the brachial plexus is frequently involved by malignant tumors of the lung apex and breast , or as a result of radiotherapy .
malignant bone tumors , such as osteosarcoma , arising from the cervical spine , clavicle or first rib may less commonly invade the plexus . however , primary tumors of the brachial plexus are rare .
a review of the literature over the last decades demonstrates a scarcity of publications on this type of tumor . with the exception of the large series of 226 brachial plexus region tumors from the louisiana state university health sciences center ( lsuhsc ) , most of the publications are case reports or small series of patients7,18,19 ) .
schwannomas and neurofibromas are the most common tumors of the brachial plexus region , and in most series in the literature neurofibroma is more prevalent6,18,21 ) .
peripheral non - neural sheath brachial plexus tumors are even rarer than tumors of neural origin and comprise a wide variety of benign and malignant tumors and tumor - like conditions14,18 ) . with regard to those tumors , preoperative evaluation and planning of proper treatment
this is a retrospective review of 22 surgically treated benign and malignant tumors of brachial plexus region to describe clinical presentation , the characteristics of brachial plexus tumor and clinical outcomes with a literature review .
twenty - one patients with consecutive 22 surgeries for primary brachial plexus tumors were enrolled between february 2002 and november 2011 were included in this study .
relevant medical history , presence of neurofibromatosis type 1 ( nf1 ) and positive details of the neurological examination were documented .
the location , size , mobility and tenderness on palpation of the tumor were assessed .
plain x - ray films and computerized tomography ( ct ) scans of tumors close to the spine were examined to find evidence of intervertebral foraminal enlargement or vertebral erosion .
magnetic resonance ( mr ) imaging was performed to document tumor location , margins , and relationship with adjacent structures .
the histopathological diagnosis of all tumors based on light microscopy was reviewed . in some instances ,
the surgical exposure depended on the site of the lesion and was initially performed under loupe magnification .
the lower lesions , involving cords and terminal nerves , required an anterior infraclavicular approach and when there was a more extensive involvement of the plexus , including its retroclavicular part , a combined anterior approach , with or without section of the clavicle , was employed . after gross identification of the tumor , the surgical microscope was brought into the field . in the beginning
, special attention was devoted to the identification , isolation and mobilization of all adjacent plexus elements , which must be dissected together with non - neural tissues away from the tumor . under higher magnification
, the proximal and distal elements directly involved and the margins of the tumor were defined . in the benign , solitary tumors , the thickened epineurium over the lesion was opened until the capsule and the mass were dissected away from adjacent nerve fascicles , in an extra capsular plane , usually as a single mass .
fascicles entering the substance of the tumor or its capsule were isolated at the proximal and distal poles of the mass .
intraoperative electrical stimulation and nerve action potential ( nap ) recording provided information about non - functioning fascicles entering and exiting the tumor . the extent of tumor removal varied from gross total resection to sub - total resection .
a more aggressive resection was substituted by a less radical level of resection whenever a significant motor impairment could result . in these cases ,
twenty - one patients with consecutive 22 surgeries for primary brachial plexus tumors were enrolled between february 2002 and november 2011 were included in this study .
relevant medical history , presence of neurofibromatosis type 1 ( nf1 ) and positive details of the neurological examination were documented .
the location , size , mobility and tenderness on palpation of the tumor were assessed .
plain x - ray films and computerized tomography ( ct ) scans of tumors close to the spine were examined to find evidence of intervertebral foraminal enlargement or vertebral erosion .
magnetic resonance ( mr ) imaging was performed to document tumor location , margins , and relationship with adjacent structures .
the histopathological diagnosis of all tumors based on light microscopy was reviewed . in some instances ,
the surgical exposure depended on the site of the lesion and was initially performed under loupe magnification .
the lower lesions , involving cords and terminal nerves , required an anterior infraclavicular approach and when there was a more extensive involvement of the plexus , including its retroclavicular part , a combined anterior approach , with or without section of the clavicle , was employed . after gross identification of the tumor , the surgical microscope was brought into the field . in the beginning , special attention was devoted to the identification , isolation and mobilization of all adjacent plexus elements , which must be dissected together with non - neural tissues away from the tumor . under higher magnification ,
the proximal and distal elements directly involved and the margins of the tumor were defined . in the benign , solitary tumors , the thickened epineurium over the lesion was opened until the capsule and the mass were dissected away from adjacent nerve fascicles , in an extra capsular plane , usually as a single mass .
