Decision Making in Retroperitoneal Nerve Sheath and Nerve-Associated Tumors: A Modular Approach.

BACKGROUND: Surgical treatment of retroperitoneal nerve and nerve-associated tumors is challenging, especially in cases with large extent. A single surgical access may have limitations and jeopardize patients. OBJECTIVE: To present a series of patients to illustrate our individually tailored treatment concept and decision pathway. METHODS: Retrospectively, clinical findings and imaging were related to surgical features and outcome. An algorithm for choice of approach was established. RESULTS: From 2012 to 2017, we operated on n = 13 patients with retroperitoneal tumors, of these n = 9 were included (n = 6 female, n = 3 male). Histological findings included n = 2 schwannomas, n = 2 malignant peripheral nerve sheath tumors, n = 1 non-origin sarcoma, n = 1 perineurioma, n = 1 intraneural ganglion cyst, n = 1 lymphoma, and n = 1 paraganglioma. In n = 6 patients, we used a monoportal (retroperitoneal/transperitoneal) approach; in n = 2 patients, a biportal retroperitoneal to inguinal/transperitoneal to dorsal approach; and in n = 1 patient, a triportal transperitoneal to dorsal to gluteal approach. In n = 2 patients, we performed an open biopsy only; in n = 2 patients, a tumor enucleation; in n = 3 patients, a subtotal function-sparing resection; in n = 1 patient, a complete resection; and in n = 1 patient, intraneural decompression. In n = 1 patient, a new motor deficit appeared. n = 4 patients required further radio-oncological treatment. n = 8/9 patients are alive without tumor progress or recurrence. CONCLUSION: Retroperitoneal nerve or nerve-associated tumors encompass multiple entities. Depending on suspected histology and tumor extension, extensile or combined surgical approaches may be necessary. We present our algorithm for assessment and decision-making regarding surgical access ports and pathways.

Surgical treatment of posterior mediastinal neurogenic tumors.

BACKGROUND: Posterior mediastinal neurogenic tumors are among the most frequent mediastinal masses in adults. These tumors may be dumbbell shaped, extending into the spinal canal, exclusively paraspinal or apical tumors extending in the cervical region. In this report, we present our experience in the surgical resection of these tumors and discuss the surgical strategies for such tumors. METHODS: A retrospective analysis was performed of 121 patients who underwent surgery for posterior mediastinal neurogenic tumors at our department during the period 2009 to 2016. Seventy-four tumors were excised via video-assisted thoracic surgery (VATS). Other approaches included thoracotomy, supraclavicular incision, supraclavicular incision plus thoracotomy/VATS, and a posterior approach with laminectomy combined with thoracotomy/VATS. RESULTS: Tumors were resected completely in 119 cases and partially in two. The majority of the tumors were benign nerve sheath tumors. No recurrence developed during postoperative median follow-up period of 31 months. CONCLUSION: Most posterior neurogenic tumors can be resected via VATS. Thoracotomy is the appropriate surgical approach for large tumors. A supraclavicular approach is recommended for tumors extending in the cervical region, and this can be combined with VATS or thoracotomy in case of larger masses. A posterior approach could be used for patients with dumbbell tumors.

Multinodular and vacuolating neuronal tumors in epilepsy: dysplasia or neoplasia?

