Encapsulated neurilemoma (schwannoma) of the brachial plexus.Report of eleven cases

Axillary schwannoma mimicking lymph node metastasis-associated breast cancer: a case report

Background

Axillary schwannoma associated with breast cancer is an extremely rare disease, and previous reports have been limited. In this setting, there is great concern about whether a tumor in the axillary region is lymph node metastasis. Herein, we report a unique case of axillary schwannoma that mimicked lymph node metastasis associated with breast cancer.

Case presentation

A 68-year-old woman who underwent mastectomy and axillary lymph node dissection for right breast cancer over 20 years ago presented to our hospital with numbness and weakness in the right arm for 6 months. Ultrasonography, computed tomography, and magnetic resonance imaging showed a 20-mm well-circumscribed round tumor in the right axillary region. Initially, she was suspected of having lymph node metastasis-associated breast cancer, but the result of the core needle biopsy was a schwannoma. The patient underwent tumor enucleation. The patient has had no recurrence 1 year after the operation.

Conclusion

Axillary schwannomas often mimic lymph node metastasis in patients with a history of malignancy, particularly breast cancer. To select the optimal treatment, the clinicians should make as accurately as possible a diagnosis, with histopathological examinations, when examining patients with cancer who develop tumors in the axillary region.

Clinical Outcomes of Surgical Management of Primary Brachial Plexus Tumors

Introduction  This study evaluates the clinical presentation, tumor characteristics, and clinical outcomes of surgically treated benign and malignant brachial plexus tumors (BPTs).

Methods  A prospective study of patients with BPTs from June 2015 to August 2020 was conducted. All patients underwent surgical resection with microneurolysis and intraoperative electrical stimulation to preserve the functioning nerve fascicles.

Results  Fourteen patients with 15 BPTs underwent surgical resection. Mean age was 37.8 ± 12.3 years; with male to female ratio 4:10. The clinical presentations were swelling (100%), pain (84.6%), and paresthesia (76.9%). The lesions involved roots (5/15), trunk (5/15), division (1/15), and cords (4/15). Thirteen patients had benign pathology (8 schwannomas, 3 neurofibromas, 2 lipomas) and two had malignant neurofibrosarcoma. Gross total resection was achieved in all cases except a dumbbell tumor. The mean follow-up period was 24 ± 5 months. Postoperatively, all patients reported improvement in pain and paresthesia with no new sensory deficit. All patients had developed initial motor weakness (Grades 2–4); however, full power (Grade 5) was recovered by 3 to 5 months.

Conclusion  Total resection can be achieved by appropriate microneural dissection and electrophysiologic monitoring and is potentially curative with preserving function.

Brachial plexus tumor simulating an axillary metastasis from breast carcinoma

An ipsilateral axillary mass was detected on pre-operative ultrasound in a 79-year-old woman with newly diagnosed breast carcioma. The mass had sonographic features that were initially thought to represent a lymph node completely replaced by metastatic disease. Though ultrasound-guided axillary fine-needle aspiration was attempted, it could not be performed due to pain. At surgery, the mass was found to be a brachial plexus tumor.

Symptomatic small schwannoma is a risk factor for surgical complications and correlates with difficulty of enucleation

Postoperative neurological deficits of schwannomas are the complications that we want to avoid most. Predicting postoperative neurological deficits is crucial; however, the correlation between preoperative symptoms and neurological findings with postoperative neurological complications has not yet been completely clarified. Here we analyzed the risk factors for postoperative neurological complications. The study included 131 tumors from 107 patients histologically confirmed as schwannomas, which developed in the extremities and trunk without spinal cord involvement. The correlation between clinical findings and postoperative complications were statistically analyzed. One-hundred three tumors (78.6 %) had the preoperative neurological symptoms; these symptoms were detected in 93.3 % of small tumors (<4 cm(3)). We defined it as follows about the anatomical location of schwannomas. One is "central type" that normal nerve bundles widely splayed over the tumor's capsule (tumor located in the central region of the nerve). Another is "peripheral type" that easy to enucleate without neurolysis (tumor located in the peripheral region of the nerve). Static analysis showed a significant difference in the Tinel sign, numbness, and postoperative neurological deficits (p = 0.04, 0.006, p < 0.001, respectively). Twenty-one cases (16.0 %) showed new postoperative neurological symptoms, including numbness in 12 cases, dysesthesia in three cases, pain in three cases, and slight motor palsy in two cases. In statistical analysis, small tumors (<4 cm(3)) significantly correlated with Tinel sign (p < 0.001), and was marginally significant with postoperative neurological deficits (p = 0.05). Moreover, small tumors (<4 cm(3)) accompanying numbness preoperatively significantly correlated with postoperative neurological deficits (p = 0.04). Small (<4 cm(3)) tumors significantly correlated with the preoperative neurological symptoms. Those tumors accompanying numbness also significantly correlated with the difficulty of the enucleation and postoperative neurological deficits. These findings will help to predict the neurological complication.