fascicles entering the substance of the tumor or its capsule were isolated at the proximal and distal poles of the mass .
intraoperative electrical stimulation and nerve action potential ( nap ) recording provided information about non - functioning fascicles entering and exiting the tumor . the extent of tumor removal varied from gross total resection to sub - total resection .
a more aggressive resection was substituted by a less radical level of resection whenever a significant motor impairment could result . in these cases ,
the duration of symptoms ranged from 6 months to 10 years prior to the surgical treatment .
signs and symptoms included paresthesis and numbness ( 54.5% ) , radiating pain ( 22.7% ) , direct tenderness and pain ( 27.2% ) , palpable mass ( 77.3% ) .
twelve patients presented preoperative sensory deficit ( 54.5% ) and 9 patients among those patients accompanied with preoperative motor deficit ( 40.9% ) . on mri finding , almost all brachial plexus tumors showed well - defined mass with the long axis in line with the nerve of origin and homogeneous intermediate signal intensity ( si ) on t1-weighted sequences ( fig .
the tumors were hyperintense on t2-weighted images with inhomogeneous central low si ( the target sign ) ( fig .
3 ) . the tumors were hyperintense on t2-weighted images and showed strong enhancement following contrast administration .
schwannomas showed globoid mass with well demarcation and surrounding nerved were suspended eccentrically from the tumor .
grannular cell tumor showed multiple fusiform and lobulated enlargement of nerves , which were originated from several neural formamens .
the 22 tumors comprised a heterogeneous group of lesions in terms of their size , location and pathological characteristics .
the largest diameter of the smallest lesion and the largest lesion were 2.2 and 9.8 centimeters , respectively ( average 6.98 cm ) .
most of schwannomas appeared grossly as smooth globoid masses , which did not enlarge the nerve but are suspended eccentrically from it with a discrete attachment .
complete resection of tumor could be achieved in all cases of schwannoma because of these gross findings .
most of neurofibromas produced fusiform enlargement of the involved nerve , which made it impossible to distinguish between tumor and neural tissue .
granular cell tumor appeared fusiform and multiple lobulate enlargement of the involved nerves , which was similar to gross feature of neurofibroma .
but granular cell tumor was much harder consistency with poor demarcation between neural tissue and tumor , which impeded complete tumor resection .
twenty tumors ( 90.9% ) were benign and 2 tumors ( 9.1% ) were malignant .
benign tumors included 15 schwannomas ( 68.2% ) , 4 neurofibromas ( 18.2% ) and 1 gct ( 4.5% ) .
there were 1 malignant peripheral nerve sheath tumor ( mpnst ) and 1 malignant granular cell tumor .
gross total resection was achieved in 16 patients ( 72.7% ) , including all schwannomas , 1 neurofibroma .
subtotal resection was performed with a small residual lesion in 6 tumors ( 27.3% ) , including 3 neurofibromatosis associated with brachial plexus neurofibromas , 1 mpnst and 2 granular cell tumor in one patient . in case of granular cell tumor
, subtotal resection was performed for the first surgery , and then small residual remnant had grown three timed size big just before the revision surgery ( fig .
mean follow - up period was 13.7 months ( range 2 - 41 months ) . radiating pain and localized direct tenderness were improved immediately after surgery in 10 out of 11 patients who complained of pain at presentation , 1 patient developed new pain after surgery .
motor deficit as an initial symptom was improved in 7 out of 9 patients who complained of motor weakness at presentation .
newly developed motor deficit was improved during the follow - up period in 1 patient .
profound motor weakness was developed in the other patient with granular cell tumor after the first surgery and recovered to nearly intact status ( g4 + ) for postoperative 6 months .
the patient presented severe left shoulder pain with weakness of arm ( g2 ) . even though pain was improved , complete monoplegia was developed after revision surgery with no improvement until final follow - up .
