Synchronous ovarian dysgerminoma and breast carcinoma in a patient with positive immunostain of BRCA1

Breast cancer is the most common malignant neoplastic process and the second cause of death for women. Ovarian cancer, despite having a lower incidence, represents an important cause of morbidity and mortality because it is usually discovered in advanced stages. The presence of both forms of cancer in a patient is associated with a high risk of BRCA1 gene mutations, which are responsible, together with BRCA2 gene mutations, for most of the breast and ovarian cancer family. Our case is special because it presents a synchronous and a rare association of a primary ovarian dysgerminoma (with an incidence of less than 1% of ovarian cancers) and a primary breast carcinoma in a patient of 46 years old. Immunohistochemical examination was performed using a panel of five biomarkers: oestrogen receptor, progesterone receptor, Herceptest, p53 and BRCA1. In our case, we identified a negative hormonal status and the absence of HER2/neu expression but a positive immuno-expression for p53 protein and BRCA1 protein. Postoperative course was favourable for the patient after each surgery, and she was discharged with the recommendation to perform a genetic counselling.

Ovarian dysgerminomas are characterised by frequent KIT mutations and abundant expression of pluripotency markers

BACKGROUND

Ovarian germ cell tumours (OGCTs) typically arise in young females and their pathogenesis remains poorly understood. We investigated the origin of malignant OGCTs and underlying molecular events in the development of the various histological subtypes of this neoplasia.

RESULTS

We examined in situ expression of stem cell-related (NANOG, OCT-3/4, KIT, AP-2gamma) and germ cell-specific proteins (MAGE-A4, NY-ESO-1, TSPY) using a tissue microarray consisting of 60 OGCT tissue samples and eight ovarian small cell carcinoma samples. Developmental pattern of expression of NANOG, TSPY, NY-ESO-1 and MAGE-A4 was determined in foetal ovaries (gestational weeks 13-40). The molecular genetic part of our study included search for the presence of Y-chromosome material by fluorescence in situ hybridisation (FISH), and mutational analysis of the KIT oncogene (exon 17, codon 816), which is often mutated in testicular GCTs, in a subset of tumour DNA samples. We detected a high expression of transcription factors related to the embryonic stem cell-like pluripotency and undifferentiated state in OGCTs, but not in small cell carcinomas, supporting the view that the latter do not arise from a germ cell progenitor. Bilateral OGCTs expressed more stem cell markers than unilateral cases. However, KIT was mutated in 5/13 unilateral dysgerminomas, whereas all bilateral dysgerminomas (n = 4) and all other histological types (n = 22) showed a wild type sequence. Furthermore, tissue from five phenotypic female patients harbouring combined dysgerminoma/gonadoblastoma expressed TSPY and contained Y-chromosome material as confirmed by FISH.

CONCLUSION

This study provides new data supporting two distinct but overlapping pathways in OGCT development; one involving spontaneous KIT mutation(s) leading to increased survival and proliferation of undifferentiated oogonia, the other related to presence of Y chromosome material and ensuing gonadal dysgenesis in phenotypic females.

Expression of Claudins 1, 4, 5, and 7 in Ovarian Tumors of Diverse Types

In this study, 60 different types of ovarian lesions, mainly consisting of ovarian neoplasms, were studied for the expression of claudins 1, 4, 5, and 7. Strong expression of claudins 1, 4, and 7 was seen in benign and malignant epithelial ovarian tumors. Expression of claudin 5, reported to be mainly present in endothelial cells, was seen in ovarian epithelial tumors, but with a significantly lower frequency than claudins 1, 4, and 7. On the contrary, sex-cord stromal tumors and cysts, such as fibromas/thecomas, Sertoli-Leydig cell tumors, granulosa cell tumors, and follicular and luteinized cysts were mainly negative for claudins 1, 4, 5, and 7. Interestingly, adenomatoid tumors did not express claudin 5, which is in agreement with their non-endothelial nature. They were also negative for claudin 4, but expressed claudins 1 and 7, but to a lesser degree than epithelial lesions. In immature teratomas, the epithelial component was usually positive whereas other components were negative for these claudins. Dysgerminomas did not express any of the claudins studied. The results show that claudins 1, 4, and 7 are mainly expressed in ovarian epithelial tumors and can thus be used to indicate epithelial differentiation in them. Eventhough considered an endothelial marker, claudin 5 was also present in a subset of epithelial lesions. However, this claudin can be used to differentiate adenomatoid tumors from vascular lesions. No significant difference was seen between epithelial benign and malignant lesions, except for claudin 5, which seemed stronger in malignant epithelial tumors.

