Rhabdomyosarcoma and benign teratoma

Embryonal rhabdomyosarcoma arising from a mediastinal teratoma: an unusual case report

We report an unusual case of 9.5-cm-sized embryonal rhabdomyosarcoma arose from a mediastinal mature teratoma in a 46-yr-old man. A man presented with chest trauma as a result of an accident at 10 September 2011. On chest X-ray, an anterior mediastinal mass was detected. To obtain further information, chest computed tomography (CT) with contrast enhancement was performed, revealing an anterior mediastinal mass. Complete surgical excision was performed and entire specimen was evaluated. Pathologic diagnosis was embryonal rhabdomyosarcoma arising in mature cystic teratoma. After surgical excision, two cycles of dactinomycin-based chemotherapy were performed. Lung metastasis was detected on follow up CT in September 2012, and wedge resection was performed. Pathological finding of the lung lesion showed same feature with that of primary rhabdomyosarcoma.

Collision tumor of the mediastinum: a rare entity

A collision tumor is a rare entity consisting of 2 different tumors that, because of proximity, merge together. The diagnosis of a collision tumor requires that the 2 tumors be histologically distinct. This phenomenon has been described mostly at the esophagogastric junction, where a squamous cell carcinoma of esophageal origin collides with a gastric adenocarcinoma. The present case is of 2 histologically distinct tumors with aggressive features occurring at the mediastinum.

Extragonadal germ cell tumors: a review with emphasis on pathologic features, clinical prognostic variables, and differential diagnostic considerations

Extragonadal germ cell tumors (GCTs) are relatively uncommon, but represent 1% to 5% of all GCTs. Their morphology varies widely and includes mature teratoma, immature teratoma, seminoma, yolk sac tumor, embryonal carcinoma, choriocarcinoma, and mixed GCTs. Noncentral nervous system extragonadal GCTs are found in a variety of anatomic locations, but most commonly affect the mediastinum and sacrococcygeal region. Predicting behavior in these tumors can be confusing because it is based on a combination of varying factors including patient age, histologic subtype, anatomic site, and clinical stage. This review attempts to dissect these issues by separating the discussion into 3 age groups: neonatal (congenital), children (prepubertal), and adult (postpubertal). Within each individual age group, we cover the significance of anatomic site, morphology, and staging parameters. In addition, we discuss the spectrum of associated secondary malignancies and their impact on patient outcome. Finally, we provide a detailed survey of differential diagnostic considerations grouped by anatomic site.

Collision tumors in children: a review of the literature and presentation of a rare case of mesoblastic nephroma and neuroblastoma in an infant

A mass made up of 2 distinct synchronous primary malignant tumors is a rare event in adults, and exceedingly so in children. Such lesions have been called collision tumors. Reported here is an infant who was found to have a collision tumor comprised of a neuroblastoma and a congenital mesoblastic nephroma, in contiguity, in the right kidney. This is the first report of a collision tumor in an infant. This also is the first report of a synchronous occurrence of a neuroblastoma and a congenital mesoblastic nephroma. The authors present this case and discuss the available literature.

Rhabdomyosarcomas of the anterior mediastinum: report of four cases unassociated with germ cell, teratomatous, or thymic carcinomatous components

Four cases are presented of primary anterior mediastinal tumors in young adults that were characterized by solid, infiltrative lesions showing histologic and immunohistochemical features of rhabdomyoblastic differentiation. The patients were three men and one woman between 19 and 27 years of age (mean age, 23 years). All patients presented with symptoms referable to their tumors, including cough, chest pain, dyspnea, and left-sided pleural effusion. Grossly and radiographically, the lesions were characterized by their solid, infiltrative appearance. Histologically, two cases corresponded to the solid variant of alveolar rhabdomyosarcoma, one case was an embryonal rhabdomyosarcoma with a predominant spindle cell component, and the remaining case showed the features of a pleomorphic rhabdomyosarcoma. No glandular, epithelial, or other component could be identified in any of the tumors on extensive sampling. Immunohistochemical studies showed positive staining of the tumor cells with actin, desmin, and vimentin antibodies, with focal positivity for myoglobin in three cases and focal positive staining with S-100 protein in one case. Stains for low and high molecular weight keratin, carcinoembryonic antigen, alpha-fetoprotein, human chorionic gonadotropin, placental alkaline phosphatase, leukocyte-common antigen, and neuron-specific enolase were negative. All patients experienced rapid recurrence and metastases within the first 6 months after diagnosis. Three patients died within this period due to their tumors; the fourth patient has been lost to follow-up. Pure primary rhabdomyosarcomas of the anterior mediastinum are highly aggressive neoplasms that should be distinguished from germ cell, teratomatous, or carcinosarcomatous tumors with a focal rhabdomyoblastic component.

Poor prognosis of mediastinal germ cell cancers containing sarcomatous components

Fifteen patients with biopsy-proven mediastinal germ cell tumors treated with platinum-based chemotherapy were reviewed. They had a period of 4 to 6 weeks between the onset of symptoms and diagnosis. Four patients had sarcomatous elements in their tumor in association with common germ cell histologies. The sarcomatous components consisted of one angiosarcoma, one rhabdomyosarcoma, and two cases with mixed angiosarcoma and rhabdomyosarcoma. All patients with sarcomatous elements died; the median survival for these patients was 9 months. In contrast, six (54%) of the patients who did not have sarcomatous elements in their tumor are long-term disease-free survivors 5 to 8 years after diagnosis. The occurrence of sarcomatous elements in a mediastinal germ cell tumor is a poor prognostic sign, and therapy should be oriented to include drugs and regimens that may be effective against sarcoma.

Dysgerminoma of the ovary with rhabdomyosarcoma. Report of a case

A 14-year-old girl with a large left ovarian mass underwent excision of the tumor which on histologic examination revealed dysgerminoma mixed with elements of rhabdomyosarcoma. A subsequent staging laparotomy revealed a solitary 1-cm nodule along the pelvic wall. This was composed of rhabdomyosarcoma. Review of literature revealed that soft tissue sarcomas of several types may on occasion be seen in association with gonadal and extragonadal mixed germ cell tumors or in spermatocytic seminoma of the testis. However, no previously published report of a sarcoma arising in a pure dysgerminoma was found in the literature.