Multinodular and vacuolating neuronal tumor (MVNT) is a new pattern of neuronal tumour included in the recently revised WHO 2016 classification of tumors of the CNS. There are 15 reports in the literature to date. They are typically associated with late onset epilepsy and a neoplastic vs. malformative biology has been questioned. We present a series of ten cases and compare their pathological and genetic features to better characterized epilepsy-associated malformations including focal cortical dysplasia type II (FCDII) and low-grade epilepsy-associated tumors (LEAT). Clinical and neuroradiology data were reviewed and a broad immunohistochemistry panel was applied to explore neuronal and glial differentiation, interneuronal populations, mTOR pathway activation and neurodegenerative changes. Next generation sequencing was performed for targeted multi-gene analysis to identify mutations common to epilepsy lesions including FCDII and LEAT. All of the surgical cases in this series presented with seizures, and were located in the temporal lobe. There was a lack of any progressive changes on serial pre-operative MRI and a mean age at surgery of 45 years. The vacuolated cells of the lesion expressed mature neuronal markers (neurofilament/SMI32, MAP2, synaptophysin). Prominent labelling of the lesional cells for developmentally regulated proteins (OTX1, TBR1, SOX2, MAP1b, CD34, GFAPδ) and oligodendroglial lineage markers (OLIG2, SMI94) was observed. No mutations were detected in the mTOR pathway genes, BRAF, FGFR1 or MYB. Clinical, pathological and genetic data could indicate that MVNT aligns more with a malformative lesion than a true neoplasm with origin from a progenitor neuro-glial cell type showing aberrant maturation.

Intrathoracic neurogenic tumor with malignant transition-20 years operation experience in a medical center of China.

OBJECTIVE: Malignant peripheral neurogenic tumor is always found in large peripheral nerve of the extremities, however, benign peripheral neurogenic tumors of chest is an uncommon disorder, furthermore, malignant transition is even rare. So far, few cases have been reported. We studied 45 neurogenic thoracic tumors patients with malignant transition. METHODS: We retrospectively reviewed clinical data of 45 malignant neurogenic thoracic tumors from 1992 to 2012, including 11 (24.44%) cases of borderline tumors (group X), 13 cases of (28.88%) low-grade malignant tumor (group L), and 21 cases (46.66%) of malignant tumors (group M). Specifically, we reviewed the clinical characteristics, surgical approach, postoperative outcome, complications and prognosis of these patients. RESULTS: All tumors are located in the thoracic cavity, and arising from sympathetic or spinal nerve or their branches from the lung or posterior mediastinum. The patients from groups X and L had more complete resection than group M. Unfortunately, one patient was dead intra operatively in Group M. Group M had more recurrence than groups X and L. Our results indicates that, the survival rate may be correlated with tumor size, malignant degree (P=0.018), tumor recurrence and incomplete resection (P<0.05). CONCLUSION: The most effective treatment method for these tumors is early identification and resection by minimally invasive surgery during benign stage. In addition, regarding low-grade malignant tumor, non-radical surgery could also be responsible for the low survival rate.

Intraoperative esophagoscopy provides accuracy and safety in video-assisted thoracoscopic enucleation of benign esophageal submucosal tumors.

Benign esophageal tumors are rare; complete surgical resection is essential for the management of the submucosal tumors. Larger, symptomatic, or non-diagnostic lesions should be resected for both diagnostic and therapeutic indications. Video-assisted thoracic surgery has become a popular treatment in the field of thoracic surgery; however, thoracoscopic esophageal surgery may lead to an increase in operative complications. The effect and safety of thoracoscopic surgery for esophageal submucosal lesions were evaluated. A retrospective study evaluated patients undergoing thoracoscopic treatment of benign submucosal tumors. Between March 2011 and December 2013, 17 patients underwent thoracoscopic resection of benign submucocal tumors. Intraoperative esophagoscopy was performed for tumor localization by transillumination and confirmation of mucosal integrity after enucleation in every patient. Median patient age was 47 years (range 30-65). The median surgery time was 170 minutes (range 80-429). The median tumor size was 3.8 cm (range 1.3-9). The median hospital stay was 4 days (range 2-12). There were 16 leiomyoma and 1 neurogenic tumor. There was one case of conversion to thoracotomy because of residual tumor after enucleation. Mucosal injuries occurred in three patients, two accidentally and one intentionally; each patient was treated with primary repair and confirmed integrity with flexible esophagoscopy at operating room. The small sized tumor with intraoperative esophagoscopy could be localized. Esophagoscopic assistance was necessary in eight patients to have better idea where to make myotomy. There were no major morbidities such as postoperative leakage or mortality. Esophageal submucosal tumors can be treated safely with thoracoscopic surgery. However, intraoperative esophagoscopy allows accurate tumor localization, direction of esophageal access incision, and decreases complications during VATS enucleation of esophageal submucosal tumors.