Increasing expression of extracellular matrix metalloprotease inducer in ovary tumors: tissue microarray analysis of immunostaining score with clinicopathological parameters

Ovary cancer invasion is responsible for both local tissue destruction and distant metastasis. Invasion is largely mediated by matrix metalloproteases that are thought to be induced by tumor cell-derived extracellular matrix metalloprotease inducer (EMMPRIN) in surrounding fibroblasts. We hypothesized that EMMPRIN isoverexpressed in ovary tumors. Immunohistochemical analysis of EMMPRIN was performed in tissue microarrays of ovary neoplasms including 84 cases of serous adenocarcinoma, 23 cases of mucinous adenocarcinoma, 10 cases of endometrioid adenocarcinoma, 12 cases of yolk sac tumor, 12 cases of clear cell carcinoma, 8 cases of dysgerminoma, 8 cases of granulosa cell tumor, 6 cases of transitional cell carcinoma, and 6 cases of Brenner tumor. All malignant ovary tumors showed significant immunohistochemical expression of EMMPRIN. The EMMPRIN scores in malignant ovary tumors were significantly higher than their nontumor counterparts (313+/-28 for serous adenocarcinoma; 308+/-25 for mucinous adenocarcinoma; 187+/-19 for endometrioid adenocarcinoma; 265+/-23 for yolk sac tumors; 87+/-13 for clear cellcarcinoma; 126+/-15 for dysgerminoma; 243+/-26 for granulosa cell tumor; 87+/-16 for transitional cell carcinoma). The EMMPRIN score was significantly higher in serous adenocarcinomas than in serous adenomas and serous borderline tumors and was correlated with nodal stage. Our findings show for the first time that EMMPRIN is overexpressed in all malignant ovary tumors.

A case of pediatric ovarian dysgerminoma associated with high serum levels and positive immunohistochemical staining of neuron-specific enolase

A 5-year-old girl presented with a painful abdominal mass. Abdominal magnetic resonance imaging (MRI) showed 3 separate masses. Tumor markers including lactate dehydrogenase (LDH), cancer antigen-125 (CA-125), beta-subunit of human chorionic gonadotropin (beta-hCG) and neuron-specific enolase (NSE) were elevated. At operation, the main tumor arose from the left ovary and was associated with torsion, whereas the other lesions were lymph node metastases. A salpingo-oophorectomy was performed. Histopathologic examination indicated that the tumor was a dysgerminoma. Immunohistochemicallly, the cells were positive for NSE and placental alkaline phosphatase (PALP) but were negative for CA-125, beta-hCG, S-100, glial fibrillary acidic protein, and vimentin. The elevated serum levels of tumor markers improved dramatically after the operation and chemotherapy.

Gonadal malignant germ cell tumors express immunoreactive inhibin/activin subunits

OBJECTIVE

Inhibin and activin are proteins produced by ovarian granulosa cells and testicular Sertoli cells and are members of the transforming growth factor-beta superfamily. Since increased circulating levels of immunoreactive inhibin were detected in women with malignant ovarian tumors, they were proposed as tumor markers for ovarian carcinoma. Immunohistochemical studies later confirmed the presence of inhibin and activin subunits in granulosa cell tumors and epithelial ovarian cancer, as well as in Sertoli and Leydig cell testicular cancer. However, there is discrepant information on the detection of inhibin and activin in malignant germ cell tumors (MGCT). The aim of the present study was to evaluate the immunohistochemical expression of the inhibin/activin alpha, betaA and betaB subunits in ovarian and testicular MGCT specimens using polyclonal antisera.

