the name  granulosa cell tumor  ( gct ) was proposed by von werdt in 1914 . to have primarily originated retroperitoneal gct is even rarer . in medical literature in english from 1938 till today , only 12 cases have been reported . although , the histology of ovarian adult - type granulosa cell tumors ( agcts ) is well - documented , it is rarely encountered in cytological specimens and the identification of tumor cells is very difficult . here . per abdominal examination revealed a well - defined mass palpable in the left hypochondriac and lumbar regions . computerized tomography ( ct ) of the abdomen revealed a solid heterogeneous mass lesion measuring 11.2 cm  8 cm  12 cm , consistent with retroperitoneal hematoma [ figure 1a ] . ultrasonography ( usg)-guided aspiration of the mass was performed and the smears were hypercellular with small , overlapping cell clusters and cells in a microfollicular pattern [ figure 1b ] . on enquiry , she gave a history of hysterectomy with bilateral salpingo - oophorectomy 22 years ago for uterine leiomyoma . with these cytological features and the clinical history , a diagnosis of extraovarian agct was proposed . we received multiple dark brown and necrotic tissue fragments together measuring 10 cm  8 cm  3 cm . the cut section of all fragments showed gray white , yellowish , and hemorrhagic areas . ( a ) ct showing a solid heterogeneous mass in the left anterior pararenal space compressing left kidney ( b ) cytology smear showing cells in microfollicular pattern ( papanicolaou , 400 ) ( c ) cells in sheets and microfollicular pattern ( h and e , 400 ) ( d ) tumor cells showing strong positivity for inhibin ( inhibin , 400 ) histologically the neoplasm was composed of small round to oval neoplastic cells with predominantly microfollicular [ figure 1c ] , diffuse , and watered - silk patterns . immunohistochemistry ( ihc ) for inhibin and epithelial membrane antigen ( ema ) was done . the tumor was positive for inhibin [ figure 1d ] and negative for ema . with the typical histopathological features and ihc findings , a diagnosis of primary agct of retroperitoneum was confirmed . there are two subtypes : adult and juvenile , based on different clinical and histological features . agct of the ovary is oftentimes a hormonally active stromal cell neoplasm that is distinguished by its ability to express aromatase and to secrete sex steroids such as estrogen . the histogenetic origin of extraovarian agct is thought to be from the ectopic gonadal stromal tissue from the mesonephros . the cytological smears of an agct are usually highly cellular of both single cells , syncytial aggregates , and follicular pattern . the cells are monomorphic with scanty to moderate amount of pale cytoplasm and monomorphic round to oval nuclei having longitudinal grooves and granular chromatin . histologically , the tumor cells resemble normal granulosa cells with uniform , round or oval nuclei having finely granular chromatin and longitudinal nuclear grooves or folds . they show microfollicular , macrofollicular , trabecular , watered - silk , or diffuse patterns . extraovarian gct should be differentiated from other tumors such as small - cell carcinoma , undifferentiated carcinoma , carcinoids , and lymphoma . gct is positive for inhibin and calretinin and negative for ema whereas other tumors do not show positivity for inhibin and calretinin . the case of primary retroperitoneal gct is reported for its rarity after excluding previous ovarian origins and to describe its relevance to the histologic origin . due to their rarity , agcts present a diagnostic challenge for cytologic preparations . we believe that sensitive cytologic evaluation , histopathologic correlation , taking clinical history , and a positive immunohistochemical reaction with inhibin could help us in practice . surgery is the primary treatment for these tumors , however , long - term follow - up with history , clinical examination , and tumor markers are crucial for gcts , as later relapse is a common behavior for these unique tumors .
the most frequently occurring retroperitoneal tumors are those of the kidneys , adrenal glands , and the pancreas . 
 a primary retroperitoneal tumor composed of granulosa cells and developing far away from the normal location of the ovary is less frequently observed . 
 a 69-year - old female patient presented with abdominal discomfort . computerized tomography ( ct ) of the abdomen revealed a solid heterogeneous mass lesion measuring 11.2 cm  8 cm  12 cm consistent with retroperitoneal hematoma . 
 ultrasonography ( usg)-guided aspiration smears revealed cytological features suggestive of adult - type granulosa cell tumor ( agct ) . as the patient had a history of hysterectomy with bilateral salpingo - oophorectomy 22 years ago for leiomyoma , a diagnosis of extraovarian agct was made . 
 intraoperatively , the tumor was removed in piecemeal that showed yellowish areas with extensive necrosis and hemorrhage . 
 histopathological examination of the excised mass and inhibin positivity confirmed the diagnosis . 
 primary retroperitoneal extraovarian gct is a rare tumor with only 12 cases reported in medical literature in english .