Primary germ cell tumor of the anterior mediastinum with features of endodermal sinus tumor. (Mesoblastoma vitellinum)

Primary mediastinal germ cell tumors

Mediastinal germ cell tumors share similar histopathological, immunohistochemical, and molecular features with their counterparts in the gonads. Therefore, proper clinical and radiological evaluation of patients with an anterior mediastinal mass becomes essential in the final interpretation of these tumors. The gold standard for the diagnosis of these tumors remains histopathological evaluation. However, immunohistochemical stains and molecular studies also provide an aid in cases in which the histology is not typical. It is also important to keep in mind that a small mediastinoscopic biopsy may not be representative of the entire neoplasm. In this review, we will provide our perspective regarding histopathological diagnosis, staging, immunohistochemical and molecular profile, and briefly family of tumors address pertinent epidemiological, clinical and treatment options. However, the main emphasis is to review the process of pathological assessment in pre and post-treated tumors. Knowledge of the different growth patterns and histological associations is important, mainly when confronted with mediastinoscopic biopsies, which ultimately will determine treatment options.

A primary mediastinal germ cell tumor of yolk sac type: case report

The mediastinal malignant germ cells tumor represents less than 0.5% of thoracic tumors, although the mediastinum is one of the main extragonadic locations of these tumors. In the majority of cases, young people are those most affected. The prognosis of mediastinal malignant germ cells tumors is poor, especially non-seminomatous germ tumors. In this article, we report a rare case of a young 19-years-old patient treated for a mediastinal germ cell tumor of yolk sac. The patient presented a chest pain; the chest computed tomography (CT) showed a right paramedian mediastinal mass with a pleural effusion associated with supraclavicular and cervical lymph nodes. Biopsy revealed a non-seminomatousgerm cell tumor of yolk sac. The exams showed elevated alpha-fetoprotein (AFP), without any meaningful elevation of other serictumor markers. The patient received 4 cycles of chemotherapy based on etoposide, ifosfamide and platinum salts then a complete excision of the mass.

Yolk sac primary tumor of mediastino: a rare case in a young adult

Germ cell tumors are rare neoplasms that mostly occur in the gonads, although they can also affect other body sites, especially the anterior mediastinum (50 to 70% of all extragonadal germ cell tumors). We report a case of a primary mediastinal yolk sac tumor, a rare and aggressive germ cell tumors subtype. This was a 38-year-old man who was admitted to Hospital do Servidor Público Estadual “Francisco Morato de Oliveira”, complaining about dyspnea and dry cough for 1 year. The computed tomography scan of his chest revealed a large mass in the anterior mediastinum with heterogeneous enhancement to the contrast associated with pleural effusion. There were also high serum levels of alpha-fetoprotein. After neoadjuvant chemotherapy, the patient underwent surgical resection of the mass, followed by pathological examination, which confirmed a primary mediastinal yolk sac tumor, a nonseminomatous subtype of germ cell tumors. Primary mediastinal yolk sac tumors have poor prognosis, despite advances in therapy with surgical resection and cisplatin-based chemotherapy. This poor prognosis is due to the degree of invasion and unresectability in most patients by the time of the diagnosis.

Successful radiotherapy in postoperative recurrence of a primary mediastinal yolk sac tumor: A case report

A woman in her 60s was evaluated for anterior chest pain. Computed tomography (CT) revealed a 50 mm mass with irregular contrast enhancement in the anterior mediastinum. α‐fetoprotein (AFP) level was elevated to 1188 ng/mL. A germ cell tumor was diagnosed, mostly comprising of a yolk sac tumor (YST). Two courses of chemotherapy with cisplatin (CDDP) and etoposide (VP16) were administered and surgical tumor resection was then performed. The final diagnosis was YST. CDDP and VP16 were continued postoperatively; however, because the AFP level increased about six months after surgery, the chemotherapy regimen was altered to bleomycin and CPT‐11. As the AFP again increased and a CT scan revealed tumor re‐enlargement, recurrent YST was diagnosed and radiotherapy was administered. The patient received a total of 60 Gy (2 Gy per fraction). The tumor started to shrink during radiotherapy and AFP levels decreased. By one month post‐radiotherapy, AFP levels had normalized and the tumor had disappeared. As of six years after radiotherapy, the patient remains alive without recurrence. Mediastinal YSTs are rare, and treatment usually includes surgery and preoperative and postoperative chemotherapy with cisplatin‐based regimens. Successful treatment with radiotherapy has occasionally been reported. Our patient showed recurrence of a YST after surgery and chemotherapy, but achieved long‐term survival after radiotherapy. Few patients with YST have undergone radiotherapy, but this approach was successful in our patient. In cases of postoperative recurrent YST resistant to chemotherapy, radiotherapy, together with salvage surgery, may offer a valuable option.