METHODS

The ovarian tissue samples were composed of 19 MGCT, including dysgerminoma (n=18) and yolk sac tumor (n=1). The testis specimens included classic seminomas (n=20), embryonal carcinomas (n=7), choriocarcinomas (n=2), and yolk sac tumor (n=1).

RESULTS

Ovarian and testicular malignant germ cell tumors expressed positive staining for inhibin/activin alpha, betaA and betaB subunits, with some variations between and within individual tumors: while ovarian dysgerminomas were diffusely positive for alpha, betaA and betaB, testicular tumors expressed alpha and betaB subunits, whereas betaA staining was weak.

CONCLUSIONS

The present results show positive staining for inhibin/activin subunits in ovarian and testicular MGCT, suggesting a possible role in tumorigenesis with the resultant clinical implication.

Dysgerminoma in a pure 45,X Turner syndrome: report of a case and review of the literature

There is a high risk of neoplasm in dysgenetic gonads. Classically, in Turner syndrome, only patients with 45, X/46, XY mosaicism karyotype or with a fragment of Y chromosome (45, X+mar) are at risk of developing gonadal tumor. A case of a dysgerminoma arisen on the dysgenetic gonad of a 45, X Turner patient in the absence of Y chromosome material at cytogenetic and molecular biology analysis is reported. Five cases of gonadal tumor with a pure 45, X chromosome constitution have been previously reported in the literature. In these cases only cytogenetic analysis was performed. This is the first case of an ovarian tumor in a 45, X Turner syndrome in which the presence of Y material can be ruled out by an extensive molecular analysis of the blood and the tumor.

Preferential localization of c-kit product in tissue mast cells, basal cells of skin, epithelial cells of breast, small cell lung carcinoma and seminoma/dysgerminoma in human: immunohistochemical study on formalin-fixed, paraffin-embedded tissues

Eighteen hundred and eighty-four cases of human solid tumours and 833 samples of normal human tissues, formalin-fixed and paraffin-embedded, were examined immunohistochemically for expression of c-kit oncogene product using polyclonal antibody against synthesized c-kit peptide. Seminoma/dysgerminoma and small cell lung carcinoma (SCLC) show preferential c-kit expression at 92% and 36% frequency, respectively, whereas only sporadic cases of cervical carcinoma and non-SCLC lung carcinoma show c-kit positivity. A normal tissue counterpart positive for c-kit product is detected in the testis (spermatocyte) and ovary (oocyte) but not in the lung or the cervix. In contrast, normal epithelial cells of the breast, skin basal cells and tissue mast cells harbour c-kit product, but transformed cells of the former two are largely deficient in the c-kit protein. One hundred and thirty-nine neuroendocrine tumours and 39 non-pulmonary small cell carcinomas were all negative, except for two cases of neuroblastoma. This indicates a distinct character for SCLC in c-kit expression. The c-kit product may be a useful marker in diagnostic pathology of seminoma/dysgerminoma and SCLC among human solid tumours, and in distinction of SCLC from non-pulmonary small cell carcinoma.

Frequent overexpression of p53 in dysgerminoma of the ovary

The expression of p53 in 7 dysgerminomas of the ovary was investigated immunohistochemically with the monoclonal antibodies DAKO-p53/Do-7 and Dianova-p53/Do-1. All the tumors exhibited overexpression of p53 protein. Immunoreactive tumor cell nuclei amounted to more than 50% in 2 tumors, 10-50% in 2 tumors, and less than 10% in 3 tumors. No relationship was found between tumor stage and the degree of p53 expression. Overexpression of p53 thus appears to be very common in dysgerminoma, as it is in epithelial ovarian cancer.

