extranodal nhl can occur in any visceral or non - visceral organ , but there are several predominant sites , including the stomach , small intestine , skin , and brain .
nhl in the breast or testis is relatively rare , representing 0.38%-0.7% and 1%-2% of all nhl , respectively .
these types of lymphoma are generally high - grade lymphomas with an aggressive clinical course .
the main treatment strategy for diffuse large b - cell lymphoma ( dlbcl ) with involvement of the breast is an anthracycline - containing chemotherapy with or without radiotherapy .
the role of central nervous system ( cns ) prophylaxis remains controversial despite the risk of cns relapse , due to unproven benefit . on the other hand , anthracycline - based chemotherapy combined with locoregional radiotherapy to the contralateral testis and cns prophylaxis
the 5-year overall survival rate from previous reports varies from 26% to 71% in breast lymphoma and 56%-87% in testicular lymphoma . here
we report a patient with dlbcl involving both the breast and testis who was successfully treated with complete resection of the involved testis ; immunochemotherapy with rituximab , cyclophosphamide , doxorubicin , vincristine , and prednisolone ( r - chop ) ; and prophylactic radiotherapy to the contralateral testis .
a 76-year - old man visited our hospital ( asan medical center , seoul , korea ) with a mass on his right breast first being recognized two months ago .
he had no b symptoms and an unremarkable medical history , except for hypertension . on physical examination
he had a rubbery , non - tender , mobile mass of approximately 4 cm on his right breast .
there were no other palpable lymph nodes in the axillary , neck , or inguinal area , but his right testis was slightly harder than the left testis , without a definite mass .
iu / l , and 2 microglobulin was 1.8 g / ml . screening tests for human immunodeficiency virus , hepatitis c virus , and hepatitis b virus were all negative . on mammography , a heterogeneous , dense , lobulated mass - like lesion was observed in the subareolar portion of the right breast .
the pathologic specimen from core needle biopsy revealed diffuse proliferation of large , atypical lymphoid cells ( fig .
1b ) , bcl-6 , and irf4/mum1 , but was negative for cd10 . in situ hybridization for epstein - barr virus was also negative .
based on these pathologic findings , the patient was diagnosed with dlbcl . a staging work - up including bone marrow biopsy with aspirate , positron emission tomography  computed tomography ( pet - ct ) , and abdomen and chest computed tomography ( ct ) revealed no evidence of other nodal or marrow involvement . however , the pet - ct showed increased metabolism in the right testis , with a maximum standardized uptake value of 8.4 ( fig .
pathologic examination revealed a well - defined ovoid mass ( 3.82.51.6 cm ) , which was confirmed as dlbcl ( fig .
, he was finally diagnosed with dlbcl involving both the breast and testis , with an ann arbor clinical stage of 4ea .
the patient received a total of six cycles of immunochemotherapy ( 375 mg / m rituximab on day 1 , 750 mg / m cyclophosphamide on day 1 , 50 mg / m doxorubicin on day 1 , 1.4 mg / m vincristine on day 1 , and 50 mg prednisolone bid on days 1 - 5 [ r - chop ] ) .
follow - up ct and pet - ct after four cycles and six cycles of r - chop immunochemotherapy confirmed a complete response .
after six cycles of r - chop immunochemotherapy , prophylactic radiotherapy of 25 gy with 10 fractions was administered to his left testis .
he has been followed at the outpatient clinic regularly without evidence of relapse for 17 months .
extranodal nhl of the breast is uncommon , and its occurrence in male patients is extremely rare .
table 1 provides an overview of previously reported cases of male primary breast lymphoma ( pbl ) [ 3 - 13 ] .
none of these cases presented with metastatic disease at first presentation , but three patients relapsed at other sites , including the cns , bone marrow , cervical lymph nodes , and adrenal glands .
the prognosis of pbl is somewhat variable , with the 5-year survival rate ranging from 26%-71% . according to some reports , progression to cns is relatively more common in pbl than in other nhl , ranging from 12%-27% .
recent studies , however , suggest that routine cns prophylaxis should not be given despite the high risk of cns relapse in pbl , because there is no survival benefit . in primary testicular lymphoma ( ptl ) ,
previous studies report a continuous pattern of relapse , even at 10 - 14 years after initial therapy .
similar to pbl , common sites of relapse include extranodal sites such as the cns and contralateral testis .
the risk of cns relapse is reported to be 20% and 35% at 5 and 10 years , respectively .
although bilateral involvement is uncommon at diagnosis , up to 35% of ptl patients develop contralateral testicular involvement later in their clinical course , which provides a rationale for prophylactic radiotherapy to the contralateral testis .
anthracycline - containing chemotherapy ( i.e. , chop ) is considered the standard treatment option for early - stage dlbcl .
a number of cases benefitted from radiotherapy upon relapse on the contralateral side , which improved overall and progression - free survival in ptl .
the role of additional radiotherapy to the involved side of breast , however , is yet to be determined , although it did show positive effects on progression - free survival and the risk of ipsilateral locoregional progression . here , we present the first reported case of dlbcl with simultaneous breast and testicular involvement , without any nodal presentation .
the patient received immunochemotherapy ( r - chop ) and prophylactic radiotherapy to the contralateral testis because of the high relapse rate of testicular lymphoma . in summary ,
dlbcl involving both the breast and testis was successfully treated with multimodal strategies and showed a favorable response without evidence of recurrence .
 here we report a case of a 76-year - old man with diffuse large b - cell lymphoma ( dlbcl ) with simultaneous involvement of the right breast and left testicle . 
 the patient underwent complete resection of the involved testis , followed by immunochemotherapy with rituximab , cyclophosphamide , doxorubicin , vincristine , and prednisolone ( r - chop ) and prophylactic radiotherapy to the contralateral testis . following this multimodal therapy 
 , he achieved a complete response . 
 this is a rare case of dlbcl involving both the breast and the testis in a male patient . 