Pulmonary embolism in patients with COVID-19 and value of D-dimer assessment: a meta-analysis.

PURPOSE: To investigate, in a meta-analysis, the frequency of pulmonary embolism (PE) in patients with COVID-19 and whether D-dimer assessment may be useful to select patients for computed tomography pulmonary angiography (CTPA). METHODS: A systematic literature search was performed for original studies which reported the frequency of PE on CTPA in patients with COVID-19. The frequency of PE, the location of PE, and the standardized mean difference (SMD) of D-dimer levels between patients with and without PE were pooled by random effects models. RESULTS: Seventy-one studies were included. Pooled frequencies of PE in patients with COVID-19 at the emergency department (ED), general wards, and intensive care unit (ICU) were 17.9% (95% CI: 12.0-23.8%), 23.9% (95% CI: 15.2-32.7%), and 48.6% (95% CI: 41.0-56.1%), respectively. PE was more commonly located in peripheral than in main pulmonary arteries (pooled frequency of 65.3% [95% CI: 60.0-70.1%] vs. 32.9% [95% CI: 26.7-39.0%]; OR = 3.540 [95% CI: 2.308-5.431%]). Patients with PE had significantly higher D-dimer levels (pooled SMD of 1.096 [95% CI, 0.844-1.349]). D-dimer cutoff levels which have been used to identify patients with PE varied between 1000 and 4800 µg/L. CONCLUSION: The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries, which suggests local thrombosis to play a major role. D-dimer assessment may help to select patients with COVID-19 for CTPA, using D-dimer cutoff levels of at least 1000 µg/L. KEY POINTS: • The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. • PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries. • D-dimer levels are significantly higher in patients with COVID-19 who have PE.

Systematic review on the value of end-of-treatment FDG-PET in improving overall survival of lymphoma patients.

This study aimed to systematically review the value of end-of-treatment 18F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in improving overall survival (OS) of lymphoma patients. Medline was systematically searched for (1) randomized trials comparing the OS of patients who underwent end-of-treatment FDG-PET to those without and FDG-PET-based end-of-treatment evaluation and for (2) non-randomized studies comparing the OS of patients who underwent end-of-treatment FDG-PET to a (historical) cohort of patients without an FDG-PET-based end-of-treatment evaluation. The Medline search revealed 6284 articles. However, none of these reported data on the value of end-of-treatment FDG-PET in improving OS of lymphoma patients. In conclusion, the present systematic review reveals that there is currently no study at all that evaluates the value of end-of-treatment FDG-PET in improving OS of lymphoma patients. As a result, it remains unknown whether end-of-treatment FDG-PET increases OS and in which lymphoma subtype these examinations are of particular value. Future studies are required to demonstrate its value in this setting before it can be recommended as an evidence-based diagnostic tool by guidelines on the use of imaging in lymphoma.

Systematic Review and Meta-Analysis on the Value of Chest CT in the Diagnosis of Coronavirus Disease (COVID-19): Sol Scientiae, Illustra Nos.

OBJECTIVE. The purpose of this article is to systematically review and meta-analyze the diagnostic accuracy of chest CT in detecting coronavirus disease (COVID-19). MATERIALS AND METHODS. MEDLINE was systematically searched for publications on the diagnostic performance of chest CT in detecting COVID-19. Methodologic quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Meta-analysis was performed using a bivariate random-effects model. RESULTS. Six studies were included, comprising 1431 patients. All six studies included patients at high risk of COVID-19, and five studies explicitly reported that they included only symptomatic patients. Mean prevalence of COVID-19 was 47.9% (range, 27.6-85.4%). High or potential risk of bias was present throughout all QUADAS-2 domains in all six studies. Sensitivity ranged from 92.9% to 97.0%, and specificity ranged from 25.0% to 71.9%, with pooled estimates of 94.6% (95% CI, 91.9-96.4%) and 46.0% (95% CI, 31.9-60.7%), respectively. The included studies were statistically homogeneous in their estimates of sensitivity (p = 0.578) and statistically heterogeneous in their estimates of specificity (p < 0.001). CONCLUSION. Diagnostic accuracy studies on chest CT in COVID-19 suffer from methodologic quality issues. Chest CT appears to have a relatively high sensitivity in symptomatic patients at high risk of COVID-19, but it cannot exclude COVID-19. Specificity is poor. These data, along with other local factors such as COVID-19 prevalence, available real-time reverse transcriptase-polymerase chain reaction tests, staff, hospital, and CT scanning capacity, can be useful to healthcare professionals and policy makers to decide on the utility of chest CT for COVID-19 detection in the hospital setting.