the duration of symptoms ranged from 6 months to 10 years prior to the surgical treatment .
signs and symptoms included paresthesis and numbness ( 54.5% ) , radiating pain ( 22.7% ) , direct tenderness and pain ( 27.2% ) , palpable mass ( 77.3% ) .
twelve patients presented preoperative sensory deficit ( 54.5% ) and 9 patients among those patients accompanied with preoperative motor deficit ( 40.9% ) .
on mri finding , almost all brachial plexus tumors showed well - defined mass with the long axis in line with the nerve of origin and homogeneous intermediate signal intensity ( si ) on t1-weighted sequences ( fig .
the tumors were hyperintense on t2-weighted images with inhomogeneous central low si ( the target sign ) ( fig .
3 ) . the tumors were hyperintense on t2-weighted images and showed strong enhancement following contrast administration .
schwannomas showed globoid mass with well demarcation and surrounding nerved were suspended eccentrically from the tumor .
grannular cell tumor showed multiple fusiform and lobulated enlargement of nerves , which were originated from several neural formamens .
the 22 tumors comprised a heterogeneous group of lesions in terms of their size , location and pathological characteristics .
the largest diameter of the smallest lesion and the largest lesion were 2.2 and 9.8 centimeters , respectively ( average 6.98 cm ) .
most of schwannomas appeared grossly as smooth globoid masses , which did not enlarge the nerve but are suspended eccentrically from it with a discrete attachment .
complete resection of tumor could be achieved in all cases of schwannoma because of these gross findings .
most of neurofibromas produced fusiform enlargement of the involved nerve , which made it impossible to distinguish between tumor and neural tissue .
granular cell tumor appeared fusiform and multiple lobulate enlargement of the involved nerves , which was similar to gross feature of neurofibroma .
but granular cell tumor was much harder consistency with poor demarcation between neural tissue and tumor , which impeded complete tumor resection .
twenty tumors ( 90.9% ) were benign and 2 tumors ( 9.1% ) were malignant .
benign tumors included 15 schwannomas ( 68.2% ) , 4 neurofibromas ( 18.2% ) and 1 gct ( 4.5% ) .
there were 1 malignant peripheral nerve sheath tumor ( mpnst ) and 1 malignant granular cell tumor .
gross total resection was achieved in 16 patients ( 72.7% ) , including all schwannomas , 1 neurofibroma .
subtotal resection was performed with a small residual lesion in 6 tumors ( 27.3% ) , including 3 neurofibromatosis associated with brachial plexus neurofibromas , 1 mpnst and 2 granular cell tumor in one patient . in case of granular cell tumor
, subtotal resection was performed for the first surgery , and then small residual remnant had grown three timed size big just before the revision surgery ( fig .
mean follow - up period was 13.7 months ( range 2 - 41 months ) .
radiating pain and localized direct tenderness were improved immediately after surgery in 10 out of 11 patients who complained of pain at presentation , 1 patient developed new pain after surgery .
motor deficit as an initial symptom was improved in 7 out of 9 patients who complained of motor weakness at presentation .
newly developed motor deficit was improved during the follow - up period in 1 patient .
profound motor weakness was developed in the other patient with granular cell tumor after the first surgery and recovered to nearly intact status ( g4 + ) for postoperative 6 months .
the patient presented severe left shoulder pain with weakness of arm ( g2 ) . even though pain was improved , complete monoplegia was developed after revision surgery with no improvement until final follow - up .
many reports have been published about brachial plexus tumor since courvoisier reported the first description of the surgical excision of a brachial plexus tumor in 1886 . in 1970
dart et al.6 ) reported 27 cases of plexus tumors , 22 of which were nerve sheath tumors .
in that same year , fisher and tate10 ) reviewed the literature for all brachial plexus neoplasms reported earlier than 1970 .
otherwise , most other publications were confined to case reports or small series of nerve sheath tumors ( nsts)2,5,7,10,11,13,14,20,21,26,27 ) .
clinical presentation of brachial plexus tumor is various according to location , extension , involved neural elements and pathology .
symptoms are caused by direct nerve invasion , infiltration of surrounding tissues , or local mass effect22 ) .
