Radiation-Induced Giant Cell Granuloma Mimicking Relapsed Hodgkin Lymphoma at FDG-PET/CT.

A 22-year-old woman was diagnosed with intermediate risk stage II Hodgkin lymphoma and treated with three cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by involved-field radiation therapy. A complete metabolic remission was achieved after two cycles of ABVD, which was maintained until three years after completion of treatment. Follow-up FDG-PET/CT four years after completion of treatment, however, showed a new FDG-avid (Deauville score of 4) lesion in the right scapula, suggesting relapsed disease. Computer tomography (CT)-guided biopsy of this lesion was performed and subsequent histological examination revealed a radiation-induced giant cell granuloma.

Current Pathologic Scoring Systems for Metal-on-metal THA Revisions are not Reproducible.

BACKGROUND: The aseptic lymphocyte vasculitis-associated lesion (ALVAL) score and the modified Oxford ALVAL score are frequently used scoring methods to evaluate the morphologic features of periprosthetic tissues around metal-on-metal (MoM) hip implants. Except for the initial studies of these two morphology scoring methods, to our knowledge, no other studies have reported on intraclass correlation coefficient (ICC) values for interobserver reliability of these scoring methods. QUESTIONS/PURPOSES: Are the ALVAL and Oxford ALVAL scores reproducible? METHODS: The periprosthetic tissue of 37 revisions of 36 patients with failed MoM THAs were independently scored by three experienced pathologists using ALVAL and Oxford ALVAL scoring methods. All patients were included who underwent revision surgery in our hospital until January 2013, with a large-head MoM prosthesis and also met the criteria: blood serum cobalt levels, available MRI scan, and intraarticular cobalt levels. The population included 26 patients with pseudotumors diagnosed by two radiologists using the method described by Matthies et al. The ALVAL describes morphologic features of the synovial lining, tissue organization, and inflammatory cell infiltrate in periprosthetic tissues. The Oxford-ALVAL score uses a semiquantitative measure of the immune response which should be easier to score. RESULTS: The ALVAL score showed an ICC of 0.38 (95% CI, 0.18-0.58) (fair) for the sum score and this improved up to 0.50 (95% CI, 0.31-0.68) (moderate) using the modified Oxford ALVAL score. The individual parameters of the ALVAL score showed an ICC for the scoring of inflammatory infiltrate of 0.37 (95% CI, 0.17-0.57), an ICC of 0.32 (95% CI, 0.12-0.53) for the scoring of tissue organization, and an ICC of 0.14 (95% CI, -0.04 to 0.34) for synovial lining. CONCLUSIONS: Scoring morphologic features of MoM tissue is not reproducible using the ALVAL score or the Oxford ALVAL score. This may reflect heterogeneous morphologic features in tumor tissue and between different tumor tissue samples that cannot be reliably quantified by pathologists using the parameters of these two scoring methods. An alternative, simplified scoring system should be developed to improve the interrater agreement. LEVEL OF EVIDENCE: Level III, diagnostic study.

Benign Bone Conditions That May Be FDG-avid and Mimic Malignancy.

Positron emission tomography with the radiotracer 18F-fluoro-2-deoxy-d-glucose (FDG) plays an important role in the evaluation of bone pathology. However, FDG is not a cancer-specific agent, and knowledge of the differential diagnosis of benign FDG-avid bone alterations that may resemble malignancy is important for correct patient management, including the avoidance of unnecessary additional invasive tests such as bone biopsy. This review summarizes and illustrates the spectrum of benign bone conditions that may be FDG-avid and mimic malignancy, including osteomyelitis, bone lesions due to benign systemic diseases (Brown tumor, Erdheim-Chester disease, Gaucher disease, gout and other types of arthritis, Langerhans cell histiocytosis, and sarcoidosis), benign primary bone lesions (bone cysts, chondroblastoma, chondromyxoid fibroma, desmoplastic fibroma, enchondroma, giant cell tumor and granuloma, hemangioma, nonossifying fibroma, and osteoid osteoma and osteoblastoma), and a group of miscellaneous benign bone conditions (post bone marrow biopsy or harvest status, bone marrow hyperplasia, fibrous dysplasia, fractures, osteonecrosis, Paget disease of bone, particle disease, and Schmorl nodes). Several ancillary clinical and imaging findings may be helpful in discriminating benign from malignant FDG-avid bone lesions. However, this distinction is sometimes difficult or even impossible, and tissue acquisition will be required to establish the final diagnosis.

