Genome Wide DNA Methylation Profiles Provide Clues to the Origin and Pathogenesis of Germ Cell Tumors

The cell of origin of the five subtypes (I-V) of germ cell tumors (GCTs) are assumed to be germ cells from different maturation stages. This is (potentially) reflected in their methylation status as fetal maturing primordial germ cells are globally demethylated during migration from the yolk sac to the gonad. Imprinted regions are erased in the gonad and later become uniparentally imprinted according to fetal sex. Here, 91 GCTs (type I-IV) and four cell lines were profiled (Illumina’s HumanMethylation450BeadChip). Data was pre-processed controlling for cross hybridization, SNPs, detection rate, probe-type bias and batch effects. The annotation was extended, covering snRNAs/microRNAs, repeat elements and imprinted regions. A Hidden Markov Model-based genome segmentation was devised to identify differentially methylated genomic regions. Methylation profiles allowed for separation of clusters of non-seminomas (type II), seminomas/dysgerminomas (type II), spermatocytic seminomas (type III) and teratomas/dermoid cysts (type I/IV). The seminomas, dysgerminomas and spermatocytic seminomas were globally hypomethylated, in line with previous reports and their demethylated precursor. Differential methylation and imprinting status between subtypes reflected their presumed cell of origin. Ovarian type I teratomas and dermoid cysts showed (partial) sex specific uniparental maternal imprinting. The spermatocytic seminomas showed uniparental paternal imprinting while testicular teratomas exhibited partial imprinting erasure. Somatic imprinting in type II GCTs might indicate a cell of origin after global demethylation but before imprinting erasure. This is earlier than previously described, but agrees with the totipotent/embryonic stem cell like potential of type II GCTs and their rare extra-gonadal localization. The results support the common origin of the type I teratomas and show strong similarity between ovarian type I teratomas and dermoid cysts. In conclusion, we identified specific and global methylation differences between GCT subtypes, providing insight into their developmental timing and underlying developmental biology. Data and extended annotation are deposited at GEO (GSE58538 and GPL18809).     

Craniofacial Dermoid Cysts: Histological Analysis and Inter-site Comparison

Introduction: Dermoid cysts are common, benign, embryologically derived soft tissue cysts that can arise at a variety of craniofacial sites. It is not known whether specific histological variations exist between the different craniofacial sites. This study aims to establish whether inter-site histologic differences exist between periorbital, nasal, scalp, and postauricular dermoid cysts and analyze these in context of their distinct embryological origin and varied clinical presentation.Methods: A retrospective review of craniofacial dermoid cysts was performed. Using light microscopy with hematoxylin and eosin staining, histological appearance was directly compared between craniofacial sites.Results: All (n = 16) cysts contained keratinizing, stratified squamous epithelial lining, intraluminal keratin, and hair. Sebaceous glands were commonly present (n = 13). Eccrine (sweat) glands were less common (n = 3). Structures of mesodermal origin were seen in three periorbital cysts. Only the six ruptured cysts showed evidence of inflammation.Conclusions: Histological properties of dermoid cysts are conserved between craniofacial sites (periorbital, nasal, scalp, and postauricular). This reflects the consistency of ectodermal inclusion during early embryological development, which is independent of specific craniofacial site or surrounding anatomical structures.     

"Keystone" approach for intracranial nasofrontal dermoid sinuses

Nasofrontal dermoid sinus tracts that extend intracranially through the foramen cecum or ethmoid can be difficult to completely resect. Complete extirpation of nasofrontal dermoid sinus cysts is essential for effective treatment of this problem to minimize the chance of recurrence. The authors describe a new technique based on parasagittal osteotomies through the supraorbital bar, or bandeau, that ensures that the resection of the nasofrontal dermoid sinus cysts is complete. This technique also limits the size of the external nasal incision and enhances the surgeon's exposure of the anterior cranial base for resection of intradural extension. This approach also enhances exposure for the direct repair of the dura and the cranial vault.     