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.

Intrathoracic neurogenic tumors.

BACKGROUND: Intrathoracic neurogenic tumors are uncommon neoplasms arising from nerve tissues. This study reports on our 24-year single-center experience with intrathoracic neurogenic tumors. PATIENTS AND METHODS: We retrospectively analyzed the postoperative pathological records of 19,378 operations performed in our clinic between January 1988 and December 2011 and included cases with diagnosis of neurogenic tumors. RESULTS: The study included 149 patients (90 females and 59 males) with an average age of 24.5 years (7 months to 77 years). The study group comprised 29 infants and children, and 120 adults. Of the patients, 72 had benign schwannomas, 10 malignant schwannomas, 17 neurofibromas, 24 ganglioneuromas, 9 ganglioneuroblastomas, 4 neuroblastomas, 9 primitive neuroectodermal tumors, and 4 paragangliomas. Concerning the location of these lesions, 131 were located in the posterior mediastinum, 8 in the lung parenchyma, 5 in the chest wall, 3 in the anterior mediastinum, and 2 in the thoracic inlet. The majority of nerve cell tumors were in infants and children (79.3%), whereas the nerve sheath tumors most commonly occurred in adults (78.3%). There were 117 benign and 32 malignant tumors across all age groups. The rate of malignancy was 41.4% in infants and children, compared with 16.7% in adults. Symptoms were seen in 65% of the adult patients and 79.3% of the infant and children patients. Seven tumors were associated with von Recklinghausen's disease. In six patients (4.0%), the tumor showed an intraspinal extension. Surgical resection of the tumor was complete in 142 of 149 patients (95.3%). CONCLUSION: The treatment of choice for malignant and benign thoracic neurogenic tumors is complete resection. The objective of resection is to avoid local invasion, facilitate differential histopathological diagnosis to determine other treatment options, and to prevent malignant degeneration.

Preoperative symptoms and postoperative sequelae of intrathoracic neurogenic tumors: a single institution's experience.

OBJECTIVE: Most intrathoracic neurogenic tumors are resected for therapeutic diagnosis; many adult tumors are benign. However, few studies have reported the preoperative symptoms, postoperative modalities, and sequelae of these tumors. We focused on and evaluated the diversity and postoperative prognosis of these tumors. METHODS: We assessed 31 consecutive cases of intrathoracic neurogenic tumors resected at Tsuchiura Kyodo General Hospital between 1988 and 2012. Two cases involved multiple tumors; therefore, complete resection or enucleation was performed only in the remaining 29 cases. The patients' clinical records were investigated retrospectively. RESULTS: All tumors were benign. Five cases (16.1 %) presented with preoperative symptoms; 2 cases with non-neurologic symptoms (dysphagia due to tumor oppression and a massive hemothorax with neurofibromatosis type 1) improved after surgery, but 3 others with neurologic symptoms (back pain, hand motor paralysis, and Horner's syndrome) did not. Ten cases (32.3 %) presented with postoperative modalities or sequelae. Eight cases presented with neurologic sequelae (Horner's syndrome, 4 cases; grip weakness, 3 cases; hypohidrosis, 3 cases; and hand numbness, 2 cases). All the patients presenting with neurologic sequelae had tumors proximal to the first or second thoracic vertebra; no tumors proximal to or under the third thoracic vertebra caused neurologic sequelae. Severe neurologic sequelae in daily life were observed in 2 cases, but they did not radically improve. CONCLUSIONS: While the non-neurologic symptoms caused by intrathoracic neurogenic tumors can be resolved by resection, the neurologic symptoms may not improve. Tumors proximal to the first or second thoracic vertebra can cause postoperative neurologic sequelae.

Experience with wound complications after surgery for sacral tumors.

