Tumor Of Immature Cells Research Articles

The use of the monoclonal antibody Ki-67 in determination of the growth fraction in pediatric brain tumors

Using the monoclonal antibody Ki-67, proliferating cells were demonstrated immunohistochemically in 16 tumors of the nervous system in children, and these findings compared with those in 44 adult tumors. The antibody, which reacts with a nuclear protein expressed during the G1, S, G2, and M phases of the cell cycle, was demonstrated in frozen (13 cases) or smear (3 cases) sections using the peroxidase-antiperoxidase method. The percentage of stained tumor cells in children was in general agreement with the histological grade, ranging from 0.2% in a schwannoma to 12.4% in a juvenile type of glioblastoma. In a medulloblastoma, the fraction of labeled nuclei was 10.2%. In malignant gliomas of children, the percentage of stained cells did not differ from that in adult tumors. However, some cases demonstrated an unusually higher number of positive cells associated with higher cellularity than did adult tumors; this is in agreement with the content of small immature tumor cells in many pediatric tumors. The use of Ki-67 staining could become an important additional criterion for predicting the biologic behavior of nervous system neoplasms in children.

Histopathologic studies on adenocarcinoma of the parotid gland.

Of 683 cases of primary epithelial tumors arising in the parotid gland, 20 cases could be defined as adenocarcinomas, constituting 2.9% of the total number or 10.0% of 201 malignant tumors. These adenocarcinomas were characterized by a marked diversity in the histologic manifestations, presenting tubular, papillary, pseudoadenoid cystic, cribriform, trabecular, sarcomatoid, and other patterns. Basically, however, they could be classified into two major subtypes, i.e., tubular and papillary variants on the basis of their predominant histological patterns. The tumor cells showed a distinctive sign of high grade malignancy such as the occurrence of many mitotic figures and involvements of lymphatic vessels and/or blood vessels. Ultrastructurally, the tumor cells consisted of two basic varieties, resembling myoepithelial cells and duct epithelium. It is thus suggested that immature tumor cells could differentiate into a structure mimicking an intercalated duct. Clinicopathologically, the tumors were seen with a higher frequency in middle-aged males (average 44 years of age).

IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL STUDY ON ERYTHROPOIESIS IN HEPATOBLASTOMA

Eighteen cases of hepatocellular carcinoma in children were examined, and it was found that erythropoiesis exclusively appeared in the well differentiated type of hepatoblastoma. In such foci large immature erythroblasts were found among the tumor cells, whereas mature forms tended to gather in the subendothelial spaces or within sinusoids. Desmosome-like attachments were frequently found between immature erythroblasts and tumor cells. The tumor cells were well differentiated and had a distinct polarity. The erythropoietic foci were never found in lymph nodes, spleens and in the non-neoplastic hepatic tissues obtained by surgery or autopsy. Erythroblastic cells did not show an increase in number in the bone marrows. These findings indicate that hepatoblastoma cells in certain stages of differentiation have the capacity to induce the differentiation of pluripotent hemopoietic stem cells into the cells of erythrocytic series, or that the microenvironment composed of one or more tumor cells offer good soil for the differentiation of erythroblastic cells. There seems to be no intimate relationship between the production of alpha-fetoprotein by tumor cells and the appearance of erythropoiesis.

Distribution of Alpha-Fetoprotein and Immunoreactive Carcinoembryonic Antigen in Human Hepatocellular Carcinoma and Hepatoblastoma

The distribution of alpha-fetoprotein (AFP) and immunoreactive carcinoembryonic antigen (CEA) in 62 hepatocellular carcinomas (HCC) and five hepatoblastomas (HBL) all surgically removed was studied by an immunohistochemical method, and the results were compared with the levels of the antigens in the patients' serum. AFP was present as coarse granules in the cytoplasm of immature tumor cells. AFP-positive tumor cells were detected in 34/43 cases (79.1%) with serum AFP levels higher than 400 ng/ml and in 1/24 (4.2%) of the remaining cases. They were present in 8/32 (25%) cases of relatively well-differentiated HCC (Edmondson's grade I or II), 22/32 (68.8%) of relatively poorly differentiated HCC (Edmondson's grade III or IV), and 5/5 of HBL. An antigen immunoreactive with a conventional rabbit anti-CEA immunoglobulin (DAKO) but not with a murine monoclonal anti-CEA antibody (Hybritech) was present on the surface of bile canaliculi of both non-neoplastic and neoplastic hepatocytes. This CEA cross-reactive differentiation antigen was more often found in relatively well-differentiated tumors, and the presence of this antigen in tumors did not correlate with patients' serum CEA levels. In conclusion, CEA of an oncofetal nature was not produced by either HCC or HBL.