Radical surgical resection for giant primary mediastinal endodermal sinus tumour with pulmonary metastasis after chemotherapy: can be curative

Primary non-seminomatous germ cell tumours of anterior mediastinum are uncommon. Endodermal sinus tumour of the anterior mediastinum (yolk sac) is a rare but lethal neoplasm. We present a case of an 18-year-old man who presented with chest pain, cough and haemosputum with markedly raised serum α-fetoprotein (AFP) levels above 112,000 ng/mL. Chest roentgenogram and CT showed a giant anterior mediastinal mass. CT guided biopsy revealed a diagnosis of endodermal sinus tumour. After the completion of chemotherapy, extensive surgical resection was carried out along with the right lung metastastectomy. Five years postresection follow-up the patient is disease free with normal serum tumour markers. This is the longest survival ever reported of such tumours with highest AFP level (>112,000 ng/mL) and lung metastasis.

Hepatoid yolk sac tumors of the mediastinum: a clinicopathologic and immunohistochemical study of four cases

Four cases of primary hepatoid yolk sac tumors of the anterior mediastinum are described. The patients were all men between the ages of 26 and 40 years (median 33). Clinically, they all presented with a history of shortness of breath and chest pain of several weeks' duration. None of the patients had a history of germ cell tumor elsewhere or evidence of any hepatic abnormality. Grossly, all the tumors were described as large mediastinal masses that impinged on adjacent structures. Histologically, they were characterized by sheets of medium-sized, round to polygonal neoplastic cells with moderate amounts of eosinophilic cytoplasm and round to oval nuclei with prominent nucleoli. The cellular proliferation was homogeneous and displayed moderate cellular atypia and scattered mitotic activity. All the tumors showed focally the presence of more conventional areas of yolk sac tumor, with islands of tumor cells showing a reticular pattern of growth admixed with scattered intra- and extracellular hyaline globules and occasional Schiller-Duval bodies. Immunohistochemical studies showed strong positivity of the tumor cells for alpha-fetoprotein in both components of the lesions. Follow-up information was available in three patients, all of whom developed lung metastases within a year after initial diagnosis. Two of these patients died of tumor within the same period, whereas a third patient has been lost to follow-up. The present cases illustrate an unusual histologic pattern of yolk sac tumor in the mediastinum and highlight the importance of considering this tumor in the differential diagnosis of lesions showing a hepatoid pattern of growth in the mediastinal area.

Yolk sac tumors of the mediastinum with prominent spindle cell features: a clinicopathologic study of three cases

Three cases of primary mediastinal yolk sac tumors with prominent spindle cell features are presented. The patients were three men 24-34 years of age (mean 29). Clinically, two patients presented with symptoms of chest pain and cough; no clinical information was provided for the third patient. Grossly, the tumors were described as large mediastinal masses, with a hemorrhagic and necrotic cut surface. Histologically, the tumors were characterized by a predominantly atypical spindle cell proliferation admixed with areas that showed focally the characteristic reticular growth pattern of yolk sac tumors, with the presence of Schiller-Duval bodies and intra- and extracellular hyaline globules. Immunohistochemical studies performed in one case showed positive staining for keratin and alpha-fetoprotein in both the spindle cell and reticular components of the tumor. Follow-up information was obtained in two patients; they both died of tumor with metastases to the lungs 1 year after initial diagnosis. The present cases expand the spectrum of histopathologic growth patterns that may be observed in yolk sac tumors of the mediastinum and stress the issue of careful sampling and evaluation of mediastinal neoplasms for arriving at the correct diagnosis.

