Benign Schwannoma Research Articles

Clinical outcome after surgery on schwannomas in the extremities.

BACKGROUNDSchwannoma is a benign, encapsulated and slowly growing tumor originating from Schwann cells and is rarely seen in the peripheral nerve system. Typical symptoms are soreness, radiating pain and sensory loss combined with a soft tissue mass.AIMTo evaluate pre- and postoperative symptoms in patients operated for schwannomas in the extremities and investigate the rate of malignant transformation.METHODSIn this single center retrospective study design, all patients who had surgery for a benign schwannoma in the extremities from May 1997 to January 2018 were included. The location of the tumor in the extremities was divided into five groups; forearm, arm, shoulder, thigh and leg including foot. The locations of the tumor in the nerves were also categorized as either; proximal, distal, minor or major nerve. During the pre- and postoperative clinical evaluation, symptoms were classified as paresthesia, local pain, radiating pain, swelling, impairment of mobility/strength and asymptomatic tumors that were found incidentally (with magnetic resonance imaging). The patients were evaluated after surgery using the following categories: Asymptomatic or symptomatic patients (radiating and/or local pain) and those with complications. The follow up period was from the time of surgery until last examination of the particular physician. Multivariate logistic regression analysis was performed to identify independent prognostic factors for postoperative significant symptoms at follow-up.RESULTSWe identified 858 cases from the institutional pathology register. We excluded cases with duplicate diagnoses (n = 407), pathology not including schwannomas (n = 157), lesions involving the torso, spine and neck (n = 150) leaving 144 patients for further analysis. In this group 99 patients underwent surgery and there were five complications recorded: 2 infections (treated with antibiotics) and 3 nerve palsies (2 involving the radial nerve and one involving the median nerve) that recovered spontaneously. At the end of follow-up, 1.4 mo (range 0.5-76) postoperatively, we recorded a post-operative decrease in clinical symptoms: Local pain 76% (6/25), radiating pain 97% (2/45), swelling 20% (8/10). Symptoms of paresthesia increased by 2.8% (37/36) and there was no change in motor weakness before and after surgery 1% (1/1). Multivariate analysis showed that tumors located within minor nerves had a significantly higher prevalence of postoperative symptoms compared with tumors in major nerves (odds ratio: 2.63; confidence intervals: 1.22-6.42, P = 0.029). One patient with schwannoma diagnosed by needle biopsy was diagnosed to have malignant transformation diagnosed in the surgically removed tumor. No local recurrences were reported.CONCLUSIONSurgery of schwannomas can be conducted with low risk of postoperative complications, acceptable decrease in clinical symptoms and risk of malignant transformation is low.

Rare Schwannomas of Head and Neck and Review of Literature.

Benign schwannoma is a slow growing encapsulated tumor arising from the sheath of Schwann, The majority had extra-cranial localization. We report in this review three cases of a rare extra cranial localization of benign schwannoma in the trachea, frontal sinus and intraparotid facial nerve. The first case diagnosed in a 10-years-old boy, presented with a painless, slow growing mass evolving for three years in the left parotidic region, total conservative parotidectomy was done. The second case concerned a 38-years-old, was admitted to the emergency department with acute inspiratory dyspnea, endoscopic exploration revealed a polylobed tracheal tumor, complete tumor excision was done endoscopically. The third case was about a 33years old patient, presented a gradually enlarging frontal swelling associated with headache and left nasal obstruction, the endoscopic examination revealed a gray pinkish, smooth and firm soft tissue mass occupying the entire left nasal cavity, CT scan and MRI were requested to assess the characteristics and extent of the tumor, The surgical intervention combined two approaches: trans facial through a mid-frontal incision, and endonasal one. Histopathological examination confirmed the diagnosis of benign schwannoma in all these cases.

Long-Term Hearing Outcomes From Gamma Knife Treatment for Vestibulocochlear Nerve Schwannomas in a Large, Tertiary Care, Academic Hospital.