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.

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.

Variety in bone marrow 18F-FDG uptake in Hodgkin lymphoma patients without lymphomatous bone marrow involvement: does it have an explanation?

OBJECTIVE: To directly correlate fluorine-18 fluoro-2-deoxy-D-glucose (F-FDG) uptake of the iliac crest, as determined with PET, with both spatially matched histological bone marrow parameters and laboratory markers in Hodgkin lymphoma patients without lymphomatous bone marrow involvement at bone marrow biopsy. MATERIALS AND METHODS: This retrospective study included 21 patients with newly diagnosed Hodgkin lymphoma who underwent F-FDG-PET and who had a lymphoma-negative bone marrow biopsy of the right posterior iliac crest. F-FDG-PET maximum standardized uptake value (SUVmax) was measured in the right posterior iliac crest and correlated to histological bone marrow parameters (cellularity, myeloid/erythroid ratio, degree of fibrosis, and reactive T- and B-lymphocytes) and laboratory markers (hemoglobin, C-reactive protein lactate dehydrogenase, and leukocyte and thrombocyte counts) using Pearson's correlation coefficient (R) for Gaussian data or Kendall's tau (τ) for non-Gaussian data. RESULTS: There was a significant moderate correlation between F-FDG-PET SUVmax and cellularity of the iliac crest (R=0.519, P=0.016). Furthermore, there was a significant strong inverse correlation between F-FDG-PET SUVmax of the iliac crest and hemoglobin level (R=-0.661, P=0.001) and there was a significant moderate correlation between F-FDG-PET SUVmax of the iliac crest and C-reactive protein level (τ=0.441, P=0.007). All other correlations, including F-FDG-PET SUVmax of the right iliac crest versus reactive T- and B-lymphocytes in the bone marrow, were not significant. CONCLUSION: The observations suggest increased bone marrow F-FDG uptake to be caused by red marrow hyperplasia because of anemia in Hodgkin lymphoma. Increased bone marrow F-FDG uptake is unlikely to be caused by inflammatory bone marrow changes.

Tumor necrosis at FDG-PET is an independent predictor of outcome in diffuse large B-cell lymphoma.

PURPOSE: To determine the prognostic performance of tumor necrosis at FDG-PET in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) who are treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy. MATERIALS AND METHODS: 108 patients with newly diagnosed DLBCL who underwent FDG-PET before R-CHOP therapy were retrospectively included. Lymphomatous sites at FDG-PET were assessed for the presence of a photopenic area, in keeping with tumor necrosis. Univariate and multivariate Cox regression analyses were performed to determine the associations of tumor necrosis and National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) with progression-free survival (PFS) and overall survival (OS). RESULTS: On univariate Cox regression analysis, both tumor necrosis and higher NCCN-IPI risk groups were significantly associated with PFS (P=0.024 and P<0.001, respectively) and OS (P=0.034 and P<0.001, respectively). On multivariate Cox regression analysis, both tumor necrosis and the NCCN-IPI were independent significant predictors for PFS (P=0.007, hazard ratio: 2.723 [95% confidence interval: 1.324-5.597] and P<0.001, hazard ratio: 2.952 [95% confidence interval: 1.876-4.646], respectively) and OS (P=0.009, hazard ratio: 2.794 [95% confidence interval: 1.305-5.985] and P<0.001, hazard ratio: 2.813 [95% confidence interval: 1.724-4.587], respectively). CONCLUSION: Tumor necrosis at FDG-PET is an NCCN-IPI-independent predictor of outcome in DLBCL.

Brain glucose metabolism in diffuse large B-cell lymphoma patients as assessed with FDG-PET: impact on outcome and chemotherapy effects.

