Nerve tumors of the hand and upper extremity

Multimodality imaging review of ulnar nerve pathologies

The ulnar nerve is the second most commonly entrapped nerve after the median nerve. Although clinical evaluation and electrodiagnostic studies remain widely used for the evaluation of ulnar neuropathy, advancements in imaging have led to increased utilization of these newer / better imaging techniques in the overall management of ulnar neuropathy. Specifically, high-resolution ultrasonography of peripheral nerves as well as MRI has become quite useful in evaluating the ulnar nerve in order to better guide treatment. The caliber and fascicular pattern identified in the normal ulnar nerves are important distinguishing features from ulnar nerve pathology. The cubital tunnel within the elbow and Guyon's canal within the wrist are important sites to evaluate with respect to ulnar nerve compression. Both acute and chronic conditions resulting in deformity, trauma as well as inflammatory conditions may predispose certain patients to ulnar neuropathy. Granulomatous diseases as well as both neurogenic and non-neurogenic tumors can also potentially result in ulnar neuropathy. Tumors around the ulnar nerve can also lead to mass effect on the nerve, particularly in tight spaces like the aforementioned canals. Although high-resolution ultrasonography is a useful modality initially, particularly as it can be helpful for dynamic evaluation, MRI remains most reliable due to its higher resolution. Newer imaging techniques like sonoelastography and microneurography, as well as nerve-specific contrast agents, are currently being investigated for their usefulness and are not routinely being used currently.

High-frequency ultrasound imaging findings in the diagnosis of segmental schwannomatosis of the ulnar nerve: case report and literature review

Schwannomatosis is characterized by the development of multiple schwannomas without evidence of vestibular tumors. Segmental schwannomatosis is defined as being limited to one limb or five or fewer contiguous segments of the spine. We report a case of a 20-year-old male with the painful masses of the left upper extremity with associated numbness and paresthesia in the ulnar nerve distribution. The high-frequency ultrasound showed that the ulnar nerve fascicles were enlarged and expanded with beadlike growth. The patient underwent surgery twice and all the tumors were pathologically confirmed to be schwannomas. Together, the medical history, imaging, and pathology findings indicated the diagnosis of segmental schwannomatosis. By the imaging diagnostic tools, MRI is the most commonly used in assistance with diagnosis of segmental schwannomatosis while high-frequency ultrasonography is rare. In this paper, we discuss the value of high-frequency ultrasonography in the diagnosis of this rare disease. This case report provides a deeper understanding of segmental schwannomatosis and may help improve the accuracy of preoperative diagnosis.

Surgery of Schwannoma in the upper limb - sensitivity and specificity of preoperative magnetic resonance imaging and relation between tumour size and symptoms

BACKGROUND

Benign peripheral nerve tumours consist of different types, most commonly Schwannomas. Preoperative Magnetic Resonance Imaging (MRI) is commonly performed before surgery and Pathoanatomical Diagnosis (PAD) confirms the diagnosis. Our aims were to study the utility of MRI and the relation between tumour size and symptoms.

METHODS

Retrospectively, patients, surgically treated for benign nerve tumours between 2008 and 2019, were identified and preoperative MRI, with measurement of tumour size, PAD, symptoms, peroperative details, and symptomatic outcomes of surgery, were analysed.

RESULTS

The sensitivity and specificity to correctly identify Schwannomas with preoperative MRI were 85% and 50%, respectively, based on 30 Schwannomas and nine neurofibromas that were identified. Tumour size did not affect the presence of preoperative symptoms, but patients with sensory dysfunction at last follow-up had larger Schwannomas (p < 0.05). Symptoms as a palpable tumour, paraesthesia and pain improved by surgical excision (p < 0.001, p < 0.001 and p < 0.012, respectively), but sensory and motor dysfunction were common postoperatively. No malignant peripheral nerve sheath tumours (MPNST) were found. Using a surgical microscope, instead of only loop magnification, lowered the risk of perioperative nerve injuries (p < 0.05), but did not further diminish postoperative symptoms.

CONCLUSIONS

Early and accurate diagnosis of Schwannomas is valuable for adequate presurgical preparation and prompt surgical intervention. Preoperative examination with MRI has a high sensitivity, but low specificity; although recent advancement in MRI technology indicates improvement in diagnostic precision. Surgical excision is preferably performed early in conjunction with symptomatic debut to improve outcome.

