intranodal schawnomas are extremely rare and just a few cases have been described before . clinical presentation comprises a symptomatic mass in several anatomical regions , but they can also be found during analysis of surgical specimens resected for other reasons . the report is based on the case of an 80-year - old patient who was underwent to right hemicolectomy for an adenocarcinoma .
an 80-year - old female patient , with personal history of intellectual development retardation , without other associated pathologies . besides she had been diagnosed with right colon adenocarcinoma , during the study of anemia .
the extension study with thoracoabdominal computed tomography scan showed no signs of local or distant disease from the primary tumor .
histopathological analysis of the surgical specimen revealed the confirmation of a low - grade adenocarcinoma , infiltrating perintestinal fat without evidence of serosa affectation ( t3 ) .
for the rest of the specimen examination , 12 perintestinal lymph nodes were observed , 10 of them with normal macroscopic and microscopic characteristics .
the two others instead showed whitish coloring and increased consistency , highly suspicious of involvement of primary adenocarcinoma , with a total size of 7 mm .
the second , however , was microscopically constituted by a spindle cell proliferation without atypia , mitosis or necrosis , displacing the normal lymphatic tissue toward periphery ( fig .
we also had positive result after immunohistochemical study for vimentin and protein s100 , and a negative one for actin , desminia , cd34 and cd117 , all of this was compatible with intranodal schwannoma ( fig .
2 ) . 
 figure 1:mesenteric node tumor microscopically constituted by a spindle cell proliferation without atypia , mitosis or necrosis , displacing the normal limphatic tissue toward periphery . 

figure 2:positive result after immunohistochemical study for vimentin and protein s100 , compatible with intranodal schwannoma .
mesenteric node tumor microscopically constituted by a spindle cell proliferation without atypia , mitosis or necrosis , displacing the normal limphatic tissue toward periphery .
positive result after immunohistochemical study for vimentin and protein s100 , compatible with intranodal schwannoma .
lymphatic affectation ( within lymph nodes ) is extremely rare and poorly described in the literature .
the lesions to beware of in the differential diagnosis are : metastatic tumor cells , including spindle cell sarcoma , spindle cell carcinoma and melanomas . among the benign lesions ,
the most important distinction must be made with the miofibroblastoma , whose characteristics include hemorrhage focuses and areas of starry arranged collagen .
while miofibroblastomas show a positivity result for actin immunohistochemistry , they do not do it for s100 protein , whose positivity is strongly linked to the schwannomas . in our case ,
it was reported just one case before by piana , of mesenteric lymph node affectation by schawnnoma in a piece of colonic resection .
remaining reports describe tumors located in retroperitoneal nodes , thoracic region , groin location or neck mass relative to growth lymph nodes [ 210 ] . in our case , as in the rest of the consulted case reports , lymph node involvement by schwannoma , could not be identified until the histopathological analysis are completed , either preoperative extension studies or macroscopic study of the surgical specimen , could suspect lymph node involvement by this tumor , because , there are not specific characteristics that could make it suspicious .
it is also noteworthy that such lymph node involvement occurred in a different one from the affected by adenocarcinoma metastasis .
intranodal schawnomas are extremely rare and < 12 cases have been previously described in the literature . the origin of those remains unknown ; therefore , as far as our review is concerned , there are not currently theories that could explain lymphatic localization . on the other hand , we have to notice that this type of diagnosis , although anecdotal by its infrequency , highlights the importance of correct microscopic evaluation of lymphatic tissue , included in the pieces of surgical , beyond their macroscopic appearance , because it has not only diagnostic importance , as in our case , but also implications in staging and subsequent treatment if malignant lesions are present .
 abstractintranodal schawnomas are extremely rare . 
 just a few cases have been described before . 
 clinical presentation comprises not only symptomatic mass in several anatomical body parts , but also , they can be found during analysis of surgical specimens resected for other reasons . the report is based on the case of an 80-year - old patient who underwent to right hemicolectomy for an adenocarcinoma . 
 the histopathologic analysis revealed one mesenteric intranodal schwannoma in the surgical specimen . 
 the diagnosis was confirmed by immunohistochemistry with positive result for vimentin and s100 protein . 
 less than 12 cases have been reported in the literature before . 
 the findings pointed out our patient as , one of these few reported with such diagnosis . 
INTRODUCTION
CASE REPORT
DISCUSSION