Angular dermoid cysts in the endoscopic era: retrospective analysis of aesthetic results using the direct, classic method

The concept of the endoscopic approach was recently introduced for the removal of angular dermoid cysts. Therefore, it was considered necessary to evaluate the conventional direct incisional approach for angular dermoid cyst excision, with respect to long-term aesthetic results and complications. The need to change from the direct excisional technique to the endoscopic approach in hair-bearing areas was investigated. During a 25-year period, 95 children were surgically treated by a single surgeon (H.G.T.) for removal of angular dermoid cysts. Only 22 patients (23 percent) were available for reassessment. The follow-up periods after the excisional procedure were 1 to 12 years. Assessments were performed by a 15-member team of assessors, who scored the aesthetic results of the scars with comparative slides. In addition, a questionnaire was mailed to each family, to document the family members' perceptions of the aesthetic appearance of the scar. Twenty-eight families (29 percent) responded. The complications were determined through the medical records department. For 19 of 22 patients (86 percent), the scar was scored by 85 percent of the assessors as excellent or good. No assessor stated that a scar was unacceptable. In the family questionnaires, 26 of 28 families (93 percent) reported an excellent scar and two (7 percent) reported a fair scar. No family stated that the scar was unacceptable. The operative notes for the 95 patients revealed that only two cysts had ruptured during the surgical procedure (2 percent) and only one infection had occurred (1 percent). No other major complications were reported. It is concluded that the direct method for dermoid cyst excision is an excellent approach, with a low complication rate and a very high aesthetic success rate, when performed through a supra-eyebrow or infra-eyebrow incision.     

Tailgut cyst associated with a carcinoid tumor: case report and review of the literature

We report the case of a 49-year-old woman who presented a tailgut cyst lined by a variety of epithelium including squamous, columnar and transitional. Fortuitously a microscopic carcinoid tumor expressing immunohistochemically neuroendocrine markers was identified in the cystic wall. Tailgut cysts are congenital abnormalities located in the presacrococcygeal area occurring usually in adult patients. Clinical diagnosis is difficult because they are often asymptomatic. Patients may present symptoms resulting from local mass effects or complications. The differential diagnoses include rectal duplication cysts, cystic sacrococcygeal teratomas, epidermal cysts, epidermoid cysts, anal duct or gland cysts. Magnetic resonance imaging has recently become the modality of choice to image the cyst. Malignant transformation is rare; 23 cases including 10 carcinoid tumors have been reported in the literature. To our knowledge, this is the eleventh case of carcinoid tumor arising in a tailgut cyst.     

Mouse Genital Ridges in Organ Culture: The Effects of Temperature on Maturation and Experimental Induction of Teratocarcinogenesis

Abstract. Testicular teratomas can be induced experimentally by grafting genital ridges from male mouse fetuses to the testes of adults. A high incidence of teratomas occurs in genital ridges grafted to scrotal testes, but not in genital ridges grafted to testes maintained at body temperature. Genital ridges were cultured at 32° C or 37° C prior to grafting to the testes to determine the effect of temperature on the incidence of teratomas. Genital ridges cultured at 32° C for two or three days produced a high incidence of teratomas when grafted to the testes, in contrast to genital ridges cultured at 37° C for two or three days which produced a low incidence. Histologically, genital ridges cultured at 32° C contained disorganized testicular tubules and were retarded in development. Genital ridges continued to develop in vitro at 37° C, but were histologically different from genital ridges maturing in the fetus. Genital ridges cultured at 32° C for 10 to 12 days did not develop teratomas in vitro or after grafting to the testes. Further characterization of temperature effects in vitro may lead to a better understanding of teratocarcinogenesis in vivo.     

