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1.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
2.
A series of 10 classical testicular seminomas and 10 intracranial germinomas were reviewed and examined using immunohistochemical techniques. In particular, the staining profiles of the tumour cells and the nature of the mononuclear cell infiltrate at the two sites were studied and compared. The tumour cells in eight of the 10 intracranial germinomas and nine of the 10 seminomas exhibited positive staining with placental alkaline phosphatase. Only one intracranial germinoma showed evidence of human chorionic gonadotrophin expression. Tumour cells in all cases at both sites were negative for cytokeratin and vimentin. The lymphocytic infiltrate in both the testicular and intracranial tumours was similar, comprising T-cells and B-cells, the former predominantly. The presence of macrophages and granulomas in tumours at both sites was noted. These findings confirm the high degree of similarity of germinomas of intracranial and testicular origin, and support the hypothesis of a common derivation. We could find no evidence of differentiation of tumour cells at either site.  相似文献   
3.
Background This retrospective study analyzed the outcome in patients with intracranial germ-cell tumors to determine whether tumor response during radiation therapy can predict achievement of primary local control with radiation therapy alone. Methods Between 1983 and 1993, 22 patients with untreated primary intracranial germ cell tumors received a total whole brain radiation dose of between 18 Gy and 45 Gy (mean 31.3 Gy) with or without a localized field of 10 to 36.4 Gy (mean, 22.4 Gy), or local irradiation only (1 patient). In 10 patients with pineal tumor only, who were treated first with radiation therapy, tumor response to radiation therapy was evaluated using computed tomography (CT) (at baseline, and approximately 20 Gy and 50 Gy). Areas of calcification in the tumor were subtracted from total tumor volume. Follow-up time ranged from 2 to 12 years. Results Five-year actuarial survival rates for patients with germinoma were 71%, 100% for patients with a teratoma component, and 100% for patients without histologic verification. Patients with germinomas or tumors suspected of being germinomas who were given more than 50 Gy had no local relapse. There was no correlation between primary local control by radiation therapy alone and initial tumor volume. The rate of tumor volume response to irradiation assesed by CT was significantly different in those patients who relapsed compared to those who did not relapse Conclusion Tumor response during radiation therapy using CT was considered to be predictive of primary local control with radiation therapy alone.  相似文献   
4.
Central nervous system germ cell tumors are rare lesions that are more frequently seen in the pediatric age group. Intracranial germinomas are a type of these germ cell tumors and commonly arise in the pineal region, suprasellar region, or less frequently at both areas (bifocal). Common features of this tumor depend on the location of the lesion(s) and include Parinaud''s syndrome, obstructive hydrocephalus, diabetes insipidus, panhypopituitarism, strabismus, and visual acuity defects. We report a case of bifocal pineal and suprasellar germinoma with posterior fossa metastases in a 15-year-old male patient. The involvement of the third ventricular floor and nonthickened inferior pituitary stalk of the suprasellar lesion suggest that it is a metastasis of a primary pineal lesion rather than a dual-primary. This distinction, with the presence of posterior fossa metastases, favors the use of more aggressive treatment with combination radiation therapy and chemotherapy for a better outcome.  相似文献   
5.
Tumors of the pineal region are a rare clinical entity, comprising approximately 3%-8% of pediatric tumors. Based on their histopathological features, they are typically classified as pineal parenchymal tumors and germ cell tumors, with the latter being more prevalent. Clinical presentation is heterogeneous, with symptoms arising either due to tumor invasion or compression of adjacent neurovascular structures and increased intracranial pressure. Imaging studies are paramount in evaluating pineal region lesions and establishing an accurate diagnosis, with MRI representing the gold standard. Herein, we present the case of a 16-year-old boy presented with recurrent headaches. A head MRI revealed a pineal gland lesion. Histopathological examination confirmed the diagnosis, and the patient underwent a successful gross total resection (GTR) of the tumor. This case report seeks to draw attention to the elusive clinical presentation and management of this infrequently encountered tumor, as well as emphasize the importance of considering pineal gland tumors in the differential diagnosis of recurrent, chronic headaches in pediatric patients.  相似文献   
6.
