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soft tissue sarcomas have not been very common among the human cancers , but their incidences have been increasing slowly .
radiation , immunodeficiency , some of the drugs , some hereditary indexes and some viruses might have roles in their pathogenesis .
sarcoma in the paratesticular region would be extremely rare [ 2 , 3 ] and its treatment could not be clear .
we have presented the case of a man with more than 1.5 years history of benign scrotal mass and multiple operations .
a 55-year old man has left side inguinal hernia for 30 years but has received no treatment for it .
he was a victim of chemical warfare in 1988 , and had a coronary artery bypass graft ( cabg ) operation in 2005 . in january 2010
the patient has undergone mass excision in may 2010 , and pathology has revealed lipoma .
the right testis was normal and a multi lobulated mass measuring 452525 mm has seen in the left scrotum .
the mass has excised again in july 2011 and pathology has shown a benign spindle cell tumor .
three months later , the lesion has recurred for a second time . after reviewing pathology samples ( from the 2nd operation ) , diagnosis of low grade malignant fibrous histiocytoma has made . in a pelvic ct scan , a hypo - attenuated mass has seen in the left scrotum ( figure 1 ) .
the patient has undergone left radical orchiectomy and high ligation of spermatic cord in november 2011 .
the tumor was a 7 cm creamy yellow , lobulated soft tissue attached to left testis without necrosis or hemorrhage ( figure 2 ) .
well differentiated liposarcoma has diagnosed ( figure 4 ) . according to the american joint committee on cancer ( ajcc ) staging system for soft tissue sarcoma ( 7th ed , 2010 )
. abdomen and pelvic ct scan , chest x- ray , blood chemistry profile and serum markers ( ldh , afp and hcg ) were normal .
the patient has received 50 gy to the left scrotum and inguinal area , and then after 18 months follow up , has looks like well and disease free .
soft tissue sarcomas have not been common among the humans and have constituted only 1% of adult malignancies .
most of sarcomas have not associated with risk factors , but some environmental and genetic predispositions have proposed in a minority of patients . sarcoma in tunica albugina and vaginalis , spermatic cord and epididimis ( collectively , paratesticular region ) , scrotal skin and testicles have been very rare [ 2 , 3 ] .
patients usually have not diagnosed as sarcoma preoperatively , and have often misdiagnosed as benign lesions [ 2 , 5 , 6 ] .
soler , in a review of the literature , has believed that most paratesticular liposarcomas have presented as mass . in most reviewed reports , there were long histories of scrotal mass or treatments as benign lesion ( table 1 ) .
the patient had malignant fibrous histiocytoma of scrotum with lung metastasis and only 1 month survival . in some reports
kochman has reported local recurrence 3 months after local excision alone for well - differentiated liposarcoma of scrotal wall .
after funiculoorchidectomy , the patient was disease free for 2 years . but crespo atn has suggested that only mass excision was enough .
catton et al has reviewed 21 cases during 1958 to 1987 with paratesticular sarcoma and has suggested retroperitoneal lymph node dissection for those patients with rhabdomyosarcoma , intermediate or high grade malignant fibrous histiocytoma , or fibrosarcoma .
our patient has undergone a second operation due to local recurrence . in both operations ,
mass excision has performed but has not followed by any adjuvant therapy . in the end , radical orchiectomy has performed for him .
some authors propose hematogenic routes as important for spread in paratesticular sarcomas [ 2 , 7 ] .
reported a 63 years old man with a 2 year scrotal mass and no treatment .
their patient developed abdominal mass ; biopsy and the subsequent operation showed a 42 kg retroperitoneal myxoid liposarcoma .
schwartz has reported 6 cases with spermatic cord liposarcoma , one of whom was disease free for 23 years .
no adjuvant treatment has been considered standard for paratesticular sarcomas [ 4 , 6 , 7 ] .
some believe radiotherapy would be beneficial in recurrent or high grade liposarcoma [ 5 , 15 ] .
some authors have reported paratesticular sarcomas with a relatively prolonged disease free survival without adjuvant therapy .
the patient has not received adjuvant treatment , and was disease free for 6 years before developing local recurrence .
fujita has reported a 50-year - old man who had malignant mesenchymoma ( consisting of osteosarcoma , leiomyosarcoma , and liposarcoma ) of spermatic cord .
herein , we have reported a case of paratesticular liposarcoma who has shown good response to surgery and radiotherapy .
paratesticular liposarcoma would be so rare to have a well - studied clinical presentation , clinical course , treatment and survival .
it has seemed presenting good prognosis , but further studies have not needed to draw a conclusion .
herein , we have reported a case of paratesticular liposarcoma who has shown good response to surgery and radiotherapy .
paratesticular liposarcoma would be so rare to have a well - studied clinical presentation , clinical course , treatment and survival .
it has seemed presenting good prognosis , but further studies have not needed to draw a conclusion .
paratesticular sarcomas have happened rarely . due to the infrequency of this malignant disease and its diverse histopathologic subtypes , no standard treatment would be available . 
 multiple treatments have reported in literature with different results . 
 we have reported a 55 years old man with a 30 years history of paratesticular mass . 
 after multiple operations , radical orchiectomy has revealed liposarcoma . 
 the patient has been receiving 50 gy radiation to the scrotum and inguinal area . after 18 months 
 follow up , the patient was well and disease free . 
 he has shown good response to surgery and radiotherapy , so we have reported the disease and its clinical course .