Prognostic value of interim FDG‐PET in Hodgkin lymphoma: systematic review and meta‐analysis

Abstract

SummaryThis study aimed to systematically review and meta-analyse the value of interim 18 F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in predicting treatment failure in Hodgkin lymphoma. MEDLINE was systematically searched for original studies that used standardized international criteria for interim FDG-PET interpretation. Included studies were methodologically assessed. Summary receiver operating characteristic (sROC) analysis was performed, and pooled sensitivity and specificity were calculated using a random effects model. Heterogeneity in diagnostic odds ratios (DORs) across studies was assessed and potential sources for interstudy heterogeneity were explored using subgroup analyses. Ten studies, comprising a total of 1389 Hodgkin lymphoma patients, were included. Sensitivity, specificity, positive predictive value and negative predictive value of interim FDG-PET for predicting treatment failure ranged between 0Á0-81Á5%, 72Á2-96Á6%, 0Á0-86Á0% and 84Á4-98Á6%, respectively. The area under the sROC curve was 0Á877. Pooled sensitivity and specificity were 70Á8% [95% confidence interval (CI): 64Á7-76Á4%] and 89Á9% (95% CI: 88Á0-91Á6%). There was heterogeneity in DORs across individual studies (I 2 = 72Á7). The overall prognostic value of interim FDG-PET appears to be moderate for excluding and relatively high for identifying treatment failure in Hodgkin lymphoma. However, interim FDG-PET cannot yet be implemented in routine clinical practice due to moderate-quality evidence and inter-study heterogeneity that cannot be fully explained yet.

Prognostic Value of Bone Marrow Tracer Uptake Pattern in Baseline PET Scans in Hodgkin Lymphoma: Results from an International Collaborative Study

“…The fact that patients with fPET 1 had a significantly worse treatment outcome (P 5 0.03) than did those with dPET 1 and nPET 1 could depend on a possible protective effect of patients with a dPET 1 , as witnessed by the younger age (36.5 vs. 41.8, P 5 0.002), and on the adverse prognostic meaning of a stage IV disease (26). However, when all the known clinical, biologic, and imaging variables were considered, the only strong significant predictive factor associated with a poor PFS in multivariate analysis was positive interim PET/ CT (P , 0.0001), in agreement with the large literature data (26,27). The good interobserver agreement in PET reporting points toward feasibility in clinical practice of these simple rules for BMI detection.…”

Response Assessment Criteria and Their Applications in Lymphoma: Part 2

“…The metaanalysis lent credence to interim PET by demonstrating pooled sensitivity and specificity values of 0.81 and 0.97, indicating accuracy comparable to that of end-of-treatment imaging (10). A more recent metaanalysis of 10 studies with 1,389 patients reported slightly lower pooled sensitivity and specificity values of 0.71 and 0.90, respectively (11).…”

Predictive Value of Interim [18F]Fluorodeoxyglucose–Positron Emission Tomography in Advanced-Stage Hodgkin Lymphoma Is Not Well Established

“…2 This meta-analysis showed mixed results among studies, including the subgroup of patients with advanced-stage HL. 2 In particular, studies reporting that a positive interim FDG-PET in advanced-stage HL resulted in low PFS were methodologically flawed, because these studies did not use histopathology or did not report whether histopathology was used to confirm residual disease and instead determined disease relapse by means of follow-up imaging studies. 3,4 Considering the high false-positive rate of follow-up FDG-PET, 5,6 the prognostic value of a positive interim FDG-PET result was likely thoroughly overestimated.…”

“…[2][3][4] The fact that only 60 patients were PET2 positive and the finding that 58 patients in the PET2-negative group experienced disease relapse indicate that at least approximately half of patients who might have benefited from treatment intensification had negative PET2 results. Note that the volume of FDG-active lymphomatous tissue decreases rapidly after treatment initiation.…”

“…Note that the volume of FDG-active lymphomatous tissue decreases rapidly after treatment initiation. 2,10 As a result of the limited spatial resolution of current PET systems, small residual lymphomatous deposits cannot be detected. This hypothesis is supported by the fact that patients with HL in the palliative setting treated with noncurative therapies or patients with incurable indolent non-HL treated with noncurative chemotherapy may achieve FDG-PET-negative status.…”