Culture yield of repeat percutaneous image-guided biopsy after a negative initial biopsy in suspected spondylodiscitis: a systematic review.

OBJECTIVE: To systematically review the published data on the culture yield of a repeat (second) percutaneous image-guided biopsy after negative initial biopsy in suspected spondylodiscitis. MATERIALS AND METHODS: A systematic search was performed of the PubMed/Medline and Embase databases. The methodological quality of the studies included was assessed. The proportions of positive cultures among all initial biopsies and second biopsies (after a negative initial biopsy) were calculated for each study and assessed for heterogeneity (defined as I2 > 50%). RESULTS: Eight studies, comprising a total of 107 patients who underwent a second percutaneous image-guided biopsy after a culture-negative initial biopsy in suspected spondylodiscitis, were included. All eight studies were at risk of bias and were concerning with regard to applicability, particularly patient selection, flow of patients through the study, and timing of the biopsy. The proportions of positive cultures among all initial biopsies ranged from 10.3 to 52.5%, and were subject to heterogeneity (I2 = 73.7%). The proportions of positive cultures among all second biopsies after negative initial biopsy ranged from 0 to 60.0%, and were not subject to heterogeneity (I2 = 38.7%). CONCLUSION: Although a second percutaneous image-guided biopsy may have some value in patients with suspected spondylodiscitis, its exact value remains unclear, given the available poor-quality evidence. Future well-designed studies are needed to determine the role of a second percutaneous image-guided biopsy in this setting. Such studies should clearly describe the spectrum of patients that was selected for a second percutaneous image-guided biopsy, the method of biopsy, and differences compared with the first biopsy, if any.

CT-guided biopsy in suspected spondylodiscitis: microbiological yield, impact on antimicrobial treatment, and relationship with outcome.

PURPOSE: To investigate the clinical impact of CT-guided biopsy, as performed in routine clinical practice, in patients with suspected spondylodiscitis on MRI in terms of culture yield, impact on antimicrobial treatment, and outcome. METHODS: This study included 64 patients with MRI findings compatible with spondylodiscitis who underwent CT-guided biopsy. RESULTS: Initial CT-guided biopsies were culture-positive in 20/64 (31.3%, 95% confidence interval [CI] 21.2-43.3%). Repeat CT-guided biopsies (after initial negative biopsy) were culture-positive in an additional 5/15 (33.3%, 95% CI 15.2-58.3%). Serum leukocytes, C-reactive protein, pre-biopsy use of antibiotics, neurological symptoms, MRI findings, vertebral height loss, and hyperkyphosis were not significantly different between culture-positive and culture-negative cases (P = 0.214-1.000); 75% (15/20) of initial CT-guided biopsies that were culture-positive provided additional information to clinicians for guiding antibiotic treatment. Sixty-two of 64 patients (96.9%, 95% CI 89.3-99.1%) would have been adequately treated if a strategy was followed that would subject all patients without clinical findings suspicious for "atypical" microorganisms and negative blood cultures to empirical antibiotics (i.e., clindamycin for coverage of Gram-positive bacteria) without using biopsy results to determine the optimal antibiotic regimen. Outcome within 6 months (development of neurologic or orthopedic complications, surgery, and death) was not significantly different (P = 0.751) between culture-positive and culture-negative patients. CONCLUSIONS: Although CT-guided biopsies are culture-positive in a minority of cases, the majority of positive cultures are useful to tailor antibiotic treatment. Empirical treatment with clindamycin may cover almost all micro-organisms in positive biopsy specimens, provided patients are not immunocompromised. Outcome appears similar between culture-positive and culture-negative patients.

Surveillance MRI for the detection of locally recurrent Ewing sarcoma seems futile.