Describe long-term hearing outcomes with audiologic data with modern stereotactic radiosurgery techniques for vestibular schwannoma tumors. Since the mid-20th century, stereotactic radiosurgery has been an option for central nervous system tumors. Due to the non-invasive manner of treatment, this was extended to treatment for benign vestibular schwannomas without intracranial surgery. Modern advances have localized radiation and reduced dosage, but data are still lacking in the long-term hearing outcomes of this method of treatment. As one of the national leaders in this procedure, we present our full database of these outcomes over the full time period of our institutions utility of this modality. A retrospective review was performed of all patients undergoing stereotactic radiotherapy for vestibular schwannomas within the study period of 1998 to 2019 and their audiograms analyzed along with patient data. Laterality Gardner-Robertson hearing score changes were the primary outcome analyzed for each patient; and controls were placed to accommodate for patient demographic data. Long-term, multi-year audiometric evaluation showed statistically significant loss of serviceable hearing and reduction in hearing ability with the use of stereotactic radiosurgery for treatment of vestibular schwannomas. Little long-term data exists on the audiometric outcomes related to stereotactic radiosurgery treatment for vestibular schwannomas. Our institution has performed more than 300 stereotactic radiosurgery treatments showing a continued reduction over time in serviceable hearing. Practitioners should advise patients undergoing treatment for vestibular schwannomas with this treatment of long-term results.

Multiple schwannomas of the facial nerve mimicking cervical lymphoma: a case report

BackgroundIn this report, we describe the first case in literature of a patient with multiple schwannomas of the marginal mandibular branch of the facial nerve.Case presentationA Caucasian patient presented with a sudden onset of left lower facial nerve palsy House–Brackmann score III for 1 month. Computed tomography imaging was performed to exclude a cerebral event and revealed multiple tumors within the left parotid gland. Duplex ultrasound and magnetic resonance imaging scans delineated multiple, hypoechoic tumors, round in shape and well defined without a hilar structure along the left mandible. For histological verification, a left-side partial parotidectomy and extirpation of an intraparotideal node was performed with use of a nerve-integrity monitor. Histomorphological analysis of the resected tissue revealed a benign schwannoma. Facial nerve function remained unchanged since the operation. The size of the nonresected tumors is currently monitored regularly by ultrasonography. Fibromatosis has been excluded.ConclusionsIf multiple tumors occur in the parotid gland and the angle of the jaw, schwannomas need to be considered as a differential diagnosis. To plan the right diagnostic surgical intervention and prevent nerve damage, a thorough ultrasound examination is essential in preoperative diagnostic work-up for any suspicious lesion of the parotid gland and jaw region.

Varied foci of primary benign schwannoma of the thorax: a case series.

Schwannomas are the most common tumor of peripheral nerves. It comprises 1 to 2% of total thoracic tumor. Posterior mediastinum is the most common site in thorax. Hereby we are reporting two cases of schwannoma with different sites of origin. The classical presentation of schwannoma is an asymptomatic mass found on chest radiograph. This tumor is usually benign and slow growing. Imaging followed by histopathological examination is key to the diagnosis of this neoplasm. Resection of tumor cures the disease.

GIANT BENIGN SCHWANNOMA OF THE ANTERIOR BASE OF THE SKULL WITH SINONASAL AND PHARYNGEAL EXTENSION

Introduction: Schwannomas are tumors developed from Schwann cells present in the peripheral nerve sheaths. Their development both extra and intracranial is extremely rare. Observation: We report the case of a 36-year-old man who consulted for sinonasal syndrome evolving over the past ten years in which explorations found a large benign schwannoma of the anterior base of the skull with sinonasal and pharyngeal extension. The excision was performed externally by Moure and Sébileau with ENT and neurosurgery collaboration. The suites were simple. Discussion: The present observation again raises the question of the exact origin of developing sinonasal and endocranial schwannomas. The origin of the lesion and our management conditions were discussed. Conclusion: as for other authors, schwannoma should be considered in the diagnosis of skull base tumors. External surgery for extensive forms and ENT and neurosurgery collaboration help to minimize the risk of complications. Keywords: schwannoma; sinonasal schwannoma; skull base tumor.

