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adrenocortical carcinoma ( acc ) is a rare neoplasm with an incidence of about one case per million population .
they have a bimodal peak ; the first one is in the fourth and fifth decades of life and the second one in the first decade . about 60% are functional tumors that secrete hormones and present with clinical features like cushing 's syndrome due to cortisone , virilizing tumor due to androgens , or feminizing tumor due to estrogens .
virilization is more frequently seen and has a better prognosis after complete resection than in adults .
recurrence , even after seemingly complete resection , is common , occurring in 23% to 85% of patients .
mri of the abdomen showed a right supra renal mass of mixed intensity measuring 6.55.33.5 cm causing minimal indentation over upper pole of the kidney .
biochemically plasma cortisol and testosterone were elevated . per operatively as there were adhesions to the kidney , the entire tumor was not removed .
microscopy revealed a tumor composed of polygonal cells arranged in solid sheets along with thick trabeculae patterns and delicate sinusoids [ figure 1 ] .
tumor giant cells , confluent areas of necrosis and foci of vascular invasion were also seen .
tumor cells arranged in thick trabecular patterns ( h and e , 400 ) a 22-year - old mentally retarded female with short stature came with a complaint of abdominal pain and lump and three episodes of seizures 2 months ago . on examination , she had cushingoid features such as central obesity , hoarseness , hirsutism , and hypertension [ figure 2 ] .
biochemical parameters estradiol , t3 , t4 , tsh , fsh and 24 hr urinary metanephrine were within normal limits . testosterone and serum cortisol were elevated .
case 2 patient showing cushingoid features and hirsutism on abdominal sonography a large exophytic mass of 98 cm from upper lobe of right kidney was identified , right adrenal could not be identified separately .
per operatively the tumor was adherent to the inferior surface of liver , kidney , and inferior venacava .
we received a grayish brown mass weighing 356 g and measuring 12.56.55.5 cm that was partly circumscribed and friable .
histologically , the tumor was composed of polygonal cells arranged in solid sheets and thick trabecular patterns with delicate sinusoids lined by flattened endothelial cells .
uninucleate , multinucleate tumor giant cells , atypical mitoses , necrosis , vascular and capsular invasion were seen [ figure 3 ] .
immunohistochemistry ( ihc ) study in both cases was positive for vimentin and inhibin and negative for cytokeratin and chromogranin [ figure 5 ] .
hence , the tumors were diagnosed as acc high grade , stage 3 , with cushing 's syndrome and virilization .
tumor showing vascular invasion ( h and e , 400 ) tumor cells showing bizarre nuclei ( h and e , 400 ) tumor cells showing inhibin positivity and inset shows chromogranin negativity ( 400 )
mri of the abdomen showed a right supra renal mass of mixed intensity measuring 6.55.33.5 cm causing minimal indentation over upper pole of the kidney .
biochemically plasma cortisol and testosterone were elevated . per operatively as there were adhesions to the kidney , the entire tumor was not removed .
microscopy revealed a tumor composed of polygonal cells arranged in solid sheets along with thick trabeculae patterns and delicate sinusoids [ figure 1 ] .
tumor giant cells , confluent areas of necrosis and foci of vascular invasion were also seen .
a 22-year - old mentally retarded female with short stature came with a complaint of abdominal pain and lump and three episodes of seizures 2 months ago . on examination
, she had cushingoid features such as central obesity , hoarseness , hirsutism , and hypertension [ figure 2 ] .
biochemical parameters estradiol , t3 , t4 , tsh , fsh and 24 hr urinary metanephrine were within normal limits .
case 2 patient showing cushingoid features and hirsutism on abdominal sonography a large exophytic mass of 98 cm from upper lobe of right kidney was identified , right adrenal could not be identified separately .
per operatively the tumor was adherent to the inferior surface of liver , kidney , and inferior venacava .
we received a grayish brown mass weighing 356 g and measuring 12.56.55.5 cm that was partly circumscribed and friable .
histologically , the tumor was composed of polygonal cells arranged in solid sheets and thick trabecular patterns with delicate sinusoids lined by flattened endothelial cells .
uninucleate , multinucleate tumor giant cells , atypical mitoses , necrosis , vascular and capsular invasion were seen [ figure 3 ] .
immunohistochemistry ( ihc ) study in both cases was positive for vimentin and inhibin and negative for cytokeratin and chromogranin [ figure 5 ] .
hence , the tumors were diagnosed as acc high grade , stage 3 , with cushing 's syndrome and virilization .
tumor showing vascular invasion ( h and e , 400 ) tumor cells showing bizarre nuclei ( h and e , 400 ) tumor cells showing inhibin positivity and inset shows chromogranin negativity ( 400 )
acc is a rare neoplasm with poor prognosis and with an incidence of one in one million population .
they have a bimodal peak in the fourth and fifth decades and a second one in the first decade . in children ,
the incidence is 0.3/million under 15 years of age . in southern brazil , it is 1015 times higher .
acc occurs with increased frequency in children with beckwith  wiedmann syndrome and li - fraumani syndrome . however , most of the tumors are sporadic .
the acc may be functional with a clinically pure endocrine syndrome like cushing 's or it may be a mixed syndrome as cushing 's with virilization .
the features that differentiate adenoma from carcinoma are weight of the tumor , if more than 95 g is usually malignant .
but sometimes tumors less than 50 g can metastasize and tumors over 1000 g may clinically benign . we have followed the weiss criteria [ table 1 ] for assessing the prognosis . results according to weiss criteria tumor is low grade if the mitotic figures are < 20 per hpf , high grade if the mitotic figures are > 20 per hpf .
if any three of nine criteria are present , the tumor is malignant . in this study , both cases showed more than three features , so they were diagnosed as malignant .
for staging of the tumor , we followed the tnm staging : stage 1 : tumor 5 cm or less with no spread to surrounding tissues or lymph nodes without distant metastasis .
stage 4 : distant metastasis . in this study , both cases were in stage 3 .
histologically , typical zellballen pattern , raised catecholamine levels in serum and positivity for immunohistochemical markers like chromogranin will favor a pheochromocytoma . whereas inhibin , melan - a , and calretinin positivity favor acc .
the third differential diagnosis was a renal cell carcinoma ( rcc ) which can infiltrate adrenal gland directly or metastasize to it .
presence of glands with red blood cells and abundant cytoplasmic glycogen and positivity for immunohistochemical markers such as cytokeratin and ema will favor rcc . in this study
we have excluded rcc , pheochromocytoma , and an adrenal cortical adenoma by the morphology , ihc markers , and also correlating with clinical and biochemical features .
acc is an extremely rare neoplasm and particularly if it occurs in children , it is essential to differentiate it from an adrenocortical adenoma by correlating with clinical , biochemical , imaging , and histological features , because their prognoses are different .
adrenocortical carcinoma ( acc ) is a rare neoplasm with a slight predilection for female patients . 
 we report two cases of acc . 
 the first case was of a 7-year - old girl who presented with clitoromegaly . 
 the second case was of a 22-year - old female who presented with a lump in the abdomen and features of cushing 's syndrome with virilization.the clinical , biochemical , histological features along with differential diagnosis are discussed . 
 these cases are presented because of their rarity , and also to highlight the importance of differentiating acc from an adenoma particularly in pediatric patients .