Role of FDG PET-CT in restaging of Hodgkin's lymphoma

Objectives The present study was aimed to determine the role of FDG PET-CT in restaging Hodgkin’s disease (HD) after primary treatment.

Methods Forty six patients of HD, who were treated with chemotherapy and/or radiotherapy, were included in this study. There were 26 male and 20 female patients with mean age of 38.3 and range of 10-79 years. All patients underwent PET-CT scans 4-6 weeks after completion of chemotherapy. All patients had follow up PET-CT scan 6-12 months after previous PET-CT scan. The results of the PET-CT were compared with histopathology and/clinical follow up with PET/CT. Sensitivity, specificity, PPV, NPV and accuracy were calculated with the help of reference standard.

Results Of the 46 patients, 21 showed positive results and 25 showed negative results on PET-CT scan. Based on histopathology and/clinical follow up with PET/CT, there were 17 true positive, 23 true negative, 4 false positive and 2 false negative scans. PET-CT found to have a sensitivity of 89% and specificity of 85% in restaging HD patients. The PPV, NPV and accuracy were 81%, 92% and 87%, respectively.

Conclusions PET-CT is a highly sensitive and specific technique in restaging Hodgkin’s disease (HD) after primary treatment. However, inflammatory and granulomatous conditions can lead to false positive and microscopic disease can lead to false negative results.