Unusual abdominal cysts in infants and children

In a 20-year period at the Los Angeles Children's Hospital, 46 infants and children have had operation for cysts within the abdomen. The age range of patients was from newborn to 13 years. Most of them were under four years old. There were four general groups of these cysts. (1) About one-half were cysts of the ovary, some of them serous and some dermoid. These cysts are attached by a stalk that often twists, causing gangrene or rupture with acute symptoms simulating appendicitis. (2) Next in frequency were cysts arising in the mesentery of the intestine. They usually caused little trouble until by their size (up to a 2-quart capacity) they created pressure and obstruction in the intestine. (3) Enteric cysts were found in four patients. (4) Cysts of the pancreas were present in three of the children.X-ray examination was helpful in diagnosis. Usually the type of cyst was not determined until operation was done. Transection of the intestinal tract sometimes was necessary for removal of the cyst. Surgical correction was satisfactory in 44 of the 46 cases.     

Aspiration cytology of 147 adnexal cysts with histologic correlation.

OBJECTIVE: To assess the usefulness of cytology in the diagnosis of 147 histologically established adnexal cysts. STUDY DESIGN: Retrospective, macro-microscopic study based on fluid aspirated from 132 ovarian and 15 extraovarian cysts and projected as a cytohistologic correlation. RESULTS: Typical macroscopic features were identified in 76% of endometriotic cysts, in 53% of mucinous neoplasms and in 67% of dermoid cysts. Cytology helped to identify 67% of nonneoplastic and 56% of neoplastic cysts. The lowest diagnostic sensitivities were observed in functional cysts and benign serous neoplasms (50%), while the highest were shown by endometriotic cysts (76%) and malignant epithelial neoplasms (71%). Inadequate samples were obtained from all types of cysts, even malignant ones (two mucinous cystadenocarcinomas). Diagnostic cytology was useless in extraovarian cysts (33% sensitivity). An adult granulosa cell tumor was erroneously diagnosed as a follicular cyst by cytologic examination. CONCLUSION: Examination of the cyst fluids obtained by aspiration demonstrated low sensitivity, with 43% of inadequate samples obtained from all types of cysts. Malignant cystic neoplasms may be overlooked in inadequate samples. Our study also revealed that specificity in this type of analysis is high in inadequate samples, provided that the technique is carried out correctly.     

Fine needle aspiration cytology in ovarian lesions: an institutional experience of 584 cases

N. Gupta, A. Rajwanshi, L. K. Dhaliwal, N. Khandelwal, P. Dey, R. Srinivasan and R. Nijhawan
Fine needle aspiration cytology in ovarian lesions: an institutional experience of 584 cases Objective: To assess the diagnostic value of fine needle aspiration cytology (FNAC) in ovarian lesions. Methods: This was a retrospective study of ultrasound‐guided (US) FNAC of 584 ovarian lesions from January 1998 to July 2010. The lesions were categorized into non‐neoplastic lesions, neoplastic lesions and inadequate aspirates. The results were compared with the corresponding histopathology whenever available. Results: Of the 584 lesions, 180 (30.8%) were reported as non‐neoplastic (48 non‐specific inflammation, 11 tuberculosis, 63 functional cysts and 58 endometriotic cysts), 249 (42.6%) as neoplastic (81 benign lesions/tumours and 168 malignant) and 155 (26.5%) as inadequate. Based on the subsequent histopathology, which was available in 121 (20.7%), the cases were divided into those that were concordant and discordant. Concordant cases comprised 92/121 (76%), including 28 non‐neoplastic lesions (seven non‐specific inflammation, nine functional cysts and 12 endometriotic cysts), 42 surface epithelial tumours (13 benign and 29 malignant), 10 germ cell tumours (five mature cystic teratomas and five mixed germ cell tumours), seven sex‐cord stromal tumours (three granulosa cell tumours, one sclerosing stromal tumour, one strümal leutoma, one Sertoli Leydig cell tumour and one malignant Sertoli cell tumour) and five miscellaneous lesions (one plasma cell tumour, two leiomyosarcomas and two cases of necrosis). Discordant cases comprised 29/121 (24%) (21were inconclusive or inadequate on cytology), including four endometriotic cysts, 14 surface epithelial tumours (one cystadenofibroma, one borderline mucinous tumour and 12 carcinomas), five germ cell tumours (two immature teratomas and three mature cystic teratomas), two thecomas, one fibroma, one sclerosing stromal tumour, one fibrosarcoma and one myxoma. FNAC sensitivity for a diagnosis of malignancy was 85.7%, specificity 98.0%, positive predictive value 97.7%, negative predictive value 87.7% and accuracy 92.0%, if 21 inconclusive/inadequate FNACs were excluded; with the latter taken as false negatives, sensitivity was 73.7% and accuracy 76.0%. Conclusion: FNAC has a high specificity for diagnosis of ovarian/adnexal lesions but greater experience is required for the accurate subtyping of neoplasms and sensitivity is limited by inconclusive/inadequate results.     

