SUVmax in FDG-PET at the biopsy site correlates with the proliferation potential of tumor cells in non-Hodgkin lymphoma

A PET-Surrogate Signature for the Interrogation of the Metabolic Status of Breast Cancers

Metabolic alterations in cancers can be exploited for diagnostic, prognostic, and therapeutic purposes. This is exemplified by 18F-fluorodeoxyglucose (FDG)-positron emission tomography (FDG-PET), an imaging tool that relies on enhanced glucose uptake by tumors for diagnosis and staging. By performing transcriptomic analysis of breast cancer (BC) samples from patients stratified by FDG-PET, a 54-gene signature (PETsign) is identified that recapitulates FDG uptake. PETsign is independently prognostic of clinical outcome in luminal BCs, the most common and heterogeneous BC molecular subtype, which requires improved stratification criteria to guide therapeutic decision-making. The prognostic power of PETsign is stable across independent BC cohorts and disease stages including the earliest BC stage, arguing that PETsign is an ab initio metabolic signature. Transcriptomic and metabolomic analysis of BC cells reveals that PETsign predicts enhanced glycolytic dependence and reduced reliance on fatty acid oxidation. Moreover, coamplification of PETsign genes occurs frequently in BC arguing for their causal role in pathogenesis. CXCL8 and EGFR signaling pathways feature strongly in PETsign, and their activation in BC cells causes a shift toward a glycolytic phenotype. Thus, PETsign serves as a molecular surrogate for FDG-PET that could inform clinical management strategies for BC patients.

Clinical Application of 18F-FDG-PET Quantification in Hematological Malignancies: Emphasizing Multiple Myeloma, Lymphoma and Chronic Lymphocytic Leukemia

Most hematological malignancies display heightened glycolytic activity, leading to their detectability through 18F-FDG-PET imaging. PET quantification enables the extraction of metabolic information from tumors. Among various PET measurements, maximum standardized uptake value (SUVmax), which indicates the highest value of 18F-FDG uptake within the tumor, has emerged as the commonly used parameter in clinical oncology. This is because of SUVmax ease of calculation using most available commercial workstations, as well as its simplicity and independence from observer interpretation. Nonetheless, SUVmax represents the increase in activity within a specific small area, which may not fully capture the overall tumor uptake. Volumetric PET parameters have been identified as a potential solution to overcome certain limitations associated with SUVmax. However, these parameters are influenced by the low spatial resolution of PET when assessing small lesions. Another challenge is the high number of lesions observed in some patients, leading to a time-consuming process for evaluating all focal lesions. Some institutions recently have started advocating for CT-based segmentation as a method for measuring radiotracer uptake in the bone marrow and overall bone of the patients. This review article aims to provide insights into clinical application of PET quantification specifically focusing on 3 major hematologic malignancies: multiple myeloma, lymphoma, and chronic lymphocytic leukemia.

Metabolic Positron Emission Tomography in Breast Cancer

Metabolic PET, most commonly 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT), has had a major impact on the imaging of breast cancer and can have important clinical applications in appropriate patients. While limited for screening, FDG PET/CT outperforms conventional imaging in locally advanced breast cancer. FDG PET/CT is more sensitive than conventional imaging in assessing treatment response, accurately predicting complete response or nonresponse in early-stage cases. It also aids in determining disease extent and treatment response in the metastatic setting. Further research, including randomized controlled trials with FDG and other metabolic agents such as fluciclovine, is needed for optimal breast cancer imaging.

Ki67 proliferation index in follicular lymphoma is associated with favorable outcome in patients treated with R-CHOP

Follicular lymphoma (FL) is a common, indolent small B-cell lymphoma. While the Follicular Lymphoma International Prognostic Index is widely used, reliable prognostic and predictive biomarkers are needed. A recent study suggested that architectural patterns of CD10, BCL6, and Ki67 expression may correlate with progression-free survival (PFS) in FL patients treated with chemotherapy-free regimens. We examined the prognostic and predictive utility of architectural patterns of CD10, BCL6, Ki67, and FOXP1 in 90 patients treated with immunochemotherapy (bendamustine-rituximab [BR] and R-cyclophosphamide, doxorubicin, vincristine, prednisone [CHOP]). We found that high follicular Ki67 (≥30%) was associated with longer PFS in the subgroup of patients treated with R-CHOP but not among those treated with BR. Validation of this biomarker may support routine use of Ki67 as a predictive marker in FL.

Differences in Tumour Aggressiveness Based on Molecular Subtype and Race Measured by [18F]FDG PET Metabolic Metrics in Patients with Invasive Carcinoma of the Breast

Breast cancer in women of African descent tends to be more aggressive with poorer prognosis. This is irrespective of the molecular subtype. [¹⁸F]FDG PET/CT metrics correlate with breast cancer aggressiveness based on molecular subtype. This study investigated the differences in [¹⁸F]FDG PET/CT metrics of locally advanced invasive ductal carcinoma (IDC) among different racial groups and molecular subtypes. Qualitative and semiquantitative readings of [¹⁸F]FDG PET/CT acquired in women with locally advanced IDC were performed. Biodata including self-identified racial grouping and histopathological data of the primary breast cancer were retrieved. Statistical analysis for differences in SUVmax, MTV and TLG of the primary tumour and the presence of regional and distant metastases was conducted based on molecular subtype and race. The primary tumour SUVmax, MTV, TLG and the prevalence of distant metastases were significantly higher in Black patients compared with other races (p < 0.05). The primary tumour SUVmax and presence of distant metastases in the luminal subtype and the primary tumour SUVmax and TLG in the basal subtype were significantly higher in Black patients compared with other races (p < 0.05). The significantly higher PET parameters in Black patients with IDC in general and in those with luminal and basal carcinoma subtypes suggest a more aggressive disease phenotype in this race.

The diagnosis and management of suspected lymphoma in general practice

With rapid advancements in diagnosis and treatment of malignancies, the gap between generalists and subspecialists continues to widen, particularly in cancers like lymphoma where the spectrum of disease varies from indolent to rapidly progressive. Prior to establishing with a hematologist/oncologist, patients must be accurately and comprehensively diagnosed and managed for lymphoma in the generalist setting. In the following manuscript, we review the common clinical presentations in which should raise concern for lymphoma. We summarize the literature regarding the role of laboratory studies including complete blood count and peripheral blood flow cytometry, the recommendations for lymph node sampling, the role and selection of imaging modalities, and ideal patient monitoring for high-risk clinical syndromes that may be encountered in lymphoma.

Laboratory Workup of Lymphoma in Adults: Guideline From the American Society for Clinical Pathology and the College of American Pathologists

CONTEXT.—

The diagnostic workup of lymphoma continues to evolve rapidly as experience and discovery led to the addition of new clinicopathologic entities and techniques to differentiate them. The optimal clinically effective, efficient, and cost-effective approach to diagnosis that is safe for patients can be elusive, in both community-based and academic practice. Studies suggest that there is variation in practice in both settings.

