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F A Tavassoli

Publications and source records attributed to F A Tavassoli.

At least 19 recordsLinked to original sources
PubMed2005

Remarkably high frequency of EGFR expression in breast carcinomas with squamous differentiation.

The human epidermal growth factor receptor (EGFR) is reportedly overexpressed in 15-20% of breast carcinomas. EGFR overexpression is associated with reduced survival and is inversely correlated with expression of estrogen receptor (ER). This study assessed EGFR expression in breast carcinomas with squamous differentiation. The immunohistochemical (IHC) expression of EGFR was evaluated in 39 breast carcinomas with squamous differentiation (30 pure squamous, 6 adenosquamous, 3 carcinosarcomas) by use of the pharmDx assay (clone 2-18C9, DakoCytomation). Cases were considered positive if at least 10% of the cells showed 1+ positivity in the squamous component. Squamous differentiation was confirmed with IHC for CK5-6 (clone D5/16B4, DakoCytomation). ER, PR, and HER2 status as well as clinical information regarding treatment and outcome were correlated. As a control, a tissue microarray comprising 280 lymph node positive breast carcinomas was evaluated with the same EGFR assay. The 39 patients ranged in age from 33 to 77 years (mean 52). The tumors measured 1.3-30 cm (mean 4.8). Sentinel or full axillary lymph node dissection was performed in 28 patients. Fourteen patients had positive lymph nodes. At the time of initial diagnosis, 3 patients had distant metastasis. Follow-up was available for 16 patients (mean 45 months). Disease-free survival at 3 years was 70%. Among the 39 tumors 87% (34) were positive for EGFR (p<0.0001). Sixty-nine percent (27 of 39) showed >50% 2+ EGFR staining. EGFR-positive tumor cells (showing squamous morphology) were also found in 1 bone, 1 lung, and 8 of 11 lymph node metastases available for evaluation. All 11 lymph nodes showed squamous differentiation. All but 1 of the EGFR+ tumors examined were ER and PR negative. Six EGFR-positive tumors were HER2 positive. No statistically significant differences in HER2 status, size, lymph node status and disease-free survival were observed between EGFR+ and EGFR- cases, but the number of EGFR-negative tumors was quite small. Nine of 280 (3%) of lymph node-positive invasive carcinomas on the tissue microarray were EGFR+; review of the initial diagnostic slides failed to reveal squamous features in all but 1 of the 9 EGFR+ tumors. Breast carcinomas with squamous differentiation are a distinct subgroup of breast tumors with a very high frequency of EGFR positivity. Breast carcinomas of this type would be ideal candidates for a trial with EGFR inhibitors.

Adult↗
PubMed2003

Central atypical papillomas of the breast: a clinicopathological study of 119 cases.

The clinicopathological features of central intraductal papillomas of the breast presenting with florid usual ductal hyperplasia or atypical ductal hyperplasia (ADH) were analyzed in a retrospective series of 119 patients, whose lesions were sent to the Armed Forces Institute of Pathology from 1976 to 1990. After histological review considering predefined morphological and quantitative criteria, the 119 central papillomas were classified into 22 papillomas with florid usual ductal hyperplasia (18%), 40 papillomas with focal atypia (34%), 24 atypical papillomas (20%) and 33 carcinomas arising in a papilloma (28%). After a median period of follow-up of 110 months, 16 recurrences (5 papillomas, 2 carcinomas arising in a papilloma, 4 ductal carcinomas in situ, 5 invasive carcinomas) occurred. No statistically significant difference was observed in relation to recurrence for the various categories of papillomas. The presence of epithelial hyperplasia, ADH or lobular neoplasia in the surrounding breast as well as infarction of the papilloma were significant predictive factors of recurrence ( P=0.02 and P=0.005, respectively, log-rank test). The main reason for the observed low rate of significant recurrences in this series was that epithelial atypia (whether comprising 20% or 60% of the papillary lesion) was, in most of the cases, localized in a confined lesion that was completely excised.

Adult↗
PubMed2003

Metastases to the breast.

AIM: The aim of this study was to report the clinico-pathological features of a series of patients with metastatic neoplasms to the breast. METHODS: A 10-year archive of surgical material was reviewed. A search was performed on all 10,650 breast neoplastic cases in the files of the Pathology Department from 1990 to 2000. RESULTS: There were 22 women and two men. The most common primary sites for solid tumours were cutaneous melanoma and ovarian carcinoma. Two of the 24 patients had no prior history of malignant disease. There was a solitary nodule in 17 cases; in seven cases there were multiple lesions in the same breast. Sixteen patients had a rapidly fulminating course and died of disease. Six patients are alive with disease and two patients were lost to follow-up. CONCLUSION: Recognition of these lesions as being metastatic may pre-empt radical surgery.

