¹⁸F-FDG PET for Posttherapy Assessment of Hodgkin's Disease and Aggressive Non-Hodgkin's Lymphoma: A Systematic Review

Abstract

Although studies have shown that 18 F-FDG PET, when used to assess the response of malignant lymphoma after treatment, has a strong ability to predict relapse, its diagnostic accuracy in clinical practice remains unclear. The aim of this study was to systematically review the diagnostic accuracy of 18 F-FDG PET in detecting residual disease at the completion of first-line therapy of Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL). Methods: We searched relevant articles from 1966 to July 2006 using MEDLINE, EMBASE, SCOPUS, Biological Abstracts, bibliographies, review articles, and textbooks without language restriction. One assessor (for non-English-language studies) or 2 assessors (for English-language studies) independently reviewed each article to abstract relevant study characteristics and results. Relevant individual patient data or subgroup data were provided by the investigators if they were unavailable from the publications. We estimated summary receiver operating characteristic curves and confidence regions for summary sensitivity and specificity. Results: Nineteen studies consisting of 474 HD and 254 aggressive NHL patients were included. These studies had heterogeneity and suboptimal methodologic quality and reporting. Reported ranges for the sensitivity and specificity of 18 F-FDG PET in predicting disease relapse were 0.50-1.00 and 0.67-1.00, respectively, for HD and 0.33-0.77 and 0.82-1.00, respectively, for NHL. These estimates were similar when conventional imaging tests showed a residual mass. For HD studies, the summary receiver operating characteristic curves were similar irrespective of whether a residual mass was detected by conventional tests. Factors explaining the variability of diagnostic estimates were not identified. Conclusion: Although currently available evidence is still limited, 18 F-FDG PET seems to have good diagnostic accuracy for assessing residual HD at the completion of first-line treatment. Clinical data on this use of 18 F-FDG PET for aggressive NHL are more limited. Prospective studies with a more rigorous research design, conduct, and reporting would more reliably reveal the clinical diagnostic accuracy of this imaging modality.

Primary mediastinal B‐cell lymphoma

“…69 A systemic review of PET studies has examined posttherapy response assessment in lymphoma. 70 In the studies reporting evaluation of residual masses in aggressive NHL, the demonstrated sensitivity of PET ranged from 33% to 87% and the specificity from 75% to 100%. These data clearly indicate that further evaluation is required before modifying planned therapy based upon FDG-PET evaluation alone in PMBL, and the false-positive rate in particular requires definition.…”

Advanced Hodgkin’s lymphoma: End-of-treatment FDG-PET should be maintained

“…HL is associated with a high rate of residual masses at the end of therapy, which are difficult to characterize as residual disease or not on conventional imaging. Therefore, a major milestone was the finding that end-of-treatment FDG-PET offers excellent prediction of progression-free-survival (PFS), even in the presence of a residual mass [8][9][10][11]. This finding led to the introduction of FDG-PET imaging in response criteria for HL [12].…”

PET Imaging for Treatment Response in Cancer

“…[1][2][3][4] More recently, a growing body of literature is reporting the use of FDG and other PET imaging agents in treatment response assessment. [5][6][7] In many cases, FDG PET has proved to be a reliable means of noninvasively observing response in various treatments.…”

“…[1][2][3][4] More recently, a growing body of literature is reporting the use of FDG and other PET imaging agents in treatment response assessment. [5][6][7] In many cases, FDG PET has proved to be a reliable means of noninvasively observing response in various treatments.Additionally, reliable determination of past treatment changes, including recurrent tumors and differentiation of benign and malignant lesions, will reduce morbidity and the cost of care in anatomic imaging. The Response Evaluation Criteria in Solid Tumors (RECIST) are a useful means to report quantitative changes in tumor size on CT scans in many different tumors in response to treatment.…”

“…Many authors have commented on what may be the most clinically relevant form of SUV when analyzing tumors, which include correction for blood glucose, lean body mass, and average tumor uptake. 7 Our group advocates the use of the SUV maximum (SUV max ) measurement for tumor characterization. With FDG, many reports state that tissue uptake correlates with tumor mitotic rate, cellularity, blood flow, and various cytogenetic abnormalities.…”