OBJECTIVE.—

To develop an evidence-based guideline for the preanalytic phase of testing, focusing on specimen requirements for the diagnostic evaluation of lymphoma.

DESIGN.—

The American Society for Clinical Pathology, the College of American Pathologists, and the American Society of Hematology convened a panel of experts in the laboratory workup of lymphoma to develop evidence-based recommendations. The panel conducted a systematic review of literature to address key questions. Using the Grading of Recommendations Assessment, Development, and Evaluation approach, recommendations were derived based on the available evidence, strength of that evidence, and key judgements as defined in the Grading of Recommendations Assessment, Development, and Evaluation Evidence to Decision framework.

RESULTS.—

Thirteen guideline statements were established to optimize specimen selection, ancillary diagnostic testing, and appropriate follow-up for safe and accurate diagnosis of indolent and aggressive lymphoma.

CONCLUSIONS.—

Primary diagnosis and classification of lymphoma can be achieved with a variety of specimens. Application of the recommendations can guide decisions on specimen suitability, diagnostic capabilities, and correct use of ancillary testing. Disease prevalence in patient populations, availability of ancillary testing, and diagnostic goals should be incorporated into algorithms tailored to each practice environment.

Laboratory Workup of Lymphoma in Adults

OBJECTIVES

The diagnostic workup of lymphoma continues to evolve rapidly as experience and discovery lead to the addition of new clinicopathologic entities and techniques to differentiate them. The optimal clinically effective, efficient, and cost-effective approach to diagnosis that is safe for patients can be elusive, in both community-based and academic practice. Studies suggest that there is variation in practice in both settings.

THE AIM OF THIS REVIEW IS TO

develop an evidence-based guideline for the preanalytic phase of testing, focusing on specimen requirements for the diagnostic evaluation of lymphoma.

METHODS

The American Society for Clinical Pathology, the College of American Pathologists, and the American Society of Hematology convened a panel of experts in the laboratory workup of lymphoma to develop evidence-based recommendations. The panel conducted a systematic review of the literature to address key questions. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, recommendations were derived based on the available evidence, the strength of that evidence, and key judgments as defined in the GRADE Evidence to Decision framework.

RESULTS

Thirteen guideline statements were established to optimize specimen selection, ancillary diagnostic testing, and appropriate follow-up for safe and accurate diagnosis of indolent and aggressive lymphoma.

CONCLUSIONS

Primary diagnosis and classification of lymphoma can be achieved with a variety of specimens. Application of the recommendations can guide decisions about specimen suitability, diagnostic capabilities, and correct utilization of ancillary testing. Disease prevalence in patient populations, availability of ancillary testing, and diagnostic goals should be incorporated into algorithms tailored to each practice environment.

Correlations between maximum standardized uptake value measured via 18F-fluorodeoxyglucose positron emission tomography/computed tomography and clinical variables and biochemical indicators in adult lymphoma

Objectives

The aim of the current study was to investigate whether the maximum standardized uptake value (SUVmax) measured by ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) could discriminate between aggressive and indolent non-Hodgkin lymphomas (NHLs) and correlations between the SUVmax and clinical variables and serum biochemical indicators in adult lymphoma.

Methods

A total of 103 patients with lymphoma confirmed by biopsy, pretreatment ¹⁸F-FDG PET/CT scans, and a complete medical record were retrospectively enrolled in the study. Clinical variables that were evaluated included stage, pathological subtype, International Prognostic Index (IPI) score, and Ki-67 index, as well as serum biochemical indicators (e.g., lactate dehydrogenase [LDH] and erythrocyte sedimentation rate [ESR]) and metabolic parameters (e.g., SUVmax of the biopsy site on PET/CT). Correlations between SUVmax and clinical variables and serum biochemical indicators were investigated.

Results

Of the 103 patients, 84 had NHL and 19 had Hodgkin lymphoma. The area under the receiver operating characteristic curve for examining the accuracy of SUVmax with regard to distinguishing between aggressive and indolent NHLs was 0.94 (95% confidence interval: 0.89-0.99), suggesting that SUVmax was a useful predictor of diagnosis. A cutoff value of 8.5 yielded a sensitivity of 76.3% and specificity of 92.0%. The SUVmax mean ± standard deviation of NHL (9.8 ± 6.0, range: 1.8-28.1) was higher than that of HL (7.5 ± 2.8, range: 3.5-13.9) (P = 0.016), but there was no statistically significant difference in SUVmax between NHL and HL (P > 0.05). SUVmax of the biopsy site was strongly positively correlated with Ki-67 index (r = 0.813, P < 0.001) and moderately positively correlated with IPI score (r = 0.332, P = 0.002), but it was not significantly correlated with clinical stage, LDH, or ESR (P > 0.05).

Conclusions

¹⁸F-FDG PET/CT may yield reliable measurements of tumor proliferation, and an SUVmax >8.5 may distinguish between aggressive and indolent NHLs. In adults with newly diagnosed lymphoma, SUVmax correlates with Ki-67 index and IPI score.

PET-CT imaging features that differentiate between positive and negative EWSR1 translocation in Ewing sarcoma

OBJECTIVES

Ewing sarcoma breakpoint region 1 (EWSR1) translocation-negative tumors represent a minor portion of small round cell tumors consistent with Ewing sarcoma morphology. The purpose of this study was to differentiate EWSR1 translocation-positive tumors from EWSR1 translocation-negative tumors using PET-computed tomography features.

MATERIALS AND METHODS

In this retrospective study 27, Ewing sarcoma patients (December 2011 to November 2016) were divided into two groups, EWSR1 translocation-positive and EWSR1 translocation-negative based on cytogenetic analysis. Pretreatment standardized uptake value maximum (SUVmax) and Hounsfield Units (HU) were measured in the primary tumor in the axial slice with the largest tumor diameter.The associations between SUVmax, HU and the presence of EWSR1 translocation were evaluated. Receiver operating characteristic curve analysis was used to determine cut-off levels of SUVmax and HU suggestive of EWSR1-negative tumors.

RESULTS

Twenty-one patients were classified as EWSR1-positive and six as EWSR1-negative. Eighteen had SUVmax and 21 had HU measurements. EWSR1-negative tumors had significantly higher SUVmax values (P = 0.003) and significantly lower HU values (P = 0.008). Receiver operating characteristic curve analysis showed that SUVmax had diagnostic ability to discriminate between EWSR1-negative and EWSR1-positive tumors (area under the curve = 0.964, P = 0.006). A SUVmax of at least 10 had a sensitivity of 100% and specificity of 85.7% for EWSR1-negative tumors. HU had lower diagnostic ability than SUVmax (area under the curve = 0.881, P = 0.012). A HU up to 57 had a sensitivity of 81.3% and specificity of 80.0% for EWSR1-negative tumors.