the most common presenting symptom was pain ( 70% ) , followed by sensory loss ( 61% ) and weakness ( 52% ) .
about half of their patients harbored benign nsts : of these , 55% presented with a neurofibroma whereas 45% had a schwannoma .
kehoe et al.15 ) reported on 104 patients who presented with a solitary benign nst , 15 of which involved the brachial plexus .
the majority of their patients presented with the primary complaint of a palpable mass , less than half complained of local pain or paresthesia .
more recently , siqueira et al.27 ) reported on a consecutive series of 18 patients who presented with brachial plexus tumors and tumor - like conditions .
most common presenting symptom was mass ( 75% ) , pain ( 58% ) , followed by sensory change ( 41% ) . in our series , the most common presenting symptom was growing mass ( 95.4% ) , parenthesis and numbness ( 54.5% ) , sensory deficit ( 54.5% ) , motor deficit ( 40.9% ) , direct tenderness and pain ( 27.2% ) , followed by included radiating pain ( 22.7% ) . in cases of brachial plexus lesions , mr imaging is the study of choice to delineate the margins of the tumor from surrounding tissues with greatest contrast12,23 ) .
computerized tomography scanning is optimal at revealing osseous erosion around the spine or changes in neural foramina8 ) .
typical mr features of benign nsts include a well - defined oval mass with the long axis in line with the nerve of origin and homogeneous intermediate signal intensity ( si ) on t1-weighted sequences ( fig .
1 ) . the tumors are hyperintense on t2-weighted images with inhomogeneous central low si ( the target sign ) ( fig .
less commonly , schwannomas and neurofibromas may be mildly hyperintense or hypointense to muscle on t1-weighted images and show non - uniform enhancement3,29 - 31 ) .
features , including non - homogeneous contrast enhancement , an irregular , infiltrative margin and bone destruction , may be helpful to differentiate benign from malignant nsts .
schwannomas and neurofibromas are the most common tumors of the brachial plexus region , and in most series in the literature neurofibroma is more prevalent14,21 ) .
huang et al.14 ) reported that about half of their patients harbored benign nsts : of these , 55% presented with a neurofibroma whereas 45% had a schwannoma . on the contrary , siqueira et al.27 )
reported that 9 presented with a schwannoma and 1 had a neurofibroma . in our series ,
the most common benign tumors of the brachial plexus region were schwannoma and neurofibroma as same as mentioned prior , but benign tumors included 15 schwannomas ( 68.2% ) , 4 neurofibromas ( 18.2% ) and 1 granular cell tumor ( 4.5% ) .
there were 1 malignant peripheral nerve sheath tumor ( mpnst ) and 1 malignant granular cell tumor .
twenty tumors ( 90.9% ) were benign and 2 tumors ( 9.1% ) were malignant .
artico reported on cases involving 119 peripheral nerve sheath tumors ( pnsts ) , 11 of which involved the brachial plexus . in 93% of their patients with schwannomas and
81% of their patients with neurofibromas , motor function stabilized or improved postoperatively . at the 6-year follow - up
, the best surgical results were observed in the patients with schwannoma , whereas the worst results were demonstrated in those with plexiform neurofibroma2 ) .
the interest in pre - therapeutic biopsy on benign lesions is limited because the sensitivity of this procedure is moderate and the procedure could damage intact fascicles or cause haemorrhage1,14,25 ) . on the review of literature ,
postoperative outcomes were not influenced by surgical approach , but were related to grade of resection at surgery and pathological features of tumor .
gross total resection ( gtr ) can be expected for relatively small and medium size tumors , benign schwannoma , some of neurofibroma and other benign tumors , including desmoids , ganglions , cysts , epidermoids , and lipomas , and relatively good postoperative outcomes and prognosis can be expected after gtr18,19 ) . in case of large size schwannoma
tumor capsule may be encountered after skin retraction in case of large size tumor , and then further procedure can be proceeded in side of the tumor capsule . on the contrary ,
manipulation of nerve tissues may be needed after skin retraction in case of small size tumor . whereas , gtr can not be expected in case of some neurofibromas , mpnst and other malignant tumors because those tumors have diffuse infiltration to surrounding nerves and connective tissue .
