Composite ganglioneuroma-paraganglioma of the filum terminale

Minimally Invasive Resection of a Gangliocytic Paraganglioma of the Cauda Equina: A Case Report and Review of Literature

Gangliocytic paraganglioma (GP) is considered a rare neuroendocrine tumor (NET) most often located in the distal half of the duodenum. Insufficient reports describe tumors of this histological type located in the distal parts of the spinal canal, the conus medullaris and cauda equina. To date, nine cases of GP of the cauda equina and one case of GP of conus medullaris have been described. After analyzing all available treatment reports of GP, a study described it as a tumor with an extremely good prognosis in cases of total tumor removal. Here, we present a case of a female patient with a GP at the level of the L4 vertebra treated at Burdenko Neurosurgical Center using a minimally invasive approach through a tubular retractor. The tumor was removed en bloc through an intralaminar opening, and the patient was discharged two days after surgery with total regression of symptoms.

Primary Paraganglioma of the Spine: A Systematic Review of Clinical Features and Surgical Management in Cauda Equina vs Non-Cauda Equina Lesions

BACKGROUND

Primary spine paragangliomas are rare tumors. Surgical resection plays a role, but aggressive lesions are challenging. We reviewed the literature on primary spine paragangliomas.

METHODS

PubMed, Scopus, Web of Science, and Cochrane were searched upon the PRISMA guidelines to include studies on primary spine paragangliomas. Clinical-radiological features, treatments, and outcomes were analyzed and compared between cauda-equina vs non-cauda-equina tumors.

RESULTS

We included 143 studies comprising 334 patients. Median age was 46 years (range, 6-85). The most frequent symptoms were lower-back (64.1%) and radicular (53.9%) pain, and sympathetic in 18 patients (5.4%). Cauda-equina paragangliomas (84.1%) had frequently lumbar (49.1%) or lumbosacral (29%) locations. Non-cauda-equina tumors were mostly in the thoracic (11.4%), thoracolumbar (5.1%), and cervical (3.6%) spine. Median tumor diameter was 2.5cm (range, 0.5-13.0). Surgical resection (98.5%) was preferred over biopsy (1.5%). Decompressive laminectomy (53%) and spine fusion (6.9%) were also performed. Adjuvant radiotherapy was delivered in 39 patients (11.7%) with aggressive tumors. Post-treatment symptomatic improvement was described in 86.2% cases. Median follow-up was 19.5 months (range, 0.1-468.0), and 23 patients (3.9%) had tumor recurrences. No significant differences were found between cauda-equina vs non-cauda-equina tumors.

CONCLUSION

Surgical resection is effective and safe in treating primary spine paragangliomas; however, adjuvant treatments may be needed for aggressive lesions.

Composite pheochromocytoma/paraganglioma-ganglioneuroma: analysis of SDH and ATRX status, and identification of frequent HRAS and BRAF mutations

INTRODUCTION

Composite pheochromocytoma/paraganglioma (CP) is a rare neoplasm with most cases presented as single reports. Little is known about its pathogenesis and relationship with ordinary pheochromocytoma (PCC) or paraganglioma (PGL). Our study is aimed at analyzing the status of SDH and ATRX and identifying novel genetic changes in CP.

METHODS

Eighteen CP cases were collected. SDH and ATRX status was screened by immunohistochemistry. Targeted region sequencing (TRS) was successfully performed on formalin-fixed paraffin-embedded tissues in two cases within 3 years. Based on the TRS result, Sanger sequencing of BRAF and HRAS was performed in fifteen cases (including the two cases with TRS performed), with three cases excluded due to the limited amount of tissue.