Adult↗
PubMed2003

Papillary endothelial hyperplasia of the breast: the great impostor for angiosarcoma: a clinicopathologic review of 17 cases.

Seventeen cases of papillary endothelial hyperplasia (PEH, Masson's vegetant intravascular hemangioendothelioma) involving breast or mammary subcutaneous tissues are described. The mean patient age was 59; 14 (82%) were female and 12 (71%) presented with a mass. Nine women had mammographic evaluation, 3 of whom had microcalcifications. Five neoplasms were discovered by routine mammography. Sixteen cases were 2.7 cm or less in greatest dimension, and 8 (47%) were associated with a thrombus and/or cavernous hemangioma. Follow-up in 10 cases (up to nearly 8 years) showed no recurrences. Fifty-nine percent of the cases were received at AFIP for consultation with a working diagnosis of angiosarcoma. Features that help distinguish PEH from angiosarcoma include circumscription of the lesion, location in a vessel or association with thrombus, and papillary architecture without significant cytologic atypia or areas of solid growth. The recognition of the morphologic features of this lesion and its inclusion in the differential diagnosis of vascular mammary tumors will reduce the likelihood of its misdiagnosis as an angiosarcoma and avoid unnecessary and aggressive therapy.

Adolescent↗
PubMed2002

Retiform Sertoli-Leydig cell tumours: clinical, morphological and immunohistochemical findings.

AIMS: To determine the morphological and immunohistochemical profile of retiform Sertoli-Leydig cell tumours and to compare the observed profile with that of adult rete ovarii. METHODS AND RESULTS: Nineteen retiform Sertoli-Leydig cell tumours were studied, eight by immunohistochemistry, and five examples of rete ovarii from adult females were also evaluated immunohistochemically. The patients ranged in age from 3 to 74 years with a mean age of 31 years. Four patients were virilized and had an abdominal mass; two were virilized with amenorrhoea and two had amenorrhoea alone. Eight presented with an abdominal mass and one patient was pregnant. Two tumours were incidental findings. Information on stage was available in 16 patients: 14 tumours were stage 1, one was stage 2, and one was stage 3. Fifteen tumours were of intermediate differentiation and four were poorly differentiated. Papillary structures were evident grossly in four cases. Microscopically, all cases had a retiform pattern in addition to varying quantities of sex cord, gonadal stromal and heterologous elements. Heterologous elements were present in 13 cases and consisted of hepatocytes (n = 7), mucinous epithelium (n = 7) and skeletal muscle (n = 2). Immunohistochemical evaluation of eight tumours showed a more intense positivity for keratin in the retiform areas, whereas the gonadal stromal component had a more intense expression of inhibin. Inhibin stains Leydig cells strongly and hepatocytes moderately. Rete ovarii epithelium was positive for keratin and vimentin in the five cases studied, and for inhibin in one case. Follow-up was available on 13 patients. Three tumours behaved in a malignant fashion: one each was stage 1, 2, and 3 at diagnosis. CONCLUSIONS: Immunohistochemistry is useful in distinguishing retiform Sertoli-Leydig cell tumours from other tumours that they may resemble. Inclusion of inhibin is essential in a panel of antibodies to evaluate these tumours. The clinical behaviour of these neoplasms cannot always be predicted from their morphology or clinical stage.

Adolescent↗
PubMed2001

Multiple use of slab gels in sequencing apparatus for separation of polymerase chain reaction products.

Attempting to assess whether a decrease of the electrophoresis temperature could prevent or reduce the extent of gel well deformations, and whether the utilization of native polyacrylamide gels (without urea) could speed up the separation of polymerase chain reaction (PCR)-amplified products with an automated 377 DNA sequencer, denatured PCR products were subjected to electrophoresis in 6% native gels under 45 degrees C. Results show that a decrease of the electrophoresis temperature from 51 degrees C (recommended by the User's Manual) to 45 degrees C substantially facilitates the preservation of gel wells, and that all PCR products tested migrate significantly faster in native than in denatured (with urea) gels of the same concentration. The combination of a 6% native gel and a lower (45 degrees C) electrophoresis temperature permits multiple uses of a given gel with consistent results, consequently reducing the electrophoresis time and reagent costs.

