Limited utility of surveillance imaging for detection of relapse in non-Hodgkin lymphoma.

Abstract

8557 Background: Surveillance imaging with computerized tomography (CT) and positron emission tomography with CT (PET/CT) scans during follow-up after first-line therapies in patients with non-Hodgkin lymphoma (NHL) is commonly used in practice. However, most guidelines do not recommend surveillance imaging. We aimed to determine the value of routine imaging for the detection of first relapse in NHL patients in complete remission (CR) after first-line therapies. Methods: We retrospectively analyzed NHL patients referred to our center, who achieved CR after first-line therapies and subsequently relapsed. We evaluated whether the relapse was detected solely by routine CT or PET/CT or by patient-reported symptoms. Subgroup analysis was performed according to baseline histology (indolent vs. aggressive NHL). Data were also collected to determine the number of additional imaging, number of false positive scans, invasive procedures and iatrogenic complications, directly resulting from an abnormality detected on surveillance imaging. Results: Seventy-seven patients with first relapse of NHL between January 1, 2000 and December 31, 2010 were included. Majority of the relapses were detected by patient-reported symptoms as opposed to surveillance imaging (79.2% (n=61) vs. 20.8% (n=16); p<0.0001). There was no overall survival difference between the two groups (p=0.08). Patient-reported symptoms led to the detection of majority of relapses in aggressive (86.4% (n=45) vs. 13.6% (n=6); p<0.0001) and indolent NHL (69.7% (n=32) vs. 30.3% (n=10); p=0.037). There were greater number of scans done after a suspected relapse in the imaging versus symptoms group (1.94 versus 0.97; p=0.0004). Surveillance imaging led to 2 false positive scans/invasive procedures with one case of iatrogenic pneumothorax. Conclusions: Our limited retrospective analysis suggests that there is a limited role of surveillance imaging by CT or PET/CT for the detection of relapse in patients with NHL. There was no difference in survival outcome in our study between the two groups.