Craniofacial dermoids

Thirty-two patients with nasal dermal sinuses and cysts were treated during the 10-year period from 1978 to 1987. These patients presented with midline cysts (N = 18) or sinus ostia (N = 14). Only 6 of the 32 patients manifested intracranial extension (19 percent). All the patients with intracranial extension exhibited an intracranial mass on preoperative CT scans. Ten patients with no CT evidence of intracranial mass were noted to have only a fibrous cord extending to the base of the foramen cecum. In 4 of these 10 patients, craniotomy confirmed that there was no intracranial extension of the dermoid. Four other patients presented with sinus ostia at the base of the columella. None of these 4 patients had intracranial extension. Clinical examination and preoperative CT scans provide most of the information needed to determine the nature, course, and extent of these lesions.     

Ovarian cysts and their consequences on the reproductive performance of swine herds

The aim of this work was to determine the incidence of ovarian cysts in the breeding herd and their consequences in the reproductive performance of the herd. Data from 1990 cyclic sows from two farms, with 0-12 parities, lactation length between 6 and 47 days and weaning-estrus interval between 0 and 32 days were evaluated by ultrasound examination for cyst incidence. As cyst was considered an anaechoic structure with smooth and thin walls with a diameter larger than 2 cm that remained visible for at least 5 days after estrus onset. Cyst incidence was found to be 2.4%. Sows with ovarian cysts have a greater return to estrus rate (34.0 x 7.7%, P<0.01), and cysts were associated with around 10% of regular and irregular return to estrus patterns on both farms. The adjusted farrowing rate (52.2 x 90.0%, P<0.01) and anestrual sows that were not pregnant (10.6 x 0.6%, P<0.01) were also influenced by the appearance of ovarian cysts, but they did not influence litter size (P>0.05). The incidence of cysts was not influenced by parity (P>0.05). Sows with shorter lactation had a greater incidence of cysts (P<0.05). Sows with a weaning-estrus interval shorter than 3 days had a greater incidence of ovarian cysts (P<0.05). The time of the year had no influence on the incidence of ovarian cysts (P<0.05).     

Ocular dermoids

The following types of ocular dermoids were seen in a retrospective study of 50 children with these lesions: 34 epibulbar dermoids, 12 lipodermoids, and 4 dermoid cysts. Forty-six percent had hemifacial microsomia, and one-half of these had additional stigmata of the Goldenhar variant of the syndrome. Ninety-seven percent of the dermoids were found in the temporal half of the globe; of these, 76 percent were in the inferolateral quadrant, straddling the corneoscleral limbus. The majority of children had an oblique astigmatism in the involved eye. Epibulbar dermoids may be removed by careful superficial keratectomy, but caution should be exerted in excising lipodermoids because of the risks of affecting ocular motility and tear secretion.     