Is surgery for brachial plexus schwannomas safe and effective?

BACKGROUND

Schwannomas rarely are found in the brachial plexus, and although they are benign, they present significant challenges to surgical treatment. To our knowledge, there are few studies investigating the surgical outcomes of patients with brachial plexus tumors.

QUESTIONS/PURPOSES

We analyzed the outcomes of 19 patients with brachial plexus schwannomas and asked: (1) How do these patients present? (2) Where are the tumors located in the brachial plexus? (3) What are the complications and neurologic results of patients after excision of the tumor?

METHODS

From February 2002 to August 2012, one orthopaedic hand surgeon treated 19 patients with schwannomas of the brachial plexus. We retrospectively reviewed the medical records and MRI data of all patients. There were 11 women and eight men, with a mean age of 50.2 years (range, 32-63 years). The tumor was located on the right side in eight patients and on the left in 11 patients. We evaluated neurologic deficits preoperatively and neurologic deficits and local recurrence of tumors postoperatively. Minimum followup was 12 months (mean, 37.2 months; range, 12-90 months).

RESULTS

The most common initial presentation was a palpable mass. The masses were located at all levels along the brachial plexus, including the root, trunk, cord, and terminal branches. The smallest mass was 1.5 × 1.5 × 0.5 cm and the largest was 11 × 10 × 6 cm. Fourteen of the 19 patients did not have any postoperative neurologic deficits. All the removed masses were proven histologically to be schwannomas. Of the five patients who had postoperative neurologic deficits, three had transient sensory deficits, one had weakness of the flexor pollicis longus and second flexor digitorum profundus, and another had weakness of the extensor pollicis longus. No recurrence was observed during the followup period.

CONCLUSIONS

Schwannomas of the brachial plexus are a potentially curable lesion with an acceptable surgical risk of injury to neurovascular structures. With precise surgical techniques, these tumors can be removed to improve symptoms with minimal morbidity.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Neural sheath tumors of the brachial plexus: a multidisciplinary team-based approach

Peripheral tumors of the brachial plexus, although rare, provide an opportunity for the plastic surgeon to coordinate a multidisciplinary team and achieve excellent outcomes. Most of the case series are reported from the neurosurgical literature. We report on the experience of the Kaiser Permanente Brachial Plexus Clinic over a recent 2-year period. A retrospective review was conducted to examine the medical records, radiographic images, operative reports, and pathologic findings of 13 consecutive patients with peripheral nerve sheath tumors of brachial plexus origin. Of the 10 patients requiring surgical exploration, 90% had significant improvement or resolution of pain, with sensory and motor recovery showing mixed results. Average follow-up consisted of 2 years with occupational therapy beginning shortly after operative intervention. Our results are similar to or better than those published in the literature. The plastic surgeon with subspecialty training can safely and successfully treat tumors of the brachial plexus by implementing a multidisciplinary approach.

Primary brachial plexus tumors: imaging, surgical, and pathological findings in 25 patients

Object

The authors report on the treatment of primary brachial plexus tumors in 25 patients at the University of California, San Francisco. They compare their findings with those obtained in similar series.

Methods

The authors reviewed the electronic and medical records, radiological images, operative reports, and pathological findings in 25 consecutive cases of primary brachial plexus tumors. Cases of metastatic lesions or adjacent neoplasms extending into and involving the brachial plexus were excluded.

At presentation patients ranged in age from 19 to 71 years (mean 47 ±15 years), and neurofibromatosis was present in eight patients (32%). Presenting signs and symptoms included palpable mass (60%), numbness/paresthesias (44%), radiating pain (44%), local pain (16%), and weakness (12%). Duration of symptoms ranged from 2 months to 10 years. Neuroimaging revealed lesions ranging widely in size (volume ~1 to >100 ml). Pathological diagnoses included schwannoma (15 [60%]), neurofibroma (five [20%]), malignant peripheral nerve sheath tumor (four [16%]), and desmoid tumor (one [4%]).

Conclusions

Primary tumors arising in the brachial plexus are rare. Careful workup, surgical technique, and attention to pathological diagnosis optimize management.

Surgical management of brachial plexus region tumors

BACKGROUND

Brachial plexus region tumors are uncommon and often present a challenge to neurosurgeons.

METHODS

Provide a brief historical overview, a description of the anatomy, and contribute information that provides management guidelines and improves surgical outcomes for tumors of the brachial plexus region. We also review different surgical approaches followed by surgical outcome from recent studies, as well as our own experience of treating 42 patients with tumors of the brachial plexus region at the University of Pennsylvania Medical Center between 1990 and 2001.

