B-cell lymphoma (DLBCL) do not experience a relapse after first complete remission (CR), and the risk of relapse drops dramatically after five years in CR. Follow-up programs routinely include imaging to detect early relapse but, according to a new report published in the Journal of Clinical Oncology, this serial routine imaging does not benefit patients.
“Although it is rational to believe that preclinical relapse detection can improve patient outcome as a result of [treating] lower tumor burden, the actual value of routine imaging for DLBCL is controversial, and there are no data to clearly support its use,” the authors of the study, led by Tarec Christoffer El-Galaly, MD, from the department of hematology at Aalborg University Hospital in Denmark, wrote. Unnecessary imaging, they added, can lead to radiation-related cancers, extra medical costs, and increased patient anxiety and concern.
Dr. El-Galaly and colleagues conducted an observational, population-based study comparing the survival of Danish and Swedish patients with DLBCL who underwent different imaging protocols. These two countries have similar health-care systems, the authors noted, though their practices for routine imaging in this patient population are completely different.
Standard of care for DLBCL patients in both countries includes symptom assessment, clinical examination, and blood tests at two- to four-month intervals for the first two years starting at the time of CR, followed by every six months for three years. In Denmark, routine imaging with computed tomography (CT) scans of the neck, thorax, and abdomen is also encouraged every six months for two years; in Sweden, however, routine imaging is discouraged in the national guidelines.
A total of 1,221 patients were selected from the Danish Lymphoma Group Registry (n=525) and Swedish Lymphoma Registry (n=696). All patients were18 to 65 years old, had been newly diagnosed with DLBCL between 2007 and 2012, and had reached CR after R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone)/CHOEP (cyclophosphamide, doxorubicin, etoposide, vincristine, and prednisone) therapy.
Over a median follow-up of 51 months, 69 percent of relapses occurred in the first 24 months post-CR, 15 percent occurred within 24 to 36 months, and 16 percent occurred after 36 or more months. The three-year overall survival for all patients was 92 percent, with no difference between Danish and Swedish patients (92% vs. 91%; p=0.7).
The following patient characteristics were associated with worse overall survival post-CR: age over 60 years, elevated lactate dehydrogenase, presence of B symptoms at diagnosis, and Eastern Cooperative Oncology Group performance status of 2 or higher (TABLE).
Dr. El-Galaly and co-authors also calculated progression-free survival rates according to International Prognostic Index (IPI) score and updated relapse information (which were available only for the 512 patients in the Danish cohort). Cumulative incidences for relapse or death in the first two years of follow-up were 10 percent for the entire cohort, six percent for those with IPI score ≤2, and 21 percent for those with IPI score >2.
“Including serial routine imaging in the follow-up protocol for young DLBCL patients in first CR following R-CHOP does not seem to improve overall survival,” Dr. El-Galaly told ASH Clinical News. “It might not be the time to completely leave the tradition of routine imaging, but its use should be limited to patients with high-risk disease, at a minimum.”
Screening for asymptomatic DLBCL relapse can be beneficial if the following three essential conditions are present:
- The relapse is life-threatening
- The risk of relapse is high
- Early treatment of relapse is more effective
“We also feel it is important to look at all patients – not just patients with relapse – since the vast majority of patients exposed to serial imaging in an attempt to detect early relapse never benefit from the practice,” Dr. El-Galaly said. “They either stay in remission or present with clinical symptoms at the time of relapse.”
This study’s population-based design was a limitation, because the researchers were unable to assess the number of imaging procedures performed per patient.
“DLBCL relapse after first CR is infrequent, and the widespread use of routine imaging in Denmark did not translate into better survival,” the authors concluded. “This favors follow-up without routine imaging, and, more generally, a shift of focus from relapse detection to improved survivorship.”
El-Galaly TC, Jakobsen LH, Hutchings M, et al. Routine imaging for diffuse large B-cell lymphoma in first complete remission does not improve post-treatment survival: a Danish–Swedish population-based study. J Clin Oncol. 2015 October 5. [Epub ahead of print]
|TABLE. Overall Survival Determinants in Patients with DLBCL in First Complete Remission|
|Multivariable Cox Analysis|
|Hazard ratio (95% CI)||p Value|
|Age >60 years||2.29 (1.57-3.35)||<0.01|
|Elevated LDH||2.34 (1.43-.84)||<0.01|
|Stage 3-4 disease||0.90 (0.59-1.37)||0.6|
|Bulky disease (>10 cm)||1.47 (0.94-2.29)||0.09|
|ECOG performance status ≥2||1.75 (1.02-3.01)||0.04|
|B symptoms at diagnosis||1.65 (1.08-2.51)||0.02|