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

Malignant transformation of mature cystic teratoma of the ovary

Mature cystic teratoma is the most common ovarian germ cell neoplasm. Malignant transformation is a rare occurrence, accounting for 1.5%-2% of cases. Malignant changes can arise from any constituent tissue of a teratoma; however, squamous cell carcinoma is the most common histologic type seen, followed by adenocarcinoma and sarcoma respectively. Tumor marker concentration levels, age, and the tumor maximum diameter are predictive indicators for malignant transformation. Proper diagnosis includes recognizing the possibility of malignant transformation versus excluding other differential options, such as metastasis. Primary cytoreductive surgery, adjuvant chemotherapy, and radiotherapy are the current treatment methods. The aim of the review is to discuss the clinical and pathologic features of malignant transformation within mature cystic teratomas, while reviewing the reported malignant types, differential diagnoses, and treatment options. Data sources include review of pertinent peer-reviewed literature on malignant transformation of mature cystic teratoma and cases seen in authors' institutional practice. Mature cystic teratomas are a commonly encountered benign ovarian tumor. However, the possibility of malignant transformation should remain in consideration, especially with given clinical or pathologic features: increased patient age, tumor size, or tumor marker levels. Thorough sampling of solid tumor foci can help identify malignant components. Awareness and proper diagnosis, along with early detection and clinical management, shows improved patient outcomes.

Squamous cell carcinoma arising from mature cystic teratoma of the ovary: A challenging question for gynecologic oncologists

Mature cystic teratomas of the ovary have an incidence of 1.2-14.2 cases per 100.000 people per year. Malignant transformation occurs in approximately 2% of the cases, and usually consists of squamous cell carcinoma. The preoperative detection is difficult and the diagnostic accuracy of ultrasound, magnetic resonance imaging, and computed tomography is debated. The diagnosis is frequently made in the operating room or on final histological examination. Standard treatment consists of bilateral salpingo-oophorectomy, total hysterectomy and comprehensive surgical staging in early disease and optimal cytoreductive surgery in advanced disease. Paclitaxel/carboplatin- based chemotherapy is the most used adjuvant treatment, whereas more aggressive regimens can be adopted in patients with high tumor burden or recurrent disease. The efficacy of radiotherapy is still unproven. The prognosis is poor when the tumor has spread beyond the ovary. There are few information to provide commonly accepted guidelines for this malignancy.

Bilateral ovarian angiosarcoma arising from the mature cystic teratomas - A case report and review of the literature

INTRODUCTION

Ovarian teratomas undergo the malignant transformation in 0.2-2% of cases. The behavior of malignancies in mature cystic teratomas (MCT) is determined by their phenotype and not their derivation from germ cells. We can recognize pure angiosarcomas or as a part of other tumors like malignant mixed Mullerian tumors and adenosarcomas.

PRESENTATION OF CASE

We present the first case of bilateral ovarian angiosarcoma arising from the mature teratomas. Due to widespread disease, we performed limited surgical procedure consisting of bilateral adnexectomy and omentectomy. Exploratory laparotomy in 44-year old patient showed massive ascites, necrotic tissue of omentum and bilateral tumors originating from both ovaries measuring 8 and 6cm with necrotic surface. Immunohistochemistry of the tumors showed positive staining for CD31, vimentin, desmin and focal positivity for CD34.

DISCUSSION

Sarcomas of gynecologic origin are extremely rare tumors. They present with unspecified symptoms and are diagnosed in late stages of the disease. The appropriate management of angiosarcomas is difficult due to the rarity of disease and late stage of the diseases. Surgical therapy should contain the hysterectomy with bilateral salpingo-oophorectomy and omentectomy. Pelvic lymphadenectomy was not performed in published cases with no effect on patient survival.

CONCLUSION

This work summarizes the current knowledge in the diagnosis and treatment of angiosarcomas arising in the mature teratomas. Promising results are expected from the trials devoted to antiangiogenic strategies in treatment of aggressive sarcomas.

Leiomyosarcoma and Squamous Cell Carcinoma Arising in Mature Cystic Teratoma of the Ovary

The occurrence of malignant transformation in mature cystic teratoma of the ovary is rare, with squamous cell carcinoma being the most common histologic type. Sarcomatous transformation has been rarely described in the literature. We present a case of leiomyosarcoma with a minor component of squamous cell carcinoma arising in mature cystic teratoma of ovary in a 65-year-old woman. The malignant tumor showed two distinct components of sarcomatous and invasive epithelial elements, which were confirmed by immunostaining. To our knowledge, only four cases of leiomyosarcoma in ovarian mature cystic teratoma have been reported and this is a unique case report of leiomyosarcoma and squamous cell carcinoma arising in a mature cystic teratoma of ovary.

