolk sac tumor (YST) is a rare neoplasm that primarily occurs in the ovary in children and young women. Previously, it has been reported that the teratomatous components can be recognized in part of YSTs or appear in the contralateral ovary. Here, we report a rare case of an adult woman with a juxtaovarian YST concurrent with an ipsilateral ovarian mature teratoma. Methods: A 47-year-old woman found a pelvic mass for nine days and subsequently underwent debulking operation. The specimens were evaluated for detailed characterizations through gross examination, microscopy and immunohistochemistry. A literature review was performed and the pathogenesis was briefly discussed about the generation of an extraovarian YST concurrent with a teratoma. Results: The right juxtaovarian tumor showed typical histological patterns of YST. Immunostaining demonstrated the YST nature of Gly-3 and AFP positive tumor cells. The ipsilateral ovarian tumor was a common mature cystic teratoma with chronic fibrotic changes. According to the differences of the origin and the differentiation of the two germ cell tumors, we suspect that the occurrence of the teratoma is earlier than the YST. Conclusions: To our knowledge, this is the first report of an adult woman with a juxtaovarian YST concurrent with an ipsilateral ovarian mature teratoma.     

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.     

Germ cell tumours of the ovary: selected topics

We discuss germ cell tumours of the ovary, beginning with dysgerminoma as it is the most common malignant germ cell tumour in this location. Issues in differential diagnosis are highlighted as this tumour is associated with an excellent outcome nowadays and can be confused with small cell carcinoma, clear cell carcinoma, and rarely other neoplasms.The many patterns of yolk sac tumour are noted including the recently emphasized solid growth that may mimic dysgerminoma. Immunohistochemical stains are helpful in the diagnosis of both these primitive tumours, both being SALL4 positive and dysgerminoma expressing OCT4, D2-40 and c-KIT and yolk sac tumour having been recently reported to be GATA3 positive. Glypican-3 is also positive in yolk sac tumour but should be used with caution as it is often expressed in surface epithelial carcinomas, particularly clear cell carcinoma which can be in its differential. Where the fascinating polyembryoma should be placed in the classification of ovarian tumours is briefly considered.In the teratoma family emphasis is placed on the gross differences between the mature cystic and immature forms. The most important categories of monodermal teratoma are then considered emphasizing their varied problems in differential diagnosis.     

Yolk sac tumor of the stomach with an adenocarcinomatous component: A case report with immunohistochemical analysis

A 56-year-old male treated for a gastric yolk sac tumor with an adenocarcinomatous component is described. A mixed area of reticular and glandular neoplastic components was morphologically identified in this tumor. Immunohistochemically, the yolk sac tumor expressed alpha-fetoprotein (AFP), placental alkaline phosphatase (PLAP), and cytokeratin, but was negative for carcinoembryonic antigen (CEA). The adenocarcinoma was positive for CEA and cytokeratin, partially positive for PLAP, and negative for AFP. In the mixed area, the tumor cells were positive for cytokeratin, weakly expressed AFP and PLAP, and sporadically stained for CEA both in the reticular and glandular components. This area was identified as a transitional area of the yolk sac tumor and adenocarcinoma. These findings demonstrate that the yolk sac and adenocarcinomatous components are closely related. It also suggests that the tumor arose from multipotential neoplastic mucosal epithelial cells with both yolk sac and gastric mucosal phenotypes.     

Intratubular germ cell neoplasia in an infantile testis with immature teratoma

A case of intratubular germ cell neoplasia adjacent to an immature teratoma is described in an 8-month-old boy with normally descended testes. The pattern of intratubular germ cell neoplasia in the infantile testis appeared different from that in the adult, but the abnormal germ cells were morphologically and immunohistochemically similar. In the few previous reports, which have investigated infantile testicular tissue for the presence of intratubular germ cell neoplasia adjacent to germ cell tumours, intratubular germ cell neoplasia in conjunction with a yolk sac tumour and mature teratoma have not been found, and cases with immature teratoma have not been reported. The presence of intratubular germ cell neoplasia in conjunction with immature teratoma and its apparent absence in conjunction with the mature form and with yolk sac tumour may indicate difference in tumour development. Whether there is a true difference in the occurrence of intratubular germ cell neoplasia in the infantile testis according to the various types of germ cell tumours remains, however, to be proven by investigations of more cases.     

Fine-needle aspiration cytology of an endometrioid-like variant of yolk sac tumor.

A 36-year-old male with a history of immature teratoma and embryonal carcinoma of the testis was admitted to the hospital for abdominal pain and fever. A CT scan revealed a large right abdominal mass. The patient's serum alpha-fetoprotein (AFP) was 46.8 ng/ml (reference < 25 ng/ml). Fine-needle aspiration (FNA) of the mass revealed malignant glandular cells. Chemotherapy was instituted, followed by resection of the large abdominal mass. The tumor was grossly encapsulated, consisting of large areas of necrotic, hemorrhagic tissue surrounded by smaller, multiloculated cysts. Microscopically, the tumor had a villoglandular pattern and variably stratified tall columnar cells. A prominent feature of the columnar cells was supranuclear and subnuclear vacuolization. Intracytoplasmic PAS-positive, diastase-resistant hyaline globules were occasionally present. AFP by immunoperoxidase was prominent within the tumor. This recurrence of the previously diagnosed testicular teratoma with embryonal carcinoma represents a yolk sac tumor with components strongly resembling endometrioid carcinoma, a variant only recently described in eight cases of ovarian origin (Clement et al.: Am J Surg Pathol 1987; 11(10):767-778). We believe this is the first reported case of an endometrioid-like variant of testicular yolk sac tumor and also the first report of the FNA cytology findings in this variant.     