RESULTS

A thorough understanding of the anatomy, the clinical presentation, imaging techniques, and the various surgical approaches for brachial plexus tumor resection is necessary to ensure the best possible treatment outcome.

CONCLUSION

We conclude that with proper patient selection and appropriate perioperative and intraoperative management, neurologic deficits from brachial plexus tumor surgery can be minimized.

Results of neurilemoma treatment: a review of 78 cases

Between 1984 and 1994, a total of 78 patients underwent surgery for neurilemoma of the trunk or extremities. The incidence according to the involved nerve was analyzed and the follow-up results and complications after surgical treatment were reviewed. The median nerve was most frequently involved among 15 different nerves. Marginal excision was performed in 70 (90%) patients, incisional biopsy in 6 (8%), and wide excision in 2 (2%). Postoperative complications were paresthesia in 7 patients. There was no recurrence or malignant transformation until the average 47 months of follow-up. In most patients, marginal excision was sufficient to prevent local recurrence and did not impair nerve function significantly.

Fine-needle aspiration cytology of "ancient" schwannoma

The term "ancient" schwannoma was proposed for a group of neural tumors showing degenerative changes and marked nuclear atypia. Prior to the realization that the observed atypia was a regressive phenomenon, many of these lesions were erroneously diagnosed as sarcomas. Fine-needle aspiration (FNA) cytologic material from five patients is included in this study. Tissue examined histologically included four resected tumors and 18 gauge core biopsies of one tumor. Aspirates of ancient schwannoma showed many of the same features as FNA of regular schwannoma: aggregates of spindled cells with indistinct cytoplasm and elongate nuclei with blunt point ends. The feature unique to these lesions was nuclear pleomorphism, which was identified in all aspirates. Nuclear inclusions were identified in all but one case. Cystic degeneration, xanthomatous changes, and perivascular sclerosis were identified in excised lesions. Ancient schwannomas show most of the FNA features of benign schwannomas but can demonstrate marked nuclear atypia. The FNA features of ancient schwannoma are important to note because of the potential to confuse this lesion with a more serious one such as sarcoma on FNA.

Peripheral nerve schwannomas--an analysis of 16 patients

16 patients with peripheral nerve neurinomas (benign schwannomas) were operated upon in our hospital between 1990-1995. The largest tumours were found on proximal segments of peripheral nerves (brachial plexus: 15 cm, sciatic nerve: 20 cm). The average duration of symptoms was 1 1/2 years (range: 3 months-15 years). Pain or painful paraesthesias were the main complaints (13/16). Postoperatively, 9 patients were painfree while 4 improved. Similarly, neurological deficits were favourably influenced by the operation: Out of 5 patients with motor deficits 4 had complete, 1 patient had partial recovery. One out of 4 patients with sensory deficits had complete recovery, 2 remained unchanged, while 1 worsened. Two patients developed new motor and 6 patients new sensory deficits, which (in the course of time) did not disappear completely. New deficits developed predominantly in patients with large tumours or longstanding symptoms. Tumour recurrences were not seen during the follow-up period of 23 months. Our findings revealed that in the majority of cases peripheral nerve neurinomas can be excised with good results. Patients should be treated by a neurosurgeon with special expertise in peripheral nerve surgery. The patient should be thoroughly informed pre-operatively about any eventual new neurological deficits following surgery.

Thoracic outlet compression syndrome caused by a schwannoma of the C7 nerve root

This is the first report of a schwannoma originating from the C7 nerve root causing thoracic outlet compression syndrome. The patient was a 30-year-old woman with a 3-year history of numbness on the radial side of the left hand, left arm tiredness, nocturnal pain in the left forearm and pain in the left elbow, shoulder and neck. Conservative treatment and previous operations, including carpal tunnel release and first rib resection, provided no relief. A left scalenectomy was performed. During the removal of the anterior scalene muscle, a mass approximately 3 cm long and 1.5 cm in diameter was noted under the anterior scalene muscle involving the C7 nerve root. The tumour was encapsulated and covered with attenuated and stretched nerve fascicles. It was completely excised without disturbing the nerve fascicles. The clinical impression was schwannoma, which was confirmed on pathological examination.