RESULTS

Histopathologically, all the cases were composite PCC/PGL-ganglioneuroma (GN). The GN components were either closely admixed or juxtaposed with the PCC/PGL components, with a highly variable percentage (10-80%). All cases stained positive for SDHB and ATRX. HRAS and BRAF mutations were identified during TRS. In the subsequent Sanger sequencing, 20.0% (3/15) harbored BRAF mutations (K601E and K601N) and 46.7% (7/15) harbored HRAS mutations (Q61R, Q61L, G13R). The mutation rates were both significantly higher than reported in ordinary PCC/PGL.

CONCLUSIONS

We demonstrated that composite PCC/PGL-GN might be a unique entity with frequent HRAS and BRAF mutations rather than genetic changes of SDH and ATRX. Our findings revealed the possible pathogenesis of composite PCC/PGL-GN and provided clues for potential treatment targets.

Anatomical and Histological Analysis of a Complex Structure Too Long Considered a Simple Ligament: The Filum Terminale

BACKGROUND

The intradural filum terminale (iFT) connects the conus medullaris (CM) with the dural sac (DS), and the extradural filum terminale (eFT) connects the DS to the coccyx. The aim of the present study was to update the description of the FT and integrate these data in a physiological and pathological context.

METHODS

Anatomical measurements and histological investigations were performed on 10 human cadavers.

RESULTS

The mean length of the iFT and eFT was 167.13 and 87.59 mm, respectively. The mean cranial diameter of the iFT was 1.84 mm. It was >2 mm in 2 specimens. The mean half and caudal diameter of the iFT was 0.71 and 0.74 mm, respectively. The cranial diameter of the eFT correlated with the caudal diameter of the eFT (ρ = 0.94; P = 0.02). The level of the CM-iFT junction correlated significantly with the iFT length (ρ = -0.67; P = 0.03). The mobilization of the iFT was not transmitted to the extradural elements and vice versa. The iFT contained axons and ependymal cells, which were dense in the first third and then randomly arranged caudally in islets. This could explain why ependymomas can occur all along the iFT. Ganglion cells were abundant around the junction with the DS. The eFT contained smooth muscle cells, adipocytes, and axons. A mechanoreceptor was identified in 1 specimen.

CONCLUSIONS

Consistently with their common embryological origin, a real anatomical and histological continuum is present between the CM and FT. The FT should, therefore, no longer be considered a simple ligament but, rather, a complex fibrocellular structure.

Lumbar Ganglioneuroma from the Paravertebral Body Presenting in Continuity Between Intradural and Extradural Spaces

BACKGROUND

Ganglioneuroma is a well-differentiated benign tumor that develops from the ganglion cells of the posterior mediastinum, retroperitoneum, cervical spine, and adrenal glands. The paravertebral body, in which the sympathetic trunk exists, is a common tumor site, and tumor sometimes invades the spinal canal through the intervertebral foramen. There have been no reports regarding tumors with intradural and extradural continuity. We report a paravertebral ganglioneuroma extending between the intradural and extradural spaces and its surgical treatment.

CASE DESCRIPTION

A 33-year-old man was admitted to the hospital with progressive left lower limb numbness. A dumbbell-type tumor progressing to the spinal canal via the left intervertebral foramen from the paravertebral body at L1-2 was detected, and intradural calcified lesions were found. Pathologic examination of a computed tomography-guided biopsy sample revealed a ganglioglioma. The extradural tumor was removed; however, the left lower limb pain gradually worsened. As complete block was observed on myelography, the intradural tumor was removed 8 months later. Intraoperative findings revealed that the intradural and extradural tumors were continuous through the L1 nerve root.

CONCLUSIONS

This is the first known reported case of paravertebral ganglioneuroma presenting in continuity between the intradural and extradural spaces.

Gangliocytic Paraganglioma of Dorsolumbar Spine: A Rare Tumor at Rare Site

Spinal paragangliomas are rare benign tumors. The gangliocytic paragangliomas (GP) of spine are even rarer. The GPs are almost exclusively seen in duodenum. In spine, the usual site of affection is cauda equina region. The involvement of other spinal levels is far less often and includes thoracic and cervical region. We report this case of GP involving the conus medullaris region and reaching up to the upper part of cauda equina. The prognosis of spinal GP is excellent after total excision, as it is classified under WHO Grade I tumor. The patient made a full recovery after tumor removal. Clinical, radiological, and pathological characteristics of this rare tumor are discussed here along with.