DNA↗
PubMed2001

Spindle cell ductal carcinoma in situ. An unusual variant of ductal intra-epithelial neoplasia that simulates ductal hyperplasia or a myoepithelial proliferation.

Seventeen examples of a variant of ductal carcinoma in situ (DCIS) composed exclusively or predominantly of spindle cells arranged in fascicles, whorls, and solid sheets are described. The fascicular arrangement of the spindle cells simulates the "streaming" phenomenon associated with ordinary intraductal epithelial hyperplasia (IDH). This process also resembles the myoid, solid form of intraductal myoepithelial proliferation. The women ranged in age from 38 years to 79 years with a mean age of 59.3 years. Five patients presented with a palpable mass. The remaining tumors were discovered using mammography. The radiological appearances of the lesions raised concern for carcinoma, but there were no distinctive mammographic findings to suggest an unusual variant of DCIS. Cytological preparations were suspicious for malignancy in two patients and were reported as malignant in another case. Sixteen patients were treated with wide local excision, and one woman had a partial mastectomy. The tumors measured from 3 mm to 15 mm (mean 8.65 mm). In three cases, minute foci of stromal invasion were associated with the spindle cell DCIS. In another specimen, a 2.7-cm invasive ductal carcinoma of no special type was identified in an area away from the foci of the spindle cell DCIS. None of the patients has experienced recurrence or metastasis during the relatively short mean follow-up period of 16.2 months (range 4-77 months). Spindle cell DCIS is distinguished from the streaming pattern of ordinary IDH by its solid growth pattern, lack of secondary spaces or peripheral fenestrations, uniformity of appearance and distribution of nuclei, cytological atypia in the range of low to intermediate-grade DCIS, and negative immunoreaction with CK-34betaE12 (HMW-CK903). When fenestrations are present, they are evident in areas of cribriform DCIS that merge with the solid, spindle cell areas in hybrid ducts harboring both patterns. This admixture, with conventional cribriform DCIS, and the association with foci of invasive ductal carcinoma in some cases further help recognition and confirmation of this lesion as in situ carcinoma. When there is no transition from the spindle cells to recognizable cribriform DCIS, distinction from intraductal myoepithelial hyperplasia (myoepitheliosis) requires immunostains for actin and S-100 protein. Recognition of this pattern of DCIS is important in order to avoid its frequent misclassification as a benign lesion.

Adult↗
PubMed2001

Superficial cervicovaginal myofibroblastoma: fourteen cases of a distinctive mesenchymal tumor arising from the specialized subepithelial stroma of the lower female genital tract.

The clinicopathologic features and immunohistochemical profiles of 14 cases of a distinctive mesenchymal tumor that arises in the superficial lamina propria of the cervix and vagina and is histologically distinguishable from mesodermal (fibroepithelial) stromal polyp, including the cellular (pseudosarcomatous) variant, angiomyofibroblastoma, aggressive angiomyxoma, and other well-recognized lesions that occur in this location, are described. The lesions presented as a polypoid (n = 10) or nodular (n = 4) mass in the vagina (n = 12) or cervix (n = 2) of women ranging in age from 40 to 74 years (median, 58 years). The tumors were subepithelial in location, were well circumscribed, and ranged in size from 1 to 6.5 cm. (mean, 2.7 cm). Microscopically, the process was moderately to highly cellular and composed of relatively bland spindled and stellate-shaped mesenchymal cells embedded in a finely collagenous stroma that was punctuated by myxoid and edematous foci in 9 cases. The lesions characteristically had a multipatterned architecture with tumor cells focally assuming a lacelike/sievelike growth pattern in the more stroma-rich areas of the tumor and a vague fascicular growth pattern in the more cellular foci. Mitotic activity was minimal, and no atypical mitotic figures were identified. The tumors were immunoreactive (in decreasing order of relative strength) for vimentin (5 of 5 cases), estrogen (10 of 10 cases), and progesterone (10 of 10 cases) receptors, desmin (13 of 13 cases), CD34 (11 of 13 cases), alpha-smooth muscle actin (5 of 11 cases), and muscle-specific actin (2 of 8 cases). The desmin and CD34 antibodies highlighted the interconnecting, dendritic processes associated with many of the tumor cells. No immunoreactivity was detected for S100 protein, epithelial membrane antigen, or keratins. Follow-up data for 11 patients (range, 1 to 20 years; median, 4 years) showed no recurrence or metastasis after local excision. The term "superficial cervicovaginal myofibroblastoma" is proposed because it reflects the distinguishing features of this benign, relatively site-specific mesenchymal tumor. The process probably arises as a neoplastic proliferation of hormonally responsive mesenchymal cells native to the unique subepithelial stromal layer normally found through the endocervix and vulva of adult women.