Benign nerve tumours in the upper limb: a registry-based study of symptoms and surgical outcome

Surgery for benign nerve tumours is performed for pathoanatomical diagnosis and symptomatic relief, but might cause residual problems. We aimed to assess patient-reported symptoms and disability before and after surgery at a national level. In total, 206 cases surgically treated for a benign peripheral nerve tumour 2010-2019 registered in the Swedish Quality Registry for Hand Surgery (HAKIR; response rates 22-34%) were analysed. Surgery reduced overall disability in the affected limb (QuickDASH 18/100 [IQR 5-36] preoperatively and 5/100 [IQR 0-22] 12 months postoperatively), improved ability to perform daily activities (HQ-8; 11/100 [IQR 0-50] preoperatively and 0/100 [IQR 0-20] 12 months postoperatively) and decreased three evaluated pain modalities: pain at rest (HQ-8; 20/100 [IQR 0-40] preoperatively and 0/100 [IQR 0-10] 12 months postoperatively), pain on motion without load (HQ-8; 20/100 [IQR 0-40] preoperatively and 0/100 [IQR 0-10] 12 months postoperatively), and pain on load (HQ-8; 24/100 [IQR 1-69] preoperatively and 1/100 [IQR 0-30] 12 months postoperatively). Cold sensitivity was a minor problem both before and after surgery (HQ-8; 0/100 [IQR 0-30] preoperatively and 1/100 [IQR 0-40] 12 months postoperatively). We conclude that surgery for benign peripheral nerve tumours provides good symptomatic relief with low risk for residual problems.

Ultrasonography of peripheral nerve tumours: a case series

BACKGROUND

Peripheral nerve tumours (PNTs) are rare, but important cause of peripheral nerve dysfunction. The aim of the study was to present a series of consecutive patients with PNTs evaluated in authors' ultrasonography (US) practice.

PATIENTS AND METHODS

The electronic medical records of patients with PNTs examined at our US laboratory from February 2013 to May 2020 were retrospectively reviewed. Data on gender, age, clinical features, PNT location, electrodiagnostic (EDx) features and US findings were collected.

RESULTS

In the analyzed period 2845 patients were examined in our US laboratory. From these 15 patients (0.5%) with PNTs were identified. Four of them (3 with confirmed neurofibromatosis) had multiple PNTs. Half of patients (53%) presented with features of peripheral nerve damage, and others with palpable mass or pain. The most often involved nerve was ulnar (36%). PNT cross sectional areas varied from 24 mm² to 1250 mm² (median, 61 mm²). Based in 5 patients on histological and in remaining patients on US features, schwannoma was diagnosed in 40%, neurofibroma in 27%, and perineurioma in 27% of patients.

CONCLUSIONS

As in previous reports, PNTs in our series presented with neurological symptoms, palpable mass or pain. In contrast to other focal neuropathies, particularly nerves with schwannomas, in spite of their large thickening, often demonstrated well preserved function. Adding US to our clinical practice, enabled us to diagnose these rare peripheral nerve lesions that we missed before.

Rare Tumors Causing Median Nerve Compression in Adults-A Narrative Review

The median nerve can be compressed due to a tumor along the course of the median nerve, causing typical compression symptoms or even persistence or recurrence after an operation. The aim of this review is to provide a comprehensive overview of rare tumors described in recent publications that cause median nerve compression and to evaluate treatment options. The PubMed, Embase, and Web of Science databases were searched for studies describing median nerve compression due to a tumor in adults, published from the year 2000 and written in English. From 94 studies, information of approximately 100 patients have been obtained. Results  The rare tumors causing compression were in 32 patients located at the carpal tunnel, in 21 cases in the palm of the hand, and 28 proximal from the carpal tunnel. In the other cases the compression site extended over a longer trajectory. There were 37 different histological types of lesions. Complete resection of the tumor was possible in 58 cases. A total of 8 patients presented for the second time after receiving initial therapy. During follow-up, three cases of recurrence were reported with a mean follow-up period of 11 months. The most common published cause of median nerve compression is the lipofibromatous hamartoma. Besides the typical sensory and motor symptoms of median nerve compression, a thorough physical examination of the complete upper extremity is necessary to find any swelling or triggering that might raise suspicion of the presence of a tumor.

Diffuse Type Neurofibroma of the Forearm

Nerve sheath tumors comprise 5% of soft tissue masses of the upper limb in adults. Neurofibromas are divided into three types: localized, diffuse, and plexi- form. The diffuse type is rare and is typically found in the head and neck region. We present a rare case of diffuse type neurofibroma found in the forearm, presented to our clinic as a slowly enlarging mass of the left forearm of 3 years duration. The lesion was suspicious in the magnetic resonance imaging, and biopsy revealed diffuse type neurofibroma. We opted for total excision of the lesion that was found to be not possible due to involvement of the major nerves. The final pathology report showed no malignancy. Nerve tumors of the upper limb can be either benign or malignant. Neurofibroma associated with neurofibromatosis has malignant potential. The diffuse type is rare, and it most commonly occurs in the head and neck region. It has a low malignant transformation rate. Magnetic resonance imaging is the diagnostic modality of choice; however, it can be inconclusive. Biopsy should be taken to confirm the diagnosis and plan for management. Our case was managed by near total excision in order to preserve the major forearm nerves because of high clinical suspicion.