Analysis of a non-ras 21-kDa protein in patients with metastatic testicular germ-cell tumors

A novel protein of 21 kDa (p21) has been detected in the sera of patients with different solid tumors. The serum levels of this p21 protein were measured in seven patients with metastatic testicular germ-cell tumors before and after chemotherapy using an enzyme-linked immunosorbent assay. In five out of six patients who responded to chemotherapy a concomitant decrease of p21 serum levels was found. The decrease of p21 was in accordance with the decline of the established tumor markers alpha-fetoprotein, human chorionic gonadotropin beta-subunit and lactate dehydrogenase in three patients with non-seminomatous tumors and with the decline of lactate dehydrogenase and the clinical response in two patients with seminoma. In one patient the predicted decline of p21 did not occur despite the patient's clinical response to chemotherapy. In the seventh patient, who relapsed directly after chemotherapy, no decline of either p21 levels or tumor markers was observed. The absolute amount of the p21 protein prior to chemotherapy did not correlate with the patients' tumor burden. Elevated levels of p21 were found in patients with seminomatous and non-seminomatous germ-cell tumors. Since seminoma patients do not secrete tumor markers like alpha-fetoprotein or human chorionic gonadotropin beta, the determination of p21 levels may help to evaluate the efficacy of chemotherapy in patients with seminomatous as well as in patients with marker-negative non-seminomatous germ-cell tumors. The biological role of p21 and its clinical significance will be further investigated.

Immunohistochemical expression of embryonal marker TRA-1-60 in carcinoma in situ and germ cell tumors of the testis

BACKGROUND

Testicular cancer is preceded by the noninvasive stage of carcinoma in situ (CIS). According to a recent hypothesis, testicular CIA cells are germ cells transformed in fetal life. The idea of an embryonal origin of testicular germ cell neoplasia would be strengthened by the finding of antigenic similarity between fetal germ cells, CIS cells, and invasive testicular germ cell tumors.

METHODS

Monoclonal antibody (MoAb) TRA-1-60 raised against a human embryonal carcinoma cell line was immunohistochemically tested on 21 fetal gonads (11 male gonads and 10 female gonads; 11th-24th week of gestation). In addition, TRA-1-60 was tested on tissue from 27 testes with CIS, 11 testes with invasive testicular cancer, and 24 adult and 4 infant testicular control specimens.

RESULTS

Expression of TRA-1-60 was found in germ cells of six female and two male fetal gonads. In addition, 26 of 27 adult human testes with CIS, 7 of 8 seminomas, and 3 of 3 embryonal carcinomas were TRA-1-60 positive.

CONCLUSIONS

The study demonstrated an antigenic link between fetal germ cells, cells of CIS and seminomas, and embryonal carcinomas. The results provided additional evidence for the hypothesis that testicular neoplasia arises during early fetal life and CIS cells are malignant fetal gonocytes.

Immunohistochemical detection of intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex class I antigens in seminoma

Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex (MHC) antigens, and characterization of tumor-infiltrating mononuclear cells (TIM) were examined immunohistologically in 10 specimens of seminoma. ICAM-1 and MHC antigens were not detected on normal spermatogenic cells. ICAM-1 and MHC class I antigens were variably expressed in 7 and 9 seminomas, respectively, whereas class II antigens were not detected. Although the degree of expression of ICAM-1 and MHC antigens was not correlated with any clinical or histopathological factors, neither of the antigens was detected on an anaplastic seminoma. Various numbers of TIM were detected in all of the seminoma, and comprised mainly T cells bearing the lymphocyte function-associated antigen (LFA)-1. No significant correlation was noticed between the degree of lymphocyte infiltration and ICAM-1 or MHC antigen expression. Although ICAM-1 and MHC class I antigens were expressed in seminoma, possibly facilitating an anti-tumor reaction of host, their expression remained low in several cases, despite marked lymphocyte infiltration within the tumor.

