The role of routine imaging procedures in the detection of relapse of patients with Hodgkin lymphoma and aggressive non-Hodgkin lymphoma

Abstract

Despite improved initial therapies, a subgroup of patients with aggressive non-Hodgkin (A-NHL) and Hodgkin lymphomas (HL) will relapse after first remission. The optimal follow-up strategy for the detection of relapse has not been clarified and periodic imaging is not recommended in most written guidelines. We identified 125 patients with HL and A-NHL diagnosed between January 1993 and September 2008 who relapsed at least 1 month after the end of initial therapy. We assessed whether relapse was detected based on clinical signs or periodic computed tomography (CT), [(18)F] fluorodeoxyglucose positron emission tomography (PET), or combined PET/CT and whether the mode of detection influenced the pattern and outcome of relapsed disease. Overall, most relapses (62%) were diagnosed clinically especially in A-NHL and in patients with extranodal involvement at diagnosis (p < 0.05); however, relapses of HL occurring after 2001 when PET/CT became available were more commonly detected by routine imaging (p < 0.05). Imaging-detected relapse was not associated with improved survival. While clinical exam remains the most common mode of detecting relapse, our results suggest a potential role for routine PET/CT surveillance in HL patients; however, survival does not appear to be affected by mode of detection.

Positron emission tomography/computed tomography surveillance in patients with Hodgkin lymphoma in first remission has a low positive predictive value and high costs

“…Thus, the yield of routine PET/CT surveillance was higher than expected from previous results based on non-PET imaging, but still consistent with other studies including PET or PET/CT surveillance. [19][20][21][22][23][24] The ability of PET/CT to visualize the inflammatory component of HL could at least partially explain the larger relapse fraction diagnosed by surveillance imaging in PET or PET/CT studies.…”

Positron Emission Tomographic Scans in Lymphoma: Convention and Controversy

“…However, imaging-detected relapse was not associated with improved survival. 53 An important issue related to the use of FDG-PET to screen for relapse is the high number of false-positive results 54 and the expense. 55 Furthermore, repeated PET scans increase the radiation exposure and thereby increase the risk for malignancy.…”

Positron emission tomography/computed tomography surveillance in patients with lymphoma: a fox hunt?

“…The majority of relapses (62%) were diagnosed clinically, especially, in the subgroup with aggressive NHL and in cases with extranodal disease (P<0.05). 10 Similarly, in the current issue of the Journal, El-Galaly et al report that the…”

“…7 Even with its relatively high sensitivity, the risks and benefits of routine surveillance PET/CT imaging remain controversial, mainly, because of its cost, radiation burden and the high rate of false-positive results (30-80%) 3,[8][9][10][11][12] with potential consequences of overtreatment. In this issue of the Journal, El-Galaly et al report the value of surveillance PET/CT in a retrospective cohort of 161 HL patients who achieved a complete or partial remission after first-line treatment.…”

“…While PET/CT has not been closely investigated in a surveillance setting, it has become clear that its accuracy is superior to that of CT imaging. According to results from a meta-analysis, FDG-PET predicts disease relapse with a sensitivity and specificity of 50-100% and 67-100%, respectively, for HL and 33-77% and 82-100%, respectively, for NHL, irrespective of the association of a residual mass on CT. 7 Even with its relatively high sensitivity, the risks and benefits of routine surveillance PET/CT imaging remain controversial, mainly, because of its cost, radiation burden and the high rate of false-positive results (30-80%) 3,[8][9][10][11][12] with potential consequences of overtreatment. In this issue of the Journal, El-Galaly et al report the value of surveillance PET/CT in a retrospective cohort of 161 HL patients who achieved a complete or partial remission after first-line treatment.…”