代谢酶在嗜铬细胞瘤/副神经节瘤发病机制中的研究进展

嗜铬细胞瘤/副神经节瘤(PPGL)为临床上少见的儿茶酚胺内分泌肿瘤,大多数为良性,有10%~25%为恶性并转移。三羧酸循环为能量供应的途径之一,当循环中任何酶突变会引起代谢改变,促进细胞增殖与存活,与肿瘤的发生发展、侵袭和转移相关。代谢酶相关突变参与PPGL发病机制,可成为PPGL靶向治疗的方向。     

Management of Facial Nerve in Surgical Treatment of Previously Untreated Fisch Class C Tympanojugular Paragangliomas: Long-Term Results

The aim of this study was to evaluate the long-term facial nerve outcome according to management of the facial nerve in patients undergoing surgery for Fisch class C tympanojugular paragangliomas. The study population consisted of 122 patients. The infratemporal type A approach was the most common surgical procedure. The facial nerve was left in place in 2 (1.6%) of the 122 patients, anteriorly rerouted in 97 (79.5%), anteriorly rerouted with segmental resection of the epineurium in 7 (5.7%), and sacrificed and reconstructed in 15 (12.3%). One patient underwent cross-face nerve grafting. At last follow-up, House-Brackmann grade I to II was achieved in 51.5% of patients who underwent anterior rerouting and in 28.5% of those who underwent anterior rerouting with resection of the epineurium. A House-Brackmann grade III was achieved in 73.3% of patients who underwent cable nerve graft interposition. The two patients in whom the facial nerve was left in place experienced grade I and grade III, respectively. The patient who underwent cross-face nerve grafting had grade III. Gross total resection was achieved in 105 cases (86%). Management of the facial nerve in tympanojugular paraganglioma surgery can be expected to ensure satisfactory facial function long-term outcome.     

The value of magnetic resonance imaging in the differential diagnosis of parapharyngeal space tumours

Between 1987 and 1993 14 patients with a parapharyngeal space tumour were imaged by magnetic resonance imaging (MRI). The vagal body tumours, presenting in the poststyloid compartment, all showed flow voids with anterior and medial displacement of the internal carotid artery. None of the salivary gland tumours, all presenting in the prestyloid compartment with posterior displacement of the internal carotid artery, showed flow voids. MRI is superior compared with other modalities in evaluating the differential diagnosis, especially regarding vascular vs non-vascular tumours. It should encompass T₁ SE images to assess the presence or absence of flow voids. In vascular tumours angiography must be used to assess feeding vessels, multiplicity, and sides involved. T₁ GE images are useful as they allow superior identification of the internal carotid artery and its relation with the tumour accordingly. In addition to T₁ SE images, T₂ SE images may help in the evaluation of the differential diagnosis. In all non-vascular tumours aspiration cytology is required to differentiate between benign and malignant disease.     

Novel mutation in the TMEM127 gene associated with phaeochromocytoma

Phaeochromocytomas and paragangliomas are rare neuroendocrine tumours that arise from the adrenal glands or paraganglia (paragangliomas) within the abdomen, thorax and neck. Although it was originally suggested that approximately 10% of these tumours were inherited, it is now recognised that up to approximately 30% of these tumours are associated with a germline mutation in one of the phaeochromocytoma/paraganglioma susceptibility genes. Of the 12 currently known genes predisposing to these tumours, the TMEM127 gene is one of the more recently identified and appears to be present in approximately 2% of apparently sporadic phaeochromocytomas. We report a 33‐year‐old man who presented with an apparently sporadic adrenal phaeochromocytoma and was identified as carrying a novel TMEM127 germline mutation, p.Gln139X. Patients harbouring a germline TMEM127 mutation most commonly present with an apparently sporadic solitary adrenal phaeochromocytoma. Testing patients who present with a phaeochromocytoma or paraganglioma for an underlying germline mutation needs to be considered in all patients due to implications for family members, but a strategy based on clinical and immunohistochemical findings would be prudent to limit costs.     

Four cases of distinctive meningiomas with Zellballen growth pattern

Dong Y, Zhou X, Wu B, Wang J, Ma H, Zhou H, Jiang S, Lu G, Hu Q. Four cases of distinctive meningiomas with Zellballen growth pattern. APMIS 2009; 117: 936–40. Meningiomas are attributed to those tumours with slow‐growing pattern occurring predominantly in middle‐aged or elderly patients. Fifteen histological variants have been described based on the variable histomorphological features. Herein we report four cases with specific Zellballen growth pattern, giving the tumours a ‘paraganglioma‐like’ general aspect. The diagnosis of meningiomas was confirmed by immunohistochemical and ultrastructural findings. Histopathologists should be aware of this specific morphology which can lead to misdiagnosis.     

Giant Mitochondria with Paracrystalline Inclusions in Paraganglioma of the Urinary Bladder: Correlation with Mitochondrial Abnormalities in Paragangliomas of Other Sites

Mitochondrial abnormalities have received relatively little attention in the ultrastructural evaluation of paragangliomas. Review of the few literature references dealing with this issue, however, reveals that quantitative and qualitative changes of these organelles occur in that context. A bladder paraganglioma is described that was characterized by numerous mitochondria, which in addition displayed giant forms along with matrical paracrystalline inclusions. Upon retrospective review of 12 archival cases of paragangliomas, enlarged and structurally abnormal mitochondria were found in all of them. Although various speculations can be made, the mechanism of formation and the pathophysiologic significance of these abnormal mitochondria remain unknown. From a morphologic diagnostic point of view, however, these abnormalities, which in this case of bladder paraganglioma were also light microscopically evident, can be of significant help in establishing the correct diagnosis.     

嗜铬细胞瘤/副神节瘤的围手术期处理

嗜铬细胞瘤/副神节瘤是由神经嵴起源的嗜铬细胞产生的肿瘤,具有分泌儿茶酚胺的功能,而儿茶酚胺作用于血管、心脏,常常引起血液循环系统及代谢的改变。嗜铬细胞瘤手术前后血液中儿茶酚胺浓度的变化会引起相应血液动力学的改变,若没有充分的术前准备和术后监护,心血管意外事件的发生几率很高。因此,了解嗜铬细胞瘤/副神节瘤的病理学特点,术前进行良好的药物准备,术中轻柔的手术操作及与麻醉师的良好配合,术后ICU的严密监护,是嗜铬细胞瘤围手术期处理的关键,也是嗜铬细胞瘤/副神节瘤成功治疗的基本保障。     

Radiotherapy for glomus jugulare paraganglioma

Surgery has been long considered to be the treatment of choice for glomus jugulare paragangliomas, as it is the only modality able to totally eradicate the tumour. However, despite considerable progress in interventional radiology and nerve monitoring, surgery is associated with an unacceptably high complication rate for a benign tumour, explaining the growing place of radiotherapy in the management of these tumours. This review of the literature confirms the efficacy of conformal radiotherapy with or without intensity modulation and stereotactic radiotherapy, which both achieve tumour control rates ranging from 90% to almost 100% of cases, but for different tumour volumes, almost constant stabilization or even improvement of symptoms, and a considerably lower rate of adverse effects than with surgery. However, radiotherapy remains contraindicated in the presence of intracranial invasion or extensive osteomyelitis. In the light of these results, together with the improved quality of life and a better knowledge of the natural history of this disease, many authors propose radiotherapy as first-line treatment for all glomus jugulare paragangliomas regardless of their size, particularly in patients with no preoperative deficits.