Immature ovarian teratoma with unusual gliomatosis

This study aimed to investigate an unusual case of immature ovarian teratoma with onset of mature glial cells implanted on the contralateral ovary, a challenge in the diagnosis of the second ovarian tumor. We report the case of a 31- yr-old woman, who developed at the age of 16 an immature teratoma in the right ovary that was surgically removed. Six years later mature glial implants were present on the left ovary and six months later at the level of peritoneum that relapsed after other six months. The patient suffered three surgical resections after the initial one. Paraffin sections and immunohistochemical examinations using antibodies against glial and neuronal antigens were performed. In the teratoma, the neuroectodermal tissue expressed Glial fibrillary acidic protein (GFAP), S100 protein, Epithelial membrane antigen (EMA) and Cytokeratin 34 beta E12 (Ck34beta E12), wheares the implants expressed only GFAP and S100 protein. The immature teratoma is the rarest type of ovarian teratomas. Gliomatosis peritonei is an exceptional finding, expecially with onset on the contralaterally ovary. The implant of the mature glial cells has a high risk of relapse, as seen in our case, thus close follow-up of the patient is necessary.

Molecular genetic evidence supporting the neoplastic nature of fibrous stroma in testicular teratoma

Testicular teratoma typically consists of heterogeneous mixtures of diverse epithelial and stromal components. The biological nature and genetic characteristics of the fibrous stroma of testicular teratomas have not been thoroughly investigated. Chromosome 12p abnormalities are the hallmark genetic alterations of germ cell tumors. We studied chromosome 12p abnormalities in the fibrous stroma and other components of pure testicular teratomas from 32 patients using interphase fluorescence in situ hybridization. Overall, 72% (23/32) of pure testicular teratomas had chromosome 12p abnormalities. Isochromosome 12p or 12p overrepresentation independent of isochromosome 12p was detected in the fibrous stroma in 53% (17/32) and 41% (13/32) of cases, respectively. Among the 17 cases positive for isochromosome 12p, 8 (47%) also had 12p overrepresentation. In 31% (10/32) cases, the fibrous stroma showed neither 12p overrepresentation nor isochromosome 12p. Isochromosome 12p and 12p overrepresentation were identified, respectively, in the gastrointestinal-type epithelium of 14/23 (61%) and 15/23 (65%) cases; in the respiratory-type epithelium of 41% (7/17) and 41% (7/17) cases; in the squamous epithelium of 62% (8/13) and 54% (7/13) cases; and in the cartilage of 63% (5/8) and 38% (3/8) cases. Concordant chromosomal 12p abnormalities were observed between the fibrous stroma and epithelial elements of testicular teratomas. Our results indicate that the fibrous stroma of testicular teratomas frequently has genetic abnormalities similar to those of the epithelial components. Concordant chromosome 12p alterations between the fibrous stroma and epithelial elements provide further evidence that both epithelial and fibrous components of teratoma are derived from a common progenitor.

[Mixed germ cell tumor of the ovary with rhabdomyosarcomatous component. A case report]

Malignant germ cell tumors of the ovary are rare representing 3% of all ovarian neoplasms. Hence, they are the most common ovarian malignancy in girls and young women and account for approximately two-thirds of the ovarian cancers that occur in the first two decades of life. Germ cell tumors constitute a heterogeneous group of tumors and are often mixed associating at least two different tumoral components. Exceptionally, sarcomatous areas can be found. We present a case of a 15-year old girl admitted for a voluminous left ovarian mass revealed by pelvic pain. Pathological examination of the dissected material revealed the tumor to be a mixed germ cell tumor (immature teratoma and yolk sac tumor) with rhabdomyosarcomatous component of embryonal type. Clinico-pathological characteristics of such ovarian tumors will be discussed with emphasis on diagnostic difficulties.

Angiosarcoma arising in mature cystic teratoma of the ovary: a case report and review of the literature

Mature cystic teratoma of the ovary is the most common ovarian tumor. Malignant transformation of this neoplasm is rare and is mostly represented by squamous carcinoma. Less frequently, malignant transformation is represented by a sarcoma. To date, only 5 cases of angiosarcoma arising in a mature cystic teratoma of the ovary have been reported. Herein, we report the clinicopathologic features of one such case. A review of the literature is also presented.