Expression of c-kit receptor in normal and transformed human nonlymphoid tissues

The protooncogene c-kit encodes a tyrosine kinase with a molecular weight of 145,000, highly related to the platelet derived growth factor/colony stimulating factor receptors. Mutations of the murine gene result in impairment of hematopoiesis, gametogenesis, and of the melanocyte cell lineage. In order to elucidate c-kit functions in development and oncogenesis we have analyzed immunohistochemically its expression in human normal and transformed nonlymphoid tissues. The receptor has been detected in spermatogonia, melanocytes, and unexpectedly, in astrocytes, renal tubules, parotid cells, thyrocytes, and breast epithelium. While the gene product is expressed in seminoma, lung tumors, and melanoma of low invasiveness, no detectable levels have been detected in thyroid and breast carcinomas, astrocytomas, and invasive melanomas. In breast tumors these findings were confirmed by paired, Northern blot analysis of RNA preparations from normal and transformed tissue. The present results demonstrate that the c-kit receptor plays a role in the development of a larger spectrum of cell lineages. Furthermore, on the basis of the transformation associated changes, we speculate that, while in some cell types, c-kit expression positively regulates mitogenesis and is selected for in neoplastic transformation, in other tissues the c-kit pathway is involved in morphogenesis and differentiation and is, therefore, negatively selected in the course of tumor progression.

Immunohistochemical identification of androgen receptors in germ cell neoplasia

The highest prevalence of testicular cancer occurs in young men with high androgen activity. The presence and distribution of androgen receptors (ARs) was therefore investigated in germ cell neoplasia, using two specific monoclonal antibodies. Tissue samples from 18 patients with seminoma and/or carcinoma-in-situ (CIS) of the testis were examined. An indirect immunohistochemical method with a biotin-streptavidin-peroxidase or an alkaline phosphatase detection system was used. 45% of seminoma samples and 42% of CIS samples were AR-positive with antibody AN 1-15. The values obtained using antibody F 39.4.1 were 44 and 40% respectively. Some differences in specificity between the two antibodies were observed. Unusual granular staining of germ cells in normal testes, also present in malignant germ cells, was noted when antibody F39.4.1 was used. The presence of AR protein immunoreactivity in neoplastic germ cells suggests that androgens may be involved in the pathogenesis of the disease.

Immunohistological analysis of tumour infiltrating lymphocytes in seminoma using monoclonal antibodies

Immunological characterization of tumour infiltrating lymphocytes (TIL) by immunohistological techniques was carried out in 20 cases of stage I seminoma. Routine pathological examination of these surgical specimens showed typical seminoma in 20 cases. Eighteen cases showed obvious TIL and immunohistological staining on frozen specimens was performed in 12. TIL in seminomas were predominantly T-cells but B-cells were also identified. T-cells were distributed diffusely with predominance of the CD8+ phenotype judged semiquantitatively. In contrast to the distribution of T-cells, B-cells tended to accumulate and occasionally formed lymphoid follicles. In such follicles the phenotypic pattern of B-cell antigens was comparable with secondary lymphoid follicles in lymphoid organs. There is an immunologically complex response to seminoma by the host with a predominant infiltration of cytotoxic/suppressor T-cells and functional maturation of B-cells.

Globotriaosyl ceramide glycolipid in seminoma: its clinicopathological importance in differentiation from testicular malignant lymphoma

Glycolipids were biochemically extracted from 14 specimens of seminoma, 2 of testicular malignant lymphoma (both of which were difficult to differentiate from seminoma with a high mitotic index) and 4 of normal testicle. The pattern of their expression was compared. Marked accumulation of globotriaosyl ceramide was observed in seminoma but it was present in a small amount in testicular malignant lymphoma. Differentiation between seminoma and malignant lymphoma is sometimes difficult by histopathological findings but it is considered to be greatly facilitated by examination of the pattern of glycolipid expression.

