Bladder extra-gastrointestinal stromal tumor in an elderly patient in Uganda: A case report

Introduction: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract (GI). They arise from the interstitial cells of Cajal or similar cells. Gastrointestinal stromal tumors that occur primarily outside the GI tract are termed extra-gastrointestinal stromal tumor (EGIST). These tumors are extremely rare and very few cases have been reported to date. Case Report: We report a case of a 75-year-old male who presented with a bladder mass. The patient presented with hematuria and lower urinary tract symptoms of dribbling, straining and incomplete voiding of urine. Pelvic computed tomography scan showed a well-defined homogenous mass in the urinary bladder. The tumor was partially surgically resected and histology revealed a spindle-shaped tumor that was initially reported as fibrosarcoma. However, a histology review was done and immunohistochemistry staining was positive for CKIT, CD34, and DOG-1. A diagnosis of EGIST was made. There has not been any case of EGIST reported in Uganda to the best of our knowledge. Conclusion: This case highlights the rarity of EGISTs, emphasizing the need for accurate diagnosis through immunohistochemistry and increased awareness for clinical management.