Primary intracranial germ cell tumors are rare, often affecting children and young patients. Germinomas are the most common type of germ cell tumors. We present the case of a 10-year-old child, who was admitted with decreased visual acuity, asthenia, polyuro-polydipsic syndrome, and gait disorder. His biological assessment showed an hypocortisolemia and diabetes insipidus. Imaging found a bifocal process in the suprasellar and pineal region, suggestive of a bifocal germinoma. Imaging data and the positivity of human chorionic gonadotrophin in the cerebrospinal fluid were in favor of the diagnosis of bifocal germinal tumor confirmed by biopsy. Currently the patient is hospitalized in pediatric oncology department.The diagnosis of germ cell tumors is based on imaging, tumor marker assays, and biopsy. They are treated by radiation therapy alone or in combination with reduction chemotherapy, and surgery for tumor residues. The location of the tumor usually makes surgery difficult.  相似文献   
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颅内原发生殖细胞瘤的放射治疗研究   总被引:3,自引:0,他引:3  
目的 报告57例原发颅内生殖细胞瘤无期治疗效果和生存质量,探讨最佳治疗方法。方法 30例行手术后放射治疗;27例行单纯放射治疗。53例全脑预防照射,其中51例肿瘤区追加足剂量;4例仅做肿瘤局部放射而未给任何中枢神经区预防。全脊髓预防放射34例而未做脊髓预防23例。4例放疗后1-4年因出现中枢神经再肿瘤灶接受了再程放疗。结果全部病人5、10、15、19年生存率是89.1%、87.0%、80.0%、66.7%,手术+放疗30例与单纯放疗27例之间生存率对比无差异(P>0.05)。病人临床症状缓解率95%。卡氏评分法对比疗前后生存质量均数差(P<0.001)。再程放疗4例生存时间超过2、7、10、17年。疗后远期,15岁以下14例(11例原发肿瘤位蝶鞍区)生殖器官发育能力受到明显影响,其因与幼年垂体受一定剂量照射直接有关(P<0.01)。结论 颅内原发生殖细胞争取手术的目的在于肿瘤减体以及获得病理诊断和分流服积水。放射治疗是达到治愈目的的有效方法。全脑预防放射应作为常规措施,脑预防剂量:26Gy-30Gy;肿瘤治疗量:50Gy左右。脊髓预防照射不可作为常规。提议对15岁以下患者行全脑预防照射时要保护垂体避免照射和不做脊髓预防照射,对原发蝶鞍区的肿瘤放射总剂量减少到45Gy-40Gy。对于疗后再发肿瘤灶给予合理再程放疗仍有较好效果。  相似文献   
10.
PURPOSE: We investigate the results of a surveillance program for stage I nonseminomatous germ cell tumors to validate a surveillance policy, and furthermore improve it by analyzing diagnostic instruments and identifying prognostic factors for relapse. MATERIALS AND METHODS: From 1982 to 1994, 90 patients with stage I nonseminomatous germ cell tumors entered a surveillance protocol after orchiectomy. Patients with relapse were treated with cisplatin based chemotherapy. A statistical analysis of possible prognostic factors for relapse was performed. RESULTS: Relapse occurred in 23 (26%) patients. Disease specific survival was 98.9%, and 1 patient died of tumor. Most relapses were located in retroperitoneal lymph nodes only (78%). Tumor markers were the most important indicators of relapse. However, in 22% of patients with relapse abdominal x-ray of lymphangiographic contrast showed the first sign of relapse. Computerized tomography located all but 1 relapse. Vascular invasion (p = 0.0001), tumor size (p = 0.0341) and presence of immature teratoma (p = 0.0154) were significantly predictive of relapse with the multivariate analysis, percentage embryonal carcinoma only by univariate analysis (p = 0.032). The relapse rate was highest (52%) when vascular invasion was present. CONCLUSIONS: With surveillance for stage I nonseminomatous germ cell tumors, excellent treatment results can be achieved that are comparable to primary retroperitoneal lymph node dissection. Tumor markers and computerized tomography are highly reliable for detecting relapse. Lymphangiography is still of staging value. Pathological factors may influence the choice of adjuvant treatment. However, relapse risks of 50% to 60% are maximally achieved with presently available prognostic factors, and so sparing morbidity of adjuvant treatment by a surveillance protocol remains a feasible option even in these patients.  相似文献   
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