Evidence for the transformation of seminoma to yolk sac tumor, with histogenetic considerations

Recent ultrastructural, cytogenetic, and ploidy analyses indicate that seminoma acts as a precursor from which other forms of testicular germ cell tumor may originate. Ten cases of primary or metastatic testicular germ cell tumors were investigated that showed possible transformation of seminoma to yolk sac tumor. Such transformation was identified in six cases in which foci of abrupt change from seminoma to various patterns of yolk sac tumor occurred, often at the periphery of otherwise pure lobules of seminoma. Immunostains for cytokeratins, placental-like alkaline phosphatase, and alpha-fetoprotein demonstrated the expected changes in reactivity at the foci of such transformation. Four additional cases were regarded as either seminomas with artifactual microcystic change or the close association of seminoma and yolk sac tumor but lacking evidence for transformation. These data support the theory that seminoma is not an "endpoint" neoplasm but may serve a precursor role in the progression to nonseminomatous germ cell tumors.

Placental-like alkaline phosphatase and DNA flow cytometry in spermatocytic seminoma

Immunohistochemical analysis was done on 7 testicular tumors classified as spermatocytic seminoma (SS) and 25 classic seminomas. Except for a few scattered cells, the spermatocytic seminomas were negative for placental-like alkaline phosphatase (PLAP); the classic seminomas were all positive for this enzyme. The SS also were negative for alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (hCG), and leukocyte common antigen (LCA). The ploidy of the seven tumors of SS was as follows: two, diploid; two, near-diploid; one, tetraploid; one, aneuploid; and one, uninterpretable. The essentially negative staining of SS for PLAP was strikingly different from the pattern in classic seminoma. Thus, staining for this enzyme is useful for making the differential diagnosis between classic seminoma and SS. To differentiate between malignant lymphoma and SS, staining for leukocyte common antigen is helpful.

Current status of tumor markers in testicular cancer. A practical review

Detection of serum and cellular AFP and hCG has made a significant contribution in understanding and management of testicular cancer. It is essential to remember the following events in utilizing these markers: (1) Histologic diagnosis of seminoma, but AFP is elevated. There is usually an element of choriocarcinoma. (2) Histologic diagnosis of seminoma and highly elevated hCG greater than 100 ng/ml has usually an element of choriocarcinoma. (3) Histologic diagnosis of choriocarcinoma with an elevated serum AFP. There is usually an element of embryonal carcinoma. (4) Pathologic stage I nonseminomatous testicular cancer with elevated serum markers is either stage II or stage III. (5) In a recent study of 23 patients undergoing resection of residual nonseminomatous testicular cancer after intensive chemotherapy, 21 had either teratoma in primary tumor or bulky metastatic disease. The markers were normalized after chemotherapy and prior to resection. (6) Although normalization of these markers after chemotherapy indicates effective therapeutic response, one should look of residual tumor utilizing radiologic investigations.

Morphology and immunohistochemistry of carcinoma in situ adjacent to testicular germ cell tumours in adults and children: implications for histogenesis

