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plasmacytoma is a neoplastic production of a single line of plasma cells , usually forming monoclonal immunoglobulin .
these tumors most often originate in the bone marrow , but extramedullary proliferation can occur in 3% of cases .
there is a male predominance at a ratio of 3:2 to females and median age of diagnosis is often in the sixth decade of life .
whereas , upper respiratory involvement is common , gastrointestinal associated solitary extramedullary plasmacytomas ( seps ) are rare , accounting for only 10% of the cases .
sep refers to a solitary nonosseous plasma cell neoplasm in the absence of any other sign of multiple myeloma , and often presents a diagnostic challenge .
we present a rare sep diagnosed by endoscopic ultrasound - guided fine needle aspiration biopsy ( eus - fna ) .
a 77-year - old female presented with lethargy , abdominal fullness , bilious vomiting , and clay - colored stool .
the patient was anemic with initial laboratory results showing total bilirubin of 4.1 mg / dl ( normal 0.4 - 1.1 mg / dl ) , direct bilirubin 2.4 mg / dl ( normal 0.1 - 0.2 mg / dl ) , aspartate transaminase ( ast ) 87 iu / l ( normal 14 - 34 iu / l ) , alanine aminotransferase ( alt ) 40 iu / l ( normal 7 - 58
iu / l ) , and alkaline phosphatase 523 iu / l ( normal 27 - 87 ) . ultrasound of the liver and computed tomography ( ct ) showed a distended gallbladder with a stone and sludge in the fundus and gallbladder wall thickening without intrahepatic or extrahepatic duct dilatation .
conservative management with intravenous ( iv ) fluids and antibiotics were initiated for acute cholecystitis with close monitoring of the liver function panel .
liver function tests ( lfts ) continued to increase despite the instituted therapy , and endoscopic ultrasound was performed .
on eus , there was mild diffuse mucosal thickening consistent with possible infiltrative disease of the gastric body without any obvious focal lesion .
there was a 1.7 cm  1.8 cm hypoechoic heterogeneous lesion noted in the porta hepatis [ figure 1 ] .
fna was performed transduodenally with a 22 gauge boston scientific needle using suction technique after the instillation of 5 ccs of normal saline and replacement of the stylet with two passes .
they were fixed in formalin , infiltrated with paraffin to solidify the cells , sliced , and stained .
immunohistochemical staining of the aspirate and the tissue biopsy showed positive staining for cd138 and monoclonal staining positive for kappa and negative for lambda [ figure 4 ] .
these results were consistent with the diagnosis of solitary extramedullary plasmacytoma of the liver and radiation therapy was initiated .
mass in the porta hepatis plasma cells in sinusoids , h&e , 40 plasma cells in sinusoids , h&e , 40 plasma cells in sinusoids , immunostain for kappa light chains , 40
plasma cell neoplasm are essentially a clonal disease of differentiated b - cells that can encompass a broad spectrum and present as asymptomatic monoclonal gammopathy of undetermined significance to plasma cell neoplasms or multiple myeloma .
five percent of patients with multiple myelomas are diagnosed with extramedullary plasmacytomas , and even less than that are diagnosed as a primary lesion .
less common sites of involvement include the gastrointestinal tract , liver , lymph nodes , testes , skin , and the central nervous system .
when the liver is affected via direct diffuse neoplastic plasma cell infiltration , or as a single or multiple space occupying lesions as plasmacytomas , it can present with symptomatic features such as extrahepatic biliary obstruction , jaundice , or ascites . in our case
, there was no evidence of diffuse infiltration of the liver on eus or ct findings .
the derangement of liver tests was attributed to a compilation of the mass with the underlying diagnosis of nonalcoholic fatty liver diseases .
when the liver is affected , the microscopic plasma cell infiltration patterns that have been described include diffuse versus nodular patterns , with diffuse including the sinusoidal , portal , and mixed types .
perez - soler et al . looked at 128 patients with multiple myeloma and found histologic findings in the liver of 16% of that population .
of that subset , roughly 50% had a microscopic finding of diffuse plasma cell infiltration of the liver , with no cases of nodular pattern detected .
plasmacytoma is a neoplastic production of a single line of plasma cells , usually forming monoclonal immunoglobulin . 
 it most often occurs in the bone marrow ; however , in 3% of the cases , solitary extramedullary plasmacytoma arises , which is a proliferation in the soft tissue , outside the bone marrow . in only 10% of the cases 
 is the gastrointestinal tract involved . a 77-year - old female presented with lethargy , abdominal fullness , bilious vomiting , and clay - colored stools . 
 the patient was anemic with initial laboratory results showing increased total and direct bilirubin with elevated transaminases . despite conservative management 
 , liver function tests ( lfts ) continued to increase . 
 on endoscopic ultrasound ( eus ) , there was mild diffuse mucosal thickening consistent with possible infiltrative disease of the gastric body without any obvious focal lesions . 
 there was a 1.7 cm  1.8 cm hypoechoic heterogeneous lesion noted in the porta hepatis and fine needle aspiration ( fna ) was performed . 
 cytology showed infiltrative plasma cells . the patient was then taken for computed tomography ( ct)-guided biopsy of the liver . 
 pathology showed liver involvement by atypical plasma cells in a nodular and sinusoidal pattern . 
 immunohistochemical staining appropriately identified the solitary extramedullary plasmacytoma . 
 plasma cell neoplasm is essentially a clonal disease of differentiated b - cells that can encompass a broad spectrum and present as asymptomatic monoclonal gammopathy of undetermined significance to plasma cell neoplasms or multiple myeloma . 
 five percent of patients with multiple myelomas are diagnosed with extramedullary plasmacytomas , and even less than that are diagnosed as a primary lesion . when the liver is affected , either as a direct diffuse neoplastic plasma cell infiltration , or as a single or multiple space occupying lesion as plasmacytomas , 
 symptomatic features include extrahepatic biliary obstruction , jaundice , or ascites . in our case , the patient was diagnosed via eus - guided fna ( eus - fna ) bringing to light an alternative method to its diagnosis .