Adult↗
PubMed2001

An improved method for DNA extraction from paraffin sections.

The acquisition of comparable quality and quantity of DNA extracts is the prerequisite to the success of comparative genetic analyses. Although several DNA extracting protocols on paraffin sections have been introduced, the importance of deparaffinization, the procedure for obtaining an adequate hematoxylin staining, the significance of the ratio of the cell number to the enzyme volume, and a practical means for monitoring the digestion process have not been sufficiently addressed. These, however, are the most important factors accountable for a failure of DNA extraction. To minimize the impact of these factors, we have developed several unique strategies, including: (1) incubating sections at 80 degrees C for 30-60 minutes prior to xylene treatment, (2) checking each section to insure the complete removal of paraffin; (3) treating hematoxylin stained sections or cells with de-staining solutions; (4) using a micrometer inserted into the eyepiece of a microscope to estimate the number of cells collected and adjusting the enzyme volume according to the cell number; and (5) monitoring the digestion process with a magnifier. With these strategies, we have been able to consistently obtain comparable quality and quantity of DNA extracts which yielded uniform PCR products regardless of variations in tissue embedding and processing.

Clone Cells↗
PubMed2001

Mesonephric adenocarcinomas of the uterine cervix: a study of 11 cases with immunohistochemical findings.

Mesonephric adenocarcinoma is a rare variant of cervical carcinoma with relatively few, well-documented cases reported. We describe the clinicopathologic and immunohistochemical features of 11 examples of this neoplasm, which occurred in women between the ages of 35 and 72 years (mean, 52 years). Most (64%) patients had abnormal vaginal bleeding. Eight tumors were stage IB, and one each was stage IIB and IVB; in one, the stage was unknown. Microscopically, the carcinomas showed various morphologies, most commonly a small tubular pattern or a ductal pattern resembling endometrioid adenocarcinoma; one tumor had an associated malignant spindle cell component. Ten neoplasms were adjacent to hyperplastic mesonephric remnants. Follow-up in 10 cases showed six patients to be alive without evidence of recurrence after a mean of 4.8 years. The patients with stage IIB and IVB disease had local recurrences after 2.2 and 0.7 years and died of progressive disease at 3.2 and 0.8 years, respectively. In a patient with stage IB disease, a mediastinal metastasis and a malignant pleural effusion developed 5.6 years after diagnosis, and the patient died of disease at 6.2 years. Another patient with stage IB disease and a positive vaginal cuff margin that recurred locally after 1.7 years received chemotherapy and was alive and clinically free of disease at 2.5 years. Mesonephric adenocarcinomas were immunoreactive for epithelial markers (AE1/3; CK1, CAM 5.2, cytokeratin 7, and epithelial membrane antigen) (100%), calretinin (88%), vimentin (70%), androgen receptor (33%), and inhibin (30%, focal staining). No immunostaining was detected with cytokeratin 20, estrogen receptor, progesterone receptor, and monoclonal carcinoembryonic antigen. This staining profile is similar to that of mesonephric remnants and may be useful in the distinction of mesonephric carcinoma from mullerian endometrioid adenocarcinoma, with which it may be confused.

Adult↗
PubMed2001

Allelic losses at 3p and 11p are detected in both epithelial and stromal components of cervical small-cell neuroendocrine carcinoma.

Microdissected epithelial and stromal cells from 15 cervical small-cell carcinoma patients and 9 healthy control subjects were assessed for loss of heterozygosity with polymorphic DNA markers at chromosomes 3p and 11p. Among malignant lesions assessed with 7 markers at 3p, 21 allelic losses were detected from 193 informative samples. Of losses, 20 were in epithelial and 1 was in normal-appearing stromal cells. Among losses in epithelial cells, 16 were from 44 samples informative for 3 markers within 3p21.2-p14.2 (0.36 loss/sample), whereas only 4 were from 54 samples informative for 4 markers outside the region (0.09 loss/sample), suggesting a "hot spot" of genetic alterations within 3p21.2-p14.2. Among malignant lesions assessed with 2 markers within 11p14-p12, 15 losses were seen in 52 informative samples. Of losses, 10 were in epithelial and 5 were in normal-appearing stromal cells. Of 10 epithelial samples showing losses within 11p14-p12, 8 also displayed losses within 3p21.2-p14.2, suggesting a concurrent involvement of these loci in tumor development or progression. The five losses in stromal cells were in four cases that showed no loss in epithelial cells with same markers, suggesting that stromal cells might play initiative roles in tumor development.