Midline (dermoid) cysts of the floor of the mouth: report of 16 cases and review of surgical techniques

A retrospective review of 16 cases of midline (dermoid) cysts of the floor of the mouth is presented, evaluating the different surgical approaches. Sixteen cases of patients with a diagnosis of midline cyst of the floor of the mouth, treated at the Maxillofacial Surgery Department of the School of Medicine and Surgery of the "Federico II" University of Naples (Naples, Italy), were observed over a 10-year period, between 1988 and 1998; age, sex, localization, diagnostic technique, and type of treatment were evaluated. Male patients were more frequently affected, with a male-to-female ratio of 3:1 (12:4 cases). Patients ranged in age from 5 to 51 years (average age, 27.8 years). The preoperative assessment was made using ultrasonography in all cases but one, computed tomography in eight cases, and magnetic resonance imaging in three cases. Regarding surgical techniques used, a transcutaneous approach was adopted for median geniohyoid cysts, an extended median glossotomy technique was used for very large median genioglossal cysts, a median glossotomy technique was used for median genioglossal cysts, and a midline incision of the oral mucosa along the lingual frenulum was used for sublingual cysts. During the postoperative course, there were no complications except for modest edema in three cases. Follow-up ranged between 24 months and 12 years; no relapses or malignant changes were observed. In the authors' experience, the intraoral approach was also effective for the treatment of large lesions and led to very good cosmetic and functional results, whereas the extraoral incision was necessary only when the cysts were under the geniohyoid muscle.     

The ter mutation responsible for germ cell deficiency but not testicular nor ovarian teratocarcinogenesis in ter / ter congenic mice

The ter (teratoma) gene causes germ cell deficiency and a high incidence of congenital testicular teratomas derived from primordial germ cells in 129/Sv- ter strain mice. Ovarian teratomas in LTXBJ mice originate from ovarian parthenotes. In order to study the function of the ter gene in germ cell development and teratocarcinogenesis, we examined the influence of a foreign genetic background on the ter action by introducing the ter gene of 129/Sv- ter strain mice into C57BL/6J, LTXBJ and C3H/HeJ genetic backgrounds by the backcross method and by thus establishing B6- ter , LTXBJ- ter and C3H- ter ter congenic strains, respectively. Histological analysis showed that germ cell deficiency occurred in both sexes of the ter mutants, through the fetal stages to adulthood, but that congenital testicular teratocarcinogenesis did not occur after the fifth backcross generation. The ter/ter gonads were smaller than normal (+/+ or +/ ter ). Experimental testicular teratomas never developed from intratesticular grafts of B6- ter genital ridges. LTXBJ- ter/ter females had no ovarian teratomas. It is concluded that the ter gene is solely responsible for germ cell deficiency, but not testicular teratocarcinogenesis, in ter congenic strains having background genes other than 129/Sv- ter and that the ter gene is not involved in ovarian teratocarcinogenesis.     

Steroid biochemistry and categorization of breast cyst fluid: relation to breast cancer risk

Patients bearing macrocysts of the breast are at higher risk of later developing cancer. The fluid filling the cysts (breast cysts fluid, BCF) contains unusual amounts of steroid conjugates, first androgen and estrogen sulfates. Measuring BCF cations (K⁺, Na⁺) allows categorization of cysts into two major subsets (type I and type II) that are associated with a different degree and/or turnover of apocrine metaplastic cells in the lining epithelium. Type I cysts (high K⁺/ Na⁺ ratio) accumulate huge amounts of dehydroepiandrosterone sulfate, estrone sulfate, androstane-3, 17β-diol glucuronide, androsterone glucuronide and contain more testosterone and dihydrotestosterone than type II. Conversely, type II cysts (low K⁺/Na⁺ ratio) contain more progesterone and pregnenolone. A cohort study was started in 1983 at the Cancer Prevention Center, Ravenna, Italy, with the aim of evaluating the relationships between the biochemistry of BCF and the incidence of breast cancer in women with gross cystic disease (GCD) of the breast. The bimodal distribution of the cationic pattern has been confirmed from data obtained in 798 patients aspirated. The risk of cyst relapse was significantly higher among women with type I cysts or with multiple cysts at presentation. Twelve incident cases of breast cancer have been diagnosed among women whose BCF was categorized. Eleven out of 12 cases had type I or multiple cysts. The cumulative incidence of breast cancer among patients bearing type I cysts was 2.5%. We conclude that women with GCD bearing type I cysts have an increased breast cancer risk when compared with the counterpart bearing type II cysts or the general population.     