Composite Paraganglioma: Pioneering in the Head and Neck

Composite paragangliomas are rare with less than 20 cases documented in the abdomen, retroperitoneum, and urinary bladder. In this article, we report the first case of composite paraganglioma in the head and neck presenting as a soft tissue mass in the neck adjacent to the carotid artery in a 50-year-old woman. We discuss the clinicopathologic findings and genetic implications, and we review the literature of this rare entity.

Update on Adrenal Tumours in 2017 World Health Organization (WHO) of Endocrine Tumours

The fourth edition of the World Health Organization (WHO) classification of endocrine tumours contains substantial new findings for the adrenal tumours. The tumours are presented in two chapters labelled as "Tumours of the adrenal cortex" and "Tumours of the adrenal medulla and extra-adrenal paraganglia." Tumours of the adrenal cortex are classified as cortical carcinoma, cortical adenoma, sex cord stromal tumours, adenomatoid tumour, mesenchymal and stromal tumours (myelolipoma and schwannoma), haematological tumours, and secondary tumours. Amongst them, schwannoma and haematological tumours are newly documented. The major updates in adrenal cortical lesions are noted in the genetics of the cortical carcinoma and cortical adenoma based on the data from The Cancer Genome Atlas (TCGA). Also, a system for differentiation of oncocytoma from oncocytic cortical carcinoma is adopted. Tumours of the adrenal medulla and extra-adrenal paraganglia comprise pheochromocytoma, paraganglioma (head and neck paraganglioma and sympathetic paraganglioma), neuroblastic tumours (neuroblastoma, nodular ganglioneuroblastoma, intermixed ganglioneuroblastoma, and ganglioneuroma), composite pheochromocytoma, and composite paraganglioma. In this group, neuroblastic tumours are newly included in the classification. The clinical features, histology, associated pathologies, genetics, and predictive factors of pheochromocytoma and paraganglioma are the main changes introduced in this chapter of WHO classification of endocrine tumours. The term "metastatic pheochromocytoma/paraganglioma" is used to replace "malignant pheochromocytoma/paraganglioma." Also, composite pheochromocytoma and composite paraganglioma are now documented in separate sections instead of one. Overall, the new classification incorporated new data on pathology, clinical behaviour, and genetics of the adrenal tumours that are important for current management of patients with these tumours.

Paragangliomas: update on differential diagnostic considerations, composite tumors, and recent genetic developments

Recent developments in molecular genetics have expanded the spectrum of disorders associated with pheochromocytomas (PCCs) and extra-adrenal paragangliomas (PGLs) and have increased the roles of pathologists in helping to guide patient care. At least 30% of these tumors are now known to be hereditary, and germline mutations of at least 10 genes are known to cause the tumors to develop. Genotype-phenotype correlations have been identified, including differences in tumor distribution, catecholamine production, and risk of metastasis, and types of tumors not previously associated with PCC/PGL are now considered in the spectrum of hereditary disease. Important new findings are that mutations of succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD, and SDHAF2 (collectively "SDHx") are responsible for a large percentage of hereditary PCC/PGL and that SDHB mutations are strongly correlated with extra-adrenal tumor location, metastasis, and poor prognosis. Further, gastrointestinal stromal tumors and renal tumors are now associated with SDHx mutations. A PCC or PGL caused by any of the hereditary susceptibility genes can present as a solitary, apparently sporadic, tumor, and substantial numbers of patients presenting with apparently sporadic tumors harbor occult germline mutations of susceptibility genes. Current roles of pathologists are differential diagnosis of primary tumors and metastases, identification of clues to occult hereditary disease, and triaging of patients for optimal genetic testing by immunohistochemical staining of tumor tissue for the loss of SDHB and SDHA protein. Diagnostic pitfalls are posed by morphological variants of PCC/PGL, unusual anatomic sites of occurrence, and coexisting neuroendocrine tumors of other types in some hereditary syndromes. These pitfalls can be avoided by judicious use of appropriate immunohistochemical stains. Aside from loss of staining for SDHB, criteria for predicting risk of metastasis are still controversial, and "malignancy" is diagnosed only after metastases have occurred. All PCCs/PGLs are considered to pose some risk of metastasis, and long-term follow-up is advised.