Primary mediastinal choriocarcinomas: a clinicopathologic and immunohistochemical study of eight cases

Primary choriocarcinoma of the anterior mediastinum is by far the rarest and most controversial form of extragonadal germ cell tumor. A clinicopathologic study of eight primary mediastinal neoplasms bearing the histopathologic and immunohistochemical features of choriocarcinoma is presented. The patients were all men between the ages of 21 and 63 years (mean, 42 years). Clinical symptoms included shortness of breath, chest pain, cough, and superior vena cava syndrome; one patient also had gynecomastia. All patients presented with large anterior mediastinal masses on chest radiographs that measured an average of 10 cm in greatest diameter. Grossly, the tumors were described as large, soft, extensively hemorrhagic, and with foci of necrosis. Histologically, they were characterized by a dual cell population composed of cytotrophoblastic cells with uniform, round nuclei, clear cytoplasm, and prominent nucleoli admixed with large, multinucleated syncytiotrophoblastic cells with bizarre nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Immunohistochemically, the tumors were notable for strong keratin and beta-human chorionic gonadotropin (HCG) positivity. Seven patients presented at the time of diagnosis with thoracic and extrathoracic (liver, adrenal, kidney, and spleen) metastases. In one case, the tumor was entirely confined to the mediastinum. All patients died over a period of 1 to 2 months. Complete autopsies were performed in all cases; none of the patients showed evidence of a testicular tumor or scar after thorough examination of the testes on serial sectioning. The present cases demonstrate the widespread distribution of germ cells in the human body and lend further support to the existence of primary extragonadal choriocarcinoma arising in the thymic region.

Yolk sac tumour of the anterior mediastinum

Two cases of yolk sac tumour involving the anterior mediastinum in two young Chinese males are described. The tumour in both patients could only be partially debulked, and they died within a few months despite multiple chemotherapy. The importance of early diagnosis, radical surgery and aggressive combination chemotherapy in prolonging the period of survival of such patients is emphasized. Serum alpha-fetoprotein should be determined in every patient, especially a young male adult, who presents radiologically with a hilar mass.

Experience with the management of primary endodermal sinus tumor of the mediastinum

Ten male patients with extensive primary endodermal sinus tumor of the mediastinum were treated with chemotherapy (with or without surgical excision and radiation therapy) between 1977 and 1985. Three patients, treated with cyclophosphamide-vincristine-based chemotherapy, died 1.5, 2.5, and 6.0 months, respectively, after initial diagnosis. Of the seven patients treated with cisplatin-based chemotherapy, one patient died of septicemia at 2.5 months after diagnosis and was disease-free at autopsy examination. Three other patients died of progressive disease at 7.0, 13.0, and 14.0 months, respectively. The three survivors remain alive at 17.0, 31.0, and 40.0 months from diagnosis; all are without evidence of disease. Of the three patients who underwent excision of the residual mediastinal tumor after cisplatin-based chemotherapy, persistent local disease was found in two patients. One of these two patients died of recurrent disease. All surviving patients had surgical resection of the tumor either before or after cisplatin-based chemotherapy, with or without radiotherapy and the timing of therapeutic interventions was guided by changes in the serum alpha-fetoprotein concentrations after initial therapy and during follow-up. Our experience suggests that the optimal management of patients with primary mediastinal endodermal sinus tumor requires an aggressive multidisciplinary approach guided by the extent of the tumor and the serum tumor marker levels.

Endodermal sinus tumor of the mediastinum. A report of seven cases and review of the literature

Primary mediastinal endodermal sinus tumor is rare, and to date only 49 cases have been described in the English-language literature. Seven new cases are reported. Light microscopic examination showed characteristic features including papillary, reticular, tubular and solid growth patterns, complete or incomplete Schiller-Duval bodies and intracellular or extracellular periodic acid-Schiff-positive material. Immunohistochemical studies showed alpha-1-antitrypsin in seven, alpha-fetoprotein in seven, keratin in six, and carcinoembryonic antigen in four cases. The beta subunit of human chorionic gonadotropin, albumin, fibronectin, and transferrin were not found in any case. Electron microscopic studies performed in four cases showed intracellular and extracellular basement membrane-like material, multiple large multivesicular bodies, desmosomes and microvilli. Mediastinal endodermal sinus tumor can and must be differentiated from poorly differentiated adenocarcinoma metastatic or extending to the mediastinum because of the distinctly different prognoses and therapies. In spite of modern chemotherapy, the prognosis of mediastinal endodermal sinus tumor remains poor. The single most important prognostic indicator is whether the tumor mass can be completely excised before or after chemotherapy.

