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Paper text:
angiosarcomas are poorly differentiated neoplasms composed of stands of endothelial cells and have a very narrow lumen filled with blood cells .
angiosarcomas frequently originate from the vascular wall , usually from medium and large sized veins .
they are malignant but rarely result in recurrences or metastases to lungs and lymph nodes .
angiosarcomas are commonly detected during the initial six months of life , since they usually involve the soft tissues of head and skin .
they are the most frequently found benign neoplasms of the liver in children . in adults angiosarcomas are very rare findings , being mostly described in the liver , lungs , brain and bones .
a 68-year - old patient was admitted due to loose bowel movements with traces of blood observed for a period of two weeks .
the symptoms were initially recorded by the patient 6 months prior to admission and took the form of blood in the stool .
sigmoidoscopy revealed an elevated ulcerative lesion 20 mm in diameter , located 12 cm from the anal verge along with two small polyps ( 4 mm and 8 mm ) situated 25 cm from the anal verge .
histopathology of the ulceration showed a tubular adenoma with chronic mucosa inflammation . above the splenic flexure of the transverse colon , the colonic mucosa was pink and glossy with a mesh of dilated vessels suggestive of chronic inflammation .
remaining segments of the large intestine were normal on sigmoidoscopic examination . in spite of the benign pathologic result the patient was qualified for en bloc surgical resection on these aforementioned findings . a hard
, exophytic tumor ( 5 cm  5 cm ) was found intra - operatively on the mesorectal side of the rectum .
the patient underwent resection of the upper rectum and sigmoid colon ( with formation of end - to - end anastomosis with mechanical stitches ) with regional lymphadenectomy .
no complications were noted in the postoperative period and the patient was discharged eight days after surgery .
histopathology of the tumor revealed a g3 malignant angiosarcoma with chronic inflammation of the colonic mucosa ( figs .
the surgical resection margin was negative and no metastases were found in regional lymph nodes .
fragment of intestinal wall with neoplastic infiltration of muscular layer . on the left visible intestinal mucosa with lymphoid tissue .
he , magnification 100 atypical , epithelioid cells without tendency to form blood vessel structures .
. only a few well - documented cases of angiosarcoma in this location have been reported in the literature [ 313 ] . the rare occurrence and high aggressiveness of this tumor preclude designing an optimal therapeutic approach .
surgical treatment seems to be the only effective treatment modality in cases of this malignancy with a colorectal localization .
the reported cases of angiosarcoma have documented early spread of this malignancy after surgical treatment and a short overall survival . among these cases was a 77-year - old patient reporting a history of constipation and bleeding from the lower alimentary tract , who was operated on for colorectal angiosarcoma .
numerous liver metastases were detected following the resection of the primary tumor and the patient died six months after surgery .
another reported case involved a 72-year - old patient with pulmonary metastases and colorectal angiosarcoma as the underlying primary malignancy .
he was re - operated on several months later due to massive rectal bleeding , and intraperitoneal spread was detected .
additionally , the case of a 60-year - old female patient was presented , who was also operated on due to colorectal angiosarcoma .
little is known on the long - term outcomes of adjuvant treatment ( radiotherapy and chemotherapy ) following the surgical resection of angiosarcomas .
komorowski presented a case involving a 19-year - old patient , who was diagnosed with this malignancy .
the patient was operated on and received four subsequent courses of chemotherapy and radiotherapy . at follow - up after 18 months , the patient was still alive with no signs of recurrence .
up to now , the longest postoperative survival in a colorectal angiosarcoma patient was reported by smith et al . , where a 16-year - old female patient survived 36 months after surgery .
however , in most of the above - described cases , patients diagnosed with colorectal malignancies died within one year after resection due to neoplastic spread or postsurgical complications .
in contrast , our patient survived four years after angiosarcoma resection and died due to myocardial infarction .
therefore , this is the first reported case of such long - term survival ( 48 months ) after resection of colorectal angiosarcoma .
the surgical approach implemented in our patient proved efficient , and seems the only effective modality in cases of angiosarcoma of such unusual locations as the large intestine .
further research is needed in order to verify the role of adjuvant treatment after surgical resection .
hemangioendotheliomas are poorly differentiated neoplasms built from strands of endothelial cells and have a very narrow lumen filled with blood cells . 
 hemangioendotheliomas are commonly detected during the initial six months of life , concerning mainly soft tissues and skin . 
 it is the most common bening liver cancer in children . in adults , 
 hemangioendotheliomas are very rare findings , being mostly described in the liver , lungs , brain and bones . 
 hemangioendotheliomas of the large intestine are extremely rare in adults . 
 cancer developing there is of high degree of malignancy . 
 the authors present the case of 68 year old patient in whom preoperative benign tumor with ulcers were diagnosed . 
 intraoperative macroscopic picture suggested malignant process . 
 the patient underwent anterior rectal resection with regional lymphadenectomy . the postoperative histopathological evaluation with immunohistochemical studies angiosarcoma 
 was diagnosed . 
 a four year survival free of cancer was obtained , and the patient died due to myocardial infarct . 
 literature describes the short periods of survival of patients with vascular sarcoma of the colon . 
 the most common reason for decease are metastases with massive haemorrhages . bleeding tendency results from growing kasabach - merritt syndrome . 
 it is characterized by profound thrombocytopenia and coagulopathy . 
 the presented patient is a unique example of angiosarcoma with long period of survival .