PURPOSE: The aim of this article is to summarize our experience in treating sacral wound complications after sacrectomy. We focus, in particular, on factors associated with wound complications, including surgical site infection (SSI) and wound dehiscence. METHODS: The definition of SSI devised by Horgan et al. was applied. Wound dehiscence was defined as a wound showing breakdown in the absence of clinical signs meeting the diagnostic standard for SSI. Between September 1997 and August 2009, 387 patients with a sacral tumor underwent sacrectomy performed by the same team of surgeons and were followed up for ≥ 12 months. Potential risk factors were evaluated for univariate associations with SSI and wound complications. Multivariable conditional logistic regression was used to identify the combined effects of several risk factors. RESULTS: Of the 387 wounds studied, 274 healed uneventfully, and 113 (29.2 %) broke down because of infection or dehiscence. Fifty-one (13.2 %) patients developed a postoperative SSI, and 62 (16.0 %) patients developed wound dehiscence. Gram-negative bacteria grew in 45 cultures (91.8 %) and included 38 cases of Escherichia coli. Previous radiation, rectum rupture, longer duration of surgery, and cerebrospinal fluid leakage were significantly associated with increased likelihood of developing an SSI. Previous radiation, rectum rupture, age <40 years, history of diabetes mellitus, maximum tumor diameter ≥ 10 cm, and instrumentation used were risk factors for wound complications. CONCLUSIONS: The incidence of wound complications is not so high at a musculoskeletal tumor center with surgeons experienced in treating sacral tumors. Controlling for these risk factors when possible may improve clinical outcomes.

Triple-layer reconstruction technique for large cribriform defects after endoscopic endonasal resection of anterior skull base tumors.

BACKGROUND: Endoscopic endonasal transcribriform (EET) resection of anterior skull base (ASB) tumors results in large defects that may extend the entirety of the cribriform plate. Endoscopic repair of these cribriform defects can often be challenging. We describe our reconstruction technique for large ASB defects after EET resection of ASB tumors. This triple-layer technique is comprised of autologous fascia lata, acellular dermal allograft, and a vascularized pedicled nasoseptal flap (PNSF). The technique is described and postoperative cerebrospinal fluid (CSF) leak rate is evaluated. METHODS: Retrospective review over a 2-year period identified 10 patients who underwent a purely EET approach for resection of ASB tumors. Patients who underwent combined cranionasal approaches and those treated for ASB encephaloceles were excluded from this study. After tumor resection, patients underwent triple-layer reconstruction using autologous fascia lata inlay, acellular dermal allograft inlay/overlay, followed by a PNSF to reconstruct the cribriform defect. No postoperative lumbar drainage was used. RESULTS: The average cribriform defect size was 9.1 (range, 5.0-13.8) cm(2) . All 10 patients underwent successful reconstruction with a postoperative CSF leak rate of 0% without the use of postoperative lumbar drainage. The mean follow-up period was 7.4 (range, 2-17) months. The mean age was 45.8 (range, 15-81) years with 30% of the patients being females. CONCLUSION: The triple-layer reconstruction technique is effective in reconstructing large ASB defects after endoscopic resection of the cribriform plate. We feel that the use of postoperative lumbar drainage is not necessary when using this repair technique.

Experience of video-assisted thoracoscopic resection for posterior mediastinal neurogenic tumours: a retrospective analysis of 58 patients.

INTRODUCTION: The objective of this study was to review the experience of video-assisted thoracoscopic resection of posterior mediastinal neurogenic tumours and to investigate the technical features and difficulties of this thoracoscopic approach. METHODS: From May 2001 to June 2011, 58 consecutive patients underwent thoracoscopic resection of posterior mediastinal tumours sequentially in our institution, including 36 males and 22 females. The median age of the patients was 38.7 years. The median tumour size was 4.9 cm. Twenty-four lesions were located at the left side, 33 lesions at the right side and 1 lesion at the bilateral side. All procedures generally required three ports, and intracapsular enucleation was preferred. For bulky tumours, dense adhesion and massive bleeding, conversion to thoracotomy was performed by extending the anterior incision to 6-10 cm. RESULTS: All procedures were successfully performed without death or serious complications occurring. The average operating duration was 127.2 min. The average intraoperative blood loss was 206.4 mL. The average chest tube drainage duration was 2.72 days. The average post-operative stay was 5.19 days. Fifty-three procedures were performed entirely under thoracoscopy to achieve gross total resection. There were five cases (8.6%) of conversion to thoracotomy procedure. Seven patients suffered from post-operative complications, including four Horner syndromes. No local recurrence occurred after an average follow-up of 44.9 months. CONCLUSION: Video-assisted thoracoscopic resections of the posterior mediastinal tumours were safe and reliable for selected patients with mastered thoracoscopic skills. Intracapsular enucleation was demonstrated to be a safe procedure. For tumours larger than 6 cm and located in the apex, the risk of the operation increased significantly.