Teratogenic effects of parthenogenetic cells from LTXBO mice,a strain which develops ovarian teratomas at high frequency

Summary LTXBO mice develop ovarian teratomas at high frequency. The phenotype of tumour tissues is unusual in that most contain trophoblast elements. Since the tumours are derived from parthenogenetically activated oocytes, they would not be expected to produce trophoblast. The developmental potential of parthenogenetic cells from these mice was tested in aggregation chimeras. No contribution to trophoblast tissues was observed. However, a high incidence of morphological abnormalities was seen, suggesting that the parthenogenetic cells exerted a teratogenic effect.     

Genetics and biology of human ovarian teratomas. I. Cytogenetic analysis and mechanism of origin.

One hundred and two benign, mature ovarian teratomas and two immature, malignant teratomas were karyotyped and scored for centromeric heteromorphisms as part of an ongoing project to determine the chromosomal karyotype and the genetic origin of ovarian teratomas and to assess their utility for gene-centromere mapping. Karyotypic analysis of the benign cases revealed 95 46,XX teratomas and 7 chromosomally abnormal teratomas (47,XXX, 47,XX,+8 [two cases], 47,XX,+15, 48,XX,+7,+12 91,XXXX,-13 [mosaic], 47,XX,-15,+21,+mar). Our study reports on the first cases of tetraploidy and structural rearrangement in benign ovarian teratomas. The two immature cases had modal chromosome numbers of 78 and 49. Centromeric heteromorphisms that were heterozygous in the host were homozygous in 65.2% (n = 58) of the benign teratomas and heterozygous in the remaining 34.8% (n = 31). Chromosome 13 heteromorphisms were the most informative, with 72.7% heterozygosity in hosts. The cytogenetic data indicate that 65% of teratomas are derived from a single germ cell after meiosis I and failure of meiosis II (type II) or endoreduplication of a mature ovum (type III); 35% arise by failure of meiosis I (type I) or mitotic division of premeiotic germ cells (type IV).     

Teratoid Tumors Derived from Mouse Embryos Grown in an Immunologically Privileged Site

Mouse early embryos and embryo fragments were transplanted into an immunologically privileged site, consisting of a glass cylinder previously implanted under the skin of adult mice in order to test their tumor producing potential, in allogeneic adult recipients. The highest yield of tumors was obtained upon transplantation of 6 1/2 day old embryos in toto. i.e., including the embryonic and extraembryonic areas. Histological examination showed teratomas composed of differentiated tissues derived from the three germ layers containing isolated foci of undifferentiated cells and nodules of trophoblast giant cells. Areas exhibiting the histological appearance of yolk sac carcinoma were also observed. Transplantation of the whole 6 1/2 day old egg cylinder, including the ectoplacental cone, and the isolated embryonic area produced a lower incidence of teratomas with a reduced variety of differentiated tissues. No yolk sac carcinoma was found in these grafts. The ectoplacental cone of 6 1/2 day embryos produced no tumors. Grafts of genital ridges from 12 1/2 day embryos gave rise to teratomas with well differentiated tissues of embryonic and extraembryonic origin. Areas ressembling yolk sac carcinoma were also observed. The life span of trophoblastic giant cells within the glass cylinder was significantly longer than in other experimental systems.     

β1 Integrin Is Essential for Teratoma Growth and Angiogenesis

Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of β1 integrin during teratoma formation, we compared teratomas induced by normal and β1-null ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, β1-null ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of β1-null teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in β1-null teratomas. Basement membranes were present but with irregular shape and detached from the cell surface.

Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell–derived endothelial cells. In contrast, β1-null teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although β1- deficient endothelial cells were absent in teratomas, β1-null ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in β1-null embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in β1-null embryoid bodies.