BACKGROUND: There is a lack of data on the effect of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy on brain glucose metabolism of diffuse large B-cell lymphoma (DLBCL) patients, as measured by 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET). Moreover, the prognostic value of brain glucose metabolism measurements is currently unknown. PURPOSE: To investigate the use of FDG-PET for measurement of brain glucose metabolism in R-CHOP-treated DLBCL patients, and to assess its prognostic value. MATERIAL AND METHODS: This retrospective study included DLBCL patients who underwent FDG-PET including the brain. FDG-PET metabolic volume products (MVPs) of the entire brain, cerebral cortex, basal ganglia, and cerebellum were measured, before and after R-CHOP therapy. Whole-body total lesion glycolysis (TLG) was also measured. RESULTS: Thirty-eight patients were included, of whom 18 had an appropriate end-of-treatment FDG-PET scan. There were no significant differences (P > 0.199) between pre- and post-treatment brain glucose metabolism metrics. Low basal ganglia MVP was associated with a significantly worse progression-free survival (PFS) and overall survival (OS) (P = 0.020 and P = 0.032), and low cerebellar MVP was associated with a significantly worse OS (P = 0.034). There were non-significant very weak correlations between pretreatment brain glucose metabolism metrics and TLG. In the multivariate Cox regression, only the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) remained an independent predictor of PFS (hazard ratio 3.787, P = 0.007) and OS (hazard ratio 2.903, P = 0.0345). CONCLUSION: Brain glucose metabolism was not affected by R-CHOP therapy. Low pretreatment brain glucose metabolism was associated with a worse outcome, but did not surpass the predictive value of the NCCN-IPI.

Prognostic Value of Anemia and C-Reactive Protein Levels in Diffuse Large B-Cell Lymphoma.

PURPOSE: To determine the prognostic value of pretreatment anemia, pretreatment elevated C-reactive protein (CRP) levels, and 6-month posttreatment anemia in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) treated with rituximab, cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisolone (R-CHOP). PATIENTS AND METHODS: A total of 104 patients with newly diagnosed DLBCL were retrospectively included. Pretreatment hemoglobin and CRP levels and 6-month posttreatment hemoglobin levels were measured. Cox regression analyses were used to determine the associations of laboratory assessments and National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) risk groups with progression-free survival (PFS) and overall survival (OS). RESULTS: Pretreatment anemia, elevated pretreatment CRP levels, and higher risk NCCN-IPI groups were significantly associated with reduced PFS and OS (P = .001 and P = .003 for pretreatment anemia, P = .035 and P = .029 for elevated CRP, and P < .001 and P < .001 for higher risk NCCN-IPI groups). On multivariate Cox regression analysis, only the NCCN-IPI risk group remained as an independent significant predictor for PFS (P < .001) and OS (P < .001). In the subgroup of patients in complete remission 6 months after chemotherapy (n = 80), 6-month posttreatment anemia was significantly associated with reduced PFS (P = .046) but not OS (P = .062), and higher risk NCCN-IPI groups were significantly associated with both reduced PFS (P = .008) and OS (P = .017). On multivariate Cox regression analysis, only the NCCN-IPI group remained an independent significant predictor for PFS (P = .008) and OS (P = .017). CONCLUSION: Pretreatment anemia, pretreatment CRP levels, and 6-month posttreatment anemia are significantly associated with poor outcome, but were not proven to be of additional prognostic value to the current risk stratification index for DLBCL.

Residual Anatomical Disease in Diffuse Large B-Cell Lymphoma Patients With FDG-PET-Based Complete Response After First-Line R-CHOP Therapy: Does It Have Any Prognostic Value?

OBJECTIVE: This study aimed to determine the prognostic value of residual anatomical disease, including its size and reduction relative to baseline, in diffuse large B-cell lymphoma patients who have F-fluoro-2-deoxy-d-glucose positron emission tomography-based complete response after first-line R-CHOP therapy. METHODS: This retrospective study included 47 patients. In patients with computed tomography (CT)-based residual disease, the size of the largest residual lesion (Resmax) and the sum of the sizes of all residual lesions (Restotal) were measured, and their reductions relative to baseline (ΔResmax and ΔRestotal) were calculated. RESULTS: Patients with high-risk National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) scores had significantly lower progression-free survival (PFS) and overall survival (OS) than patients with low-risk NCCN-IPI scores (P = 0.032 and P = 0.022). In contrast, patients with residual lesions at CT had no significantly lower PFS and OS than those without (P = 0.531 and P = 0.801). In the subpopulation with CT-based residual disease, patients with high Resmax, high Restotal, low ΔResmax, and low ΔRestotal had no significantly different PFS and OS than those with low Resmax, low Restotal, high ΔResmax, and high ΔRestotal (P = 0.980 and P = 0.790, P = 0.423 and P = 0.229, P = 0.923 and P = 0.893, and P = 0.923 and P = 0.893, respectively). CONCLUSIONS: The NCCN-IPI retains its prognostic value in diffuse large B-cell lymphoma patients with F-fluoro-2-deoxy-d-glucose positron emission tomography-based complete response after first-line R-CHOP therapy. However, the presence of residual anatomical disease, including its size and reduction relative to baseline, has no prognostic value in these patients.

