Gossypiboma refers to a retained foreign object that was forgotten in the body cavity during an operation. It is a rare surgical complication that most commonly occurs after intraperitoneal abdominal emergency surgical procedures, but may also occur after virtually any type of operation. Gossypiboma can be confused with neoplastic lesions and abscess. Clinical examination and radiological findings may sometimes mislead the physician. We intend to present our cases, which is thought to be a kidney tumour and bladder cancer but resulted gossypiboma which is a condition that is caused by a forgotten sponge during the operation and it can mimic the cancer. During the operation, the team must work in coordination and be careful. Unnecessary operations in such situation can significantly increase the patient's morbidity.
Keywords: Bladder cancer; Foreign body; Gossypiboma; Renal cell carcinoma.