The PET-CT Deception: A Postoperative Retroperitoneal Mass Resembling Recurrent Burkitt Lymphoma Following Laparoscopic Colectomy.

Burkitt lymphoma (BL) is a highly aggressive B-cell non-Hodgkin lymphoma with excellent chemosensitivity when appropriately treated. However, the interpretation of post-operative imaging findings, particularly fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT), remains challenging in distinguishing residual disease from benign post-therapeutic changes. We present the case of a 13-year-old adolescent with ileocecal BL who underwent successful chemotherapy followed by laparoscopic right hemicolectomy with intracorporeal anastomosis. Post-operative PET/CT imaging demonstrated a nodular lesion in the tumor resection bed with increased FDG uptake, raising concern for residual disease. However, adoption of active surveillance demonstrated progressive resolution of the lesion. This case highlights the importance of cautious interpretation of postoperative PET/CT findings, as hypermetabolic lesions may represent benign post-therapeutic changes rather than residual disease. In selected asymptomatic patients with favorable clinical evolution, close surveillance may be considered to avoid unnecessary invasive procedures or overtreatment.