Cytological Findings of Neuroblastoma and Wilms' Tumor

The cytological examination of touch smears prepared from 3 patients with neuroblastoma, 2 with Wilms'tumor and 2 with pulmonary small cell carcinoma, were performed. The purpose of this paper is to know whether cytologically differential diagnosis of malignat tumors in childhood is possible or not. The specimens were stained by Papanicolaou's, May-Giemsa's and Giemsa's method. The findings of touch semears were compared with those of histological and electromicroscopic sections.Characteristics of neuroblastoma were as follows:1) Tumor cells were seen in a single and irregular clusters.A few rossete formation were found.2) Neuroblastoma cells were round or oval, almost naked, 8-22μ in size.3) Nuclei of neuroblastoma cells were composed of highly increased chromatin with fine granular structure, and some of them had small nucleoli.4) Electronic microscopy revealed that immature tumor cells were scanty cytoplasma with small numbers of organellas and moderately mature cells were abundant with many.Feature of these cells was characterized by the presence of numerous cytoplasmic processes excluding into the intercellular space. They contained numerous organellas and some neurosecretory granules.Wilms' tumor was as follows:1) Epithelial cell clusters and sarcomatous spindleshaped cells in irregularly-overlapping clusters were found.2) The nuclei of tumor cells were oval in shape, 9-22μ in size, and were composed of moderately increased chromatin with fine reticular pattern.3) Under electron microscopy, the cytoplasma was fround abundant with many organellas and the desmosome and pseudolumen between adjacent cells were found.Pulmonary small cell carcinoma was followings:1) The cytological findings were resemble to neuroblastoma in the point of the cell-arrangement and naked nucleus.2) Tumor cells were 9-19μ in size and nuclei were composed of severe increased chromatin with irregular nuclear membrane. But a quantity of chromatin among the tumor cells was different in Papanicolaous'stain.By the cytological findings described above, it was possible to distinguish neuroblastoma from Wilms'tumor and pulmonary small cell carcinoma in diagnostic cytology.

BK virus-induced experimental brain tumor.

The cytogenesis of BK virus-transformed hamster brain cells (HBBK cells) was studied. HBBK cells with indistinct processes showed a tendency to epithelial arrangement as well as characteristics of malignant or immature tumor cells in vitro. They developed long, delicate processes forming tree-like networks and were transformed into mature glia-like cells by the addition of c-AMP into the culture medium. Glial fibrillary acidic protein was demonstrated by immunofluorescent staining in the cytoplasm of almost all HBBK cells. The tumors arising in hamsters after subcutaneous inoculation of HBBK cells resembled human immature neuroectodermal tumors such as medulloblastoma, ependymoblastoma or glioblastoma, and were classified as poorly differentiated gliomas from their cytomorphological characteristics. This study suggested a selective transformation of glial cells in hamster brain cell cultures by BK virus or an affinity of BK virus for glial cells.

Malignant histiocytosis

Clinically, malignant histiocytosis is a malignant neoplasia with poor prognosis. Diseased are lymphnodes (especially cervical nodes), liver, spleen and bones. Few cases become leukemic. The cells show characteristic pale roundish, often indented nuclei, without large nucleoli and with abundant ill-defined cytoplasm. Phagocytosis of erythrocytes and leukocytes, as well as, hemosiderin deposits may serve as indicators for histiocytic, respectively macrophagic qualities. On touch preparation, tumor cells previously had been marked by acid phosphatase and non-spevific esterase, as being histiocytic. - A comparable marking could be carried out on paraffin embedded material with lysozyme (muramidase) and alpha1-antichymotrypsin, by the indirect immuno-peroxidase technique. No correlation could be proven between any special shape of tumor cells or between different grades of cellular atypism and presence or absence of the immunohistochemical reaction. The reaction with lysozyme and alpha1-antichymotrypsin was also tested in other tumors and was found to be positive in a variety of different tumor cells showing degenerative changes, respectively necrobiosis. - But lysozyme and alpha1-antichymotrypsin are markers characteristically found in histiocytes, respectively histiocytic tumor cells. They are apparently less distinct in MH with a larger number of immature histiocytic tumor cells.

Cytodiagnosis of Mediastinal Neuroblastoma

Preoperative cytological diagnosis is very important for the treatment of mediastinal neuroblastoma. Recently, cytological smears of mediastinal tumor can be obtained by percutaneous needle biopsy. The purpose of this paper is to know whether subtype of mediastinal neuroblastomas can be diagnosed or not. Findings of needle biopsy smears were compared with that of tumor stamps and histological sections.Cytological characteristics of these tumors are followings:1. Mature tumor ganglion cells were characterized by abundant, dark bluish cytoplasma which has brown pigment granules. The nuclei were single or several and nucleoli were enlarged.2. Small immature tumor cells were pleomorphic and almost naked. A few rossete formation were found.A ganglioneuroma consisted of mature ganglion tumor cells and a ganglioneuroblastoma had both mature and immature tumor cells, and many transistional type of these cells were found. In neuroblastoma smears, only immature tumor cells were found.It was concluded that ganglioneuroma, ganglioneuroblastoma and neuroblastoma could be diagnosed by characteristical findings of tumor cells obtained by percutaneous needle biopsy.