CT and MRI features of intracranial germ cell tumors

Germ cell tumours of the central nervous system: treatment consideration based on 111 cases and their long-term clinical outcomes

Germ cell tumours (GCTs) of the central nervous system (CNS) encompass various histological subtypes, and their optimal management has been the subject of debate. To indicate a better management strategy for each subtype, we analysed the records of 111 patients (median age 14 years), who underwent treatment since 1970. With a median follow-up duration of 86 months, the probability of surviving 5 years was: 96% for pure germinoma patients, 100% for mature teratoma, 67% for immature teratoma and 69% immature teratoma mixed with germinoma. The probability of cause-specific progression of germinomas producing human chorionic gonadotropin (HCG) was higher than that of non-producing germinomas (P < 0.01). GCTs that included a highly malignant component, such as embryonal carcinoma or yolk sac tumour, exhibited a poor prognosis with 38% chance of 5-year survival. Late adverse effects of therapy included stroke, secondary malignancy and cognitive, endocrinological, auditory and visual dysfunctions. Of 85 survivors with a median follow-up period of 99 months, 58 patients needed hormone replacement therapy, 26 patients showed poor performance status and, to date, only 1 patient has fathered children. Because the outcomes varied widely for each subtype, the traditional categories, that is, germinoma and non-germinomatous GCT as an extrapolation from the gonadal GCTs, are not suitable for appropriately selecting therapeutic regimen for CNS GCTs.

Management of primary intracranial germinomas: diagnostic surgery or radical resection?

Because intracranial germinomas are readily curable with radiation and chemotherapy or radiation therapy alone, the role of radical surgery has become debatable. This study assesses the optimum degree of surgical resection for intracranial germinomas. Twenty-nine patients who underwent surgery for germinoma were retrospectively analyzed (male/female ratio 27:2, median age 18 years). Among these 29 patients there were 10 solitary pineal, seven solitary neurohypophyseal/hypothalamic, and 12 multifocal or disseminated tumors. Biopsy samples were obtained in 16 patients (stereotactically in eight, transsphenoidally in four, and via frontotemporal craniotomy in four). Partial resection was attained in five patients (via a frontotemporal approach in three and occipitotranstentorially in two). Gross-total resection was achieved via an occipitotranstentorial route in eight patients with pineal masses. After surgery, 10 patients were treated with radiotherapy alone, and 19 received radiation and chemotherapy; complete remission was achieved in all 29 patients. The overall tumor-free survival rate was 100% at a median follow-up period of 42 months. There was no significant difference in outcome related to the extent of surgical resection. Postoperative neurological improvement was seen in only two patients, whereas transient postoperative complications, mainly upgaze palsy, were observed in six. One patient experienced a slight hemiparesis, bringing the surgical morbidity rate to 3% (one of 29). It is concluded that radical resection of intracranial germinomas offers no benefit over biopsy. The primary goal of surgery should be to obtain a sufficient volume of tumor tissue for histological examination. If there is strong evidence of germinoma on radiological studies, biopsy samples should be obtained. When a perioperative histological diagnosis of pure germinoma is made during craniotomy, no risk should be taken in continuing the resection.

Primary intracranial germ cell tumors: a clinical analysis of 153 histologically verified cases

The authors analyzed 153 cases of histologically verified intracranial germ cell tumors. The histological diagnosis was germinoma in 63 patients (41.2%), teratoma in 30 (19.6%), and other types of tumors in 60 patients (39.2%). The patients were treated by a consistent policy of surgical removal with histological verification followed by radiation therapy with or without chemotherapy. The 10- and 20-year survival rates of patients with pure germinoma were 92.7% and 80.6%, respectively. The 10-year survival rates of patients with mature teratoma and malignant teratoma were 92.9% and 70.7%, respectively. Patients with pure malignant germ cell tumors (embryonal carcinoma, yolk sac tumor, or choriocarcinoma) had a 3-year survival rate of 27.3%. The mixed tumors were divided into three subgroups: 1) mixed germinoma and teratoma; 2) mixed tumors whose predominant characteristics were germinoma or teratoma combined with some elements of pure malignant tumors; and 3) mixed tumors with predominantly pure malignant elements. The 3-year survival rates were 94.1% for the first group, 70% for the second group, and 9.3% for the third group, and the differences were statistically significant. Twenty-six patients with malignant tumors received chemotherapy that consisted of cisplatin and carboplatin combinations with or without radiation therapy. However, chemotherapy was not significantly more effective than radiation therapy alone. From these treatment results, the authors classified tumors into three groups with different prognoses and proposed a treatment guideline appropriate for the subgroups.

Prognosis of intracranial germinoma with syncytiotrophoblastic giant cells treated by radiation therapy

PURPOSE

The limited information in the literature suggests that intracranial germinoma with syncytiotrophoblastic giant cells (STGC) producing human chorionic gonadotropin (HCG) is associated with a higher recurrence rate compared with pure germinoma producing no HCG. To determine whether the poorer prognosis for germinoma with STGC is an inevitable finding, we retrospectively analyzed data for our patients.

METHODS AND MATERIALS

Data were analyzed for 44 patients who had pretreatment examination of HCG titers in the serum and/or cerebrospinal fluid (CSF) and underwent radiotherapy between 1978 and 1993. The diagnosis of germinoma was made histologically in 19 patients and clinically in 25 according to the established criteria. The treatment volume was the primary tumor site in 9 patients, the cerebrospinal axis in 29, and other in 6. The median follow-up period was 90 months.

RESULTS

Twenty (45%) of the 44 patients had elevated HCG titer. The abnormal HCG levels ranged from 4.9 to 189 mIU/ml (median: 18 mIU/ml) in serum and 8.2 to 660 mIU/ml (median: 26 mIU/ml) in CSF. No difference was found between the two groups in any patient or treatment characteristics including tumor size and incidence of CSF dissemination. The mean radiation dose to the primary tumor site was 46.4 Gy for pure germinoma and 47.5 Gy for germinoma with STGC. The 10-year survival and relapse-free survival rates were both 100% for the patients with germinoma with STGC and both 89% for those with pure germinoma. Among these patients, only two with pure germinoma developed recurrence.

CONCLUSIONS

Our data suggest that the prognosis of intracranial germinoma with STGC treated with adequate radiation therapy does not differ from that of pure germinoma. Our current policy of delivering 40-45 Gy for tumors < 4 cm in diameter seems to be a reasonable treatment for germinoma with STGC.

Mixed germ-cell tumor of the brain. Pathologic study of six autopsy cases

Intracranial mixed germ-cell tumors are rare. We describe the findings from six autopsies of patients with these tumors. The patients were all young at presentation (mean age, 16 years), and five of the six were male. Headache, vomiting, polyuria and diplopia were common symptoms. Radiographic evaluation demonstrated a mass on the midline of the brain. The patients were treated mainly with radiation, but survival (mean, 3.7 years) was not as long as predicted. At autopsy, the tumors occupied most of the ventricular spaces, and ranged from being well-circumscribed to invasive. All tumors contained both germinoma components and nongerminomatous germ-cell tumor components. Because the distribution of these components was not homogenous, at least two sections were necessary for the diagnosis. Immunoreactivity for placental alkaline phosphatase was found in all tumors. Immunostaining for human chorional gonadotropin, alpha-fetoprotein and carcinoembryonic antigen was usually associated with abnormally high serum levels of these tumors markers in life. A number of the cells in both kinds of tumor components expressed proliferating cell nuclear antigen, probably reflecting the intense malignant potential.