CONCLUSION

Higher SUVmax and lower HU may differentiate between EWSR1-positive and EWSR1-negative tumors. This may reflect EWSR1-negative tumor aggressiveness.

Correlations Between Imaging Biomarkers and Proliferation Index Ki-67 in Lymphomas: A Systematic Review and Meta-Analysis

BACKGROUND

Few studies investigated relationships between positron emission tomography (PET) as well as diffusion-weighted imaging (DWI) with proliferating index Ki-67 in lymphomas. The aim of the present analysis was to review the published results and perform a meta-analysis to provide data on the associations between standardized uptake values (SUV) derived from PET as well as apparent diffusion coefficient (ADC) derived from DWI with Ki-67 index in lymphomas.

MATERIALS AND METHODS

The MEDLINE library was screened for relationships between PET and DWI with Ki-67 in lymphoma up to October 2018. Overall, 22 studies with 788 patients were identified. The following data were extracted from the literature: authors, year of publication, number of patients, and correlation coefficients. Associations between SUV and Ki-67 were analyzed using Spearman correlation coefficient.

RESULTS

Fifteen studies comprising 574 patients were suitable for the analysis between maximum SUV (SUV_max) derived from fluorodeoxyglucose (FDG) PET and Ki-67. The pooled correlation coefficient was r = 0.49 (95% confidence interval [CI], 0.36-0.61). Four studies were included in the analysis between SUV_max derived from fluorothymidine (FLT) PET and Ki-67 index involving 84 patients. The pooled correlation coefficient was r = 0.46 (95% CI, 0.19-0.73). Four studies comprising 130 patients were suitable for the analysis between ADC values derived from DWI and Ki-67. The pooled correlation coefficient was r = -0.25 (95% CI, -0.53 to 0.04).

CONCLUSION

SUV_max derived from FDG and FLT PET correlated moderately and approximately equally with Ki-67 index. On the contrary, ADC values only correlated weakly inversely and might not reliably predict Ki-67 index in lymphomas.

Volume-based parameters on FDG PET may predict the proliferative potential of soft-tissue sarcomas

INTRODUCTION

Soft-tissue sarcomas (STS) are rare types of tumors that have variable levels of tumor differentiation. F-18 fluorodeoxyglucose positron emission tomography (FDG PET) has been established as an useful tool for STS patients, and the metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are reported to be useful in various cancers. We compared the diagnostic value of four PET parameters (maximum standardized uptake value [SUVmax], SUVmean, MTV, and TLG) from two acquisition timings for predicting the expression of the pathological marker of cell proliferation Ki-67, based on pathological investigation.

MATERIALS AND METHODS

In this retrospective study, we investigated 20 patients (59 ± 19 years old, 18-87 years old) with pathologically confirmed STS who underwent FDG PET before surgical intervention. The patients fasted ≥ 6 h before the intravenous injection of FDG. The whole body was scanned twice; at an early phase (61.5 ± 2.6 min) and at a delayed phase (118.0 ± 2.1 min) post-injection. The SUVmax, SUVmean, MTV, and TLG of the primary lesion were measured with a tumor boundary determined by SUV ≥ 2.0. Ki-67 was measured using MIB-1 immunohistochemistry. We used Pearson's correlation coefficient to analyze the relationships between the PET parameters and Ki-67 expressions. The Kaplan-Meier analysis with the log-rank test was performed to compare overall survival between high-group and low-group at each of the four PET parameters and Ki-67 expression.

RESULTS

All four PET parameters at each phase showed significant correlations with Ki-67. Among them, the Pearson's correlation coefficient (r) was largest for TLG (r = 0.76 and 0.77 at the early and delayed phases, respectively), followed by MTV (0.70 and 0.72), SUVmax (r = 0.65 and 0.66), and SUVmean (r = 0.62 and r = 0.64). From early to delayed phases, the SUVmax and SUVmean both increased in all 20 patients, whereas the MTV and TLG increased in 13/20 (65%) and 16/20 (80%) patients, respectively. None of the %increases of the PET parameters were significantly correlated with Ki-67. The overall survival was shorter for high-SUVmax, high-SUVmean, high-TLG, and high-Ki-67 groups than the other groups, although the difference did not reach statistical significance.

CONCLUSION

The SUVmax, SUVmean, MTV, and TLG acquired at both 1 and 2 h after injection showed significant correlations with Ki-67. Among them, correlation coefficient with Ki-67 expression was highest for TLG, although the best parameter should be determined in a larger population. The delayed-phase FDG PET was equally useful as that of early-phase to predict tumor aggressiveness in STS.

Ultra-early response assessment in lymphoma treatment: [18F]FDG PET/MR captures changes in glucose metabolism and cell density within the first 72 hours of treatment

PURPOSE

To determine whether, in patients with Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL), [18F]FDG PET/MR can capture treatment effects within the first week after treatment initiation, and whether changes in glucose metabolism and cell density occur simultaneously.

METHODS

Patients with histologically proven HL or NHL were included in this prospective IRB-approved study. Patients underwent [18F]FDG PET/MR before, and then 48-72 h after (follow-up 1, FU-1) and 1 week after (FU-2) initiation of the first cycle of their respective standard chemotherapy (for HL) or immunochemotherapy (for NHL). Standardized [18F]FDG uptake values (SUVmax, SUVmean) and apparent diffusion coefficients (ADCmin, ADCmean) based on diffusion-weighted MRI, and metabolic and morphological tumour volumes (MTV, VOL) were assessed at each time-point. Multilevel analyses with an unstructured covariance matrix, and pair-wise post-hoc tests were used to test for significant changes in SUVs, ADCs, MTVs and VOLs between the three time-points.

RESULTS

A total of 58 patients (11 with HL and 47 with NHL) with 166 lesions were analysed. Lesion-based mean rates of change in SUVmax, SUVmean, ADCmin, ADCmean, MTV and VOL between baseline and FU-1 were -46.8%, -33.3%, +20.3%, +14%, -46% and -12.8%, respectively, and between baseline and FU-2 were -65.1%, -49%, +50.7%, +32.4%, -61.1% and -24.2%, respectively. These changes were statistically significant (P < 0.01) except for the change in VOL between baseline and FU-1 (P = 0.079).

CONCLUSION

In lymphoma patients, [18F]FDG PET/MR can capture treatment-induced changes in glucose metabolism and cell density as early as 48-72 h after treatment initiation.

