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paragangliomas are mostly localized in the adrenal medulla and they are usually pheochromocytomas , derived from the neural crest , but otherwise mesenteric paragangliomas are extremely rare tumors .
in this article we represent a 59-year - old female with an abdominal mass and pain due to mesenteric paraganglioma .
paragangliomas can occur as mesenteric tumors ; usually , preoperative accurate diagnosis is not possible with imaging methods and precise diagnosis is possible after histological evaluation .
paraganglia are a group of non - neural cells derived from the embryonic neural crest .
two types of paraganglia are well known ; chromaffin or sympathetic paraganglia , which are made of chromaffin cells and their primary function is endocrinal ; nonchromaffin or parasympathetic ganglia , which are made of glomus cells and are primarily responsible for chemoreceptor functions ( 1 ) .
paraganglia contain tissues such as the adrenal medulla , carotid and aortic bodies , paraganglia in sympathetic and parasympathetic nerves and organs of zuckerkandl .
the most common localization of paragangliomas is the adrenal medulla and they are usually pheochromocytomas .
extra - adrenal localization is observed in 5 - 10% of all paragangliomas ( 2 ) .
a 59-year - old woman was admitted to elazig training and research hospital general surgery clinic ( turkey ) with abdominal pain in may 2013 .
recently , the patient had noticed a mass in her abdomen . the patient s previous medical history included hypertension for 10 years , and she had laparoscopic cholecystectomy eight years ago and right tuba uterine excision due to ectopic tubal pregnancy 30 years ago .
her systolic and diastolic blood pressure was 160/100 mmhg and her pulse was 80/min on systemic examination .
laboratory findings included : white blood cell count of 11.58  10/l , hemoglobin of 13.6 mg / l and normal liver function . abdominal ultrasonographic imaging ( pvt-375at , toshiba xario  , toshiba medical systems , tokyo , japan ) had not resulted any pathological findings two and four months ago , yet the latest abdominal ultrasonography revealed a 42  28 mm hypoechoic smoothly marginated mass ( figure 1 ) .
color doppler ultrasonography showed a markedly hypervascular mass in the infraumbilical intra abdominal region , and the left inguinal region had a 21  13 mm necrotic lymphadenopathy .
abdominal computed tomography ( ct ) ( somatom definition as plus 128 , siemens ) revealed a solid mass , which was lobulary 42  36 mm in size .
contrast enhanced ct heterogeneously enhanced a hypervascular tumor at the pelvic mesenteric region ( figure 2 ) .
the patient underwent surgery , and a 6 cm diameter mass lying on the serosal wall of the terminal ileum originating from the small bowel mesentery was seen at the laparotomy .
the pathological examination revealed a cellular neoplasm and included a characteristic zellballen pattern ( figure 3 ) .
immunohistochemically tumor cells were positive for cd138 , s-100 ( in sustentacular cells ) , cd34 ( in vessels ) , chromogranin and synaptophysin .
group of cells were arranged with a characteristic  nested zellballen pattern and separated with fibrovascular connective tissue .
to the best of our knowledge a very small number of cases of mesenteric paraganglioma have been described in the english literature .
fujita et al reported that in total only 12 cases have been documented in the english literature .
the patient s median age is 57.5 years ; our patient was female and aged 59 years old .
on the other hand retroperitoneal paragangliomas are predominantly seen in males and the median age is 39 - 43 years .
the average size of mesenteric paragangliomas is 9.3 cm but this case had a 6 cm tumor .
this is probably because our patient was slim and thus the mass was noticed earlier ( 2 ) .
paragangliomas can be functional such as paroxysmal episodic hypertension , palpitations , headache , increased sweating due to secretion of catecholamines , yet extra - adrenal paragangliomas are generally nonfunctional as in our case ( 4 ) .
diagnosis of functional paragangliomas is easier than non - functional tumors ; analysis of plasma or urinary metanephrines is very sensitive when there is doubt about paraganglioma .
otherwise , imaginary techniques such as ultrasound ( us ) , ct , magnetic resonance imaging ( mri ) are almost equally effective for the detection of non - functional tumors .
scintigraphy or positron emission tomography ( pet ) scan can be effective for the detection of the features of masses ( 4 ) .
laparoscopy and biopsy are recommended for diagnosis , and tumor resection with laparoscopy or laparotomy is essential for treatment .
we performed laparotomy and extended bowel and mesentery resection in this case and she had no recurrence for 14 months .
we could not perform a laparoscopic operation because the tumor size was large and we had technical insufficiencies .
extra - adrenal paragangliomas are more aggressive than other paragangliomas , malignancy rates vary between 14 , 7 and 50% ( 3 ) .
histological evaluation is not enough for differentiation of benign or malignant tumors but presence of metastasis is essential for malignancy .
the recent world health organization classification indicates that mitotic counts and the ki-67 labeling index are significant for determining the presence of malignancy ( 2 ) .
we did not detect any metastasis in our case and ki-67 labeling index was low and mitosis was rare .
mesenteric paragangliomas are extremely rare tumors , and usually require differential diagnosis from gastrointestinal stromal tumors , lymphoma and leiomyoma . preoperative accurate diagnosis is important yet precise diagnosis is obtained by histological evaluation .
introduction : paragangliomas are mostly localized in the adrenal medulla and they are usually pheochromocytomas , derived from the neural crest , but otherwise mesenteric paragangliomas are extremely rare tumors.case presentation : in this article we represent a 59-year - old female with an abdominal mass and pain due to mesenteric paraganglioma.conclusions:paragangliomas can occur as mesenteric tumors ; usually , preoperative accurate diagnosis is not possible with imaging methods and precise diagnosis is possible after histological evaluation .