Role of FDG-PET scan in the management of pediatric mature B cell non-Hodgkin's lymphoma. CCHE experience

Aim of work: To evaluate the sensitivity (Se), specificity (Sp), and predictive values (PV) of PET scan during management of pediatric mature B cell non-Hodgkin's lymphoma (NHL) in comparison with conventional computed tomography (CT) scan. Patients and methods: A retrospective study enrolled on pediatric NHL patients at Children Cancer Hospital Egypt (CCHE) during the period from July 2007 to the end of June 2013. Results: For 115 pediatric patients diagnosed with mature B cell NHL, 152 PET and 152 CT scans were done simultaneously. Median age was 5.7 years. They were 85 males (74%) and 30 females (26%). One hundred twenty six scans (82.9%) were done for 100 (87%) Burkitt lymphoma (BL) patients, while 26 scans (17.1%) were done for 15 (13.0%) patients with diffuse large B cell NHL (DLBC). Nineteen examination (12.5%) were done before starting chemotherapy (group 1), 107 (70.3%) at time of evaluation (group 2), and 26 (17.1%) during follow up (group C). Overall sensitivity was 91.6% for PET and 70.0% for conventional CT ( p = 0.02). Specificity was 84.1% for PET and 58.9% for CT ( p < 0.001). Positive predictive value (PPV) for PET was 50%, while was 22% for CT scan ( p < 0.001). Negative predictive value (NPV) for PET was 98%, and 92% for CT ( p = 0.01) Conclusion: PET scan is significantly more sensitive than conventional CT in the management of aggressive pediatric mature B cell NHL. PET negativity is an excellent indicator of tumor response.