Tumor and bone marrow uptakes on [18F]fluorodeoxyglucose positron emission tomography/computed tomography predict prognosis in patients with diffuse large B-cell lymphoma receiving rituximab-containing chemotherapy

The purpose of this study was to determine the relevance of standardized uptake value (SUV) on [F]fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), focusing on tumor and bone marrow, to disease outcomes based on progression-free survival (PFS) and overall survival (OS) in patients with diffuse large B-cell lymphoma (DLBCL) receiving rituximab-containing chemotherapy.We reviewed the records of patients with DLBCL who were diagnosed between September 2009 and January 2013 and underwent pretreatment whole-body FDG PET/CT scans. All patients received rituximab-containing chemotherapy. The maximal SUV of tumor (SUVt) and maximal SUV of sternum (SUVst) were measured. Univariate and multivariate analyses were used to assess the prognostic significance of SUVt, SUVst, gender, age, clinical stage, international prognostic index (IPI), and laboratory tests.There were total 70 patients enrolled in this study. The median follow-up time was 36 months. An SUVt cut-off value of ≥19 had the best discriminative yield for PFS (P = .04). An SUVst cut-off value of ≥1.6 had the best discriminative yield for OS. The 3-year OS rates for patients with maximal SUVst < 1.6 and for those with maximal SUVst ≥1.6 were 74.8% and 57.1%, respectively (P = .04). Further forward, multivariate Cox proportional hazards model revealed that maximal SUVst (hazard ratio: 2.62; 95% confidence interval: 1.10-6.28; P = .03) and IPI were significant factors affecting OS.In patients with DLBCL receiving rituximab-containing chemotherapy, elevated maximal SUVt ≥19 was an independent predictor for shorter PFS, and maximal SUVst ≥1.6 was an independent predictor for shorter OS. It adds the value of pretreatment FDG PET/CT scans.

18F-FDG PET/CT in the clinical management of patients with lymphoma

The aim of this work was to review the current recommendations for staging and response assessment of patients with Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) in routine clinical practice after chemotherapy and/or stem cell transplantation. A five-point scale (5-PS) from the First International Workshop on PET in Lymphoma in Deauville, France, in 2009, was recommended as the standard tool to score imaging to assess treatment response in patients with lymphoma using ¹⁸F-Fluorodeoxyglucose (FDG) PET/CT. Following the recommendations of the 11th and 12th International Conferences on Malignant Lymphoma held in Lugano (Switzerland), in 2011 and 2013, respectively, a consensus (the so-called Lugano Classification) was reached regarding the use of PET/CT for staging and response assessment in FDG-avid lymphomas. As a result, ¹⁸F-FDG PET/CT was formally incorporated into standard staging for FDG-avid lymphomas. A bone marrow biopsy is no longer indicated for the routine staging of HL and most diffuse large B-cell lymphomas. PET/CT will be used to assess response in FDG-avid histologies using the 5-point scale. The recent introduction of biological agents with immune mechanisms requires flexibility in interpretations of the Lugano criteria due to tumour flare or a pseudo-progression effect produced by these agents. Provisional criteria have been proposed (Lymphoma Response to Immunomodulatory Therapy Criteria) with the introduction of the term 'Indeterminate Response' in order to identify this phenomenon until confirmed as flare/pseudoprogression or true progression. All these recommendations will improve evaluations of patients with lymphoma, and allow comparison of results from clinical practice and trials.

Complete metabolic response (CMR) in positron emission tomography-computed tomography (PET-CT) scans may have prognostic significance in patients with marginal zone lymphomas (MZL)

Although clinical use of positron emission tomography-computed tomography (PET-CT) scans is well established in aggressive lymphomas, its prognostic value in marginal zone lymphoma (MZL) remains yet unclear. Hence, we investigated potential role of PET-CT in predicting MZL patients' outcomes following systemic chemotherapy. A total of 32 patients with MZL who received first-line chemotherapy were included in the analysis. They all underwent pretreatment, interim, and posttreatment PET-CT scans. The primary objective was to evaluate the role of complete metabolic response (CMR) in posttreatment PET-CT scans in predicting progression-free survival (PFS). Compared with non-CMR group, 5-year PFS rate was significantly higher in patients who achieved CMR in posttreatment PET-CT (54.2% vs 0.0%, P = .003) and also in patients gaining CMR in interim PET-CT scans (62.5% vs 15.6%, P = .026). Interestingly, early CMR group, who achieved and maintained CMR in both interim and posttreatment PET-CT scans, showed significantly higher 5-year PFS than those with delayed or never CMR group (62.5% vs 37.5% vs 0%, P = .008). Therefore, interim and/or posttreatment CMR can be prognostic at least in these subsets of patients with MZL treated with chemotherapy.

Correlation of pretreatment 18F-FDG uptake with clinicopathological factors and prognosis in patients with newly diagnosed diffuse large B-cell lymphoma

Supplemental Digital Content is available in the text.

Objectives

The aim of this study is to determine the correlation of pretreatment fluorine-18 fluorodeoxyglucose uptake with clinicopathological factors and its prognostic value in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL).

Patients and methods

A cohort of 162 patients with newly diagnosed DLBCL who had undergone pretreatment PET/computed tomography was retrospectively reviewed. The relationship of pretreatment maximum standard uptake value (SUV_max) with clinical factors, molecular markers, and efficacy was evaluated. The value of SUV_max in predicting progression-free survival (PFS) and overall survival was analyzed.

Results

In all, 72.9% of the patients received R-CHOP treatment; the rest received CHOP chemotherapy. The median follow-up duration was 30 months (range, 4–124 months). The median SUV_max was 12.2 (range, 1.7–42.7). SUV_max between groups differed significantly with respect to each of International Prognostic Index (IPI) factors, except for age and performance status. High SUV_max was associated with high Ki-67 and Glut-3 protein expression, but not with Glut-1. Complete remission rate differed significantly between the low (SUV_max≤9.0) and the high SUV_max (SUV_max>9.0) groups (91.7 vs. 61.1%, P=0.000). Patients with low SUV_max showed favorable survival (3-year PFS: 92.2 vs. 63.6%, P=0.000; 3-year overall survival: 95.5 vs. 78.3%, P=0.003). On multivariate analyses, SUV_max predicted PFS independent of revised-IPI (SUV_max: P=0.011, hazard ratio 4.784; revised-IPI: P=0.004, hazard ratio 2.551).

Conclusion

Pretreatment SUV_max was associated with clinicopathological factors, efficacy, and survival outcome. A novel prognostic model on the basis of IPI score/pretreatment SUV_max might be useful for risk stratification of patients with newly diagnosed DLBCL Video abstract: http://links.lww.com/NMC/A55.

Secreted frizzled-related protein 1 overexpression in gastric cancer: Relationship with radiological findings of dual-energy spectral CT and PET-CT

We explored the role of secreted frizzled-related protein 1 (sFRP1) overexpression in gastric cancer and its relationship with radiological findings from dual-energy spectral CT(DEsCT) and positron emission tomography/computed tomography (PET/CT). We established mouse metastatic models using the SGC-7901/sFRP1 gastric cancer cell line. A control group was established using the SGC-7901/vector cell line. The models were then scanned with dual-energy spectral CT and PET-CT. Subsequent analysis, including immunohistochemistry and Transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL), was performed to confirm the role of sFRP1. Transwell chamber and angiogenesis assays were conducted to verify the effect of sFRP1 in vitro. We found that the control group showed negative radiological performance with successful implantation. Concurrently, the treated group showed visible lesions, a higher FDG uptake and increasing enhancement. The immunological and histological analysis confirmed the positive radiological performance with larger size, increasing proliferation, more microvessels and less apoptosis. The angiogenic up-regulation of sFRP1 overexpression were further verified with in vitro cell models. This preliminary study demonstrates that sFRP1 overexpression in gastric cancer cells leads to increased cell proliferation and angiogenesis, which may, in turn, contribute to positive PET/CT and CT performances.