Does the presence of tumor-induced cortical bone destruction at CT have any prognostic value in newly diagnosed diffuse large B-cell lymphoma?

PURPOSE: To determine the prognostic value of tumor-induced cortical bone destruction at computed tomography (CT) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: This retrospective study included 105 patients with newly diagnosed DLBCL who had undergone CT and bone marrow biopsy (BMB) before R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisolone) chemo-immunotherapy. Cox regression analyses were used to determine the associations of cortical bone status at CT (absence vs. presence of tumor-induced cortical bone destruction), BMB findings (negative vs. positive for lymphomatous involvement), and dichotomized National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) strata (low risk vs. high risk) with progression-free survival (PFS) and overall survival (OS). RESULTS: Univariate Cox regression analysis indicated that cortical bone status at CT was no significant predictor of either PFS or OS (p = 0.358 and p = 0.560, respectively), whereas BMB findings (p = 0.002 and p = 0.013, respectively) and dichotomized NCCN-IPI risk strata (p = 0.002 and p = 0.003, respectively) were significant predictors of both PFS and OS. In the multivariate Cox proportional hazards model, only the dichotomized NCCN-IPI score was an independent predictive factor of PFS and OS (p = 0.004 and p = 0.003, respectively). CONCLUSIONS: The presence of tumor-induced cortical bone destruction at CT was not found to have any prognostic implications in newly diagnosed DLBCL.

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.

Prognostic value of tumor necrosis at CT in diffuse large B-cell lymphoma.

OBJECTIVE: To determine the prognostic value of tumor necrosis at computed tomography (CT) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: This retrospective study included 51 patients with newly diagnosed DLBCL who had undergone both unenhanced and intravenous contrast-enhanced CT before R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone) chemo-immunotherapy. Presence of tumor necrosis was visually and quantitatively assessed at CT. Associations between tumor necrosis status at CT and the National Comprehensive Cancer Network (NCCN) International Prognostic Index (IPI) factors were assessed. Cox regression analysis was used to determine the prognostic impact of NCCN-IPI scores and tumor necrosis status at CT. RESULTS: There were no correlations between tumor necrosis status at CT and the NCCN-IPI factors categorized age (ρ=-0.042, P=0.765), categorized lactate dehydrogenase (LDH) ratio (ρ=0.201, P=0.156), extranodal disease in major organs (φ=-0.245, P=0.083), Ann Arbor stage III/IV disease (φ=-0.208, P=0.141), and Eastern Cooperative Oncology Group (ECOG) performance status (φ=0.015, P=0.914). In the multivariate Cox proportional hazards model, only tumor necrosis status at CT was an independent predictive factor of progression-free survival (P=0.003) and overall survival (P=0.004). CONCLUSION: The findings of this study indicate the prognostic potential of tumor necrosis at CT in newly diagnosed DLBCL.

Bone marrow biopsy in diffuse large B-cell lymphoma: useful or redundant test?

PURPOSE: To determine the additional value of bone marrow biopsy (BMB) in the standard staging work-up of patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL), in terms of risk assessment and treatment planning. MATERIAL AND METHODS: A total of 113 consecutive patients with newly diagnosed DLBCL who had undergone standard pretreatment evaluation, including serum lactate dehydrogenase measurement, Eastern Cooperative Oncology Group performance status assessment, computed tomography or (18)F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography, and BMB, were retrospectively included. National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) score and treatment strategy were determined in each patient, once without and once with taking into account BMB results. Numbers and percentages of BMB-induced changes on NCCN-IPI-based risk stratification (i.e. formation of low, low-intermediate, high-intermediate, and high risk groups) and choice of treatment were calculated, along with 95% confidence intervals (CIs). RESULTS: BMB was positive in 18 of 113 patients (15.9%, 95% CI 10.2-23.9 %). BMB-induced changes on NCCI-IPI-based risk stratification occurred in 9 of 113 patients (8.0%, 95% CI 4.1-14.6%). Five patients were upstaged from low-intermediate to high-intermediate risk, and four patients were upstaged from high-intermediate to high risk. BMB findings changed treatment planning in none of the 113 patients (0.0%, 95% CI 0.0-4.0%). CONCLUSION: Although BMB results upstaged the NCCN-IPI-based risk stratification in a small number of cases, this did not have any therapeutic implications in our patient series. These findings support the omission of BMB from routine staging of newly diagnosed DLBCL in the current risk stratification and treatment era.