Malignant germ cell tumor of the anterior mediastinum with leukemia-like infiltration

We present here a rare autopsy case of malignant germ cell tumor with leukemia-like infiltration of the anterior mediastinum in a 35-year-old male. Chest X-rays revealed an abnormal mediastinum, which was diagnosed as thymoma. During the course of treatment, huge abnormal cells 40-50 mu in size were found in the peripheral blood smear and disseminated bone metastasis of the malignant thymoma was suspected. The tumor was resistant to both chemotherapy and radiotherapy. The patient died of respiratory failure. The autopsy disclosed a huge tumor measuring 24 X 13 X 10 cm in the anterior mediastinum. Histological findings of the tumor revealed cells which had spread to almost all organs, indicating leukemia-like infiltration. This pattern of metastasis has been reported in the cancer of non-hematologic origin under the term "carcinocythemia (CCA)". To our knowledge, the present case is the first report of a leukemia-like infiltration in case of malignant germ cell tumor. Careful serial section revealed no primary foci in either testis.

Anterior mediastinal endodermal sinus (yolk sac) tumor in a female infant

The first known case of primary anterior mediastinal endodermal sinus (yolk sac) tumor in a female patient, occurring in a 20-month-old infant, is reported. The child presented with cough, fever, and listlessness. Chest x-ray revealed a right anterior mediastinal mass. At thoracotomy a large anterior mediastinal tumor extending from the neck to the diaphragm was found, and was almost totally resected. Microscopically, the tumor displayed many of the histologic patterns observed in EST. Other neoplastic germ cell elements were not identified. The ultrastructural and immunohistochemical findings further confirmed the diagnosis. Serum alpha-fetoprotein (AFP) level, determined during surgery, was elevated to 65,200 ng/ml, whereas serum beta-human chorionic gonadotropin level was normal. Postoperatively, combination chemotherapy consisting of vinblastine, bleomycin, cisplatin, dactinomycin, cyclophosphamide, and doxorubicin was administered with a maintenance program. After 18 weeks on this regimen all the findings were normal, including serum AFP level. The child is well and disease-free 25 months after diagnosis.

Endodermal sinus tumor of the stomach

This is a case report of an endodermal sinus tumor arising in the stomach of a 72-year-old Japanese woman. The tumor showed Borrmann 2 type at the mucosal surface, and the main mass occupied the subserosal layer with outgoing extension. Microscopically, the tumor showed typical characteristics of the endodermal sinus tumor, associated with embryonal carcinoma, poorly differentiated adenocarcinoma and well differentiated tubular adenocarcinoma. Alpha-fetoprotein was detected in the serum of the patient by radioimmunoassay and within tumor tissue by immunohistochemical techniques. Ultrastructurally, a characteristic basement membrane-like material has been identified in intercellular spaces.

Endodermal sinus tumor of the mediastinum

Endodermal sinus tumor (EST) of the mediastinum is a rare germ-cell neoplasm affecting mainly young adult males. Ten patients with EST were treated with a multimodality approach that included surgery, chemotherapy, and radiotherapy. All patients had relapses after achieving a transient response except one who is still in complete remission more than five years following the diagnosis of the disease. Optimal therapy for this neoplasm has yet to be discovered. The disease is a subset of extragonadal germ cell tumors which appears to be lethal in most cases, particularly when the primary tumor is unresectable. The first case of five-year disease-free survival is described.

Endodermal sinus tumor originating in the region of the pineal gland: ultrastructural and immunohistochemical study

This is a case report of an endodermal sinus tumor (EST) arising in the pineal region of a 19-year-old girl (first case studied by electron microscopy). The ultrastructure of the tumor was similar to that of the previously reported cases of EST of ovaries, mediastinum, and sacrococcygeal area. A characteristic basement membrane-like material has been identified within endoplasmic reticulum of tumor cells and in intercellular spaces. Alphafetoprotein has been detected in the spinal fluid of the patient by radioimmunoassays and within tumor tissue by immunohistochemical techniques. Combination therapy consisting of radiation, surgical decompression, chemotherapy (BCNU), and prednisone has been employed in the treatment of this patient without significant benefit. The patient expired three months after the surgery, no autopsy was obtained.