[The use of intraoperative fascicle-topographic electromyography in peripheral nerve surgery: review of the literature and clinical experience]

The intraoperative assessment of a pathological nerve segment is crucial in peripheral nerve surgery. Based on different techniques the function of a peripheral nerve is analyzed and either a neurolysis alone or a resection with subsequent nerve reconstruction is performed. Beside the morphological and histological assessment or the use of a nerve stimulator, intraoperative electrophysiology is highly useful. The aim of this diagnostic tool is the recording of objective parameters, documenting the function of peripheral nerves. Intraoperative electroneurography allows the assessment of a nerve action potential over a pathological nerve segment and has been used for decades. In contrast, additional needle electromyography is rarely used even though this technique is characterized by interesting advantages: It is very helpful for the selection of donor fascicles during neurotization surgeries and for the electrophysiological assessment of neuromata in continuity. In the present review, we discuss the value of intraoperative electromyography in the treatment of peripheral nerve trauma as well as peripheral nerve tumors.

Surgical Excision of a Giant Schwannoma of the Hand: A Case Report

CASE

We report a 78-year-old man who underwent excision of a 13-year-old benign schwannoma originating from the terminal motor branch of the ulnar nerve. The mass measured 13 cm in diameter on presentation and was successfully excised, preserving a functional hand. At 4-year follow-up, the patient was asymptomatic with intact motor and sensory function and no signs of recurrence. To the best of our knowledge, this is the largest schwannoma of the hand to be reported in the literature.

CONCLUSIONS

Large schwannomas of the hand can successfully be excised with no postoperative complications.

Peripheral nerve tumors of the hand: Clinical features, diagnosis, and treatment

The majority of the tumors arising from the peripheral nerves of the hand are relatively benign. However, a tumor diagnosed as malignant peripheral nerve sheath tumor (MPNST) has destructive consequences. Clinical signs and symptoms are usually caused by direct and indirect effects of the tumor, such as nerve invasion or compression and infiltration of surrounding tissues. Definitive diagnosis is made by tumor biopsy. Complete surgical removal with maximum reservation of residual neurologic function is the most appropriate intervention for most symptomatic benign peripheral nerve tumors (PNTs) of the hand; however, MPNSTs require surgical resection with a sufficiently wide margin or even amputation to improve prognosis. In this article, we review the clinical presentation and radiographic features, summarize the evidence for an accurate diagnosis, and discuss the available treatment options for PNTs of the hand.

Bilateral Plexiform Neurofibromas of the Posterior Interosseous Nerve Mimicking Dorsal Wrist Ganglions

A 33-year-old woman presented with bilateral dorsal wrist masses associated with pain and limited range of motion. On initial presentation, the masses were believed to be ganglion cysts and the patient opted for observation. Three years later, she was found to have a chest wall mass diagnosed by biopsy to be a neurofibroma. When she later returned to seek treatment for her wrist masses, magnetic resonance imaging demonstrated posterior interosseous nerve (PIN) neurofibromas. Dorsal wrist masses situated over the scapholunate interval are commonly attributed to ganglion cysts. Neurofibromas of the PIN, although rare, should be considered in the differential diagnosis when a mass elicits pain with percussion, fails to transilluminate, fails aspiration, or if the patient has a history of neurofibromas elsewhere in the body.

Nerve Sheath Myxoma: A rare tumor, a case report and literature review

INTRODUCTION

Nerve Sheath Myxoma is a rare benign nerve sheath tumor, commonly seen in young adults. Patients usually present with a small nodule commonly affecting upper and lower limbs. Nerve Sheath Myxoma has not been reported in children below the age of 1 year.

CASE PRESENTATION AND METHODS

We present the first reported case of Nerve Sheath Myxoma (NSM) in the hand in a 4-month old child in line with the SCARE 2018 criteria.

DISCUSSION

NSM is difficult to diagnose using standard imaging technique; Magnetic Resonance Imaging (MRI) and Ultrasonography (USS) cannot differentiate it from vascular anomalies.

CONCLUSION

Soft tissue tumors in the hand of pediatric population are difficult to diagnose. Formal excision of the tumor by a specialized pediatric hand surgeon and histopathological analysis were the only avenue to correctly diagnose the NSM.

Retrospective Analysis of 20 Patients Affected by Schwannomas in the Upper and Lower Limbs

Objective  To analyze the epidemiological profile and evolution of 20 patients diagnosed with upper- and lower-limb schwannomas.

