in the world health organization ( who ) classification , burkitt 's lymphoma can be divided into three main clinical variants : the endemic ( also called the  african variant ) , the sporadic ( also known as non - african ) and the immunodeficiency - associated ( associated with hiv infection ) variants . the leukaemic variant of sporadic burkitt 's lymphoma , presenting with an accumulation of b blasts in the bone marrow , is quite rare . the initial manifestation of sporadic burkitt 's leukaemia in this case was masses in the maxillary sinuses , which is very rare in sporadic , as opposed to endemic , cases , and this patient was initially diagnosed with bilateral dentigerous cysts at another hospitals . we present a rare case of stage iv sporadic burkitt 's leukaemia presenting with masses and bilateral osteolysis in the maxillary sinuses . an 8-year - old boy was referred to our department in september 2014 suffering from pain and swelling of the cheeks . a diagnosis of dentigerous cysts had been made at another hospital based on computed tomography ( ct ) findings . examination of the head and neck revealed nontender , non - fluctuant , slightly compressible diffuse swelling of the cheeks . intra - oral examination revealed bilateral ill - defined diffuse swelling of the maxilla , extending from the primary molars to the second molars . vital signs were normal . a ct examination performed with contrast showed enhancing bilateral expansile masses ( right : 3.8  3.7  2.5 cm , left 3.5  3.1  2.5 cm ) within the maxillary sinuses , with osteolysis of the posterior walls ( fig . ( a ) ct image showing bilateral mass lesions within the maxillary sinuses , with osteolysis involving the posterior walls ( right : 3.8  3.7  2.5 cm , left 3.5  3.1  2.5 cm ) . ( b ) ct image after one course of chemotherapy showing partial reduction of the masses . ( a ) ct image showing bilateral mass lesions within the maxillary sinuses , with osteolysis involving the posterior walls ( right : 3.8  3.7  2.5 cm , left 3.5  3.1  2.5 cm ) . ( b ) ct image after one course of chemotherapy showing partial reduction of the masses . haematology testing showed a slightly increased white blood cell ( wbc ) count ( 11.39  10/l ) and decreased red blood cell ( rbc ) ( 3.64  10/l ) and platelet counts ( 50.0  10/l ) . iu / l ) , uric acid ( 17.9 mg / dl ) , urea nitrogen ( 30.5 mg / dl ) , creatinine ( 1.25 mg / dl ) and phosphorus ( 5.4 mg / dl ) . we referred the patient to the department of paediatric haematology and oncology of our hospital with the presumptive diagnosis of a haematopoietic tumour . bone marrow aspiration from the ilium showed a diffuse monotonous pattern of infiltration by medium - sized cells with round nuclei and basophilic cytoplasm containing vacuoles . immunophenotype analysis was negative for cd3 , tdt , mpo , mic2 and bcl2 and positive for cd10 , cd20 , cd79a , c - myc and ki67 ( fig .  2 , data not shown partially ) . chromosome banding by fluorescence in situ hybridization ( fish ) showed translocations t ( 8;14)(q24;q32 ) ( data not shown ) . positron emission tomography / ct ( pet / ct ) showed diffusely increased f - fluorodeoxyglucose uptake in bone ( fig . immunohistochemical staining , genetic analysis and imaging findings , the final diagnosis was stage iv burkitt 's leukaemia . burkitt 's leukaemia stained with haematoxylin & eosin shows infiltration of tumour cells with deeply basophilic cytoplasm , abundant lipid vacuoles in the cytoplasm , multiple small nucleoli and finely dispersed chromatin in the nuclei . immunostaining was negative for tdt and positive for cd10 , cd20 , cd79a and ki67 ( circular insets , below ) . figure  3:pet / ct image . ( a ) pet / ct image showing increased f - fluorodeoxyglucose uptake in the whole skeleton . ( b ) pet / ct image after two course of chemotherapy showing complete remission of f - fluorodeoxyglucose uptake . burkitt 's leukaemia stained with haematoxylin & eosin shows infiltration of tumour cells with deeply basophilic cytoplasm , abundant lipid vacuoles in the cytoplasm , multiple small nucleoli and finely dispersed chromatin in the nuclei . immunostaining was negative for tdt and positive for cd10 , cd20 , cd79a and ki67 ( circular insets , below ) . ( a ) pet / ct image showing increased f - fluorodeoxyglucose uptake in the whole skeleton . ( b ) pet / ct image after two course of chemotherapy showing complete remission of f - fluorodeoxyglucose uptake . the patient underwent chemotherapy based on the japanese paediatric leukaemia / lymphoma study group b - nhl03 protocol . after one course of chemotherapy , ct images showed partial reduction in the size of the masses in the maxillary sinuses ( fig . 1b ) . following two courses of chemotherapy , complete remission of abnormal uptake in the entire body , the patient is alive and under regular surveillance by the department of paediatric haematology and oncology . in the who classification , burkitt 's lymphoma accounts for 0.8% of all mature b - cell tumours . the leukaemia variant of burkitt 's lymphoma , which presents with the accumulation of b blasts in the bone marrow , is quite rare . this case showed osteolysis of the posterior wall of the maxillary sinuses , but the finding of diffuse skeletal involvement has been rarely reported   and we were unable to find other reported cases describing involvement of the maxillary sinuses . the wisdom tooth begins as a tooth germ at 4 years of age and begins to form a crown with calcification at 7 years . if lymphoma cells appear in the maxilla during this time , the crown may be covered with lymphoma , giving a dentigerous cyst - like appearance on ct as seen in fig . leukaemic involvement of the jaw is often misdiagnosed as dental infection , cysts or other tumours . however , diagnosis of this disease is often established by finding the presence of blast cells in the peripheral blood , so in those cases biopsy is not required . it is vital to make an accurate diagnosis and referral to the appropriate department for treatment .
we present a case of paediatric stage iv sporadic burkitt 's leukaemia presenting as cheek enlargement with osteolysis of the maxilla . 
 an 8-year - old boy was referred to our department with diffuse swelling of both cheeks . 
 head and neck examination revealed bilateral diffuse nontender swelling , non - fluctuant but slightly compressible . computed tomography imaging showed enhancing bilateral bulky lesions expanding the maxillary sinuses , with associated osteolysis in the posterior walls of both sinuses . 
 laboratory results included blast cells in the peripheral blood , suggesting a haematopoietic tumour . 
 we referred the patient to the department of paediatric haematology and oncology . 
 additional examinations eventually led to the diagnosis of stage iv sporadic burkitt 's leukaemia .