PURPOSE: To determine the frequency of locally recurrent Ewing sarcoma on surveillance MRI and the outcome of these patients. MATERIALS AND METHODS: This retrospective single-center study included all patients with newly diagnosed Ewing sarcoma who underwent surveillance MRI of the primary tumor location after primary treatment between 1997 and 2016. RESULTS: Thirty-two patients underwent a total of 176 local surveillance MRI scans, yielding an average of 5.5 ± 4.4 MRI scans per patient. Follow-up time of surveillance MRI after completion of primary treatment ranged between 1 and 111 months. Surveillance MRI detected five (15.6%) locally recurrent Ewing sarcomas, at 2, 4, 6, 6, and 7 months after completion of primary treatment, of whom three also had simultaneous recurrent (metastatic) disease elsewhere. Two patients had recurrent metastatic disease without any signs of locally recurrent disease on surveillance MRI. All five patients with locally recurrent disease on surveillance MRI died, at 2, 4, 5, 8, and 9 months after local recurrence detection. Patients with locally recurrent disease had a significantly worse overall survival than patients without locally recurrent disease (log-rank test, P < 0.0001). CONCLUSIONS: A limited number of patients have locally recurrent Ewing sarcoma on surveillance MRI. These patients often have simultaneous recurrent (metastatic) disease elsewhere, and their outcome is poor. Moreover, some patients present without locally recurrent disease on MRI but disease recurrence elsewhere. Therefore, surveillance MRI currently seems to have little value and should be reconsidered, also given the costs and the repeated exposure of surviving patients to gadolinium-based contrast agents.

Pretransplant FDG-PET in aggressive non-Hodgkin lymphoma: systematic review and meta-analysis.

This study aimed to systematically review and meta-analyze the value of pretransplant FDG-PET in predicting outcome after autologous stem cell transplantation in aggressive non-Hodgkin lymphoma. MEDLINE was systematically searched; included studies were methodologically assessed and meta-analyzed, when possible. Overall methodological quality of included studies (n = 11) was poor, with moderate risk of bias in the domains of study participation (n = 7) and prognostic factor measurement (n = 7), and high risk of bias in the domains of outcome measurement (n = 10), and study confounding (n = 11). In all aggressive non-Hodgkin lymphomas, pooled sensitivity and specificity were 54.0% and 73.1% in predicting treatment failure, and 54.5% and 68.7% in predicting death. Because of interstudy heterogeneity, additional subgroup analyses were performed. In newly diagnosed aggressive non-Hodgkin lymphoma, pooled sensitivity and specificity were 20.0% and 70.0% in predicting treatment failure, and 8.3% % and 30.5% in predicting death. In refractory/relapsed aggressive non-Hodgkin lymphoma, pooled sensitivity and specificity were 68.1% and 72.1% in predicting treatment failure, and 77.3% and 69.6% in predicting death. At present, pretransplant FDG-PET cannot be recommended in aggressive non-Hodgkin lymphoma, because available studies suffer from major methodological flaws, and reported prognostic estimates are low (i.e., poor in newly diagnosed and moderate in refractory/relapsed aggressive non-Hodgkin lymphoma).

Systematic Review on the Additional Value of 18F-Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography in Staging Follicular Lymphoma.

PURPOSE: This study aimed to systematically review the additional value of F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) to computed tomography (CT) for staging newly diagnosed follicular lymphoma in terms of Ann Arbor staging and Follicular Lymphoma International Prognostic Index (FLIPI) risk stratification. MATERIALS AND METHODS: The PubMed/MEDLINE database was searched for relevant original studies. Included studies were methodologically assessed. Data on the frequency of FDG-PET-induced changes in Ann Arbor stage and FLIPI score relative to CT were (meta-)analyzed when possible. RESULTS: Seven studies with a total of 349 patients were included. Overall, studies were of very poor methodological quality, with lack of histological verification of additionally detected lesions at FDG-PET in almost all cases and only 1 study that exclusively included patients with CT-based limited nonbulky stage I to II disease. The proportion of patients who were upstaged by FDG-PET compared with CT ranged from 0.0% to 45.2%, with a pooled summary proportion of 18.7% (95% confidence interval, 10.8%-30.4%). The single study that only included patients with CT-based limited nonbulky stage I to II disease reported FDG-PET-induced upstaging in 40.5% (95% confidence interval, 27.0%-55.5%) of cases. No study reported data on the influence of FDG-PET on FLIPI risk stratification. CONCLUSIONS: Although upstaging by FDG-PET compared with CT occurs in a considerable proportion of patients, the available studies on this topic have numerous methodological errors. Data on FDG-PET-induced FLIPI risk stratification changes relative to CT are lacking. Future well-designed studies are needed before FDG-PET can be recommended for routine pretreatment staging of follicular lymphoma.