Methods  A group of patients was defined for a retrospective evaluation comprising the period between February 2002 and June 2018, in which we studied and evaluated 20 medical records of patients undergoing surgery due to schwannoma; the diagnosis was confirmed by an anatomopathological examination.

Results  Male and female patients were equally affected. The average age was 50.85 years, ranging from 12 to 77 years. There was a predominance of the upper limb and of the flexor face. The most affected nerve was the ulnar nerve. In total, 6 (30%) patients had transient postoperative complications. No cases of tumor recurrence were identified.

Conclusion  Schwannoma is a rare and difficult-to-diagnose lesion. It should always be considered as a hypothesis when facing a soft-tissue tumor affecting the limbs. The Tinel sign should be regarded, given its higher correlation with complications. The patients should be informed of the possible postoperative complications, which are frequent but usually transient.

Benign peripheral nerve sheath tumor of digit versus major-nerve: Comparison of MRI findings

Objective

To compare the symptoms and magnetic resonance imaging (MRI) findings between digital peripheral nerve sheath tumor (PNST) and major-nerve PNST.

Methods

A total 36 cases with benign PNSTs (16 digital, 20 major-nerve) were enrolled. Chief complaint and Tinel sign were reviewed. Five classic MRI features of PNST, the signal intensity (SI), the enhancement, and the shape of tumor were evaluated on MRI.

Results

Half of each group showed tenderness. Tinel sign was less frequent in digital PNST (12.5%) than major-nerve PNST (95.0%, P < 0.001). Split fat sign, entering and exiting nerve, target sign, and thin hyperintense rim were only observed in major-nerve PNST (P = <0.001, <0.001, 0.492, and 0.002, respectively). Fascicular sign was found in digital PNSTs (31.3%), but more frequent in major-nerve PNST (P < 0.001). In digital PNSTs, mild hyperintense SIs (56.2%) on T1-weighted images (T1-WI) was noted, but none in major-nerve PNST (P < 0.001). Both groups showed hyperintense SIs on T2-WI (P = 0.371). Homogeneity on T2-WI was noted in 43.8% of digital PNSTs, but none in major-nerve PNSTs (P = 0.004). Both groups showed heterogeneous enhancement (P = 0.066), but four (25%) digital PNSTs showed homogeneous enhancement. Lobulated shape was noted in 50% of digital PNSTs but none of major-nerve PNSTs (P = 0.001). Digital nerve was involved at 81.3% of digital PNSTs. Three foot cases showed unusual manifestations: bone destruction, skin thickening, and subungual location.

Conclusion

In digital PNSTs, Tinel sign is not commonly found and classic MRI findings is insufficient. In addition, some digital PNSTs show different SI and enhancement from major-nerve PNSTs. However, digital soft tissue tumor involving digital neurovascular bundle and especially representing a fascicular sign should be considered the possibility of a digital PNST.

Rare Schwannoma Nerve Tumor in a Lesser Toe: A Case Report

A schwannoma is a solitary benign tumor composed of Schwann cells occurring anywhere in the peripheral nervous system. The diagnosis of a schwannoma is often difficult to make by clinical presentation and advanced imaging modalities. We present a case report of a 61-year-old Hispanic woman with a left-foot, third-digit, soft-tissue mass. The diagnosis of a schwannoma of the proper digital nerve was made postsurgically by means of histopathologic and immunohistochemistry parameters. This is a rare location for a schwannoma, and neurogenic tumor should be included in the differential diagnosis of soft-tissue mass, as there have been prior case reports.

Atypical schwannoma of the median nerve. A case report

Schwannomas of the hand are very rare tumors and represent less than 3% of all soft tissue tumors in the hand. These tumors share clinical, epidemiological and imaging characteristics with the other soft tissue and peripheral nerve tumors; thus, it can be difficult to make a preoperative diagnosis. Here we report the case of a 48-year-old woman who presented with a schwannoma arising from the palmar branch of the median nerve. The tumor measured 54 × 41 x 52 mm and was located in the thenar eminence. The first hypothesis was a vascular tumor. After surgery and histological analysis, the final diagnosis of an atypical schwannoma was established. The presence of shared immunohistochemical characteristics with cellular histiocytoma and myoepithelial tumors forced us to adopt an aggressive follow-up protocol. As of the last follow-up at 9 years, the patient had good clinical outcomes and no recurrence. This case highlights the difficulties encountered in clinical practice to diagnose such tumors.

