Abstract
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Objectives To evaluate if PET/low dose CT (ldCT) could obviate the need of a ceCT in staging and residual disease assessment in patients (pts) affected by lymphoma.
Methods We prospectively enrolled 58 pts, 35 Hodgkin Lymphoma (HL) and 23 Non Hodgkin Lymphoma (NHL), (27 women and 31 men; mean age 45.5 ± 18.5 yrs) referred to PET/ldCT and PET/ceCT for staging and 81 pts, 59 HL and 22 NHL, (33 women and 48 men; mean age 42.8 ± 17.9 yrs) referred to examinations for re-staging after treatment. In staging the diagnostic performances of PET/ldCT and of PET/ceCT were compared. In re-staging the accuracy of both examinations in residual disease detection was compared to clinical response.
Results In staging, on a site based analysis, PET/ld-CT and PET/ce-CT were discordant in 9/2088 (0,4%): 7 PET/ldCT negative and PET/ceCT positive and 2 vice versa. PET/ceCT could change the clinical stage in one single pt due to the detection of positive spleen lesion (stage III) resulted negative at PET/ldCT negative (stage II). In re-staging after treatment, sensitivity, specificity, positive and negative predictive values in detecting residual disease were 100%, 94%, 75% and 100%, respectively for both studies.
Conclusions In lymphoma patients ceCT does not add significant value to PET/ldCT both in staging and, particularly, in re-staging after treatment. While ceCT could be avoided in re-staging phase, in staging, ce-CT could be suggested for the accurate detection of abdomininal involvement