Observations differ on the pre-invasive malignant lesions associated with the various categories of testicular germ cell tumours. Such lesions have been found to be similar in appearance and are assumed to be composed of multipotent cells, or conversely a distinctive pre-invasive stage has been reported in association with each form of germ cell neoplasm. This study was undertaken to see whether distinctive morphological and immunohistochemical features of carcinoma in situ adjacent to various categories of germ cell tumours could be established. Carcinoma in situ adjacent to seminomas, teratomas and mixed germ cell tumours in 18 adults was indistinguishable morphologically. Placental alkaline phosphatase was demonstrated immunohistochemically but vimentin and low molecular weight cytokeratins were uniformly absent in these abnormal germ cells from all three groups. These findings support the concept of a multipotent pre-invasive malignant cell for both seminoma and teratoma in the adult. Carcinoma in situ was not seen adjacent to 15 spermatocytic seminomas, nor was placental alkaline phosphatase demonstrated in tubules adjacent to these tumours. These negative findings are additional evidence that spermatocytic seminoma differs from classical seminoma in its histogenesis. Carcinoma in situ, as defined morphologically and immunohistochemically in adults, was not identified adjacent to yolk sac tumours and differentiated teratomas in 20 prepubertal testes. The possibility that pre-invasive malignancy in children may not resemble that in adults must be considered when assessing the malignant potential of cryptorchid testes on biopsies taken during orchidopexy.

p53 protein alterations in human testicular cancer including pre-invasive intratubular germ-cell neoplasia

Expression of the p53 oncoprotein was examined in a wide range of primary human testicular germ-cell tumours using a new mouse monoclonal antibody (MAb) BP53-11 raised and characterized in this study, in parallel with a polyclonal rabbit antiserum CM-1. Immunohistochemistry on paraffin sections showed positive nuclear reaction in at least a fraction of malignant cells in 90 (84%) out of 107 cases studied. Aberrant accumulation of the p53 protein was found among testicular tumours of all major histological types, although generally a higher percentage of positive cases and a higher proportion of p53 over-expressing nuclei within individual lesions was observed in embryonal carcinomas when compared with seminomas. The typical heterogeneous staining pattern characteristic of histological specimens was also found in a cultured cell line derived from a human embryonal carcinoma. In contrast to immunohistochemically undetectable levels in normal testes and morphologically normal tissue areas in the tumour-bearing testes, the accumulation of the p53 protein was clearly identified in a high proportion (59% of cases) of the pre-invasive lesions with positive atypical intratubular germ cells often found in the tissue adjacent to invasive tumours. Altered expression of the p53 protein is therefore a unifying feature of the majority of invasive male germ-cell tumours and the change resulting in high levels of p53 appears to be a relatively early step in the human testicular cancer pathogenesis.

[Analysis of ferritin immunostaining in testicular tumors]

Localization of ferritin in testicular tumors was studied by the immunohistochemical method and the usefulness of ferritin was evaluated compared with the clinical course. Seven cases of seminoma and 9 cases of non-seminoma were used for the study. Formalin-fixed, paraffin-embedded tissue sections were stained by the avidin-biotin complex method. Commercial rabbit anti-human ferritin polyclonal antibody in 1/100 dilution was allowed to react at room temperature for one hour. In normal testicular tissues, the epithelium in germinal cells was not stained for ferritin. In seminomas, some tumor nests were stained for ferritin. Interstitial cells, especially histiocytes, were also stained for ferritin. In stained tumor cells, cytoplasm was stained uniformly. Necrotic cells were not stained. The same findings were obtained in non-seminomas. In metastatic lesions and tumor thrombi in the vessels, some tumor cells were stained as intensely as in the origin. A case was calculated positive if more than 5% of the tumor cells in the specimen were stained. The positive rate in ferritin immunostaining was significantly higher than that of human chorionic gonadotropin (beta-HCG), alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) immunostaining with the same materials. The specimens from cases with abnormally high serum ferritin level, were stained more intensely than those from cases with normal serum ferritin level. The result suggests that ferritin might be a useful tumor marker in some of testicular tumors.

