Diagnostic performance of FDG-PET/CT of post-transplant lymphoproliferative disorder and factors affecting diagnostic yield

Abstract

Purpose Post-transplant lymphoproliferative disorder (PTLD) is a serious complication after solid organ and hematopoietic stem cell transplantation, requiring a timely and accurate diagnosis. In this study, we evaluated the diagnostic performance of FDG-PET/CT in patients with suspected PTLD and examined if lactate dehydrogenase (LDH) levels, Epstein-Barr virus (EBV) load, or timing of FDG-PET/CT relate to detection performance of FDG-PET/CT. Methods This retrospective study included 91 consecutive patients with clinical suspicion of PTLD and a total of 97 FDG-PET/CT scans within an 8-year period. Pathology reports and a 2-year follow-up were used as the reference standard. Diagnostic performance of FDG-PET/CT for detection of PTLD as well as logistic regression analysis for factors expected to affect diagnostic yield were assessed. Results The diagnosis of PTLD was established in 34 patients (35%). Fifty-seven FDG-PET/CT scans (59%) were true negative, 29 (30%) were true positive, 6 (6%) false positive, and 5 (5%) false negative. Sensitivity of FDG-PET/CT for the detection of PTLD was 85%, specificity 90%, positive predictive value 83%, and negative predictive value 92%, with good inter-observer variability (k = 0.78). Of the parameters hypothesized to be associated with a true positive FDG-PET/CT result for the diagnosis of PTLD, only LDH was statistically significant (OR 1.03, p = 0.04). Conclusion FDG-PET/CT has a good diagnostic performance in patients suspected of PTLD, with a good inter-observer agreement. Only LDH levels seemed to influence the detection performance of FDG-PET/CT. EBV-DNA load and timing of FDG-PET/CT after transplantation did not affect FDG-PET/CT diagnostic yield.

18F-FDG PET/CT in patients with post-transplant lymphoproliferative disorders: so far so good

“…Among the main clinical features, only increased lactate dehydrogenase levels seemed to be correlated with a true positive 18 F-FDG PET/CT scan in PTLD patients. EBV-DNA load and timing of 18 F-FDG PET/CT after transplantation did not affect the diagnostic performance of 18 F-FDG PET/CT in PTLD [5]. The good diagnostic performance reported in this study suggests that 18 F-FDG PET/CT is a valuable imaging modality for detecting PTLD.…”

“…The article of Montes de Jesus et al recently published in EJNMMI provides further evidence on the usefulness of 18 F-FDG PET/CT in the management of patients with PTLD [5]. In this retrospective study, the authors evaluated the diagnostic performance of 18 F-FDG PET/CT in a significant population (n = 91) of patients with suspected PTLD examining the factors affecting the diagnostic yield of 18 F-FDG PET/CT.…”

Diagnostic Performance of 18F-FDG PET or PET/CT for Detection of Post-Transplant Lymphoproliferative Disorder: A Systematic Review and a Bivariate Meta-Analysis

“…No additional records were found screening the references of these articles. Therefore, five studies were included in the qualitative analysis (systematic review) and in the quantitative analysis (meta-analysis) [12][13][14][15][16].…”

“…The characteristics of the studies included in the systematic review are presented in Tables 1-4, whereas the overall quality assessment of the studies included in the meta-analysis is reported in Figure 2. Screening the selected databases, five articles evaluating the diagnostic performance of 18 F-FDG PET or PET/CT for detection of PTLD in 336 transplant recipients were selected (Table 1) [12][13][14][15][16]. All the selected articles were retrospective single-centre studies published from 2009 to 2019 by research groups from different countries, mainly from Europe.…”

“…False positive results of 18 F-FDG PET or PET/CT for detection of PTLD could be divided into two main categories: other tumors also showing high 18 F-FDG uptake, and infectious or inflammatory diseases also taking up 18 F-FDG. False-negative results occurred when PTLD lesions were located in areas of high physiological 18 F-FDG uptake, in cases of non-18 F-FDG avid PTLD (such some nondestructive and polymorphic PTLD lesions), and in cases erroneously interpreted as inflammatory lesions or other tumors [12][13][14][15][16].…”