Diagnostic imaging and surgical treatment of dumbbell tumors of the mediastinum

Benign Intrapulmonary Schwannoma With High Uptake on Fluorodeoxyglucose-18 (FDG-18 PET) Presenting as a Pancoast Tumor

A 46-year-old female patient was diagnosed with a rare and benign intrapulmonary schwannoma, a neurogenic tumor that represents approximately 20% of adult mediastinal tumors, with schwannomas being the most common subtype. The patient was initially asymptomatic; however, after a period of four years, the patient presented with bilateral extremity edema, chronic venous stasis, elevated right ventricular systolic pressure, and a slightly enlarged inferior vena cava. These symptoms were caused by the lung tumor compressing intrathoracic structures. This case highlights the need for early evaluation and proper management of neurogenic tumors to avoid serious symptoms and complications. It also emphasizes the importance of vigilant monitoring and prompt surgery to achieve the best outcome for patients with neurogenic tumors.

Video-assisted and minimally-invasive open chest surgery for the treatment of mediastinal tumors and masses

This article reviews the anatomy of the mediastinum as well as indications, limitations, techniques, and results of video-assisted thoracic surgery (VATS) and other minimally-invasive open-chest surgery approaches currently used for the surgical management of mediastinal tumors and masses. It is written by two surgeons with vastly different backgrounds and thoracic surgical experience. One of them is young and very familiar with VATS approaches and technologies while the other is a senior surgeon relatively unfamiliar with minimally-invasive techniques. This combination of authorship is ideal to analyze the pros and cons of the use of minimally-invasive approaches for the surgical management of mediastinal lesions such as thymic epithelial tumors (TETs) or neurogenic tumors. This is important because several thoracic surgeons have expressed concerns about the ability of thoracoscopic procedures to maintain adherence to sound oncological principles.

Spinal dumbbell lipoblastoma: a case-based update

INTRODUCTION

Lipoblastomas are benign tumors that arise from the proliferation of fetal adipose tissue. They are frequently found in the extremities, in the head, and in the neck. Dumbbell conformation (which refers to epidural tumors with extraspinal extension) has been described in only seven lipoblastoma cases so far.

CASE REPORT

We describe an 11-month-old patient with a large mediastinal dumbbell lipoblastoma. The mass was excised, but it recurred 1 year later when the MRI showed also multiple pleural lipoblastomatous lesions, thus establishing the diagnosis of lipoblastomatosis. The tumor has been removed with a second surgical procedure.

CONCLUSION

Radical excision of lipoblastomas is the gold standard but is not always possible to achieve. Residual lesions can be managed conservatively, on the basis of the benign nature of the tumor and of its potential maturation to normal fat. Recurrence of lipoblastoma appears in 15 % of non-radical excisions but has not yet been described in the form of lipoblastomatosis. A second surgery is indicated if the tumor mass reaches large dimensions, if it increases in size, and if it threatens the functionality of vital organs such as the spinal cord.

Surgery of benign neurogenic tumors in adults: single institution experience

The objective of this work is to review retrospectively our experience with 17 patients presenting with benign neurogenic tumors, managed in the department of thoracic surgery, Mohamed V Military Academic Hospital, Rabat, Morocco. Between 2003 and 2011, seventeen patients were surgically treated for benign neurogenic tumors of the mediastinum, among 112 mediastinal tumors operated during the same period. The mean age of the 17 patients was 46 years, including 11 females and 6 males. The information about clinical presentation, diagnostic procedures, surgical techniques and postoperative follow-up were extracted and analyzed from medical records. Symptoms related to the tumor were found in 13 patients (76,4%). The posterior mediastinum was the principal location (16 cases: 94%). Intraspinal extension was shown through MRI in one case. Surgical extirpation was complete in all patients. There were no tumor-related deaths and no significant complications. There were 13 schwannomas, 2 neurofibromas and 2 ganglioneuromas. Neurogenic tumors of the mediastinum in adults are mostly benign. Their only treatment is surgical extirpation. Video-assisted thoracoscopic resection is currently the best approach in selected patients.

A comparative study of video-assisted thoracoscopic resection versus thoracotomy for neurogenic tumours arising at the thoracic apex

OBJECTIVES

The surgical outcome of neurogenic tumours arising at the thoracic apex remains largely undefined. In this retrospective study, we compared the efficacy and safety of thoracoscopic surgery and thoracotomy for neurogenic tumours at the thoracic apex in 63 patients who received surgical treatment between 1992 and 2012 at our medical centre.

METHODS

Forty-four (69.8%) patients received thoracotomy (Group A) and 19 (30.2%) patients underwent video-assisted thoracoscopic surgery (Group B). Operative time, estimated blood loss (EBL), postoperative length of hospital stay and nervous system complications were recorded.