Advancing Precision Nuclear Medicine and Molecular Imaging for Lymphoma

PET with fluorodeoxyglucose F 18 (¹⁸F FDG-PET) is a meaningful biomarker for the detection, targeted biopsy, and treatment of lymphoma. This article reviews the evolution of ¹⁸F FDG-PET as a putative biomarker for lymphoma and addresses the current capabilities, challenges, and opportunities to enable precision medicine practices for lymphoma. Precision nuclear medicine is driven by new imaging technologies and methodologies to more accurately detect malignant disease. Although quantitative assessment of response is limited, such technologies will enable a more precise metabolic mapping with much higher definition image detail and thus may make it a robust and valid quantitative response assessment methodology.

FDG-PET imaging in hematological malignancies

The majority of aggressive lymphomas is characterized by an up regulated glycolytic activity, which enables the visualization by F-18 FDG-PET/CT. One-stop hybrid FDG-PET/CT combines the functional and morphologic information, outperforming both, CT and FDG-PET as separate imaging modalities. This has resulted in several recommendations using FDG-PET/CT for staging, restaging, monitoring during therapy, and assessment of treatment response as well as identification of malignant transformation. FDG-PET/CT may obviate the need for a bone marrow biopsy in patients with Hodgkin's lymphoma and diffuse large B cell lymphoma. FDG-PET/CT response assessment is recommended for FDG-avid lymphomas, whereas CT-based response evaluation remains important in lymphomas with low or variable FDG avidity. The treatment induced change in metabolic activity allows for assessment of response after completion of therapy as well as prediction of outcome early during therapy. The five-point scale Deauville Criteria allows the assessment of treatment response based on visual FDG-PET analysis. Although the use of FDG-PET/CT for prediction of therapeutic response is promising it should only be conducted in the context of clinical trials. Surveillance FDG-PET/CT after complete remission is discouraged due to the relative high number of false-positive findings, which in turn may result in further unnecessary investigations. Future directions include the use of new PET tracers such as F-18 fluorothymidine (FLT), a surrogate biomarker of cellular proliferation and Ga-68 CXCR4, a chemokine receptor imaging biomarker as well as innovative digital PET/CT and PET/MRI techniques.

Basal (18)F-FDG PET/CT in follicular lymphoma: A comparison of metabolic and clinical variables in the prognostic assessment

AIM

To analyze the relationship of clinical variables related to prognosis and tumor burden, with metabolic variables obtained in the staging (18)F-FDG PET/CT, and their value in the prognosis in follicular lymphoma (FL).

METHODS

82 patients with FL, a (18)F-FDG PET/CT at diagnosis and a follow-up for a minimum of 12 months, were retrospectively enrolled in the present study. Clinical variables (Tumor grade, Follicular Lymphoma International Prognostic Index (FLIPI) and Tumor burden) were evaluated. Metabolic variables such as SUVmax in the highest hypermetabolic lesion, extralymphatic locations, number of involved lymph node locations, bone marrow (BM) involvement, PET stage and diameter of the biggest hypermetabolic lesion, were analyzed in order to establish a PET score and classify the studies in low, intermediate and high metabolic risk. Clinical and metabolic variables (included metabolic risk) were compared. The relation among all variables and disease-free survival (DFS) was studied.

RESULTS

The 28% of patients had a high-grade tumor. The 30.5% had FLIPI risk low, 29.3% intermediate y 40.2% high. The 42.7% presented a high tumor burden. The PET/CT was positive in 94% of patients. The tumor grade did not show significant relation with metabolic variable. FLIPI risk and tumor burden showed statistical relations with the SUV max and the PET score (p<0.008 and p=0.003 respectively). With respect to DFS, significant differences were detected for the PET stage and FLIPI risk (p=0.015 and p=0.047 respectively). FLIPI risk was the only significant predictor in Cox regression analysis, with a Hazard Ratio of 5.13 between high risk and low risk.

CONCLUSION

The present research highlights the significant relation between metabolic variables obtained with FDG PET/CT and clinical variables although their goal as an independent factor of prognosis was not demonstrated in the present work.

PET-CT in the UK: current status and future directions

Combined positron-emission tomography and computed tomography (PET-CT) has taken the oncological world by storm since being introduced into the clinical domain in the early 21(st) century and is firmly established in the management pathway of many different tumour types. Non-oncological applications of PET-CT represent a smaller but steadily growing area of interest. PET-CT continues to be the focus of a large number of research studies and keeping up-to-date with the literature is important but represents a challenge. Consequently guidelines recommending PET-CT usage need to be revised regularly to encompass new developments. The purpose of this article is twofold: first, it provides a detailed review of the evidence-base underpinning the major uses of PET-CT in clinical practice, which may be of value to a wide-range of individuals, including those directly involved with PET-CT and to a much larger group with limited exposure, but for whom a précis of the current state-of-play may help inform other radiology and multidisciplinary team (MDT) work; the second purpose is as a companion to revised guidelines on evidence-based indications for PET-CT in the UK (being published concurrently) providing a detailed commentary on new indications with a summary of emerging data supporting these additional clinical uses of the technique.

Malignant cardiac tumors: diagnosis and treatment

Primary malignant cardiac tumors are represented by sarcomas and non-Hodgkin lymphomas. They are rare, affect mostly patients in the fourth decade of life and have a severe prognosis. Both the diagnosis and the treatment require a multidisciplinary approach, and the cardiologist plays a central role both in the diagnosis and in the follow-up. The prognosis may be improved by a careful planning of surgery and by the use of multimodality treatment, including complementary chemotherapy and radiation therapy. A strict follow-up must be planned even after apparently complete cure.

Correlation between the Uptake of 18F-Fluorodeoxyglucose (18F-FDG) and the Expression of Proliferation-Associated Antigen Ki-67 in Cancer Patients: A Meta-Analysis

Objective

To study the correlation between ¹⁸F-FDG uptake and cell proliferation in cancer patients by meta-analysis of published articles.

Methods

We searched PubMed (MEDLINE included), EMBASE, and Cochrane Database of Systematic Review, and selected research articles on the relationship between ¹⁸F-FDG uptake and Ki-67 expression (published between August 1, 1994-August 1, 2014), according to the literature inclusion and exclusion criteria. The publishing language was limited to English. The quality of included articles was evaluated according to the Quality Assessment of Diagnosis Accuracy Studies-2 (QUADAS-2). The correlation coefficient (r) was extracted from the included articles and processed by Fisher's r-to-z transformation. The combined correlation coefficient (r) and the 95% confidence interval (CI) were calculated with STATA 11.0 software under a random-effects model. Begg's test was used to analyze the existence of publication bias and draw funnel plot, and the sources of heterogeneity were explored by sensitivity and subgroup analyses.