Alleles↗
PubMed2000

Concurrent and independent genetic alterations in the stromal and epithelial cells of mammary carcinoma: implications for tumorigenesis.

The high frequency of loss of heterozygosity (LOH) in epithelial cells of mammary ductal carcinoma in situ (DCIS) and IDC is a well known phenomenon, whereas the genetic abnormalities in the mammary stroma and its influence on the epithelial component have not been sufficiently studied. Using the PCR, we examined DNA extracts from microdissected stromal and epithelial tissues of 11 breast samples containing DCIS, including five cases associated with IDC. In each case, the mesenchymal tissue consisting of normal-appearing stroma at a distance from DCIS and IDC or stroma close to either DCIS or IDC was manually microdissected. Epithelial cells from morphologically clear-cut normal ducts and lobules, DCIS, and IDC were also microdissected. Twelve polymorphic DNA markers were tested to identify possible genetic alterations in the mesenchymal and epithelial cells on chromosomes 2p, 3p, 11q, 16q, and 17q. Samples from bilateral reduction mammoplasty from 10 women without any clinical, radiological, or pathological abnormalities were also selected as a control (reduction mammoplasty group). Whereas most cases (8/11, 73%) displayed at least one identical LOH in both epithelial and mesenchymal components, LOH at several loci was noted exclusively in stromal cells. The most frequent genetic alterations in the mesenchymal cells were at chromosomes 17q24, 16q23.1-24.2, 3p14.2, and 11q21-23.2, in 87.5, 62, 60, and 45% of informative cases, respectively. The LOH frequency in the stroma close to cancer ranged from 10 to 66.5% for DCIS and from 20 to 75% of informative cases for IDC. Furthermore, 10 of the 12 polymorphic markers revealed LOH in the stroma at a distance, ranging from 11 to 57% of informative cases. None of the control cases (women without any breast disease) revealed LOH either in the epithelial or in the stromal components. Our findings strongly support the concept of stromal-epithelial interaction in the development and progression of mammary neoplasia. Furthermore, this study suggests that genetic alterations in the stromal cells may precede genotypic changes in the epithelial cells. At least in some cases, the mammary stroma in DCIS or IDC apparently represents a neoplastic interactive component rather than a reactive response to the carcinoma. The frequent allelic loss (LOH) in the mammary stroma, identified in our study, may explain some of the fibroblastic abnormalities previously observed in patients with breast carcinoma or a variety of cancer-associated hereditary diseases. We conclude that the mammary stroma may play a key role in inducing neoplastic transformation of epithelial cells, recapitulating its role in normal mammary duct development.

Breast Neoplasms↗
PubMed2000

Genetic abnormalities in mammary ductal intraepithelial neoplasia-flat type ("clinging ductal carcinoma in situ"): a simulator of normal mammary epithelium.

BACKGROUND: Mammary ductal intraepithelial neoplasia (DIN)-flat type ("clinging ductal carcinoma in situ [DCIS]") generally is a subtle epithelial alteration characterized by one or a few layer(s) of atypical cells replacing the native epithelium. The "low power" appearance of DIN-flat type can be misinterpreted easily as "normal" because of the frequent absence of multilayered proliferation and often subtle cytologic atypia. Because it presents as an often unrecognized lesion or in association with tubular carcinoma, to the authors' knowledge the clinical and biologic significance of this lesion has not been well established. METHODS: Using polymerase chain reaction, the authors examined DNA extracts from microdissected areas of 22 cases with extensive "clinging DCIS," including 13 cases associated with infiltrating ductal carcinoma as well as 5 cases associated with more conventional types of DCIS. Eight polymorphic DNA markers with a high rate of loss of heterozygosity (LOH) in classic types of DCIS were selected to identify possible genetic alterations on chromosomes 2p, 3p, 11q, 16q, and 17q. Two cases also were used for the assessment of clonality by means of X chromosome inactivation (methylation pattern of the human androgen receptor [HUMARA] gene). RESULTS: LOH was detected in 17 of 22 lesions (77%), and monoclonality was established in the 2 cases analyzed. The most common genetic alterations were at chromosomes 11q21-23.2, 16q23.1-24.2, and 3p14.2 with LOH in 50%, 45%, and 41%, respectively, of informative cases. The DIN-flat type showed the same genetic alterations (LOH) identified in adjacent in situ and infiltrating ductal carcinoma. In contrast to the DIN-flat type, the perfectly normal mammary epithelium was associated very infrequently (1 of 16 cases; 6%) with LOH. CONCLUSIONS: The DIN-flat type represents one of the earliest, morphologically recognizable, neoplastic alterations of the breast. Recognition of the DIN-flat type is important not only for the early detection of intraductal neoplasia but also to prevent misinterpretation and utilization of this lesion as a normal control in studies. This distinctive lesion could be crucial as an explanation for at least part of the > 20% reported incidence rate of breast carcinoma recurrence observed despite ostensibly "negative" margins of breast biopsies.

