Researchers find low-dose PET/CT best imaging method for lymphoma

Low-dose PET/CT demonstrates the best sensitivity and specificity for initial staging of lymphoma, according to a study presented on Thursday at the RSNA meeting.

Dr. Immaculada Pinilla Fernandez, from the University Hospital La Paz in Madrid, Spain, and colleagues prospectively studied 108 consecutive patients with biopsy-proven non-Hodgkin's lymphoma as well as Hodgkin's lymphoma. The patients underwent initial staging with F-18 FDG-PET/CT that included a low-dose CT and a PET study followed by a full-dose, contrast-enhanced CT.

Low-dose PET/CT correctly classified lymphoma stage in 77.5% of patients, while PET correctly classified 65.6% and contrast-enhanced CT identified 63%. The researchers found the sensitivity and specificity of low-dose PET/CT to be 94.8% and 90.5%, respectively. The positive and negative predictive values were 93% and 92%. PET sensitivity and specificity was 90% and 86%. Sensitivity and specificity for CT was 88% and 90%.

Since low-dose PET/CT achieved the best sensitivity and specificity, radiation dose could be reduced and use of intravenous iodinated contrast material could be avoided in patients with lymphoma, Fernandez said.