PET/CT and contrast-enhanced CT imaging findings in benign solitary schwannomas

ObjectivesImaging features of positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced CT and pathological changes in benign solitary schwannoma were retrospectively analyzed, and the factors associated with high uptake of fluorodeoxyglucose (FDG) were examined. MethodsThe PET/CT, contrast-enhanced CT, and pathological results of 58 cases of benign solitary schwannomas confirmed by surgery or biopsy were retrospectively analyzed. The association of each variable with the maximum standardized uptake value (SUVmax) was evaluated. ResultsThe SUVmax of the 58 benign schwannoma cases was 4.1 ± 2.1 (1.5–11.1). When the locations of schwannomas were divided into gastrointestinal system/heart/abdominal and pelvic cavities/thoracic wall (type-1 locations) and other sites (type-2 locations), the schwannoma location was significantly correlated with the SUVmax (r = 0.538, p = 0.000). The SUVmax values were 5.8 ± 2.4 and 3.3 ± 1.5, respectively (p = 0.000). Peritumoral lymphoid cuffs were observed in 7 cases, 4 of which were tumors of gastrointestinal origin, accounting for 80 % of the gastrointestinal schwannomas (4/5). The presence of peritumoral lymphoid cuffs was significantly correlated with the SUVmax (r = 0.456, p = 0.000). The location of the schwannoma was significantly correlated with the presence of peritumoral lymphoid cuffs (r = 0.640, p = 0.000). We found that a peritumoral lymphoid cuff is strongly correlated with the presence of regional lymphadenopathy. Among the 7 cases showing peritumoral lymphoid cuffs, 5 cases had the presence of peritumoral enlarged lymph nodes. The degree of enhancement was significantly correlated with the SUVmax (r = 0.556, p = 0.000). ConclusionsBenign schwannomas originating from the gastrointestinal system/heart/abdominal location and showing the presence of peritumoral lymphoid cuffs or moderate and significant enhancement on contrast-enhanced CT were significantly associated with high FDG uptake. An accurate understanding of the factors associated with high FDG uptake can help reduce the misdiagnosis rate.

Schwannoma of the abdominal wall: updated literature review

Summary Background Schwannoma is a benign tumor arising from Schwann cells of the peripheral nerves. It is often asymptomatic and can develop in the retroperitoneum, mediastinum, head and neck region, and upper and lower extremities. Schwannoma of the abdominal wall is extremely rare, but differential diagnosis with malignant neoplasms is important to reduce the risk of undertreatment. Methods A narrative review of abdominal wall schwannoma was performed using PubMed, EMBASE, and Web of Science database and the search terms “schwannoma”, “neurinoma”, “neurilemmoma”, “soft tissue tumors”, “neurogenic tumor”, “rectus abdominis mass”, “abdominal wall”. In addition, the hospital charts were reviewed to report the personal experience. Results Only 9 single case-reports of benign schwannoma of the abdominal wall were found in the English medical literature over the past decade. None of the patients received preoperative biopsy and all were resected with clear margins. In addition to the literature review, we report the case of a 58-year-old man referred for a palpable mass in the left upper abdominal quadrant. Ultrasonography and magnetic resonance imaging revealed a solid and well-encapsulated mass inside the left rectus abdominis muscle. A core biopsy of the lesion provided the diagnosis of cellular schwannoma and this was confirmed by histopathologic examination of the surgical specimen. Conclusions Benign schwannoma of the abdominal wall is extremely rare. Percutaneous core needle biopsy is important for the differential diagnosis with more common and biologically more aggressive malignancies, such as desmoid tumors and sarcomas, and may be relevant for planning the most appropriate management.

Gamma Knife Radiosurgery for Large Vestibular Schwannoma More Than 10 cm 3 : A Single-Center Indian Study.

Introduction Gamma Knife radiosurgery (GKRS) is an effective treatment for benign vestibular schwannomas (VSs). The established cutoffs have recently been challenged, as recent literature expanded the horizon of GKRS to larger tumors. Even though microsurgery remains the primary option for large VS, GKRS can provide reasonable tumor control and is more likely to avoid cranial neuropathies associated with open surgery. Methods We analyzed patients with VS with volume exceeding 10 cm 3 who underwent GKRS at our center from January 2006 to December 2016. Clinicoradiological and radiosurgical data were collected from medical records for statistical analysis. Follow-up was performed every 6 months with a clinical assessment along with magnetic resonance imaging (MRI) of the brain and audiometric evaluation in patients with serviceable hearing. Results The study included 34 patients (18 males and 16 females) with an average age of 45.5 years. The mean tumor volume was 10.9 cm 3 (standard deviation [SD], ± 0.83), with a median tumor dose of 12 Gy (interquartile range, 11.5-12) and a mean follow-up of 34.7 months (SD, ± 23.8). Tumor response was graded as regression in 50%, stable in 44.1%, and increase or GKRS failure in 2 cases (5.8%). Treatment failure was noted in five cases (14.7%), requiring microsurgical excision and a ventriculoperitoneal shunt post-GKRS. The tumor control rate for the cohort is 85.3%, with a facial preservation rate of 96% (24/25) and hearing loss in all (5/5), while three patients developed new-onset hypoesthesia. We noted that gait ataxia and involvement of cranial nerve V or VII at initial presentation were associated with GKRS failure in univariate analysis. Conclusion Microsurgery should remain the first-choice treatment option for large VSs. GKRS is a viable alternative with good tumor control and improved or stabilized cranial neuropathies with a low complication rate.

