Leiomyosarcoma of Colon Presented as Retroperitoneal Mass: A Rare Case Report

Introduction: Retroperitoneal tumors are lesions with diverse pathological subtypes that originate from the retroperitoneal space. About forty percent of these tumors are benign. These lesions are often surrounded and associated with vital abdominal blood vessels; therefore, a complete surgical resection is difficult. Presentation of the case: Here we are presenting a 42-year-old female presented with abdominal lump from last two monthswith persistent abdominal pain from one month. The computed tomography and ultrasound scan confirmed the presence of a solid retroperitoneal tumor. She underwent surgical exploration and histology confirmed that the tumor composed of spindle shaped cells disposed in intersecting fascicles, whirling and storiform pattern. The tumor cells are oval to spindle shaped with blunt ended nuclei, dispersed chromatin and moderate amount of cytoplasm. On immunohistochemical staining, tumor cells were positive for vimentin. The patient was followed up for two years, with no evidence of tumor recurrence. No standardized guidelines have been established for its treatment because too small a number of cases have been reported, but surgical resection was considered the treatment of choice. In summary, we report a unique case who developed leiomyosarcoma of colon presented as retroperitoneal mass. Conclusion: In this case report we described this rare occurrence of leiomyosarcoma of colon and highlight the diagnostic difficulties such cases can pose along with a review of relevant literature.