Chicago, IL—Routine surveillance imaging of asymptomatic patients in first remission after treatment for diffuse large B-cell lymphoma offers little clinical benefit at substantial cost, according to Scott F. Huntington, MD, of Abramson Cancer Center, University of Pennsylvania, Philadelphia, and colleagues. Strategies utilizing 2 years of routine computed tomography (CT) or positron emission tomography (PET)/CT scans were associated with minimal survival benefit compared with follow-up without routine imaging.
“Surveillance imaging limited to 4 scans over 2 years is associated with significant aggregate costs,” noted Dr Huntington at the 2014 American Society of Clinical Oncology meeting.
The goal of routine surveillance imaging is the detection of early relapse, but “there’s increasing data showing that the majority of patients who have diffuse large B-cell lymphoma who relapse will be symptomatic. So, the utility of imaging is questioned,” he said.
Dr Huntington and colleagues created a decision analytic Markov model and compared 3 surveillance strategies in cohorts of 55-year-old patients. The baseline model was biased to favor imaging strategies by associating asymptomatic imaging-detected relapses with improved clinical outcome, said Dr Huntington. Quality-adjusted utility, lifetime costs, and incremental cost-effectiveness ratios were calculated for each follow-up strategy.
“One trial found that patients with image-detected disease were more likely to have lower IPI [International Prognostic Index] scores, so they were basically having more favorable outcomes posttransplant,” he pointed out. “The data from that trial was used to bias toward imaging.”
The benefit of imaging-based follow-up remained small after quality-of-life adjustments. The costs associated with imaging-based surveillance strategies are considerable, and incremental cost-effectiveness ratios were $202,300 per quality-adjusted life-year (QALY) for CT strategies and $312,600 per QALY for PET/CT strategies. Incremental cost-effectiveness ratios for imaging strategies remained at >$100,000 per QALY or were dominated by routine follow-up in multiway sensitivity analyses over clinically relevant ranges.
“The question is if routine surveillance imaging or serial surveillance imaging should be used, and there are providers who suggest against surveillance imaging,” Dr Huntington noted. “Certainly you want to see patients routinely, every 3 to 6 months, and perform a close history and physical exam, because that is actually the majority of relapse—the patient is symptomatic. The patient may have changing symptoms or recurrent night sweats, and we may see new physical exam findings and new laboratory findings.”
He added that, “Usually, routine surveillance imaging is not picking up those relapses. Even in the best-case scenario for the utility of imaging, it’s still not likely to be cost-effective.”