Results

According to the inclusion and exclusion criteria, 79 articles were finally included, including 81 studies involving a total of 3242 patients. All the studies had a combined r of 0.44 (95% CI, 0.41-0.46), but with a significant heterogeneity (I² = 80.9%, P<0.01). Subgroup analysis for different tumor types indicated that most subgroups showed a reduced heterogeneity. Malignant melanoma (n = 1) had the minimum correlation coefficient (-0.22) between ¹⁸F-FDG uptake and Ki-67 expression, while the thymic epithelial tumors (TETs; n = 2) showed the maximum correlation coefficient of 0.81. The analytical results confirmed that correlation between ¹⁸F-FDG uptake and Ki-67 expression was extremely significant in TETs, significant in gastrointestinal stromal tumors (GISTs), moderate in patients with lung, breast, bone and soft tissue, pancreatic, oral, thoracic, and uterine and ovarian cancers, average in brain, esophageal and colorectal cancers, and poor in head and neck, thyroid, gastric and malignant melanoma tumors. Subgroup analysis indicated that positron emission tomography (PET) or PET/CT imaging technology or Ki-67 and standardized uptake value (SUV) measurement technology did not significantly affect the results of r values, and Begg's test showed no significant publication bias.

Conclusion

In cancer patients, ¹⁸F-FDG uptake showed a moderate positive correlation with tumor cell proliferation. Different tumor types exhibited varied degree of correlation, and the correlation was significant in TETs and GSTs. However, our results need further validation by clinical trials with a large sample of different tumor types.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Evaluation of Diffusion-Weighted Magnetic Resonance Imaging for Follow-up and Treatment Response Assessment of Lymphoma: Results of an 18F-FDG-PET/CT–Controlled Prospective Study in 64 Patients

Purpose: To determine the value of diffusion-weighted MRI (DWI-MRI) for treatment response assessment in 2-[18F]fluoro-2-deoxy-D-glucose (FDG)–avid lymphoma.

Experimental Design: Patients with FDG-avid Hodgkin (HL) or non-Hodgkin lymphoma (NHL) at pretherapeutic 18F-FDG-PET/CT, who had also undergone pretherapeutic whole-body DWI-MRI, were included in this prospective study. Depending on the histologic lymphoma subtype, patients received different systemic treatment regimens, and follow-up DWI-MRI and 18F-FDG-PET/CT were performed at one or more time points, depending on the clinical course. For each follow-up DWI-MRI, region-based rates of agreement, and rates of agreement in terms of treatment response (complete remission, partial remission, stable disease, or progressive disease), relative to the corresponding 18F-FDG-PET/CT, were calculated.

Results: Sixty-four patients were included: 10 with HL, 22 with aggressive NHL, and 32 with indolent NHL. The overall region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.4%. For the 51 interim examinations (performed after 1–3 therapy cycles), region-based agreement of DWI-MRI with 18F-FDG-PET/CT was 99.2%, and for the 48 end-of-treatment examinations, agreement was 99.8%. No significant differences, in terms of region-based agreement between DWI-MRI and 18F-FDG-PET/CT, were observed between the three lymphoma groups (HL, aggressive NHL, indolent NHL; P = 0.25), or between interim and end-of-treatment examinations (P = 0.21). With regard to treatment response assessment, DWI-MRI agreed with 18F-FDG-PET/CT in 99 of 102 follow-up examinations (97.1%), with a κ value of 0.94 (P &lt; 0.0001).

Conclusions: In patients with FDG-avid lymphoma, DWI-MRI may be a feasible alternative to 18F-FDG-PET/CT for follow-up and treatment response assessment. Clin Cancer Res; 21(11); 2506–13. ©2015 AACR.

Role of imaging in the staging and response assessment of lymphoma: consensus of the International Conference on Malignant Lymphomas Imaging Working Group

PURPOSE

Recent advances in imaging, use of prognostic indices, and molecular profiling techniques have the potential to improve disease characterization and outcomes in lymphoma. International trials are under way to test image-based response–adapted treatment guided by early interim positron emission tomography (PET)–computed tomography (CT). Progress in imaging is influencing trial design and affecting clinical practice. In particular, a five-point scale to grade response using PET-CT, which can be adapted to suit requirements for early- and late-response assessment with good interobserver agreement, is becoming widely used both in practice- and response-adapted trials. A workshop held at the 11th International Conference on Malignant Lymphomas (ICML) in 2011 concluded that revision to current staging and response criteria was timely.

METHODS

An imaging working group composed of representatives from major international cooperative groups was asked to review the literature, share knowledge about research in progress, and identify key areas for research pertaining to imaging and lymphoma.

RESULTS

A working paper was circulated for comment and presented at the Fourth International Workshop on PET in Lymphoma in Menton, France, and the 12th ICML in Lugano, Switzerland, to update the International Harmonisation Project guidance regarding PET. Recommendations were made to optimize the use of PET-CT in staging and response assessment of lymphoma, including qualitative and quantitative methods.

CONCLUSION

This article comprises the consensus reached to update guidance on the use of PET-CT for staging and response assessment for [18F]fluorodeoxyglucose-avid lymphomas in clinical practice and late-phase trials.

Extranodal lymphoma originating in the gluteal muscle with adjacent bone involvement and mimicking a soft tissue sarcoma

Introduction

Extranodal lymphoma (ENL) in the muscles is a rare manifestation of non-Hodgkin lymphoma (NHL). The aim of this case report is to describe and evaluate the clinical presentation and important radiologic features of ENL affecting the musculoskeletal system.

Presentation of case

We present a 52-year-old female with a 3-week history of left gluteal pain. Computed tomography (CT) showed a non-uniformly early enhancing mass in the left gluteal muscle, the tumor demonstrating central necrosis and adjacent bone involvement. Fluorine-18 fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT showed areas of increased ¹⁸F-FDG uptake in the left gluteal musculature, pelvic bones, para-aortic and mediastinal lymph nodes and both lungs. Histopathological examination showed a diffuse large B cell lymphoma (DLBCL). After 8 cycles of R-CHOP chemotherapy, the mass in the left gluteal muscle has completely disappeared

Discussion

Although destructive tumor originating in the gluteal muscle with adjacent bone involvement is more common in soft tissue sarcoma, lymphoma should be regularly included in the differential diagnosis. While CT is a useful modality for assessing soft tissue masses, disruption and injury of the surrounding tissues, PET/CT fusion is superior for the detection of unexpected extranodal sites of disease, or for exclusion of disease in the presence of nonspecific extranodal CT findings.

