Background Leiomyosarcoma (LMS) of the colon is an unbelievably rare and highly invasive tumor arising from the muscularis propria of the gastrointestinal tract. After the introduction of the oncogenic role of KIT by immunohistochemistry (IHC), the reported cases of gastrointestinal leiomyosarcoma were limited. True LMS of the colon is such a rare disorder that there isn't enough description of its nature. The classical colon LMS presents with a vast majority of non-specific symptoms including

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... ild abdominal pain, fresh/obscure rectal bleeding, and weight loss. Case presentation: we experienced two extremely rare cases of colonic LMS. First patient was a 48-year-old man referred to our surgical outpatient clinic with mild intermittent abdominal pain and occasional rectal bleeding. After the initial investigation patient underwent colonoscopy that was suggestive of a large polypoid mass in 15 centimeters from the anal verge. Histopathology and Subsequent immunohistochemistry were in favor of LMS of sigmoid colon, and he underwent Laparoscopic anterior resection. The second patient was a 49-year-old man with 3-month history of fatigue, melena, and unintentional weight loss. Colonoscopy revealed a large circumferential mass in sigmoid colon 40 cm from the anal verge with the diagnosis of LMS. He underwent Laparoscopic left hemicolectomy. Conclusion: Herein, we reported two rare cases of primary leiomyosarcoma of sigmoid colon treated with laparoscopic surgery. The tumors were surgically removed via laparoscopic approach. Overall, colonic LMS is a highly invasive neoplasm with poor oncologic outcome.