[Flow cytometric analysis of DNA content in testicular seminomas--correlation to mitotic count]

The DNA ploidy of testicular seminomas was studied by flow cytometry using paraffin embedded samples. The mitotic count and DNA index (DI) for 27 seminomas were analyzed in 80 samples with a mean of 3.0 samples per case. Six anaplastic seminomas which were with 3 or more mitoses per a high power field were distinguished from 21 typical seminomas. DNA ploidy pattern was aneuploid in all seminomas except one case of anaplastic seminoma, and clonal heterogeneity in DNA content was found in 3 of 20 (15%) cases of which 2 or more samples were analyzed. Although the DI had no significant difference between those two groups of seminomas classified by mitotic count, the DI in anaplastic seminomas was ranged from 1.5 to 2.0 (median DI = 1.70), otherwise the DI in typical seminomas ranged from 1.5 to 3.5 (median DI = 1.89), particularly 9 cases in 21 (43%) typical seminomas distributed in hypertetraploid region. The median DI of stage I seminomas was 1.88 and that of stages II + III seminomas was 1.75, though there was also no significant correlation between DI and clinical stages. In general, it is postulated that the higher DI is paralleled to the more malignant nature of neoplasms, nevertheless this study suggested that the higher DI in seminomas is not always related to high malignant potentiality determined by histological type and clinical stage.

Immunohistochemistry of markers of histiomonocytic cells in malignant fibrous histiocytomas. A monoclonal antibody study

Nine cases of malignant fibrous histiocytomas (MFH) were examined immunohistochemically in frozen sections with six different monoclonal antibodies to histiomonocytic and related cells (EBM11, HAM-56, KB90, antibodies to dendritic reticulum cells, HLADR and LCA). Ten other soft tissue sarcomas, two desmoid tumors, twelve carcinomas, three seminomas and four lymphomas were studied for comparison. All cases of MFH showed positivity for histiomonocytic cell antigens. In six cases, the positive cells could be clearly interpreted to be infiltrating non-neoplastic cells. However, immunoreactivity for multiple histiocytic markers (EBM11, HAM-56, KB90, HLADR) was seen in tumor cells in three cases of MFH. In one of these cases, the positivity could be verified with KP1, an antibody to histiomonocytic cells applied in formalin fixed and paraffin embedded tissue. None of the tumors was positive with the antibody to dendritic reticulum cells or LCA. In the series of non-histiocytic tumors, no cases showed widespread positivity for multiple histiocytic markers. Our results suggest that in relation to true histiomonocytic differentiation MFH might be a heterogeneous group of tumors. The widespread immunoreactivity for multiple histiocytic markers in some cases may indicate a true histiomonocytic differentiation in some MFHs.

Heterogeneity of intermediate filament expression in human testicular seminomas

Testicular seminoma has in the past been considered to represent a germ cell tumor incapable of further differentiation. In recent years this view has been challenged on the basis of morphologic and chromosomal studies. Moreover, studies of intermediate filaments (IF) of seminoma cells have provided evidence of the capability of seminoma cells to differentiate in different directions. In the present study of the IF protein profile of 26 human testicular seminomas, using frozen as well as formalin-fixed, paraffin-embedded tissues, we report evidence of a heterogeneous differentiation potential inherent in these neoplasms. Thus, in 4 of the seminomas neither cytokeratins nor vimentin were detected; 3 showed vimentin positive cells but no cytokeratins; in 4 seminomas only cytokeratins were detected. In the remaining 15 cases both cytokeratins and vimentin were present, with occasional cells demonstrating coexpression of cytokeratin and vimentin. While the cytokeratins present were mostly of the "simple epithelial type", in 2 instances seminoma cells also contained cytokeratins 4 and 17, normally found in stratified and/or complex glandular epithelia. Furthermore, in 3 cases scattered tumor cells stained for desmin and in 2 other seminomas neurofilaments were identified. All of the cases showed variable positive staining for desmoplakins and desmoglein, indicative of the presence of desmosomes. It can therefore be concluded that, while some seminomas seem to be devoid of IFs, most of them show varied differentiation patterns usually with epithelial features but occasionally also with components commonly regarded as characteristic of myogenic or neurogenic differentiation. These observations may help to elucidate the relationship of seminomas to other germ cell tumors, and also contribute to our understanding of the histogenesis of these neoplasms.