RESULTS

The two groups of patients were comparable in demographic and baseline characteristics except that Group A patients had a significantly larger tumour size (mean, 4.9 ± 1.0 cm) than Group B patients (mean, 4.1 ± 1.2 cm; P = 0.01). The mean operative time was markedly greater for Group A (120.2 ± 41.2 min) than Group B (93.2 ± 34.5 min; P = 0.009). Group A had significantly greater EBL (245.23 ± 197.78 ml) than Group B (117.4 ± 138.2 ml; P < 0.001). Total tumour resection was achieved in all patients and all neurogenic tumours were benign. The mean length of postoperative hospital stay was markedly longer in Group A (7.0 ± 2.1 days) than Group B (4.8 ± 2.0; P < 0.001). Postoperatively, brachial plexus injury was found in 1 patient (2.3%) in Group A and 4 patients (21.1%) in Group B (P = 0.026).

CONCLUSIONS

Though thoracoscopic surgery is associated with diminished blood loss, reduced operative time and shortened hospital stay, it has a markedly increased incidence of brachial plexus injury.

The transparaspinal approach: A novel technique for one-step removal of dumb-bell-shaped spinal tumors

Complex dumb-bell spinal tumors are challenging surgical lesions. Combined antero-posterior exposures have traditionally been used in their management. This combined exposure has the disadvantage of a two-stage operation with transthoracic or retroperitoneal dissection. With better understanding of biomechanics of spine and evolution of microsurgical technique, there has been resurgence of single stage surgeries, among which the transparaspinal exposure provides the simplest and the most direct route for resection of dumb-bell tumors. A 16-year-old male was admitted with history of back pain with radiation to left lower limb for 6 months, progressive weakness of both lower limbs for two months, and hesitancy of micturition for 1 month. A clinical diagnosis of cauda-conus lesion was made. Radiological investigations revealed a complex dumb-bell spinal tumor extending from lower part of L2-L4 vertebra, with large paraspinal extension through left L3 intervertebral foramina. Tumor was successfully removed in one step using a transparaspinal approach. We discuss technical details of this novel approach along with limitations and possible complications.

Extended lateral parascapular approach for resection of a giant multi-compartment thoracic schwannoma

BACKGROUND

Resection of giant thoracic schwannomas is challenging and usually requires a staged approach. The resection of the intraspinal component, usually via laminectomy, is done in one sitting and the intrathoracic component, via thoracotomy, follows at another. We describe the complete resection of a massive multi-compartmental thoracic schwannoma by an extended lateral parascapular approach.

METHOD AND FINDINGS

The tumor, which presented with local pain and scapular displacement, had intrathoracic paraspinal (10 x 5 x 4 cm), posterolateral upper thoracic paramuscular (19 x 7 x 4 cm), foraminal, and epidural components. It was removed at a single sitting, via a posterior extended lateral parascapular approach that did not require staged procedures, multiple incisions, or repositioning of the patient. This operation included resection of the thoracic, foraminal, and intraspinal components and posterior stabilization with pedicle screws and rods. There were no postoperative neurological complications.

CONCLUSIONS

The extended lateral parascapular approach allows complete resection of giant multi-compartment schwannomas of the thoracic spine that extend from the canal into the thoracic cavity. It also permits posterior stabilization through the same incision used for tumor removal.

Unusual dumbbell tumours of the mediastinum and thoracic spine

Due to a lack of large clinical series in the literature of chondrosarcomas and hydatid disease presenting as mediastinal dumbbell tumours, clinicians have limited experience on this topic. We present three unusual cases of dumbbell tumour involving the spinal canal; two patients had chondrosarcoma originating from Th8-Th9 and Th10-Th12; one patient had a hydatid cyst at Th5-Th6. We performed a single-stage combined thoracic-neurosurgical approach in two patients, and a double-staged approach in one patient. During the intraspinal dissection, an operating microscope was used under electrophysiological monitoring. Spinal canal reconstruction was not required for any of the cases. Preoperative knowledge of neuroforaminal extension and the relations between the tumour and adjacent neural-vascular structures is essential to prevent spinal cord damage and plan the surgical approach. In chondrosarcomas, prognosis depends on patient age, histological grade, extent of surgery and response to radiotherapy and/or chemotherapy. In this article, the diagnostic and surgical difficulties of these unusual tumours and current treatment modalities are discussed with a review of the relevant literature.