Application of diffusion tensor imaging (DTI) and MR-tractography in the evaluation of peripheral nerve tumours: state of the art and review of the literature

Peripheral nerves can be affected by a variety of benign and malignant tumour and tumour-like lesions. Besides clinical evaluation and electrophysiologic studies, MRI is the imaging modality of choice for the assessment of these soft tissue tumours. Conventional MR sequences, however, can fail to assess the histologic features of the lesions. Moreover, the precise topographical relationship between the peripheral nerve and the tumor must be delineated preoperatively for complete tumour resection minimizing nerve damage. Using Diffusion tensor imaging (DTI) and tractography, it is possible to obtain functional information on tumour and nerve structures, allowing the assess anatomy, function and biological features. In this article, we review the technical aspects and clinical application of DTI for the evaluation of peripheral nerve tumours. (www.actabiomedica.it)

Schwannoma of the Palmar Cutaneous Branch of the Median Nerve

Peripheral schwannomas are benign tumors originating from the Schwann cells of the peripheral nerve sheath. They make up a small percentage of the overall incidence of tumors of the hand, most commonly involving the ulnar nerve. The authors report a case of a 59-year-old patient with a slowly enlarging mass over his right wrist and no other symptoms. During surgery, a schwannoma involving the palmar cutaneous branch of the median nerve was found and successfully removed. This is a rare clinical entity, with few cases reported in the literature. In the current case, the lesion did not cause significant symptoms, and the authors demonstrated successful surgical enucleation of the lesion without complication. [Orthopedics. 2018; 41(4):e572-e573.].

Acquired digital fibrokeratoma: review of its clinical and dermoscopic features and differential diagnosis

Acquired digital fibrokeratoma (ADFK) is a rare, benign, fibrous tumor that most often occurs on fingers. It may resemble a rudimentary supernumerary digit and is often misdiagnosed as another common benign condition, such as common wart. It is typically asymptomatic and occurs as a solitary nodule less than 1 cm in diameter. Oftentimes ADFK shares clinical and/or histologic resemblance with other benign and malignant cutaneous conditions so it is crucial that careful examination is undertaken. In this article, we will discuss the clinical presentation, epidemiology, etiology, dermoscopic and histologic findings, management, and differential diagnoses for ADFK, with the hope that this review will facilitate timely diagnosis and management for this distinct condition.

Magnetic Resonance Imaging Appearance of Schwannomas from Head to Toe: A Pictorial Review

Schwannomas are benign soft-tissue tumors that arise from peripheral nerve sheaths throughout the body and are commonly encountered in patients with neurofibromatosis Type 2. The vast majority of schwannomas are benign, with rare cases of malignant transformation reported. In this pictorial review, we discuss the magnetic resonance imaging (MRI) appearance of schwannomas by demonstrating a collection of tumors from different parts of the body that exhibit similar MRI characteristics. We review strategies to distinguish schwannomas from malignant soft-tissue tumors while exploring the anatomic and histologic origins of these tumors to discuss how this correlates with their imaging findings. Familiarity with the MRI appearance of schwannomas can help aid in the differential diagnosis of soft-tissue masses, especially in unexpected locations.

Giant Schwannoma of ulnar nerve: case report

Schwannomas are the most common benign neoplasms of the peripheral nerves in the upper limbs.

Although many are asymptomatic, they can produce a mass effect, thus impinging against soft tissues or interfering with joint function.

The authors present a case report and a review of a giant Schwannoma in the ulnar nerve.

High-Resolution Ultrasound of Schwannomas of the Limbs: Analysis of 72 Cases

Schwannomas are common benign tumors that develop in peripheral nerves. High-resolution ultrasound (HRUS) is an effective imaging modality in clinics. The aim of this study was to define the value of HRUS in diagnosing schwannomas that originate from different nerves in limbs. We reviewed the ultrasound and surgical records of 72 pathologically confirmed schwannomas in the limbs of 60 patients. Results revealed that 44 (61.1%) of 72 cases, 44 (75.9%) of 58 cases and 0 (0%) of 14 cases received an overall correct pre-operative diagnosis, a correct pre-operative diagnosis in nerve trunks and a correct pre-operative diagnosis in small branches, respectively. Identification of the nerve of origin of schwannomas through HRUS likely increased confidence in diagnosing these benign tumors.