Malignancy rate of biopsied suspicious bone lesions identified on FDG PET/CT.

PURPOSE: To determine the malignancy rate of bone lesions identified on FDG PET/CT in patients who have undergone CT-guided biopsy because of the suspicion of malignancy. METHODS: This single-centre retrospective study spanned eight consecutive years and included all patients who underwent both FDG PET/CT and CT-guided bone biopsy because of the suspicion of malignancy. The positive predictive value (PPV) for malignancy was calculated, and different patient and imaging characteristics were compared between malignant and benign bone lesions. RESULTS: Of 102 included patients with bone lesions that all showed FDG uptake exceeding mediastinal uptake, bone biopsy showed a malignant lesion in 91 patients, yielding a PPV for malignancy of 89.2 % (95 % CI 81.7 - 93.9 %). In the 94 patients with bone lesions that showed FDG uptake exceeding liver uptake, bone biopsy showed a malignant lesion in 83 patients, yielding a PPV for malignancy of 88.3 % (95 % CI 80.1 - 93.5 %). Higher age, bone marrow replacement of the lesion seen on CT, expansion of the lesion seen on CT, and presence of multifocal lesions on FDG PET/CT were significantly more frequent in patients with malignant lesions than in those with benign bone lesions (P = 0.044, P = 0.009, P = 0.015, and P = 0.019, respectively). Furthermore, there was a trend towards a higher incidence of cortical destruction (P = 0.056) and surrounding soft tissue mass (P = 0.063) in patients with malignant bone lesions. CONCLUSION: The PPV for malignancy of suspicious bone lesions identified on FDG PET/CT is not sufficiently high to justify changes in patient management without histopathological confirmation. Nevertheless, ancillary patient and imaging characteristics may increase the likelihood of a malignant bone lesion.

Prognostic value of pretransplant FDG-PET in refractory/relapsed Hodgkin lymphoma treated with autologous stem cell transplantation: systematic review and meta-analysis.

This study aimed to systematically review the prognostic value of pretransplant (18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in refractory/relapsed Hodgkin lymphoma treated with autologous stem cell transplantation (SCT). MEDLINE was systematically searched for appropriate studies. Included studies were methodologically appraised. Results of individual studies were meta-analyzed, if possible. Eleven studies, comprising a total of 745 refractory/relapsed Hodgkin lymphoma patients who underwent FDG-PET before autologous SCT, were included. The overall methodological quality of these studies was moderate. The proportion of pretransplant FDG-PET positive patients ranged between 25 and 65.2 %. Progression-free survival ranged between 0 and 52 % in pretransplant FDG-PET positive patients, and between 55 and 85 % in pretransplant FDG-PET negative patients. Overall survival ranged between 17 and 77 % in pretransplant FDG-PET positive patients, and between 78 and 100 % in FDG-PET negative patients. Based on five studies that provided sufficient data for meta-analysis, pooled sensitivity and specificity of pretransplant FDG-PET in predicting treatment failure (i.e., either progressive, residual, or relapsed disease) were 67.2 % (95 % confidence interval [CI] 58.2-75.3 %) and 70.7 % (95 % CI 64.2-76.5 %), respectively. Based on two studies that provided sufficient data for meta-analysis, pooled sensitivity and specificity of pretransplant FDG-PET in predicting death during follow-up were 74.4 % (95 % CI 58.8-86.5 %) and 58.0 % (95 % CI 49.3-66.3 %), respectively. In conclusion, the moderate quality evidence suggests pretransplant FDG-PET to have value in predicting outcome in refractory/relapsed Hodgkin lymphoma patients treated with autologous SCT. Nevertheless, a considerable proportion of pretransplant FDG-PET positive patients remains disease free and a considerable proportion of pretransplant FDG-PET negative patients develops disease relapse after autologous SCT.

Prognostic value of interim and end-of-treatment FDG-PET in follicular lymphoma: a systematic review.