Prognostic superiority of the National Comprehensive Cancer Network International Prognostic Index over pretreatment whole-body volumetric-metabolic FDG-PET/CT metrics in diffuse large B-cell lymphoma.

PURPOSE: This study aimed to determine the prognostic value of whole-body maximum standardized uptake value (SUVmax ), whole-body metabolic tumor volume (MTV), and whole-body total lesion glycolysis (TLG) at pretreatment (18) F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: Seventy-three patients with newly diagnosed DLBCL who had undergone FDG-PET/CT before rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisolone (R-CHOP) immunochemotherapy were retrospectively included. All FDG-avid lesions in each patient were segmented using semi-automated software to calculate whole-body SUVmax , whole-body MTV, and whole-body TLG values. Cox regression analyses were used to determine the associations of whole-body SUVmax , whole-body MTV, whole-body TLG, and dichotomized National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) risk group (low risk vs. high risk) with progression-free survival (PFS) and overall survival (OS). RESULTS: On univariate Cox regression analysis, only the NCCN-IPI was a significant predictor of PFS (P = 0.024), and only the NCCN-IPI and whole-body MTV were significant predictors of OS (P = 0.039 and P = 0.043, respectively). In the multivariate Cox proportional hazards model, only the NCCN-IPI remained an independent predictive factor of PFS (P = 0.024) and OS (P = 0.039). CONCLUSION: Whole-body SUVmax , whole-body MTV, and whole-body TLG do not provide any prognostic information in DLBCL beyond that which can already be obtained by the NCCN-IPI. Therefore, the NCCN-IPI remains the most important prognostic tool in this disease.

Direct comparison of visual and quantitative bone marrow FDG-PET/CT findings with bone marrow biopsy results in diffuse large B-cell lymphoma: does bone marrow FDG-PET/CT live up to its promise?

BACKGROUND: Detection of bone marrow involvement using 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) has been proposed as a non-invasive alternative to standard blind bone marrow biopsy (BMB) of the posterior iliac crest in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). However, studies that directly compare FDG-PET/CT results with histopathology are currently lacking. PURPOSE: To directly compare both visual and quantitative bone marrow FDG-PET/CT to BMB at the right posterior iliac crest in patients with newly diagnosed DLBCL. MATERIAL AND METHODS: A total of 40 patients with newly diagnosed DLBCL, who had undergone FDG-PET/CT before BMB of the right posterior iliac crest, were retrospectively included. FDG-PET/CT images were visually assessed for bone marrow involvement in the right posterior iliac crest. 3D partial volume corrected mean standardized uptake value (cSUVmean), maximum standardized uptake value (SUVmax), and peak standardized uptake value (SUVpeak) were measured in the right posterior iliac crest, using volume of interest analysis. BMB of the right posterior iliac crest was used as reference standard for bone marrow involvement. RESULTS: Sensitivity and specificity of visual FDG-PET/CT analysis for the detection of bone marrow involvement in the right posterior iliac crest were 14.3% (95% confidence interval [CI], 0.5-53.4%) and 100% (95% CI, 87.6-100%), respectively. cSUVmean, SUVmax, and SUVpeak of BMB-negative patients (1.4 ± 0.49, 2.2 ± 0.69, and 1.7 ± 0.59, respectively) considerably overlapped with those of BMB-positive patients (1.8 ± 0.53, 2.7 ± 0.71, and 2.2 ± 0.61, respectively). CONCLUSION: In a local, head-to-head comparison with BMB, the diagnostic value of both visual and quantitative FDG-PET/CT for the detection of bone marrow involvement is low in patients with newly diagnosed DLBCL.