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Paper text:
angiosarcoma is a rare neoplasm and corresponds to less than 1% among soft - tissue sarcomas .
the splenic involvement is a condition that was first described by langhans   in 1879 .
these tumors are typically present in patients older than 40 years and have no gender predilection .
some lesions are found incidentally on radiological examination ; they are more commonly diagnosed due to acute abdominal symptoms secondary to rupture .
isolated splenic metastases are rare ; only 40 cases have been reported in the literature so far [ 6 , 7 , 8 ] .
the prognosis is poor because this is an extremely aggressive tumor and 80% of the patients died by 6 months after diagnosis .
a 57-year - old woman with an extensive medical history was diagnosed with angiosarcoma of the spleen . in 1991 ,
she was diagnosed with breast ductal carcinoma ( t2pn0p ) and received a right quadrantectomy and radiotherapy ( 5,500 cgy total dose ) . in 2004 ,
she was a carrier of polycystic kidney disease type 1 , asthma , dyslipidemia and hiatal hernia . in november 2012
, she sought medical help for gastrointestinal discomfort that had become more intense a few months earlier .
a high digestive endoscopy was performed showing short barrett esophagus without dysplasia and hiatal hernia .
in addition , abdominal ultrasound was performed showing splenic complex cysts ; for better evaluation , magnetic resonance imaging ( mri ) was requested .
three months later , the mri showed a single 2-cm cystic nodule , presenting a homogeneous content .
an imaging monitoring was proposed for 6 months and gastric drugs were maintained for gastroesophageal reflux disease ( gerd ) control . on april 19 , 2013 , she went to the emergency service after 1 week of diffuse and nonstop abdominal pain , without peritonitis .
the patient underwent a diagnostic laparoscopy splenectomy and the spleen was sent to pathological analysis .
the pathologic analysis described a spleen of 200 mg weight , size 14  10  6 cm , capsule smooth , gray , with interruption areas measuring 4 cm in length .
the cut surface had a fine granular appearance of brownish color with wine - dotted areas .
microscopically , irregular nodular areas could be seen with areas of proliferation with elongated cells , arranged in bundles or around large vascular spaces with poorly defined cytoplasm and elongated nuclei and sometimes hyperstained .
the diagnosis was vascular neoplasm found by immunohistochemical evaluation , which suggests angiosarcoma of the spleen .
postoperative treatment was initiated 1 month after the procedure : 4 cycles divided into 12 infusions of paclitaxel chemotherapy and pazopanib were performed .
after 7 months of medical follow - up , the patient presented earlier gastrointestinal symptoms , and abdominal and thoracic imaging examinations showed no signs of disease .
one year and 2 months after the surgery , in the following examination , the patient complained about neck pain and cervical imaging was performed .
an mri showed secondary bone lesion with contrast enhancement in the vertebral body of c7 , with soft - tissue components projecting into the spinal canal ( size 1.7  1.5  1.1 cm ) .
three months later , the c7 lesion was resected , replaced by a titanium implant followed by 10 radiotherapy sessions ( total dose of 3,000 cgy ) . during 1 year and 1 month
however , although there was no evidence of local recurrence , the patient presented weight loss , immunodeficiency signs and hypoalbuminemia , suggesting a consumptive syndrome . the consumptive syndrome further evolved followed by impairment of the immunologic system .
angiosarcoma of the spleen is a very rare malignancy and this term is used to report a primary tumor of the spleen .
angiosarcomas correspond to less than 1% of soft - tissue sarcomas , and a smallest fraction occurs in the spleen .
the splenic cysts are usually detected on radiologic examination and surgery due to other reasons , or autopsy , but some larger cysts may present with abdominal pain and gastrointestinal symptoms .
our patient presented a prior radiologic diagnosis of a single 2-cm cystic nodule and gastrointestinal discomfort , but these symptoms were assigned to gerd .
angiosarcoma presents with no gender predilection and is most common in individuals older than 40 years .
anemia , thrombocytopenia , other coagulopathies and acute abdominal pain secondary to rupture are the most common clinical conditions in symptomatic patients [ 4 , 5 ] .
her abdominal pain was assigned to an acute expansion , probable bleeding or internal splenic lesion rupture .
our patient remained with no signs of disease for 1 year and survived for 3 years and 9 months , which is more than expected .
some case reports indicate an association with previous chemotherapy for lymphoma , radiation therapy for breast cancer and thorotrast exposure , and malignancy of the spleen . two autopsy series conducted by rane et al .   and schon et al
.   showed that the incidence of splenic neoplasms was 1.45% and that metastases to the spleen occurred in 3% of the cases , respectively [ 14 , 15 ] .
lung cancer , melanoma and breast cancer are the most primary tumor sites in spleen metastases .
although our patient underwent a prior radiotherapy treatment for breast cancer , the site of radiation was contralateral to the spleen .
in addition , radiation - induced sarcoma is usually found in children due to growth tissue . on the other hand
, the prior breast cancer could be the responsible for splenic metastases , supporting schon et al .
the definitive diagnosis could be made by pathological analysis of diagnostic splenectomy or by biopsy .
recent studies have reported success rates of splenic biopsy ranging from 63 to 89% , with complication rates ranging from 1.5 to 13% [ 16 , 17 , 18 , 19 , 20 ] .
a common complication is bleeding and the range is from 0 to 2% and it is most frequent in vascular lesions .
adjuvant chemotherapy is a controversial treatment option because there is no evidence to suggest a clinical benefit from this choice .
neuhauser et al .   reported a study of 28 patients who were treated with splenectomy , and a small part of them received adjuvant chemotherapy .
one patient survived with the disease for 8 years and another was disease free for 10 years . except for these 2 cases ,
paclitaxel use had already been reported as an adjuvant and neoadjuvant therapy by vakkalanka and milhem , suggesting that the unresectable tumor became resectable , thus improving survival with postoperative therapy .
our patient remained disease free for 1 year and 2 months after paclitaxel adjuvant chemotherapy .
thus , this case corroborates many aspects found in the literature , although other aspects challenge the known numbers and statistics data .
this means that etiology , survival and treatment of splenic angiosarcoma remain unclear and there is not yet a consensus .
consent for publication was obtained from the patient 's family . all data exposing patient identification
splenic tumors are not frequent 
 . blood vessel neoplasms are a rare category of tumors and have an extremely low incidence in the spleen . 
 this case report aims to describe a 57-year - old woman in whom a routine imaging examination had shown splenic cysts . during her follow - up , the cysts became larger and increased in number . 
 a diagnostic splenectomy was performed and its analysis showed a rare splenic angiosarcoma .