Nerve sheath tumor, benign neurogenic slow-growing solitary neurilemmoma of the left ulnar nerve: A case and review of literature

This paper represent a report of a case with ulnar nerve schwannoma (neurilemmoma), benign neurogenic slow-growing, tumors originating from Schwann cells along the course of a nerve (1) (2) (3). Schwannomas are the most common tumors of the peripheral nerves which occur in the adults (0.8–2%) (5). Usually they progress slowly and so they can remain painless swellings for a few years before other symptoms appear. Most of these lesions could be diagnosed clinically, are mobile in the longitudinal plane along the course of the involved nerve but not in the transverse plane (7). EMG, MRI, and ultrasonography are useful tools in the diagnosis. The definitive treatment of benign peripheral nerve schwannomatosis is complete enucleation of the tumor mass without damaging the intact nerve fascicles followed by confirmatory hystopathological examination (12). We present the case of a 62 years old right hand-dominant female who notice a slow increasing bulge over the inner aspect of her distal volar left forearm superior to the wrist, for a longer period of time not exactly specified; this was tracked and associated by pain, tingling and numbness over inner one and half fingers of her left hand in progress until the presentations. A diagnosis of soft-tissue tumor was presumed clinically. The other investigations were ultrasonography (US), nerve conduction studies (NCSs) such as sensory nerve action potential (SNAP) and compound muscle action potential (CMAP). In this case IRM was suggestive of a benign growth in her left ulnar nerve in the forearm region. Microsurgical techniques were used for ample enucleation of the tumor the distal volar left forearm. Subsequent histopathological examination confirmed the presumed diagnosis of a benign cellular schwannoma. At her last follow-up one month after surgery, the patient was neurological gradually improving sensory and motor function and she is highly satisfied with the results of surgery.

Neurofibroma solitario en raíz cervical C7

Los neurofibromas (NF) son tumores que se originan en la vaina de los nervios periféricos. Son poco frecuentes (un 30% aproximadamente de todos los tumores nerviosos) pero tan solo un 1% afectan al plexo cervical supraclavicular. Su desarrollo es lento e insidioso y a menudo confundido con otras patologías como son las neuropatías por compresión o las tendinopatías.

Se presenta un caso localizado en la raíz C7 de una mujer de 48 años diagnosticada y tratada durante un año de tendinopatía de «De Quervain».

Symptomatic schwannoma of the abdominal wall: A case report and review of the literature

Schwannoma is a rare, benign tumor that arises from the nerve sheath. This tumor usually involves the extremities, but can also be found in the head and neck, trunk, pelvis, retroperitoneum, mediastinum and gastrointestinal tract. In numerous cases, the tumors are asymptomatic and are identified incidentally on physical examination or imaging. Occasionally, schwannoma is symptomatic due to compression of surrounding large nerves. In the present study, a 57-year-old female presented to the surgical outpatient’s department due to a well-localized parietal pain in the left lower quadrant. The onset of the pain occurred three years prior to presentation, without apparent cause and in the absence of other symptoms. Ultrasound and a computed tomography scan revealed a small solid tumor in the anterior abdominal wall, which was dimensionally stable over time, but was not noted in a preliminary analysis by a radiologist. The lesion was surgically removed using an anterior surgical approach. Histopathology revealed the tumor to be benign schwannoma. The painful symptoms completely disappeared. To the best of our knowledge, this is the third case of an abdominal wall benign schwannoma in the medical literature, and the first symptomatic case.

Schwannomas of the upper extremity: analysis of 34 cases

BACKGROUND

Schwannomas are the most common benign tumours developing in peripheral nerves. They usually present as a slow-growing mass, sometimes associated with pain and paraesthesia. The aim of this study is to define the correct preoperative diagnosis, to review the surgical treatment employed and to evaluate short- and long-term neurological deficits.

METHODS

Thirty-four patients affected by schwannoma in the upper limbs were treated in the period 1995-2011. In 15 patients the tumour was located on the ulnar nerve, in 8 on the median nerve, in 2 on the radial nerve, in 1 on the anterior interosseous nerve, in 1 on the muscle-cutaneous nerve, and in the remaining 7 on the digital nerves. All patients were surgically treated using a microsurgical approach.

RESULTS

The enucleation of the mass was possible without fascicle lesion in 12 cases. In 22 cases resection of the indissociable fascicles was performed. Postoperative paraesthesia was present in 28 out of 34 treated patients; this clinical sign regressed in a mean period of 12 months in 27 patients.

CONCLUSIONS

When approaching a palpable mass in the upper limbs, the possibility of a peripheral nerve tumour should always be considered. It is important to look for typical signs of schwannomas, such as a positive Tinel sign and peripheral paraesthesia. Imaging assessment with magnetic resonance imaging (MRI) and ultrasonography enables the determination of where the tumour takes its origin and from which nerve. Microsurgical techniques and know-how are recommended in approaching the resection in order to respect as many nerve fibres as possible.