This study aimed to systematically review the prognostic value of interim and end-of-treatment (18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in follicular lymphoma during and after first-line therapy. The PubMed/MEDLINE database was searched for relevant original studies. Included studies were methodologically assessed, and their results were extracted and descriptively analyzed. Three studies on the prognostic value of interim FDG-PET and eight studies on the prognostic value of end-of-treatment FDG-PET were included. Overall, studies were of poor methodological quality. In addition, there was incomplete reporting of progression-free survival (PFS) and overall survival (OS) data by several studies, and none of the studies incorporated the Follicular Lymphoma International Prognostic Index (FLIPI) in the OS analyses. Two studies reported no significant difference in PFS between interim FDG-PET positive and negative patients, whereas one study reported a significant difference in PFS between the two groups. Two studies reported no significant difference in OS between interim FDG-PET positive and negative patients. Five studies reported end-of-treatment FDG-PET positive patients to have a significantly worse PFS than end-of-treatment FDG-PET negative patients, and one study reported a non-significant trend towards a worse PFS for end-of-treatment FDG-PET positive patients. Three studies reported end-of-treatment FDG-PET positive patients to have a significantly worse OS than end-of-treatment FDG-PET negative patients. In conclusion, the available evidence does not support the use of interim FDG-PET in follicular lymphoma. Although published studies suggest end-of-treatment FDG-PET to be predictive of PFS and OS, they suffer from numerous biases and failure to correct OS prediction for the FLIPI.

Systematic review and meta-analysis on the prognostic value of complete remission status at FDG-PET in Hodgkin lymphoma after completion of first-line therapy.

This study aimed to systematically review and meta-analyze the prognostic value of complete remission status at 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in Hodgkin lymphoma after completion of first-line therapy. A systematic literature search was performed in the MEDLINE database for suitable original articles. The included studies were methodologically assessed using the Quality In Prognosis Studies tool. The proportion of patients who developed disease relapse during follow-up, among those patients who were in complete remission according to FDG-PET at the completion of first-line therapy, was calculated for each included study. Heterogeneity in disease relapse proportions across individual studies was assessed using the I2 statistic, with heterogeneity regarded present if I2<50 %. Weighted summary disease relapse proportion was calculated using either a random effects model (if I2>50) or a fixed effects model (if I2≤50). Ten studies comprising a total number of 1137 Hodgkin lymphoma patients with complete remission status according to FDG-PET after completion of first-line therapy were included. Overall methodological quality of included studies was reasonably good. The disease relapse rate during follow-up among all patients with complete remission status at end-of-treatment FDG-PET ranged from 0 to 26.7 %, with a weighted summary proportion of 7.5 % (95 % confidence interval 3.9­13.8 %) using the random effects model (I2=88.3 %). In conclusion, although the disease relapse rate in Hodgkin lymphoma patients who achieve an FDG-PET-based complete remission after first-line therapy is low from an absolute point of view, it is actually high when considering the generally favorable outcome of Hodgkin lymphoma.

Controversies on the prognostic value of interim FDG-PET in advanced-stage Hodgkin lymphoma.

Hodgkin lymphoma, even in advanced-stage, is a highly curable malignancy, but treatment is associated with short-term toxicity and long-term side effects. Early predictive markers are required to identify those patients who do not require the full-length standard therapy (and thus qualify for therapy de-escalation) and those patients who will not be cured by standard therapy (and thus qualify for therapy escalation). Multiple trials have assessed the value of 18 F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) after a few cycles of chemotherapy (also known as 'interim FDG-PET') in predicting outcome in advanced-stage Hodgkin lymphoma. Furthermore, multiple interim FDG-PET-adapted trials, in which patients with positive interim FDG-PET scans are assigned to escalated therapies, and patients with negative interim FDG-PET scans are assigned to de-escalated therapies, have recently been published or are currently ongoing, with generally heterogeneous results. The present article reports the currently available evidence (and controversies) on the prognostic value of interim FDG-PET in advanced-stage Hodgkin lymphoma in patients with positive and negative interim FDG-PET findings following continuation of standard chemotherapy or escalated/de-escalated therapy.

Where Does Diffuse Large B-Cell Lymphoma Relapse?