Endodermal sinus tumor of the pineal region: case report and review of literature

This is a case report of an endodermal sinus tumor occurring in the pineal region of a 14-year-old boy who died 4 weeks after surgery and irradiation. Germ cell tumors of this type demonstrate a selective overgrowth of yolk sac endoderm associated with extraembryonic mesoblast and arise preferentially in the gonads of young children. This tumor in the pineal region is rare and carries a grave prognosis as in other extragonadal sites. A summary of previously reported cases is also presented.

Extragonadal endodermal sinus (yolk sac) tumor. Angiographic findings and literature review

The angiographic and pathologic features of an endodermal sinus tumor (EST) arising from the retroperitoneum in a 19-month-old boy are presented. Although rare instances of extragonadal origin of EST have been reported, this is the first detailed description of the angiographic abnormalities. The angiographic appearance was that of a primarily retroperitoneal tumor with parasitized feeding arteries from the liver and right kidney, early filling venous radicles, sinusoidal pooling of contrast material, and inferior vena caval obstruction.

Endodermal sinus tumor: the Stanford experience and the first reported case arising in the vulva

A review of the histology, clinical findings and results of therapy in 9 females with endodermal sinus tumor (EST) is presented. Five patients had histologically pure EST; 4 had EST mixed with other germ cell components. The site of primary tumor was the ovary in 8 of the 9 females; the remaining patient with an extraovarian primary represents the first reported case of EST arising in the vulva. The addition of combination chemotherapy has prolonged survival over historical controls treated with surgery or surgery plus irradiation. Adjuvant chemotherapy appears warranted as treatment for occult metastatic disease; postoperative radiation therapy appears useful in providing local control of primary disease. There is a suggestion of increased sensitivity of EST to combination chemotherapy as compared to other germ cell histologies with which it is commonly admixed.

Primary yolk-sac (endodermal sinus) tumor of the prostate

A primary yolk-sac (endodermal sinus) tumor of the prostate occurring in a 51-year-old man is described, and the difficulties associated with classification of this tumor are discussed. Yolk-sac tumors have been reported to arise in several extragonadal sites, but to our knowledge this is the first documented case of a germinal cell tumor occurring the the prostate. This tumor in extragonadal sites carries a grave prognosis. Despite radical surgery, radiotherapy, and chemotherapy, this patient died 10 months after the tumor was diagnosed.

Endodermal sinus tumor of the mediastinum. Ultrastructural study

This is the eighth case report of an endodermal sinus tumor of the mediastinum (first case studied by electron microscopy). The ultrastructure of the tumor was found to mimic that of the normal yolk sac and was also similar to that of three previously reported cases of endodermal sinus tumor of the ovary, thus confirming the correctness of Teilum's original interpretation of the tumor as arising in germ cells and differentiating towards extraembryonic structures.

Endodermal sinus tumor of the pineal region: case report

This is a case report of an endodermal sinus tumor occurring in the pineal region of a 12-year-old Caucasian boy. Germ cell tumors of this type demonstrate a selective overgrowth of yolk sac endoderm associated with extraembryonic mesoblast and arise perferentially in the gonads of young children. This is the ninth known report of this tumor in the world literature. Its occurrence in the posterior third ventricle again confirms that pineal region germ cell tumors are histologically analogous to germ cell tumors originating in the gonads. A disturbance in the region of the primitive streak is thought to account for the exclusive midline location of this tumor in extragonadal sites. This patient was treated with a combination of vincristine, actinomycin D, and cyclophosphamide, and concomitant cobalt irradiation. For endodermal sinus tumors in the pineal region, this combination appears more effective than previously reported treatment by irradiation alone.