Posterior Intrathoracic Neurinoma Cure: A Transforaminal Resection After a Thoracotomy

Posterior intrathoracic neurogenic tumors often have an intraforaminal extension. Ten percent have an extension intraspinal and are called "dumbbell tumors." The surgically recommended techniques used to treat these conditions may have been applied too systematically, mainly when the diameter of the foramen was obviously enlarged and the possibility of removing the tumor existed. We report two cases to stress the importance of assessing the size of the intervertebral foramina in planning neurinoma cure.

The surgical approach to “dumbbell tumors” of the mediastinum

BACKGROUND

Successful management of posterior mediastinal dumbbell tumors depends on complete resection with adequate exposure. Correct preoperative assessment of neuroforaminal extension is important to avoid spinal cord injury. The surgical approach remains controversial.

METHODS

We report a retrospective analysis of posterior mediastinal dumbbell tumors over a 28-year period. All patients underwent one or more radiographic examinations available at the time of presentation and underwent a single-stage one-incision combined thoracic and neurosurgical procedure.

RESULTS

Among 16 patients aged 5 to 76 years, neuroforaminal involvement was identified before operation in 14 (87.5%) and during the procedure in 2 patients (12.5%). Computed tomography scan missed neuroforaminal involvement in 3 patients. Magnetic resonance imaging in 9 patients correctly identified neuroforaminal extension of the tumor but before MRI, myelography missed this extension in 3 patients. All patients underwent thoracotomy and posterior laminectomy was required in 10 of them. In 6 patients (38%) without laminectomy, resection required widening of the neural foramen in 3 whereas tumor was removed in 3 others through an already widened foramen. Spinal stabilization was required in 2 patients. There were 14 benign and 2 malignant lesions. Complete resection was performed in all patients without spinal cord injury or other major complication. No recurrences have been observed in a follow-up period from 2 months to 28 years (mean, 7.5 years).

CONCLUSIONS

Posterior mediastinal tumors should be evaluated for neuroforaminal involvement. A single-stage combined thoracic and neurosurgical approach is safe and leads to good long-term results. Laminectomy may be avoided in some patients.

Horner's syndrome caused by a thoracic dumbbell-shaped schwannoma: sympathetic chain reconstruction after a one-stage removal of the tumor

STUDY DESIGN

A case of Horner's syndrome caused by a thoracic dumbbell-shaped schwannoma is reported.

OBJECTIVES

To report a rare case of a mediastinal dumbbell-shaped schwannoma as a cause of Horner's syndrome and to show the result of intercostal nerve grafting for sympathetic chain reconstruction after resection of the sympathetic nerve.

SUMMARY OF BACKGROUND DATA

It has been reported that approximately 10% of neurogenic mediastinal tumors extend through the neural foramen into the spinal canal, creating a dumbbell shape. Although the most frequent causes of Horner's syndrome are tumors, a dumbbell-shaped schwannoma has rarely been described as a cause of the syndrome. Moreover, there have been no previous reports that primary sympathetic chain reconstruction has been performed with an intercostal nerve graft after resection of the sympathetic nerve with the tumor.

METHODS

A 48-year-old woman was diagnosed with a mediastinal tumor by routine chest radiography. The patient had right-sided Horner's syndrome, the signs of which she had not noticed. Surgical resection of the dumbbell-shaped tumor was performed in a one-stage combined resection of both the intraspinal and the mediastinal component of the tumor. Primary sympathetic chain reconstruction was also performed with an intercostal nerve graft.

RESULTS

The tumor was resected completely, and no recurrence of the tumor was observed 1 year after the operation. Blepharoptosis and anhidrosis on the right side of her face and upper limb gradually improved after surgery, and compensatory oversweating on the left side eventually improved. In bright illumination, the right pupil diameter was 3.5 mm and the left was 5 mm after surgery; the right pupil measured 4 mm and the left measured 5 mm 1 year after the operation.

CONCLUSIONS

A mediastinal dumbbell-shaped schwannoma has rarely been described as a cause of Horner's syndrome. Primary sympathetic nerve reconstruction with an intercostal nerve was shown to be useful after resection of the sympathetic nerve involved in the tumor.

Thoracoscopy: the preferred approach for the resection of selected posterior mediastinal tumors

The posterior mediastinum is a common site for neurogenic tumors. These are mostly asymptomatic and detected incidentally during radiologic investigations. However, they occasionally present with compressive or neurologic symptoms. The tumors are mostly benign but can also be malignant. Left untreated, they continue to grow. Therefore, once detected, resection is always advised. Traditionally, resection has been performed by standard posterolateral thoracotomy. More recently, such tumors have been removed thoracoscopically. We report our experience with three such cases and present a comprehensive analysis of cases of thoracoscopic resection of posterior mediastinal neurogenic tumors reported in the English literature to suggest guidelines for their current management.