Large benign schwannoma of the greater omentum with synchronous cervical cancer: A case report.

Introduction and importanceSchwannomas are uncommon tumors of the omentum with only 16 reported cases originating from the greater omentum in the literature. We report for the first time a synchronous presentation of an omental schwannoma and cervical cancer.Case presentationA 37-year-old female presented with an abdominal mass and heavy vaginal bleeding. An 11.5 × 14.6 × 16.6 cm complex omental mass and 5.4 × 6.2 × 4.4 cm lobulated heterogeneous cervical mass were noted on CT-scan. Wide excision of the complex mass and radical hysterectomy with bilateral salpingo-oophorectomy and pelvic lymph node dissection was performed. The final biopsy revealed benign omental schwannoma and poorly differentiated cervical adenocarcinoma.Clinical discussionSchwannomas originating from the greater omentum are less common than in the lesser omentum due to the paucity of nervous tissue in the former. They can undergo malignant transformation and the most common presentation is abdominal pain/discomfort. Larger tumors may cause catastrophic bleeding. Prompt surgery should be offered and wide local excision with sufficient margins be performed when there is suspicion of malignancy. Schwannomas presenting with multiple or synchronous lesions are commonly associated with neurofibromatosis type 2, schwannomatosis, and Carney's complex. Whether this co-occurrence is simply incidental or has a causal relationship remains to be established.ConclusionBenign schwannoma of the greater omentum is rare and only requires complete tumor excision. However, surgeons should be aware that synchronous presentation of cervical cancer is possible and that thorough examination of both sites should be undertaken when either primary tumor presents.

Diagnostic Dilemma of Retroperitoneal Schwannomas Encountered in a Specialized Gynecology Hospital

Background: This study analyzed the potential diagnosis and therapeutic challenges of retroperitoneal schwannoma (RSs) in a specialized gynecology hospital. Methods and materials: A retrospective review was performed in our hospital from 2000 to 2018. A literature search of RSs was conducted using PubMed database. Results: 45 patients were identified (22 from our hospital and 23 from the literature review). The majority of patients presented asymptomatic (22/45). Among them, 25 cases were misdiagnosed as adnexal cysts, 13 uterine fibroids, 1 ovarian malignancy and 6 pelvic masses. Intraoperative exploration revealed that the masses were located in the retroperitoneal space. The median diameter was 6.2 cm (range 3.0–9.8 cm) in our hospital compared with 9.3 cm (6–15 cm) in literature review. Complete resection was performed in 37 patients and subtotal resection in 8 patients. The pathological results confirmed the diagnosis of benign schwannoma and no recurrence was found in the follow-up data. Conclusion: The preoperative diagnosis of RSs is difficult to make because of its nonspecific characteristics. In a specialized gynecology hospital, it is more important to differentiate the benign and malignant of mass before surgery. Surgical complete resection of tumor is recommended and recurrence is unusual after complete resection.

Left atrial schwannoma in schwannomatosis: a case report

BackgroundPrimary cardiac schwannoma in the left atrium and schwannomatosis are rare diseases.Case presentationWe report the case of a 46-year-old asymptomatic man who had tumor resection for parapharyngeal schwannoma at another institute 1 year ago. He was presented to our hospital for further evaluation of an abnormal cardiac shadow that was found incidentally. Computed tomography and transesophageal echocardiography revealed a cardiac tumor originating from the posterior wall of the left atrium, an atrial septal defect, and two other mediastinal tumors. The cardiac mass was completely excised with normal margins of the surrounding atrial wall. The post-resection defect and atrial septal defect were repaired using bovine pericardium. Pathological findings were compatible with benign schwannoma, and a diagnosis of schwannomatosis was made based on his medical history.ConclusionPrimary cardiac schwannoma is an exceedingly rare tumor, and the incidence in schwannomatosis has not been reported in the literature.