The human yolk sac and yolk sac carcinoma. An ultrastructural study

The ultrastructure of the yolk sac of a 39 day old human embryo was studied. The subcellular organization was suggestive of a highly specialized absorptive function proceeding in an exocelomic-viteline direction. These findings, compatible with intense metabolic activity, are at variance with the concept of rapid involution of the yolk sac following completion of its hemopoietic and angiogenetic functions. The speculation is advanced that a potential avenue exists in the yolk sac whereby maternally derived products encounter fetal endoderm. Ultrastructural features in the normal yolk sac were compared to those existing in a tumor showing the "endodermal sinus" pattern, and reviewed in the light of the pertinent literature. These findings support the concept that attributes an endomesoblastic derivation to such neoplasms.

Gonadal and extragonadal yolk sac carcinomas: a clinicopathologic study of 14 cases

Fourteen cases of yolk sac carcinoma, 10 occurring in gonadal, and four in extragonadal sites, seen at the Indiana University Hospitals from 1949 to 1974, were analyzed with respect to pathologic features, laboratory findings, and clinical course. Their histologic appearance was similar regardless of the site of origin. Two basic histologic types were observed--the more common endodermal sinus pattern and the rare polyvesicular vitelline form. The prognosis is unfavorable, but three of our cases exhibited objective responses to chemotherapy. In our small series, the better prognosis of testicular yolk sac carcinomas in children found by some authors was not evident. Four of the 6 patients with yolk sac carcinoma in which serum alpha-fetoprotein determinations were performed showed positive results. Three of these cases had residual or metastatic disease clinically. The demonstration of alpha-fetoprotein in the serum of patients with yolk sac carcinoma lends further support to the yolk sac origin of these tumors and could also prove to be of prognostic value by indicating the presence of residual or recurrent disease.

Primary retroperitoneal seminoma. Report of a case and review of the literature

A large retroperitoneal seminoma in a 42-year-old man is described, which appears to have arisen as a primary tumor at that site. The mechanism for the development of extragonadal germ cell tumors is discussed, and the criteria for their distinction from metastatic occult or regressed testicular neoplasms are re-emphasized. Awareness by clinicians of this entity may save individuals with this neoplasm from unnecessary orchiectomy.

Primary endodermal sinus (yolk sac) tumor of the liver. First reported case

A primary endodermal sinus (yolk sac) tumor of the liver occurring in an 18-month-old boy is described. Although several examples of extragonadal endodermal sinus tumors have occurred in other sites, this is believed to be the first reported instance of origin in the liver. An additional important feature was the detection of alpha-fetoprotein in a preoperative serum sample. Although no metastases were identified at the time of celiotomy, widespread metastases developed, and he died 6 1/2 months after an extended right hepatectomy was performed. Neither triple chemotherapy nor radiation therapy appeared to deter progressive spread of the neoplasm, although the metastases exhibited some radiosensitivity.

Tumours of the thymic region. Symptomatology, diagnosis, treatment, and prognosis

Fifty-three patients operated on between 1952 and 1971 were originally diagnosed as having thymoma. Re-examination of the material shows that only half of these tumours were true thymomas. The rest were classified as malignant lymphomas, primary and secondary carcinomas, and a few haemangiomas. Half of the patients had symptoms at the time of diagnosis. However, in half of the asymptomatic cases the tumours had penetrated the capsule. Decisive in prognosis are the macroscopic findings around the capsule. Of 33 patients with infiltration of the capsule, 30 had died at the time of investigation. Twenty-five patients died within two years of operation, Twenty-five patients had thymomas, of which 14 were well defined. Twelve patients with thymomas suffered from myasthenia gravis. The treatment of choice of thymoma is total excision, if necessary enbloc, and if there is penetration of the capsule, radiotherapy should be given. None of the patients with a well-defined thymoma had died from their tumour while only two patients with infiltrating thymomas are still alive, Of eight patients with Hodgkin's disease located in the thymus, six had penetration of the capsule, and of these only one patient is still alive. Two patients with well-defined tumours are both alive. The treatment of localized Hodgkin's disease is excision and irradiation. The prognosis for patients with other malignant tumours was bad, the mean time of survival being less than six months.

Mesonephroid tumours of the ovary

Thirty cases of mesonephroid tumour of the ovary were studied. The differential diagnosis is discussed and it is concluded that mesonephroid tumours form a distinct entity. An attempt is made to correlate the histological appearance of the tumours with the clinical course and criteria are suggested which might be a guide to prognosis. Views on histogenesis are discussed but at present there seems insufficient evidence to justify any particular hypothesis.