An unusual posterior mediastinal lipoblastoma with spinal epidural extension presenting as a painful suprascapular swelling: case report and a brief review of the literature

Lipoblastoma is a rare benign pediatric neoplasm of fetal-embryonal fat with little risk of recurrence following total microsurgical excision, but it may progress to local invasion or infiltration if not treated surgically. No adjuvant therapies are usually necessary once the tumor is excised. It is best diagnosed on histopathological studies following excision. An unusual posterior mediastinal lipoblastoma in a 2-year-old Omani girl with spinal epidural extension clinically manifested as a progressive painful suprascapular swelling is reported. It was initially construed to be a benign lipoma, but progressively increasing pain and mild imbalance whilst walking with a tendency to fall on the right side prompted neurosurgical referral and eventual total excision without any added morbidity. Interesting clinical and neuroimaging (CT & MRI) findings are presented and discussed, with a brief review of the literature.

Thoracoscopic removal of intrathoracic neurogenic tumors: a combined Chinese experience

OBJECTIVE

To review the surgical and clinical results of minimally invasive resection of intrathoracic neurogenic tumors using a video-assisted thoracoscopic technique.

SUMMARY BACKGROUND DATA

Thoracoscopy has emerged as a possible means for diagnosing and managing various intrathoracic disorders. Benign intrathoracic tumors often are ideal lesions for resection using a video-assisted technique. The authors report on their combined experience with the thoracoscopic resection of 143 intrathoracic neurogenic tumors.

METHODS

Between March 1992 and February 1999, 143 patients with intrathoracic neurogenic tumors were diagnosed and underwent resection using video-assisted thoracoscopic techniques in three teaching centers. Case selection, surgical technique, and clinical results were reviewed.

RESULTS

The average age of the patients was 40.8 years; 57.3% were male. Thirty-eight patients (27%) had symptoms attributable to the masses. Seventy-two masses were neurofibromas, 33 were neurilemmomas, 7 were paragangliomas, and 31 were ganglioneuromas. All but seven tumors were located in the posterior mediastinum. The masses were on average 3.5 cm in greatest diameter. The mean surgical time was 40 minutes, and the average hospital stay was 4.1 days. There were no major postoperative complications or recurrences to date. Nine patients reported paresthesias over the chest wall during a mean follow-up of 29 months.

CONCLUSIONS

Resection of intrathoracic neurogenic tumors using a thoracoscopic technique based on standard surgical indications would seem to be appropriate. Most of these masses are benign and readily removed. For dumbbell tumors, a combined thoracic and neurosurgical approach is mandatory.

Embryology and surgical anatomy of the mediastinum with clinical implications

This article discusses general mediastinal embryology, and provides anatomy and algorithms for the investigation of mediastinal masses. The superior, anterior, middle, and posterior mediastina also are detailed.

Thoracoscopic excision of a posterior mediastinal "dumbbell" tumor using a combined approach

Up to 10% of neurogenic tumors in the posterior mediastinum demonstrate intraspinal extension. Historically, these lesions have been considered resectable only by a combined thoracic and neurosurgical approach using thoracotomy. Herein, a thoracoscopic excision of a "dumbbell" lesion within the framework of a combined approach is described.

Combined microneurosurgical and thoracoscopic removal of neurogenic dumbbell tumors

The resection of posterior mediastinal dumbbell tumors has until now required laminectomy and some form of open access to the thoracic cavity. Over a 1-year period, a novel surgical approach combining posterior microneurosurgical and anterior video-assisted thoracoscopy techniques was used in 4 patients. In 3 patients, the tumor was removed successfully with minimal postoperative discomfort and rapid recovery. In the fourth patient, limited thoracotomy became necessary to control bleeding. This new approach, which combines modern-day neurosurgical and general thoracic surgical techniques, appears safe and could become the preferred method for removing most benign posterior mediastinal dumbbell tumors.

Primary mediastinal neoplasms (other than thymoma)

Primary mediastinal neoplasms encompass a long list of histologically diverse lesions that can arise from a wide variety of mediastinal structures. Recent advances in diagnostic techniques have considerably enhanced the evaluation of the mediastinum with use of noninvasive or minimally invasive procedures. In adults, most primary mediastinal neoplasms can be classified in one of four categories: thymus-derived neoplasms, neurogenic tumors, lymphomas, or germ cell neoplasms. In children, neurogenic tumors (especially neuroblastomas) and lymphomas are most frequently encountered. Because of the presence of many vital structures in the confined thoracic cavity, even benign mediastinal neoplasms can cause severe symptoms from the mass effect and therefore warrant a carefully planned management strategy. With modern therapeutic and surgical interventions, associated morbidity and mortality can often be substantially decreased.