Imaging observations of a schwannoma of low malignant potential in the anterior abdominal wall: A case report

Neurilemmoma, also known as schwannoma, is an uncommon benign neoplasm that is most commonly found in the trunk and head and neck regions. The present study reports the case of a 67-year-old female with schwannoma localized in the anterior abdominal wall and analyzes the ultrasound and computed tomography (CT) imaging observations of the schwannoma. A dynamic time-intensity curve was also recorded in the study. A well-defined, elliptic low echo level, heterogeneous mass was observed during ultrasound examination. The CT scan revealed a solid, heterogeneous, low-density mass in the abdominal wall. Contrast-enhanced scans showed a heterogeneously enhanced mass during the arterial and venous phase. Centripetal fill-in was demonstrated and the mass was markedly, homogenously enhanced relative to the muscles during the delayed phase. Peak enhancement was observed during the venous phase and then slowly declined. However, the mass was hyperattenuated during the delayed phase. The lesion was completely excised and no evidence of recurrence has been identified during the 3 months of follow-up. The present study suggested that a diagnosis of schwannoma should be considered for certain patients with masses in the abdominal wall. Peripheral enhancement during the arterial and venous phases and homogeneous enhancement in the delayed phase are the significant imaging findings of a schwannoma.

Schwannoma in the upper limbs

Schwannomas are the commonest tumours of peripheral nerves. Despite the classical description that schwannomas are well encapsulated and can be completely enucleated during excision, a portion of them have fascicular involvement and could not be completely shelled out. A retrospective review for 8 patients was carried out over 10 years. 75% of schwannoma occurred over the distal region of upper limb (at elbow or distal to it). It occurs more in the mixed nerve instead of pure sensory or motor nerve. 50% of patients had mixed nerve involvement. Fascicular involvement was very common in schwannoma (75% of patients). Removal of the tumour with fascicles can cause functional deficit. At present, there is no method (including preoperative MRI) which can predict the occurrence of fascicular involvement; the authors therefore proposed a new system to stratify patients who may benefit from interfascicular nerve grafts. In this group of patients, the authors strongly recommend that the possibility and option of nerve graft should be discussed with patients prior to schwannoma excision, so that nerve grafting could be directly proceeded with patient consent in case there is fascicular involvement of tumour found intraoperatively.

Popliteal schwannoma mimicking baker cyst: an unusual case

Schwannoma, also known as neurilemoma, is the most common tumour of peripheral nerves. Although it is the most common tumour of peripheral nerves, it is seldom seen in adult population. We present a very rare case of schwannoma in an unusual localization. The presented case concerns a 58-year-old patient with a slowly growing popliteal mass and neuralgia for 6 months. A mass originating from a nerve or compressing a nerve was thought in the differential diagnosis. Ultrasonographic and magnetic resonance imaging revealed a heterogenous, well-defined solid mass that seems to originate from tibial nerve. Surgical excision and histopathological examination confirmed the diagnosis of schwannoma. Diagnosis of the neurilemmoma originating from lower extremity peripheral nerves may be delayed because the mass can be misdiagnosed as baker cyst or the symptoms of the patient can be thought as a result of lumber disc herniation.

Multiple schwannomas of the upper limb related exclusively to the ulnar nerve in a patient with segmental schwannomatosis

Schwannomas are benign encapsulated tumours arising from the sheaths of peripheral nerves. They present as slowly enlarging solitary lumps, which may cause neurological defects. Multiple lesions are rare, but occur in patients with neurofibromatosis type 2 or schwannomatosis. Positive outcomes have been reported for surgical excision in solitary schwannomas. However, the role of surgery in patients with multiple lesions is less clear. The risk of complications such as iatrogenic nerve injury and the high likelihood of disease recurrence mean that surgical intervention should be limited to the prevention of progressive neurological deficit. We report a case of a 45 year old male who presented with multiple enlarging masses in the upper limb and sensory deficit in the distribution of the ulnar nerve. The tumours were found to be related exclusively to the ulnar nerve during surgical exploration and excision, a rare phenomenon. The masses were diagnosed as schwannomas following histopathological analysis, allowing our patient to be diagnosed with the rare entity segmental schwannomatosis. One year post-operatively motor function was normal, but intermittent numbness still occurred. Two further asymptomatic schwannomas developed subsequently and were managed conservatively.

Peripheral neural sheath tumors (PNST)--what a radiologist should know

Peripheral neural sheath tumors (PNST) are rare and the common goal of management focuses on eliminating pain and maximizing function of the affected nerve. Therefore preoperative assessment of the specific morphological behaviour of such tumors regarding the nerves internal architecture is of utmost importance. PNSTs may affect one or more fascicles of a peripheral nerve resulting in a significant functional loss after resection and the necessity of functional reconstruction in one step. Enhancement of preoperative information should also address the biological behaviour of the tumor regarding its dignity and the resulting implications on amount of radical resection, additional treatment and prognosis. Since high-resolution techniques promise more and more detail resolution in many fields of imaging, delineation of intra- and extraneural processes as well as biological informations shall lead towards a well prepared and foreseeable image-guided treatment of PNSTs.