Conclusion

A rapid growth pattern and destructive masses that invade adjacent structures on CT are key findings of DLBCL, and ¹⁸F-FDG PET/CT is a useful imaging modality to accurately determine the disease stage and disease aggressiveness of NHL.

A high-fat diet is associated with altered adipokine production and a more aggressive esophageal adenocarcinoma phenotype in vivo

OBJECTIVE

Obesity has been linked to esophageal adenocarcinoma (EAC). We hypothesize that adipokines, which are altered by obesity, could affect EAC growth rates and potentially serve as biomarkers of disease and targets for treatment. We have developed a potential murine model to investigate the effects of obesity-altered adipokines on EAC in vivo.

METHODS

Severe combined immune-deficient mice were fed either a high-fat diet (HFD) containing 60% animal fat, or a control diet with 10% animal fat, and monitored for weight gain for 5 weeks. All mice were subcutaneously implanted with EAC cells (OE33), and tumor volume was monitored for an additional 4 weeks by direct measurement and uptake of fluorescently labeled 2-D-deoxyglucose. At sacrifice, serum triglyceride levels and abdominal fat-pad weight were measured to assess obesity state. Adipokine levels were measured within abdominal fat of tumor-bearing mice.

RESULTS

Mice fed the HFD displayed increased body weight, visceral fat, and serum leptin and triglycerides. All mice developed tumors; OE33 EAC cells in HFD mice displayed increased growth rates, proliferation, and metabolic activity relative to tumors of EAC in control diet mice. Adipokine expression in the abdominal fat revealed distinct changes associated with the HFD and increased body weight.

CONCLUSIONS

Ad libitum feeding of the HFD was correlated with more-proliferative EAC tumors in vivo. This phenotype was associated with alterations to secreted adipokines, representing a potential mechanism for our observations. Further studies are necessary to explore findings, as they have potential to improve treatment of EAC.

Early interim PET/CT predicts post-treatment response in diffuse large B-cell lymphoma

BACKGROUND

(18)F-FDG-PET/CT has been widely used in the staging of malignant lymphomas, and accepted as a tool for response assessment. Among PET parameters, the most frequently studied is maximal standardized uptake value (SUVmax). Metabolic tumor burden (MTB) is a parameter in which both metabolic tumor volume (MTV) and tumor activity are integrated. Here, we analyzed the prognostic value of SUVmax, SUVsum (sum of the SUVmax), whole-body MTV (MTVwb) and MTBwb from baseline and interim PET/CT in patients with diffuse large B-cell lymphoma (DLBCL).

MATERIAL AND METHODS

Twenty-nine patients with histologically proven DLBCL were imaged by PET/CT before treatment (Exam I), and one week after the first dose of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) therapy (Exam II). Biopsy specimens were examined by an expert hematopathologist, the Ki-67 proliferation index (PI) was estimated for each biopsy site from the MIB-1 stained sections. The response evaluation was performed after chemotherapy completion (6-8 cycles).

RESULTS

All patients had one or more visualized lymphomatous lesions on (18)F-FDG-PET/CT. The SUVmax of the whole-body (BmSUVmax) was higher than the SUVmax at biopsy site (BxSUVmax) (mean: 20.1 vs. 17.3, p < 0.01). The PI correlated with the BxSUVmax (p < 0.05). One week after chemotherapy, SUVmax, SUVsum, MTVwb, and MTBwb decreased significantly (p < 0.01, respectively), SUVsum, MTVwb and MTBwb at Exam II correlated with chemotherapy response at treatment completion (p < 0.05, respectively).

CONCLUSION

SUVmax is more accurate to detect tumor aggressiveness than biopsy in DLBCL, since BmSUVmax represents the most aggressive tumor of the patient. Interim PET/CT as early as one week after R-CHOP therapy predicts response. Thus, it could be used as a tool for guidance of risk stratification in DLBCL.

F-18 FDG PET/CT quantization parameters as predictors of outcome in patients with diffuse large B-cell lymphoma

AIM

We evaluated the prognostic significance of standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) obtained by F-18 FDG PET/CT (PET/CT) in patients with diffuse large B-cell Lymphomas (DLBCL) presenting intermediate IPI score.

MATERIAL AND METHODS

Fifty-two patients (61 ± 13 yr) underwent PET/CT before the first-line chemotherapy. The mean SUVmax value, the summed MTV (cm(3) ; 42% threshold), and the cumulative TLG (g) were registered. The patients were followed up 18 months thereafter (range 3-41 months). The PET/CT results were compared to the event-free survival (EFS).

RESULTS

At univariate analysis, SUVmax and lactate dehydrogenase (LDH) levels were predictive, but discordantly. The Kaplan-Meier survival analysis for SUVmax showed a significant better EFS in patients presenting higher values as compared to those having lesser (P = 0.0002, HR 0.13). Summed MTV and cumulative TLG were not suitable for predicting EFS.

CONCLUSION

Despite the availability of new tools for the quantitative assessment of disease activity on PET/CT, the SUVmax rather than MTV and TLG remains the only predictor for EFS in DLBCL patients. The magnitude of glycolytic activity rather than the amount of metabolically active burden holds a predominant value for determining the response to chemotherapy in DLBCL.

When should FDG-PET be used in the modern management of lymphoma?

Positron Emission Tomography (PET) is a functional imaging technique that, combined with computerized tomography (PET-CT), is increasingly used in lymphoma. Most subtypes accumulate fluorodeoxyglucose (FDG) and the increased sensitivity of PET-CT, especially for extranodal disease, compared to CT, makes PET-CT an attractive staging tool. The availability of a staging PET-CT scan also improves the accuracy of subsequent response assessment. 'Interim' PET-CT can be used to assess early response and end-of-treatment PET-CT assesses remission. Clinical trials are currently seeking to establish whether the predictive value of PET-CT can be successfully used to guide individual treatment to reduce toxicity and/or to improve outcomes. Standardized methods for performing and reporting PET have been developed in the context of trials. The role of PET in transplantation selection is currently evolving, as it appears to be more accurate and prognostic than CT. The role of FDG PET-CT throughout the management course in patients with lymphoma is explored in this review, with areas discussed that may limit the use of PET-CT imaging which clinicians should be familiar with to inform practice.

Standardized uptake value for (18)F-fluorodeoxyglucose is correlated with a high International Prognostic Index and the presence of extranodal involvement in patients with diffuse large B-cell lymphoma

The aim of this study was to evaluate whether the maximum standardized uptake value (SUVmax) of (18)F-fluorodeoxyglucose (FDG) correlates with the International Prognostic Index (IPI) and the presence of extranodal involvement in patients with Diffuse Large B-Cell Lymphoma (DLBCL).

MATERIAL AND METHODS

77 patients (age: 57.2±18.5, 40F, 37M) with DLBCL who underwent FDG PET/CT for initial staging were included. SUVmax of the predominant lesions were compared to Ann Arbor stage, IPI scores, the presence of extranodal involvement and the number extranodal sites.

