The term gossypiboma denotes a cotton foreign body retained inside the patient during surgery, a rare surgical complication. The symptoms following this entity are non-specific, such as pain, palpable mass and fever, which make clinical diagnosis difficult. The computerized tomography (CT) scan is the most useful method for diagnosis; however, sometimes the preoperative diagnosis remains uncertain even after the imaging exam. In that case, laparoscopy arises as a valuable diagnostic tool, as well as a prompt treatment option. However, when diagnosis is made years after the original surgery, the laparoscopic approach becomes harder. Our patient presented without clear symptoms, remaining asymptomatic for 34 years. The CT scan presumptive diagnosis was a gastrointestinal stromal tumour, and laparoscopy was performed providing an accurate diagnosis and treatment in the same surgical time.