Mediastinal germ cell tumour associated with malignant histiocytosis and high rubella titres

Primary germ cell tumours of the mediastinum: A review with emphasis on diagnostic challenges

This article will review current aspects of the histopathological, immunohistochemical and molecular analysis of primary mediastinal germ cell tumours (PMGCTs) as well as their aetiological, epidemiological, clinical and therapeutic features. PMGCTs represent an important differential diagnosis in the spectrum of mediastinal tumours, and their diagnosis is usually made on small tissue samples from core needle biopsies in combination with diagnostic imaging and serum tumour markers. As in lymphomas, a small biopsy is often the only viable tumour sample available from these patients, as they receive chemotherapy prior to eventual surgical resection. Pathologists therefore need to apply an efficient combination of immunohistochemical markers to confirm the diagnosis of a PMGCT and to exclude morphological mimics.

Mediastinal endodermal sinus tumor associated with fatal hemophagocytic syndrome

The association of endodermal sinus tumor, known also as yolk sac tumor, of the mediastinum with hemophagocytic syndrome is exceedingly rare with only a few cases on record. We report a 24-year-old male who had a large mediastinal germ cell tumor, proven to be an endodermal sinus tumor on biopsy. The patient developed pancytopenia and coagulopathy related to associated hemophagocytic syndrome, with a fatal outcome. A brief review of the relevant literature is presented as well.

Mediastinal germ cell tumors

Germ Cell Tumors (GCT) represent an important group of mediastinal tumors. Because of genetic characteristics and behavior have been divided in prepubertal and postpubertal tumors, and their origin remains controversial. The genetic changes are diverse, but the most frequent is i (12p), and can be associated to gonadal disgenesis. Histological classification is similiar to that of gonadal tumors and all histological types have been described in the mediastinum. Teratomas may undergo malignant transformation with the emergence of somatic tumors such as haematological malignancies, sarcomas, carcinomas and neurogenic tumors, and such transformation may occur in the primary site or in the metastases. Prognostic factors in mediastinal germ cell tumors include: age of the patient, histological type, distant metastases, stage, status of resection, level of serum tumor markers and proliferation markers. Immunohistochemistry is especially useful when the primary GCT is occult, to separate types of immature GCT, and to determine the lineage of malignant transformation which may be important to design treatment strategies.

Hematologic disorders associated with primary mediastinal nonseminomatous germ cell tumors

BACKGROUND

The association between primary germ cell tumors of the mediastinum (the space between the lung pleura that contains the heart and other chest viscera) and hematologic malignancies has been described by retrospective analysis of patients treated at individual clinical centers. To better characterize the risk of hematologic disorders in patients with extragonadal germ cell tumors and to describe the clinical and biologic features of the disorders, we studied an unselected population in a large, international, multicenter database.

METHODS

Six hundred thirty-five patients treated at 11 centers in the United States and Europe from 1975 through 1996 were evaluated retrospectively.

RESULTS

A hematologic disorder was observed in 17 patients with germ cell tumors. All cases developed among the 287 patients with primary mediastinal nonseminomatous germ cell tumors, giving an incidence rate in this group of 2.0% (95% confidence interval [CI] = 1.1%-3.1%) per year over a median follow-up time of 3 years. The risk of developing hematologic disorders was statistically significantly increased in patients with primary mediastinal nonseminomatous germ cell tumors in comparison with the age-matched general population (standardized incidence ratio = 250; 95% CI = 140-405). The median time to onset of hematologic neoplasia was 6 months (range, 0-47 months), and the median survival after diagnosis of the hematologic disorder was 5 months (range, 0-16 months) (two-sided P<.0001, comparing survival from the time of diagnosis of the germ cell tumor of patients with and without hematologic disorders).

CONCLUSION

In our study, approximately one in 17 patients with primary mediastinal nonseminomatous germ cell tumors was affected by a hematologic disorder, whereas no cases were seen among 334 patients with other extragonadal germ cell tumors. The hematologic disorder had a statistically significant impact on prognosis, with none of the 17 reported patients surviving for more than 2 years.

Mediastinal non-seminomatous germ cell tumours: their association with non-germ cell malignancies

Mediastinal non-seminomatous germ cell tumors are unique tumors in that they are associated with both sarcomatous and hematologic neoplasms. This paper relates our experience at Indiana University with these tumors, and discusses the possible mechanisms of their occurrence, especially with respect to the hematologic neoplasms.

The unique association of malignant histiocytosis and a primary gonadal germ cell tumor

Previous reports of the association between hematologic malignancies and germ cell tumors have been limited to patients with nonseminomatous tumors, exclusively of mediastinal origin. Among the various hematologic disorders, a large proportion have involved histiocytic tumors, either acute monocytic leukemia or malignant histiocytosis. We now report the first case of simultaneously occurring malignant histiocytosis and testicular embryonal carcinoma. The patient, an 18-year-old male, presented with hepatosplenomegaly due to malignant histiocytosis and was found on further evaluation to have a stage I testicular cancer consisting of teratocarcinoma with endodermal sinus elements. Despite aggressive chemotherapy, the patient died of malignant histiocytosis 6 months after the original diagnosis. The autopsy revealed widespread organ involvement with malignant histiocytosis and no evidence of residual germ cell tumor. This case demonstrates that germ cell tumors associated with hematologic malignancy do not arise solely in extragonadal sites.

Hematologic neoplasia associated with primary mediastinal germ-cell tumors

Between September 1983 and December 1988, we observed 16 cases of hematologic neoplasia associated with mediastinal germ-cell tumors. Twenty-eight similar cases have been reported in the literature. A review of the clinical and cytogenetic details in these patients suggests that the hematologic neoplasia is not the result of cisplatin-based chemotherapy of the mediastinal germ-cell cancer. This syndrome was found only in patients with nonseminomatous mediastinal germ-cell tumors, particularly those with serologic or histologic evidence of yolk-sac elements. The two most common hematologic neoplasms seen in this syndrome were acute megakaryoblastic leukemia and malignant histiocytosis. Consistent cytogenetic abnormalities have not yet been identified, but the finding of the marker chromosome isochromosome (12p) in the mediastinal germ-cell tumor and associated leukemic blasts in one patient suggests that these tumors may arise from a common progenitor cell.