Adenocarcinoma↗
PubMed2000

The mammary pathology of genetically engineered mice: the consensus report and recommendations from the Annapolis meeting.

NIH sponsored a meeting of medical and veterinary pathologists with mammary gland expertise in Annapolis in March 1999. Rapid development of mouse mammary models has accentuated the need for definitions of the mammary lesions in genetically engineered mice (GEM) and to assess their usefulness as models of human breast disease. The panel of nine pathologists independently reviewed material representing over 90% of the published systems. The GEM tumors were found to have: (1) phenotypes similar to those of non-GEM; (2) signature phenotypes specific to the transgene; and (3) some morphological similarities to the human disease. The current mouse mammary and human breast tumor classifications describe the majority of GEM lesions but unique morphologic lesions are found in many GEM. Since little information is available on the natural history of GEM lesions, a simple morphologic nomenclature is proposed that allows direct comparisons between models. Future progress requires rigorous application of guidelines covering pathologic examination of the mammary gland and the whole animal. Since the phenotype of the lesions is an essential component of their molecular pathology, funding agencies should adopt policies ensuring careful morphological evaluation of any funded research involving animal models. A pathologist should be part of each research team.

Animals↗
PubMed2000

Ossifying well-differentiated Sertoli-Leydig cell tumor of the ovary.

A unique case of an ovarian sex cord-stromal tumor occurring in a pregnant 20-year-old is described. The tumor showed central ossification on macroscopic examination. Microscopically, cords and nests of Sertoli cells were identified, mostly away from the abundant central hyalinization, calcification, and ossification. A small number of Leydig cells were present, with isolated Reinke crystals. The presence of these cells could reflect luteinized stromal cells secondary to pregnancy. The Sertoli cells were dominant and the calcified/ossified areas were at the center of a dominant Sertoli nodule. This degree of ossification has never been reported in either ovarian Sertoli tumors or well-differentiated Sertoli-Leydig tumors. Calcifying Sertoli cells neoplasms have been described in the testis, but this case appears to be the first description of a case with similar features in the ovary.

Adult↗
PubMed2000

Teratomatous genotype detected in malignancies of a non-germ cell phenotype.

Originating from post-meiotic germ cells, mature ovarian teratomas (MOT) are genetically homozygous tumors within heterozygous hosts. MOT may be associated with malignant tumors of a non-germ cell phenotype (so-called malignant transformation). Based on the presence of in situ changes, some cases have been hypothesized to arise from teratomatous tissue. However, other malignancies associated with mature teratomas, such as sarcomas, may originate from either teratomatous elements or preexisting somatic ovarian tissue. Eight cases of MOT containing various histologic types of malignancy, including four squamous cell carcinomas, two sarcomas, one thyroid carcinoma, and one carcinoid tumor, were selected for study. Using selective tissue microdissection and PCR-based analysis of the extracted DNA, we compared the genotypic pattern of the mature teratomatous components to the associated malignant neoplasm with a random panel of highly informative genetic markers for different chromosomes. In all eight cases, genetic analysis of the malignant component revealed a homozygous genotype. In seven cases, the genetic profiles of mature teratomas and the associated malignant tumors were identical, suggesting a direct pathogenetic relationship between these lesions. In one case, the malignant component revealed homozygosity of different alleles compared with mature teratoma, suggesting independent teratomatous growth processes. This finding indicates that some ovarian malignancies of the non-germ cell phenotype arise in teratoma and fall into the spectrum of germ cell tumors.

DNA, Neoplasm↗