Background: Primary mesenteric tumors are rare. This study described as case series the clinical presentations and outcomes of related cases cases of giant primary mesenteric tumors seen at the Surgery Department of the Rivers State University Teaching Hospital between July 2025 and June 2026.

Materials and Methods: The clinical case notes of all patients with primary mesenteric tumors were summarized for the study.

Case Presentations: Case 1: A 56-year-old man had a central intra-abdominal mass measuring approximately 20 × 18 cm, and abdominal CT scan revealed its mesentery origin. He had complete tumor resection and the histopathological findings were spindle-cell proliferation arranged in fascicles. Case 2: A 53-year-old man had a year history of abdominal swelling and progressively worsening abdominal pain of two-month duration. CT scan of the abdomen revealed a mesenteric soft tissue mass measuring approximately 11 × 10 × 9 cm. He had complete excision of the tumor and histopathological examination revealed spindle-cell proliferation arranged in intersecting fascicles with minimal nuclear atypia and low mitotic activity. Case 3: A 53 year old female had abdominal pain and swelling of 4 months duration. Abdominal CT scan revealed a huge minimally enhancing mixed density mass measuring 19.1cm × 16.3cm, and there was hepatomegaly and splenomegaly. She had tumour excision, with splenectomy, partial gastrectomy and recontruction, and the histopathology report revealed small round blue cell tumor.

Conclusion: Three cases of mesenteric tumors were presented, out of which one had feature of local invasiveness and distant metastasis. The short-term surgical outcomes were favorable, except for the case 3 (malignant) which ended in mortality.