Endoscopic resection of skull base tumours utilising the ultrasonic dissector.

OBJECTIVE: We report the use and benefits of the ultrasonic dissector in the resection of difficult skull base lesions. METHOD: Five case reports are presented, and the utilisation of ultrasonic dissectors in otorhinolaryngology is reviewed. RESULTS: The ultrasonic dissector was found to be a useful tool during the endoscopic resection of poorly accessible skull base tumours. Safe dissection and complete removal of all five lesions were achieved without any vascular injury. To our knowledge, this is the first report of the use of the ultrasonic dissector for the resection of sinonasal and skull base tumours. CONCLUSION: The ultrasonic dissector was found to be particularly useful during the endoscopic transnasal approach to the petrous apex. During minimally invasive endonasal surgery, benefits include the length of the instrument, speed and precision of dissection, and low risk of vascular injury.

Transoral robotic surgery for neurogenic tumors of the prestyloid parapharyngeal space.

The parapharyngeal space is a difficult area for a surgical approach due to anatomical complexity. We performed a minimally invasive and precise surgical technique to remove neurogenic tumors of the prestyloid parapharyngeal space using transoral robotic instrumentation. The mass was successfully removed in the two cases with three-dimensional visualization providing an excellent view of the resection margin and the dissection plane preserving the vital structures. An adequate resection margin was acquired, and no violation of the tumor capsule occurred. No significant complications were noted. Transoral robotic surgery was feasible for neurogenic tumors of the prestyloid parapharyngeal space, providing a sufficient resection margin and delicate dissection through excellent surgical views and instrumentation.

Intra-operative localisation of spinal level using pre-operative CT-guided placement of a flexible hook-wire marker.

Confident intra-operative localisation of thoracic spinal pathology remains challenging. Several strategies are routinely employed, including intra-operative fluoroscopy and pre-operative image-guided skin marking. These techniques are limited both by potential inaccuracy and inconvenience. Here we present a novel, efficient and accurate technique for intra-operative localisation of thoracic spinal pathology using pre-operative CT-guided placement of a flexible hook-wire marker.

Benign posterior mediastinal neurogenic tumors: results of a comparative study into video-assisted thoracic surgery and thoracotomy (13 years' experience).

OBJECTIVE: Mediastinal neurogenic tumors originate from the nerve tissues of the thorax and are generally located in the posterior mediastinum. The present study was performed to compare the results of thoracotomy with those of video-assisted thoracic surgery (VATS) for the surgical treatment of posterior mediastinal neurogenic tumors. METHODS: Twenty patients who underwent surgical resection for posterior neurogenic tumors between January 1996 and January 2009 were examined retrospectively. Thirteen (65%) patients were treated by thoracotomy (group T) and VATS was used in seven (35%) patients (group V). RESULTS: The duration of surgery was shorter in group V (83.5 ± 19 min) than in group T (124.6 ± 16.6 min; P < 0.0001). Chest drains were withdrawn earlier in group V (after 1 day) than in group T (1.6 ± 0.5 days; P = 0.005). The hospital stay was shorter for group V (1 day) compared with group T (3 ± 0.9 days; P < 0.0001) and group V required fewer analgesics than group T (P < 0.0001). CONCLUSION: VATS is the preferred treatment for posterior neurogenic tumors that show no preoperative signs of malignancy and do not involve the medulla spinalis.