Neural sheath tumors of major nerves

Over a 22-year period, operations were performed on 263 patients for 288 primary benign tumors of major peripheral nerves. The tumors included 85 schwannomas, 197 neurofibromas, and six plexiform neurofibromas. Total removal was achieved in 83 of the 85 schwannomas, and 76 of these patients were available for follow-up evaluation. Motor function either improved or was unchanged in 87% of these patients and 85% of those with pain in the distribution of the involved nerve had either total or partial resolution of their symptoms. Of the neurofibromas, 123 occurred in 121 patients without von Recklinghausen's disease. All tumors within this group were completely excised using a fascicular approach to the tumor. Of the 99 patients available for follow-up evaluation, 90% had either improved or unchanged motor function and 88% had partial or complete resolution of pain syndromes. Fifty-nine patients with von Recklinghausen's disease had 80 tumors removed: 74 fusiform tumors (58 of which were completely removed) and six plexiform tumors. Forty-eight of the 58 patients with gross total removal of fusiform tumors were available for follow-up evaluation, of whom 83% had improved or unchanged motor function and 74% had partial or complete resolution of pain syndromes. All six patients with plexiform tumors had progression of symptoms postoperatively. One brachial plexus schwannoma recurred and was re-excised without subsequent recurrence at the 5-year follow-up evaluation. Several incompletely excised plexiform neurofibromas have recurred with a symptomatic presentation.

Face and neck neurogenic neoplasms

Surgeons should be aware that any mass in the region of the cranial nerves, brachial plexus, cervical sympathetic plexus, or a major peripheral nerve can be of neurogenic origin. Solitary neurogenic tumors of the head and neck can simulate metastatic masses or congenital lesions. If they are resected unrecognized and/or without regard to their nerve origin, major and permanent nerve defects can unnecessarily occur. Thirty-two patients, 16 males and 16 females, ranging in age from 5 to 69 years, had 33 extracranial solitary neurogenic neoplasms resected. The nerves involved were the cervical sympathetic plexus in 7 patients, branchial plexus in 6, spinal accessory nerve in 5, vagus nerve in 4, hypoglossal nerve in 3, facial nerve in 2, and 6 other nerves in 1 patient each. The technique is to dissect out the neurilemoma without destroying the nerve sheath or nerve trunk. Despite careful dissection, the four patients with masses of the vagus nerve had permanent ipsilateral cord paralysis.

Degenerative ("ancient") changes in benign cutaneous schwannoma. A light microscopic, histochemical and immunohistochemical study

We studied the degenerative "ancient" changes in 19 cases of benign cutaneous schwannoma (BCS). Using conventional and immunohistochemical stains, we found (a) degenerative changes in 15 of 19 BCS; (b) prominent vascular abnormalities in 11 of 15 BCS; and (c) cytologic atypia in 15 of 19 BCS, without mitotic figures. We concluded that (1) degenerative, i.e., "ancient" changes are common in BCS and are qualitatively similar to those described in cellular schwannoma; (2) vascular abnormalities may be related to these degenerative changes; (3) cytologic atypia is commonly associated with "ancient" changes in BCS, but BCS is less cellular and has few if any mitotic figures as opposed to cellular schwannomas; and (4) the changes in "ancient" schwannoma do not indicate a "cellular" schwannoma.

Retroperitoneal neural sheath tumors: Cleveland Clinic experience

Retroperitoneal neural sheath tumors are a rare clinical entity with a variable and nonspecific presentation, whose accurate preoperative diagnosis often can be difficult. Since July 1984, 9 retroperitoneal neural sheath tumors, including 3 benign schwannomas, 3 malignant schwannomas and 3 neurofibromas, were evaluated at our institution. Preoperative evaluation included a computerized tomography scan in all patients and magnetic resonance imaging in 4. Magnetic resonance imaging offered better resolution and anatomical definition in certain cases. Preoperative computerized tomography-guided needle biopsy, performed in 3 patients, yielded inaccurate or inconclusive results. The 6 patients with surgically resected benign schwannomas and neurofibromas had no local recurrences and all 6 had no evidence of disease (mean followup 17.3 and 14 months, respectively). Malignant tumors, especially when associated with von Recklinghausen's disease, offered a poor prognosis. Surgical considerations include complete tumor excision with free margins of resection and proper pathological evaluation to determine biological potential.

Schwannoma of the brachial plexus with intrathoracic extension

Images

Ancient neurilemmoma (schwannoma)

A clinical and light microscopic study of 11 patients with ancient neurilemmoma is presented. Ancient neurilemmoma is a cellular form of ordinary neurilemmoma, showing nuclear polymorphism and hyperchromasia. Seven patients were female and 4 were male; their ages ranged between 37 years and 81 years, with a median of 59 years. Seven tumours were 2.5 cm or larger in the widest diameter, and had been slowly enlarging for one year or more. All tumours were solitary, encapsulated showing nuclear polymorphism and hyperchromasia without any mitotic activity. The differential diagnosis is discussed. Follow-up information available on all patients confirmed that the clinical course is benign.