interdigitating dendritic cell sarcoma ( idcs ) is a very rare neoplasm arising from interdigitating reticular cells , which participate in the immune response as antigen presenting cells that stimulate t lymphocytes [ 1 , 2 ] .
tumor occurrence is usually seen at t - cell rich areas of lymph nodes in the cervical , mediastinal , and axillary regions ; however , the involvement of extra - nodal sites such as the spleen , testis , urinary bladder , and pleura have also been reported [ 3 - 6 ] .
although various treatment modalities , including surgery , radiation therapy , chemotherapy , and combinations of these , have been tried , to date there is no consensus on the preferred treatment . among chemotherapeutic regimens such as chop ( cyclophosphamide , doxorubicin , vincristine , and prednisone ) , abvd ( doxorubicin , bleomycin , vinblastine , and dacarbazine ) , dhap ( dexamethasone , cisplatin , and high - dose cytarabine ) , epoch ( etoposide , prednisone , vincristine , cyclophosphamide , and doxorubicin ) , ice ( ifosfamide , carboplatin , and etoposide ) , and cisplatin / epirubicin [ 1
, 2 , 7 ] , only abvd , currently used for the treatment of hodgkin 's lymphoma , has been successful for the treatment of disseminated idcs . until now
, 2 cases of idcs have been reported in korea [ 3 , 9 ] ; 1 patient with localized idcs showed a nearly complete response to a combination of chop chemotherapy and adjuvant radiation therapy ; however , the other patient , who presented with extra - nodal involvement of the pleura , died of progressive disease after 2 cycles of chop and 1 cycle of imep ( ifosfamide , methotrexate , etoposide , and prednisolone ) .
we report the first case in korea of successful disseminated idcs treatment using only abvd chemotherapy .
a 64-year - old man presented to the primary care physician with a 1-year history of nasal congestion .
he was referred to our hospital because of abnormal physical findings in the nasal cavity .
rhinoscopic examination showed an ulcerative lesion in the inferior concha , and physical examination indicated multiple lymphadenopathies in both axillae and subcutaneous nodules in the left back . except for thrombocytosis ( 47210/l )
, laboratory tests did not show abnormal findings . after obtaining written informed consent , an excisional biopsy of the inferior concha
the lesion showed diffuse infiltration of spindle cells , large pleomorphic cells , foamy histiocytes , lymphocytes , and plasma cells ( fig .
the distinction between inflammatory conditions , such as rhinoscleroma , and neoplastic lesions , such as rosai - dorfman disease , idcs , langerhans cell histiocytosis ( lch ) , and follicular dendritic cell sarcoma ( fdcs ) , was difficult ; therefore , various immunohistochemical studies were performed . on the basis of the immunohistochemical results , i.e. , a strong positive reaction for cd68 , lysozyme , lca , and s-100 protein but a negative reaction for cd34 , cd1a , smooth muscle actin , and cd21 ( fig .
computed tomography ( ct ) scans of the chest , abdomen , and pelvis showed multiple enhancing nodules in the subcutaneous layer of the back , with lymphadenopathies in both axillae ( fig .
2a ) . a head and neck ct scan showed a soft tissue attenuating lesion in the right anterior ethmoid and nasal cavities and multiple lymphadenopathies on both sides of the neck level ii ( fig .
further to the previously reported successful treatment of idcs with abvd chemotherapy , the same abvd doses ( 25 mg / m adriamycin , 10 mg / m bleomycin , 6 mg / m vinblastine , and 375 mg / m dacarbazine ) were infused on days 1 and 15 every 4 weeks . during chemotherapy , no significant complications were observed .
after 8 cycles , ct scans of the chest , abdomen , pelvis , and neck showed complete resolution in the lymph nodes of both axillae and the subcutaneous nodules ( fig .
3b ) . ct and pet scans showed no evidence of relapse after 1 year .
dendritic cell neoplasms are rare tumors , but they are being diagnosed with increasing frequency . the world health organization ( who ) classifies dendritic cell neoplasms into 5 groups : lch , langerhans cell sarcoma , idcs , fdcs , and not specified otherwise . among the tumors arising from reticular cells ,
idcs is difficult to diagnose because of histopathologic features that are similar to other tumor types ; therefore , a high index of suspicion is required , particularly in cases with extra - nodal involvement , considering its rarity .
histological findings of an excisional biopsy specimen from the nasal concha showed diffuse infiltration of spindle - shaped cells and pleomorphic cells , in addition to foamy cells with various inflammatory cells .
tumor cells in lch are positive for cd1a and s-100 protein , whereas tumor cells in fdcs are positive for cd21 , cd35 , and clusterin . in this case , the tumor cells were positive for cd68 , lysozyme , lca , and s-100 protein but were negative for cd21 and cd1a ; these findings were consistent with the idcs immunophenotype [ 1 , 2 , 11 - 14 ]
. wide dissemination of tumors , as in this patient , has been described in most cases of idcs .
the age range in reported cases of idcs is 61 - 88 years with a mean age of 71.2 years . because of its rarity , data regarding the clinical behavior of idcs and treatment outcomes are relatively scarce . in patients with localized disease , surgical resection has been reported to be the mainstay of treatment ; however , a recurrence rate of up to 40% has been reported .
the role of chemotherapy and radiotherapy in idcs treatment has not been established . to date , chemotherapy for idcs includes the use of chemotherapeutic regimens for non - hodgkin 's disease or hodgkin 's disease ; however , results of these combination chemotherapies have been very disappointing .
the duration of remission was usually short with frequent recurrences . because of a lack of clinical data ,
high - dose chemotherapy and autologous bone marrow transplantation have also not been recommended [ 1 , 2 , 11 , 15 ] .
the abvd regimen is the only treatment known to have resulted in complete remission for disseminated idcs to date . here , we report the first case in korea of the successful treatment of disseminated idcs with 8 cycles of chemotherapy using the abvd regimen .
further studies are warranted to arrive at a consensus for the successful treatment of idcs .
however , the case reported here highlighted the efficacy of the abvd regimen , and we recommend abvd chemotherapy as a feasible treatment option for disseminated idcs in the future .
 interdigitating dendritic cell sarcoma ( idcs ) is a very rare and aggressive neoplasm that arises from antigen presenting cells . 
 idcs usually involves lymph nodes ; however , extra - nodal involvement has also been reported . 
 because a consistent standard therapy for idcs has not been established to date , we report a case of the successful treatment of disseminated idcs using abvd chemotherapy ( doxorubicin , bleomycin , vinblastine , and dacarbazine ) . 
 a 64-year - old man was diagnosed with idcs on the basis of immunohistochemical findings of a biopsy specimen of the inferior nasal concha . 
 immunohistochemical staining showed a positive reaction for cd68 , leukocyte common antigen , and s-100 protein , but a negative reaction for cd34 , cd1a , and cd21 . 
 imaging studies showed cervical and axillary lymphadenopathies , subcutaneous nodules , and a soft tissue lesion in the nasal cavity . 
 treatment with the abvd regimen resulted in complete remission after 8 cycles of chemotherapy . 
INTRODUCTION
CASE REPORT
DISCUSSION