OBJECTIVE: This study aimed to investigate the anatomic pattern of disease spread at first disease relapse compared with baseline in diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: All patients who were newly diagnosed as having DLBCL between January 2004 and June 2014 who initially achieved complete remission but who eventually developed relapsed disease during follow-up were retrospectively identified. Available histological and imaging data were used to determine which nodal regions and extranodal locations were involved at relapse. RESULTS: A total of 21 patients with relapsed DLBCL were included, of whom 8 (38.1%) presented with disease relapse at previously involved sites only, 7 (33.3%) presented with disease relapse at both previously involved and new sites, and 6 (28.6%) presented with disease relapse at new sites only. A total of 57 nodal stations and 34 extranodal locations were involved in all 21 relapsed DLBCL patients. Of these 57 involved nodal regions, 47 (82.5%) were also involved at baseline, whereas 10 (17.5%) were not involved at baseline. Of the 34 involved extranodal locations, 17 (50.0%) were also involved at baseline, whereas 17 (50.0%) were not involved at baseline. CONCLUSIONS: Relapsed DLBCL generally tends to affect previously involved sites, although close to one third of patients seem to have disease recurrence exclusively in previously uninvolved sites. The great majority of involved nodal stations at relapse are also involved at baseline, whereas only one half of involved extranodal locations at relapse are involved at baseline.

Prognostic value of complete remission status at end-of-treatment FDG-PET in R-CHOP-treated diffuse large B-cell lymphoma: systematic review and meta-analysis.

This study systematically reviewed and meta-analysed the prognostic value of complete remission status at end-of-treatment (18) F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP). The systematic PubMed/MEDLINE search yielded seven suitable studies comprising a total of 737 R-CHOP-treated DLBCL patients who were in complete remission at end-of-treatment FDG-PET. Overall, the methodological quality of included studies was reasonable. The disease relapse rate among all patients with complete remission status according to end-of-treatment FDG-PET ranged from 7·0% to 20·0%, with a weighted summary proportion of 13·7%. Five of seven studies reported progression-free survival (PFS) of these patients at various specific time points, i.e., 2-year PFS (n = 1), estimated 3-year PFS (n = 3) and 5-year PFS (n = 1), which was 83%, 85-86·4% and 75%, respectively. Three of seven studies reported overall survival (OS) of these patients at various specific time points, i.e., estimated 3-year OS (n = 2) and estimated 5-year OS (n = 1), which were 90%, 93·6% and 83%, respectively. In conclusion, a non-negligible proportion of R-CHOP-treated DLBCL patients who achieve complete remission according to end-of-treatment FDG-PET experiences disease relapse during follow-up.

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

This 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 inter-study 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 0.0-81.5%, 72.2-96.6%, 0.0-86.0% and 84.4-98.6%, respectively. The area under the sROC curve was 0.877. Pooled sensitivity and specificity were 70.8% [95% confidence interval (CI): 64.7-76.4%] and 89.9% (95% CI: 88.0-91.6%). There was heterogeneity in DORs across individual studies (I2 = 72.7). 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.

CT-based versus FDG-PET/CT-based NCCN international prognostic index risk stratification in DLBCL.

BACKGROUND: This study compared CT-based and (18)F-fluoro-2-deoxy-D-glucose PET/CT (FDG-PET/CT)-based NCCN International Prognostic Index (NCCN-IPI) risk stratification in newly diagnosed diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: This retrospective study included 57 patients with newly diagnosed DLBCL who had undergone both (oral and intravenous contrast-enhanced full-dose) diagnostic CT and FDG-PET/CT. Diagnostic CT only and FDG-PET/CT were evaluated separately, and corresponding NCCN-IPI scores for the 2 datasets (NCCN-IPICT and NCCN-IPIPET/CT) were calculated. Percentages of agreement and weighted k statistic between NCCN-IPICT and NCCN-IPIPET/CT scoring with regard to the formation of low-, low-intermediate-, high-intermediate-, and high-risk groups were calculated. RESULTS: In 47 of 57 patients (82.5%; 95% CI, 70.4-90.4), diagnostic CT alone was in agreement with FDG-PET/CT with regard to the formation of low-, low-intermediate-, high-intermediate-, and high-risk NCCN-IPI groups, but not in the remaining 10 patients (17.5%; 95% CI, 9.6%-29.6%). All NCCN-IPI disagreements between diagnostic CT and FDG-PET/CT were from the detection of additional lesions by the latter, most of them being bone marrow lesions. Agreement between NCCN-IPICT and NCCN-IPIPET/CT with regard to the formation of low-, low-intermediate-, high-intermediate-, and high-risk groups was considered good (k=0.771). CONCLUSIONS: Although agreement between NCCN-IPICT and NCCN-IPIPET/CT risk stratification is generally good, FDG-PET/CT results in higher NCCN-IPI risk stratifications in a non-negligible proportion of patients. Future studies should investigate the prognostic implications of these imaging-based differences in NCCN-IPI scoring.