Magnetic resonance imaging of peripheral nerve tumours in the upper extremity

Clinical assessment and various diagnostic tools, particularly magnetic resonance imaging (MRI), of tumours of peripheral nerves are used to get an accurate diagnosis and to plan surgical intervention. Our purpose was to examine the usefulness of MRI in assessing nerve tumours in the upper extremity. Medical records of 19 patients (20 MRI examinations) with 29 histopathologically verified benign nerve tumours were examined retrospectively. In 12/20 cases MRI suggested a correct diagnosis of the type of nerve tumour. An additional 3/20 cases had an uncertain diagnosis, but nerve relations to the tumour were established. In 5/20 cases MRI gave a doubtful diagnosis with no suspicion of the tumour being located in a nerve trunk. MRI can localise and diagnose a nerve tumour in the upper extremity in 75% of cases, but it is difficult to specify the type of tumour.

Tumours of peripheral nerves in the upper extremity: a 22-year epidemiological study

Peripheral nerve tumours are uncommon. Our aims were to calculate the incidence and relative frequencies, to define sites of nerve tumours and to judge preoperative symptoms and outcomes of intervention. The results of 53 patients, with 68 tumours and histopathological diagnoses of true neoplasms, who had been operated on at the Department of Hand Surgery, Malmo, Sweden, between 1986 and 2007, were analysed. Schwannomas were the most common tumour (n=42). The incidence of schwannomas was 0.62/100 000 inhabitants/year in Malmo during that time period. The median nerve was most affected, closely followed by the ulnar and digital nerves. The preferred sites were the forearm, the thumb, and the digits. The most common preoperative symptom was pain. Loss of sensation was the most common postoperative complication. However, 33/53 patients (62%) were completely free of symptoms after excision. Patients should be provided with meticulous information preoperatively.

Schwannomas of the upper extremity: diagnosis and treatment

Schwannomas are the most common benign tumors developing in peripheral nerves. They account for 5% of all tumors in upper extremity. They usually present as a slow-growing mass, sometimes associated to pain and paresthesia. Preoperative evaluation is based on US and MRI, but final diagnosis requires histopathology. The aim of this study is to define clinical findings and MRI characteristics in identification, localization, and possible differential diagnosis of schwannomas.

Granular cell tumor: a rare tumor of the ulnar nerve

✓Granular cell tumors of the ulnar nerve are extremely rare, with only two cases previously reported in the English literature. The author presents a case of granular cell tumor of the ulnar nerve, in which the tumor was resected and the nerve was repaired with a nerve graft. The histopathological characteristics, imaging findings, and clinical data regarding these tumors are reviewed, and based on all the available evidence, a new treatment paradigm is proposed, which differs from that used in the earlier reported cases and takes into account the reported rate of tumor recurrence after incomplete resection.

Tumours of the hand

Hand tumours of soft-tissue and bony origin are frequently encountered, and clinicians must be able to distinguish typical benign entities from life-threatening or limb-threatening malignant diseases. In this Review, we present a diagnostic approach to hand tumours and describe selected cancers and their treatments. Soft-tissue tumours include ganglion cysts, giant-cell cancers and fibromas of the tendon sheath, epidermal inclusion cysts, lipomas, vascular lesions, peripheral-nerve tumours, skin cancers, and soft-tissue sarcomas. Bony tumours encompass enchondromas, aneurysmal bone cysts, osteoid osteomas, giant-cell lesions of bone, bone sarcomas, and metastases. We look at rates of recurrence and 5-year survival, and recommendations for adjunct chemotherapy and radiotherapy for malignant lesions.

Malignant tumors of the hand and wrist

Malignant tumors in the hand and wrist compose a wide variety of lesions involving skin, soft tissues, and bone. Although these lesions are found elsewhere in the body, many have unique characteristics at this anatomic location. Skin tumors predominate; the most common are squamous cell carcinomas, followed in frequency by basal cell carcinomas and malignant melanomas. Other soft-tissue malignancies are less common but may present more difficult diagnostic problems. They often appear as painless masses that sometimes have been present for months or even years and deceptively appear to be benign. A missed or delayed diagnosis of these tumors can have devastating consequences. Bone malignancies involve both primary lesions, of which chondrosarcomas are the most common, and metastatic lesions. Regardless of cell type, treatment of malignant tumors in the hand and wrist requires special considerations because of the important function of these structures. Orthopaedic surgeons should be familiar with the spectrum of these tumors, the work-up necessary to arrive at a precise diagnosis, and the treatment that will achieve the most favorable outcome.