primary neuroendocrine carcinoma ( nec ) of the breast is a rare distinct clinicopathological entity , comprising 0.5 - 2% of breast carcinomas world - wide . in 2003 ,
primary nec of the breast was identified as a distinct entity by the world health organization ( who ) classification of tumors .
the who classification defines primary nec of the breast as tumors that express 50% or more of ne markers there are no previous reports of f-18 fluorodeoxyglucose ( fdg ) positron emission tomography / computed tomography ( pet / ct ) in patients with primary nec of breast with liver and bone metastasis .
here we describe a case of a 45-year - old female patient who presented with jaundice and was evaluated to have multiple liver lesions and biopsy from liver showed metastatic neuroendocrine tumor .
her chromogranin level was 886 ng / ml ( normal < 78 ng / ml ) .
she was referred for the whole body pet / ct for detection of the primary site .
pet / ct showed an intense uptake in the soft- tissue necrotic lesion in the inner quadrant of the left breast [ figure 1a and b ] with the same charecteristic feature of multiple hypodense liver lesions [ figure 1c ] .
furthermore uptake noted in a lytic lesion in the d4 vertebra [ figure 1d and e ] .
patient underwent fine - needle aspiration of the breast lesion , which confirmed neuroendocrine origin [ figure 2a and b ] .
a diagnosis of primary nec of the left breast with metastasis was made and she was treated with peptide receptor radionuclide therapy and is on follow - up now .
whole body fluorodeoxyglucose - positron emission tomography / computed tomography ( pet / ct ) maximum intensity projection image ( a ) , axial fused pet / ct showed a intense uptake in the soft - tissue lesion in the left breast ( b ) , liver lesions ( c ) and bone lesion ( d ) , axial ct showing lytic bone lesion in d4 vertebra ( e ) immunohistochemistry staining showing positive for chromogranin ( a ) and synaptophysin ( b )
primary nec of the breast is extremely rare with the first reported case in 1983 .
the most frequent reported age varies from 40 to 70 years , with a higher incidence in women greater than 60 years .
as metastatic neuroendocrine tumors of the breast are more common than that of primary neuroendocrine tumors of the breast , it is , therefore , important to differentiate primary breast neuroendocrine tumor from metastatic disease to the breast because of the differences in treatment focus .
primary nec of the breast can be diagnosed if the presence of a non - mammary primary site can be clinically ruled out or if an in situ component is histologically detected or both .
however , findings of certain studies have revealed that ne - differentiated tumors of the breast present as dense round or irregular masses with spiculated or lobular margins on the mammogram .
definitive diagnosis is made with core needle biopsy , allowing for the immunohistochemical evaluation of the specimen for the ne markers .
although the use of pet for the evaluation of ne tumors has been limited , tumors with moderate or high proliferative activity can be identified by fdg pet .
there are reports of fdg pet / ct in a case of neuroendocrine differentiated breast carcinoma with pleural metastases using indium-111 octreotide .
there are case reports of synchronous metastases to the liver and pancreas from a primary nec of the breast .
our case is the first demonstrates that 18f - fdg pet / ct provides the most significant additional information related to the accurate detection of primary nec of breast and bone metastasis and guiding treatment .
 cases of primary neuroendocrine carcinoma ( nec ) of the breast have been reported , though rare . 
 we report the case of a 45-year - old woman presented with jaundice and evaluated to have liver metastasis from neuroendocrine origin . 
 she underwent whole body positron emission tomography / computed tomography , which showed left breast lesion and bone metastasis . 
 fine - needle aspiration ( fna ) of breast revealed a nec . 
 a diagnosis of a primary nec of the breast was rendered with hepatic and bone metastasis . 
 she was treated with peptide receptor radionuclide therapy and is on follow - up . 
INTRODUCTION
CASE REPORT
DISCUSSION