subtotal resection ( str ) may be recommended for those tumors to preserve neurological function .
even when benign tumors are carefully dissected from the nerve involved under magnification , transient incomplete nerve paralysis may occur27 ) .
hosoi calculated that mpnst develops in approximately 13% of patients with von recklinghausen disease27 ) .
based on longer - term observation of a large series of patients , brasfield and das gupta reported an overall incidence of 29%7 ) .
although a small number of cases of mpnsts have been reported in patients without nf , it has long been recognized that nf ( especially nf type 1 , von recklinghausen disease ) is associated with a high incidence of mpnst .
however , post - operative radiotherapy is currently recommended by oncology consensus as part of standard treatment guidelines for these tumors , despite clear surgical margins32 ) . particularly in patients with small - sized sarcomas , surgical treatment
may promote cure , but in bigger lesions ( the majority of the cases ) , the patients should undergo adjuvant treatment after surgery .
external radiation therapy prevents local recurrence more effectively than surgery alone . despite aggressive surgery with adjuvant therapies ,
one case of our series was granular cell tumor at the first surgery and was transformed into malignant granular cell tumor at 17 months later after surgery .
granular cell tumor is benign or malignant depends histologically on evidence of increased cellularity , nuclear atypia and mitotic activity9 ) .
however , on rare occasions , a benign - appearing granular cell tumor may exhibit signs of malignancy , including invasion , local recurrence and distant metastasis before or after surgery .
local recurrence rate is 69% from 3 months to 3 years or more after initial surgery , and distant metastasis rate is 80% of patients before or after surgery9,16,17 ) .
resection of tumor is the choice of treatment in the most of benign and malignant brachial plexus tumors .
the appropriate surgical strategy is necessary in every brachial plexus tumor because postoperative outcome is influenced by grade of resection at surgery and pathological features of tumor .
appropriate intraoperative microsurgical dissection technique and electrophysiologic monitoring are essential for favorable clinical outcome . in malignant tumors ,
surgical treatment should be planed and followed by adjuvant chemotherapy or radiation therapy to alleviate presenting symptom and reduction of tumor volume .
 objectivethis is a retrospective review of 22 surgically treated benign and malignant tumors of brachial plexus region to describe clinical presentation , the characteristics of brachial plexus tumor and clinical outcomes with a literature review.methodstwenty-one patients with consecutive 22 surgeries for primary brachial plexus tumors were enrolled between february 2002 and november 2011 were included in this study . 
 the medical records of all patients were reviewed.resultseleven male and 10 female patients were enrolled . 
 mean age was 39 years . 
 three patients had brachial plexus tumor associated with neurofibromatosis ( 13.6% ) . presenting signs and symptoms included parenthesis and numbness ( 54.5% ) , radiating pain ( 22.7% ) , direct tenderness and pain ( 27.2% ) , palpable mass ( 77.3% ) . 
 twelve patients presented preoperative sensory deficit ( 54.5% ) and 9 patients presented preoperative motor deficit ( 40.9% ) . 
 twenty tumors ( 90.9% ) were benign and 2 tumors ( 9.1% ) were malignant . 
 benign tumors included 15 schwannomas ( 68.2% ) , 4 neurofibromas ( 18.2% ) and 1 granular cell tumor ( 4.5% ) . 
 there were 1 malignant peripheral nerve sheath tumor ( mpnst ) and 1 malignant granular cell tumor . 
 gross total resection was achieved in 16 patients ( 72.7% ) , including all schwannomas , 1 neurofibroma . 
 subtotal resection was performed in 6 tumors ( 27.3% ) , including 3 neurofibromatosis associated with brachial plexus neurofibromas , 1 mpnst and 2 granular cell tumor in one patient.conclusionresection of tumor is the choice of tumor in the most of benign and malignant brachial plexus tumors . 
 postoperative outcomes are related to grade of resection at surgery and pathological features of tumor . 
INTRODUCTION
MATERIALS AND METHODS
Patient population
Surgical approach
RESULTS
Demography and clinical presentation
MRI findings
Characteristic of tumor and intraoperative findings
Clinical outcomes and follow-up
DISCUSSION
CONCLUSION