Ovarian Mucinous Tumors Associated With Mature Cystic Teratomas

Most primary ovarian mucinous tumors are of surface epithelial-stromal origin and exhibit diffuse expression of cytokeratin 7 (CK7) combined with variable expression of cytokeratin 20 (CK20); this immunoprofile distinguishes them from most lower gastrointestinal tract tumors secondarily involving the ovaries. The uncommon ovarian mucinous tumors of germ cell (teratomatous) origin have not been extensively evaluated to determine the utility of these markers and other markers of intestinal differentiation for distinguishing these tumors from metastatic gastrointestinal tract mucinous tumors. Immunohistochemical expression of CK7, CK20, CDX2, and villin was assessed in 44 ovarian mucinous tumors associated with a mature cystic teratoma. All cases lacked evidence of a nonovarian primary mucinous tumor. All mucinous tumors were unilateral; 6 cases had bilateral teratomas. All tumors displayed gastrointestinal-type mucinous differentiation, with epithelium that was commonly goblet cell-rich or hypermucinous; 21 were associated with pseudomyxoma ovarii and 3 of these had pseudomyxoma peritonei. Tumor architecture ranged from purely cystadenomatous (n=24), to proliferative (n=13), to carcinomatous (n=6); some tumors had admixtures of these patterns. One tumor had a goblet cell carcinoidlike pattern with pseudomyxoma ovarii. Three carcinomas had a signet ring cell component. Cystadenomatous tumors without pseudomyxoma ovarii (n=15) exhibited all possible CK7/CK20 coordinate expression profiles with nearly equal frequency. All proliferative tumors without pseudomyxoma ovarii (n=8) expressed CK7, most often in combination with CK20 expression. All cystadenomatous and proliferative tumors with pseudomyxoma ovarii (n=9 and n=5) were CK7-/CK20+. All carcinomatous tumors had pseudomyxoma ovarii; 3 were CK7-/CK20+, 2 were CK7+/CK20+, and 1 was CK7+/CK20-. The presence of pseudomyxoma ovarii was significantly associated with a CK7-/CK20+ profile (86% with pseudomyxoma ovarii vs. 13% without, P<0.0001), CDX2 positivity (79% vs. 0%, P<0.0001), and villin positivity (57% vs. 5%, P=0.0009). A subset of mucinous tumors associated with mature cystic teratomas exhibiting morphologic and immunohistochemical features of lower intestinal tract-type mucinous tumors may be teratomatous in origin. In practice, the more common diagnosis of secondary involvement by a lower intestinal tract mucinous tumor should be addressed in the pathology report and in subsequent clinical evaluation; interpretation as a true primary ovarian mucinous tumor of teratomatous origin can be considered as an alternative diagnosis when evaluation and follow-up fail to identify a nonovarian source of the mucinous tumor. Those tumors having CK7 expression with or without CK20 expression may be derived from upper gastrointestinal tract-type or sinonasal-type teratomatous elements but could be independent tumors of surface epithelial-stromal origin.

Recent Advances in the Pathology and Classification of Ovarian Germ Cell Tumors

In recent years, our knowledge of ovarian germ cell tumors has increased, and their classification has evolved. The introduction of cisplatin-based chemotherapy and the discovery of tumor markers, including alpha-fetoprotein and human chorionic gonadotropin, have dramatically changed the clinical outlook for most of these patients. In this review, recent advances in the classification and pathology of ovarian germ cell tumors are discussed. Where appropriate, comparisons are made with testicular germ cell tumors. The last section of the article discusses the pathogenesis of germ cell tumors. This review will emphasize the articles written in the last 10 years and those that have significantly advanced our knowledge of germ cell tumors in past decades.

Glial implants in gliomatosis peritonei arise from normal tissue, not from the associated teratoma

Metaplasia of subcoelomic mesenchyme has been implicated, but not proven, in the pathogenesis of common gynecological diseases such as endometriosis and rarer entities such as leiomyomatosis peritonealis disseminata and gliomatosis peritonei (GP). GP is associated with ovarian teratomas and is characterized by numerous peritoneal and omental implants composed of glial tissue. Two theories to explain the origin of GP have been proposed. In one, glial implants arise from the teratoma, whereas in the other, pluripotent Müllerian stem cells in the peritoneum or subjacent mesenchyme undergo glial metaplasia. To address the origin of GP, we exploited a unique characteristic of many ovarian teratomas: they often contain a duplicated set of maternal chromosomes and are thus homozygous at polymorphic microsatellite (MS) loci. In contrast, DNA from matched normal or metaplastic tissue (containing genetic material of both maternal and paternal origin) is expected to show heterozygosity at many of these same MS loci. DNA samples extracted from paraffin-embedded normal tissue, ovarian teratoma and three individual laser-dissected glial implants were studied in two cases of GP. In one case, all three implants and normal tissue showed heterozygosity at each of three MS loci on different chromosomes, whereas the teratoma showed homozygosity at the same MS loci. Similar results were observed in the second case. Our findings indicate that glial implants in GP often arise from cells within the peritoneum, presumably pluripotent Müllerian stem cells, and not from the associated ovarian teratoma. This finding has important implications for more common gynecological entities with debatable pathogenesis, such as endometriosis, by definitively demonstrating the metaplastic potential of stem cells within the peritoneal cavity.