The Pattern of Use of PET/CT Scans in the Clinical Management of Chronic Lymphocytic Leukemia.

Background: The study aimed to evaluate the utilization patterns of positron emission tomography/computed tomography (PET/CT) in chronic lymphocytic leukemia (CLL) patients and to investigate whether the results of these scans influenced treatment decisions.

Patients: and Methods: In this observational study, we analyzed patients with CLL or small lymphocytic leukemia (SLL) who underwent at least one PET/CT scan from 2007 to 2018. Patients were divided into two groups: (1) patients who had at least one fluorodeoxyglucose-avid PET/CT scan, and (2) patients who had all negative scans. PET/CT results were retrieved from patients' medical files and were revised by an expert radiologist according to visual score scale, SUVmax/SUVliver mean ratio, and the SUVmax.

Results: Of the 524 patients, 160 patients (30.5%) had PET/CT scans, and 120 patients met the inclusion criteria. A total of 219 eligible scans were analyzed; 62 of these scans (28.3%) were reported as positive, and 167 of these scans (76.3%) were performed for staging. There was a significant association between PET/CT results and change of therapy (P < .001); however, 62.9% of the positive PET/CT scans were not followed by a change of treatment. Survival time was not different between the two groups. The SUVmax/SUVliver mean ratio was negatively significantly associated with lymphocytes percent (r = -0.237, P = .042) and positively associated with lactate dehydrogenase levels (r = 0.338, P = .008) among CLL patients.

Conclusion: Despite the fact that the use of surveillance PET/CT for patients with CLL/SLL is not in the guidelines and that it is not useful for disease management, in practice the test is in frequent use in Israel.