Composite paraganglioma and ganglioneuroma in the retroperitoneum: a case report

Reports of a composite paraganglioma (PG) and ganglioneuroma (GN) in the retroperitoneum are rare. In the present case, dynamic computed tomographic (CT) findings showed a 30 × 22 × 20 mm tumor that was located in the retroperitoneum and which was dissociated from pancreatic tissue and the left adrenal gland. The markedly reddish tumor showed a clear margin and central multicystic changes on the cut surface. The tumor was composed of two major components, the PG and the GN. The paraganglionic cells in the PG component, which were arranged in a nested pattern, occupied the main and central part of the tumor. Both ganglionic cells and Schwann cells in the GN were located in a unorganized pattern in the periphery. The paraganglionic cells exhibited a Zellballen pattern, which consisted of an association of edematous vascular-rich stroma and focal hemorrhage, resulting in multicystic changes. These centrally located tumor cells were pleomorphic in part and did not have mitotic figures. In the periphery, Schwann cells, which were arranged in an obscure and fascicular pattern that was intermingled with large ganglionic cells, were located adjacent to the PG component with a mostly sharp margin. With higher magnification, the border was not as sharp, as revealed especially with chromogranin-A immunostain, in which both the PG and GN components were focally intermingled with each other. The histogenesis of the composite PG and GN was thought to be extraadrenal neural crest cells in the retroperitoneum because the tumor was not located in the adrenal gland or the Zuckerkandl organ, according to the CT findings. The immunohistochemical findings of this rare case of a composite PG and GN in the retroperitoneum are reported with a focus on the peculiar arrangement of these two components.

PARAGANGLIOMA IN THE SPINE: CASE REPORT

Paragangliomas are rare neuroendocrine tumors that originate in specialized cells derived from neural crest cells, affecting the region of the carotid or jugular-tympanic artery. They are rare within the spinal canal and, when they occur, they are normally found in the extramedullary intradural compartment of the lumbosacral region. This report presents the case of a 26-year-old male patient who was diagnosed with pathological fracture of the thoracic spine (T10), secondary to paraganglioma, thus causing complete spinal cord injury. Surgical treatment was performed at the General Hospital of the State of Bahia and the complication of excessive bleeding occurred, which indicated that there had been a need for prior embolization. Because of this, the authors recommend caution when evaluating and treating this rare lesion that causes neurological deficits, with careful surgical planning in order to catastrophic complications.

Functional 'composite' pheochromocytoma-ganglioneuroma presenting as a pancreatic mass

Pheochromocytomas rarely have 'composite' forms in which they demonstrate histologic features of a typical paraganglioma in combination with those of a neural component. Extra-adrenal 'composite' pheochromocytomas are distinctly uncommon. We describe herein a unique case of a 34-year-old female patient with type 1 neurofibromatosis who presented with abdominal pain and paroxysmal hypertension. Imaging revealed a pancreatic mass with biliary and pancreatic ductal dilatation and a hormonal assay led to the diagnosis of functional pheochromocytoma. She underwent surgical resection and histopathology revealed a composite paraganglioma-ganglioneuroma. Clinical, biochemical and radiological aspects of this rare tumor and its association with neurofibromatosis and other hereditary cancer syndromes are discussed.