Alpha-fetoprotein localization in pure ovarian teratoma. An immunohistochemical study of 12 cases

Twelve cases of pure ovarian teratoma were studied by immunohistochemical methods to determine the incidence and localization of alpha-fetoprotein (AFP) production. There were six mature teratomas (grade 0) and six immature ones (grades 1-3). Three tumors (grades 1, 3, and 3 and stages III, I, and III, respectively) had isolated foci of AFP immunoreactivity in yolk-sac-like vesicles, intestinal-type epithelium, or tissue resembling liver, whereas the other nine tumors had no AFP-positive components. The former three patients had preoperative serum AFP determinations; the values were elevated in two of them, and in both instances the oncofetoantigen became undetectable one month after oophorectomy. Both patients are alive and well 15 and 25 months later; the third patient with a normal serum AFP before surgery and a positively stained tumor died of recurrent disease. The authors' findings indicate that the production of AFP in pure ovarian teratomas recapitulates its pattern of synthesis during ontogeny. Furthermore, it is suggested that a preoperative elevation of serum AFP in a pure ovarian teratoma does not seem to correlate with stage or grade, beyond minimizing the possibility that the tumor is grade 0, or mature.     

Microheterogeneity of Alpha-fetoprotein in Patient Serum as Demonstrated by Lectin Affino-electrophoresis

Microheterogeneity of alpha-fetoprotein (AFP) present in the sera of 76 patients was studied by lectin affino-immunoelectrophoresis. Seventeen patients had benign liver disorders and the remaining 59 patients were treated for primary or secondary liver cancer or yolk sac tumour. By means of Con A, AFP was divided into two variants, while lentil lectin (LCA) made it possible to separate AFP in three variants. In some patients the relative concentrations of Con A and LCA AFP variants were similar; these patients were believed to produce AFP of the same 'profile'. Fourteen AFP profiles were observed by estimation of the area enclosed by precipitates corresponding to respective AFP variants. It was also possible to estimate the AFP profile on the basis of a simple visual analysis of the electrophoretic plates. The obtained results indicate that the AFP profiles of patients with cancer were variable. In spite of variations of the AFP profile in cancer patients, in most cases it was possible to differentiate primary liver cancer from yolk sac tumour and from liver metastases of cancer. In addition, in two-thirds of hepatoma patients the AFP profile was different from the profile observed in patients with benign liver disorders.     

Characteristics of "embryoid body" in human gonadal germ cell tumors

The characteristics of so-called "embryoid body" appearing in gonadal germ cell tumors were studied histologically and immunohistochemically on serial sections of three cases (one ovary and two testes). The embryoid bodies were usually observed to be contiguous with immature or mature intestinal ducts, hepatic nests, or epidermal cell nests on serial sections, though they appeared to be isolated in one section. The "amniotic cavity"-like structure of embryoid body was continuous with intestinal duct, and rarely with squamous cell nests, while the "yolk sac" was continuous with hepatic tissue. In these immature or mature structures, differentiation was always found independently of "disc," and portions of "ectoderm" and "endoderm" remained less differentiated in comparison with others. These findings were in contrast with a normal embryo in which immature and/or mature structures are derived from the embryonic disc. The amniotic cavity connected frequently with yolk sac. From the present results, the embryoid body is not considered to be a real or teratomatous embryo, but only a product during a divergent differentiation into intestine and liver from the plastic epithelium, which seems to be derived from an embryonic gut.     

Analysis of ovarian teratomas for isochromosome 12p: evidence supporting a dual histogenetic pathway for teratomatous elements.

Teratomas are the most common germ cell tumor (GCT) of the ovary and include several types with a range of clinical behavior. As in testicular teratomas, they may be benign, malignant or a component of a mixed GCT. In the testis, data support separate pathogeneses for prepubertal and postpubertal teratomas, with derivation of the former from a nontransformed germ cell and the latter from differentiation of a nonteratomatous, malignant GCT. The absence of cytogenetic abnormalities (including isochromosome 12p (i(12p)) in mature ovarian teratomas suggests that they may be analogous to prepubertal testicular teratomas, but there are no data regarding genetic changes in the teratomatous components of ovarian mixed GCTs. We therefore studied the teratomatous components of six mixed GCTs of the ovary using fluorescence in situ hybridization (FISH) for i(12p). Six mixed GCTs of the ovary occurred in patients 4-33 years of age; all had teratomatous and yolk sac tumor components and three also contained foci of embryonal carcinoma. Using FISH with 12p telomeric and 12 centromeric probes, five of six (83%) cases had detectable i(12p) in their nonteratomatous components, and four of six (66%) in the teratomatous component. One of the two cases without demonstrable i(12p) in the teratomatous portion of the mixed GCT also did not have identifiable 12p abnormalities in other elements of the mixed GCT. By comparison, five pure, mature ovarian teratomas and three pure, immature ovarian teratomas showed no evidence of either i(12p) or other forms of 12p amplification. These findings support that teratoma in mixed ovarian GCTs has a different pathogenesis compared to pure teratoma of the ovary. Furthermore, the findings of i(12p) in both the teratomatous and nonteratomatous components of ovarian mixed GCTs supports that the teratoma derives from other components, similar to the situation in the testis.