Schwannome bénin primitif de la plèvre : à propos de deux cas opérés

The preferred thoracic location of a schwannoma is the posterior mediastinum. A pleural location is very rare. To date there have been fewer than 20 cases in the literature. We report two operated cases of primary benign pleural schwannoma. The first occurred in a 52-year-old woman who presented with right-sided chest pain and chronic cough. The radiological appearance suggested a hydatid cyst of the lower right lobe. The second case concerned a 37-year-old, asymptomatic man with no past history, who presented with a left posterior mediastinal mass, discovered incidentally on imaging. Both patients underwent complete surgical resection via a posterolateral thoracotomy. The final anatomo-pathological investigation revealed two primary benign schwannomas of the pleura.

A Rare Case of Retroperitoneal Schwannoma: A Case Report

Abdominal schwannomas are a very rare entity and retroperitoneal schwannomas even more so. Here, we present the case of a 59-year-old male. The patient presented with undiagnosed intermittent pain abdomen. Workup and imaging revealed a well-defined solid cystic mass in the retroperitoneal lumbar region compressing the inferior vena cava. There was no evidence of disseminated disease. Laparotomy was done and the mass was excised. Histological examination revealed a benign schwannoma. The patient had an uneventful post-operative period and was discharged and is currently on follow-up.

Comparative analysis within diagnostics and treatment of retroperitoneal schwannoma

Introduction: Retroperitoneal schwannoma is a rare tumor that originates from the Schwann cells of the peripheral nerve sheath. It is mostly located in the brain and spinal cord, but can affect other untypical places such as the scrotum and penis. Aim: The aim of this study was to present two different cases of retroperitoneal schwannoma. Case study: The authors present two cases of patients with benign and malignant retroperitoneal schwannomas (malignant peripheral nerve sheath tumor – MPNST). Results and discussion: It has been reported that only 0.7% of schwannomas occur in the retroperitoneum. It is difficult to diagnose this tumor preoperatively because of the clinical variety and a lack of the characteristic symptoms. These tumors can mimic different conditions, such as pancreatic tail tumors, a hepatic tumor in the caudate lobe, or lymph node metastases. They can arise at any age, but generally occur between 30 and 50 years of age and develop in any race. Based on the literature published in the last 20 years regarding schwannomas arising in retroperitoneum 20 cases were reported. Conclusions: Careful monitoring is highly recommended after retroperitoneal schwannoma removal.

Peripheral nerve tumor, a differential diagnosis with primary neural leprosy


 From December 1999 to May 2015, five patients with nerve tumors were sent to Lauro de Souza Lima Institute. It was suspected that they suffered from primary neural leprosy towards the tuberculoid clinical form, a prevalence of 4.5:10000 among the new patients assessed during the study period. All of the patients had similar clinical conditions characterized by mononeuropathy with nerve tumor associated with pain, absence of skin lesions and positive Mitsuda reaction. The authors report the main clinical characteristics and complementary tests: immunologic investigation of Mitsuda’s reaction and the antigen Phenolic GlicoLipid-1 test (PGL-1), bacilloscopic index, neurophysiologic study and image procedures. All patients were submitted to tumor resection and anatomopathological study. Four out of the five patients were diagnosed with peripheral nerve tumor (one of them with malignant schwannoma, two of them with benign schwannomas and the other with neural fibrolipoma), whereas the fifth patient was diagnosed with tuberculoid leprosy

Laparoscopic resection of a primary diaphragmatic schwannoma: a case report and literature review

BackgroundSchwannomas are nerve sheath tumors that commonly originate from the stomach and small intestine. A primary schwannoma of the diaphragm is rare and does not show any symptoms until it grows to a certain size. Hence, it is extremely rare that it was found at a size that allowed resection under videoscopic surgery.Case presentationA 77-year-old woman was referred to our department for surgical treatment of a tumor located near the gastric fornix. She underwent a routine esophagogastroduodenoscopy 2 years and 7 months prior to the referral. It was suspected that she had a submucosal tumor measuring 10 mm, located in the fornix, and was then referred to her previous physician. During her follow-up, endoscopic ultrasonography (EUS) revealed that the cystic structure had continued to grow toward the gastric wall, and she was then referred to the endoscopy division of our hospital. She continued to be followed-up, and it was noted that the tumor was gradually increasing in size. Therefore, she requested surgical resection, and was finally referred to our division. Since the tumor was rather small, we planned a laparoscopic surgery. An initial examination during the operation revealed that the tumor was located on the left diaphragm. Since the tumor was relatively small and visibility was good, we decided to continue with the laparoscopic surgery. Partial diaphragmectomy with complete inclusion of the tumor was performed, and the defect of the diaphragm was directly closed by a running suture. Pathological examination revealed a benign schwannoma that had originated from the diaphragm. To support our findings, we also reviewed the scientific literature on diaphragmatic schwannoma cases reported up to April 2020.ConclusionsIn this extremely rare case, we successfully resected the diaphragmatic schwannoma using laparoscopic surgery.

Robot-Assisted Nerve-Sparing Excision of a Symptomatic Obturator Nerve Schwannoma: A Case Report

Reports in the literature have presented the feasibility of a minimally invasive resection of retroperitoneal or pelvic schwannomas. However, there are only a few reports in the literature about a robot-assisted nerve-sparing approach towards obturator schwannomas.We present a case of a concomitant excision of a symptomatic obturator nerve schwannoma in a patient undergoing robot-assisted radical prostatectomy with pelvic lymphadenectomy. The patient complained about an ongoing, low-grade sensory dysfunction in the left proximal thigh area, without loss of muscular function. A preoperative pelvic MRI incidentally showed a thickening of the left obturator nerve of about 1 cm. During pelvic lymphadenectomy, the thickening was identified, an axial incision was made to the nerve sheath, and a small tumor mass (9 mm x 5 mm x 3 mm) was excised, thereby decompressing the nerve fibers and simultaneously preserving the continuity of the obturator nerve. The nerve sheath was closed using a 7-0 monofilament suture. Frozen section biopsy that was undertaken during the surgical procedure excluded the presence of a malignancy.There were no intra- or postoperative complications. Postoperatively, the patient described a temporary sensory dysfunction of the left inner-thigh area, which regressed completely. The histopathological result confirmed a benign schwannoma of the obturator nerve. In experienced hands, the robot-assisted approach appears safe and feasible as a technique to excise a schwannoma of the obturator nerve, without the need to proceed to a full nerve resection.

Laparoscopic nephrectomy for giant benign renal schwannoma: a case report and review of literature

Benign giant renal schwannoma is rarely found and the diagnosis difficulty only depends on physical and imagological examination. Pathological examination is essential to confirm the diagnosis of renal schwannoma. Nephrectomy and tumorectomy are primary treatments for renal schwannoma. Although most of the reported patients present satisfactory outcome, however, there is still not sufficient evidence to reveal the biological characteristics and post-operation recurrence rate of renal schwannoma. Herein, we report a rare case of giant and complicated renal schwannoma. A 56-years-old female patient was admitted to the urology department due to left lower back pain for approximately 5 days. No positive signs and other special abnormalities were found. CT scan presented a soft tissue tumor with inhomogeneous enhanced in the renal hilum. Surgery was performed to excise the tumor and left renal. Renal schwannoma was confirmed by pathological examination. At the 6-month follow-up, no evidence of recurrence was found. Our present report could provide more material for further study.

A Rare Case of Malignant Peripheral Nerve Sheath Tumor of Larynx.

Malignant peripheral nerve sheath tumors are highly aggressive tumors and they arise either de novo or from preexisting benign schwannoma or neurofibromatosis. Malignant peripheral nerve sheath tumor of the larynx is an extremely rare neoplasm, for which accurate diagnosis is difficult and the therapy is usually delayed. Although wide surgical excision is the mainstay of treatment, radiation therapy also plays an important role in the control and treatment of locally recurrent disease and non resectable cases. Here we are reporting a case of malignant peripheral nerve sheath tumor of the larynx without definite evidences of von Recklinghausen's disease or preexisting benign peripheral nerve sheath tumor.