RESULTS

PET/CT detected nodal (n:25) and extranodal involvement (n:52) in all the patients. In 27 patients, extranodal disease could only be detected by PET. SUVmax of the predominant lesion in patients with extranodal disease was significantly higher than that of the patients who had only nodal disease (25±12 vs. 15.3±10 respectively, p=0.001). SUVmax significantly correlated with IPI scores; the average SUVmax was significantly correlated with the IPI: Mean SUVmax of the predominant lesion was 13.9±9.5 in patients with low risk (IPI=0-1), 14.2±8.8 in low-intermediate risk group (IPI=2) whereas 26.6±9.5 in high-intermediate risk group (IPI=3) and 25±13.6 in high risk group patients (IPI=4-5) (p=0.002). SUVmax was not correlated with clinical stage, the number of extranodal sites and serum LDH levels.

CONCLUSION

FDG uptake correlates with IPI and the presence of extranodal involvement in DLBCL. PET is a powerful method to detect extranodal disease in DLBCL. The correlation of SUVmax with these prognostic factors may highlight the importance of pretreatment FDG uptake as a metabolic marker of poor prognosis for patients with DLBCL.

Relationship between 2-deoxy-2-[(18)F]-fluoro-d-glucose uptake and clinicopathological factors in patients with diffuse large B-cell lymphoma

The aim of this study was to investigate correlations between the standardized uptake value of the biopsy site (BSUVmax) and levels of glucose transporter (GLUT)-1, GLUT-3 and hexokinase-II (HK-II), between BSUVmax and the Ki-67 proliferation index (MIB-1), and between BSUVmax and clinicopathological factors. Sixty-eight patients with diffuse large B-cell lymphoma (DLBCL) were included in this study. BSUVmax was significantly correlated with GLUT-1, GLUT-3 and the International Prognostic Index (IPI) (GLUT-1: r = 0.584, IPI: r = 0.363, p < 0.001; GLUT-3: r = 0.369, p = 0.009; IPI: r = 0.363, p = 0.004), but not with MIB-1 and HK-II. A statistically significant correlation was observed between GLUT-3 expression and each of IPI and gene expression profiling (GEP) (IPI: p = 0.0186; GEP: p = 0.0179). 2-Deoxy-2-[(18)F]-fluoro-d-glucose (FDG) uptake was significantly correlated with the levels of GLUT-1 and GLUT-3 and with IPI. The results indicated that GLUT-3 expression is related to GEP and IPI, and that BSUVmax and GLUT-3 may have a relationship with the prognosis of DLBCL.

18F-FDG PET is an independent outcome predictor in primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma is an aggressive non-Hodgkin lymphoma with poor prognosis. We evaluated pretreatment (18)F-FDG PET as a prognostic marker in primary CNS lymphoma.

METHODS

Forty-two immunocompetent patients with newly diagnosed primary CNS lymphoma who underwent pretreatment (18)F-FDG PET were retrospectively analyzed. Baseline status and response to treatment were evaluated by MR imaging. Tumor maximum standardized uptake values were assessed by volume-of-interest analyses using an automatic isocontour definition. A 10-step semiquantitative visual rating system (metabolic imaging lymphoma aggressiveness scale, or MILAS) was used to assess primary CNS lymphoma metabolism as a marker of clinical aggressiveness. Logistic regression, log-rank testing, and multivariable Cox regression were used to investigate the association between (18)F-FDG uptake and tumor response and survival.

RESULTS

Mean maximum standardized uptake value correlated linearly with MILAS. The distribution of patients according to MILAS (0-9) was 0%, 28.6%, 23.8%, 21.4%, 11.9%, 4.8%, 7.1%, 0%, 0%, and 2.4%. There was no correlation between MILAS and response to treatment. Respective 2- and 5-y survival rates were 52% and 32% for progression-free survival (PFS) and 64% and 50% for overall survival (OS). A cutoff at MILAS 3 was a good separator for PFS (median: 54.7 mo [≤3], 3.8 mo [>3], P = 0.0272) and OS (median: not reached [≤3], 13.8 mo [>3], P = 0.131). In multivariable analyses, increasing MILAS was significantly associated with shorter PFS (hazard ratio, 1.49, P = 0.006) and OS (hazard ratio, 1.43, P = 0.018).

CONCLUSION

Increased pretreatment (18)F-FDG uptake may offer new opportunities for baseline risk evaluation in untreated primary CNS lymphoma.

SUV on dual-phase FDG PET/CT correlates with the Ki-67 proliferation index in patients with newly diagnosed non-Hodgkin lymphoma

PURPOSE

PET using 18F-FDG integrated with CT is beneficial for staging patients with non-Hodgkin lymphoma (NHL). The Ki-67 index is used to assess the proliferation potential of tumor cells. The aim of this study was to evaluate the correlation of the Ki-67 index in tissue samples with the SUV at different sites on dual-phase FDG PET/CT of patients with newly diagnosed NHL.

MATERIALS AND METHODS

From September 2009 to March 2011, patients with newly diagnosed NHL who had received dual-phase FDG PET/CT for staging and biopsy samples that were evaluated for the Ki-67 expression were enrolled. The SUVmax of the biopsy site, the tumorous lesion sites, and 3 different bone marrow sites (right iliac crest, sternum, and L1) were measured. The SUVmean of the liver and spleen were also measured.

RESULTS

There were a total of 27 patients in this study. Significant correlations were observed between the Ki-67 index and the SUVmax of the right iliac crest in patients with early-stage disease (stage I and II) patients, the SUVmax of the biopsy and whole-body lesion sites in patients with late-stage disease (stage III and IV), and the retention index of SUVmax of the right iliac crest in patients whose bone marrow were involved by lymphoma cells.

CONCLUSIONS

For patients with newly diagnosed NHL, the significant correlation between the Ki-67 index and the SUV in this study suggests that dual-phase FDG PET/CT may be used as a noninvasive measurement of tumor proliferation.

Maximum standard uptake value of 18F-fluorodeoxyglucose positron emission tomography is a prognostic factor for progression-free survival of newly diagnosed patients with diffuse large B cell lymphoma

The treatment of patients with diffuse large B cell lymphoma (DLBCL) would be greatly facilitated with a rapid method for determining prognosis that can be performed more easily and earlier than cytological or specific pathological examinations. It has been suggested that newly diagnosed patients with DLBCL who have low maximum standard uptake value (SUV(max)) on (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) are more likely to be successfully treated and remain in remission compared with patients with high SUV(max), but this concept has been poorly studied. We retrospectively analyzed 50 patients with de novo DLBCL to evaluate the relationship between the SUV(max) and disease progression. For patients with low SUV(max) (n = 10) and high SUV(max) (n = 40) (P = 0.255), respectively, the 3-year overall survival rates were 90 and 72 %, and the progression-free survival (PFS) rates were 90 and 39 % (P = 0.012). By multivariate analysis, the revised International Prognostics Index (R-IPI) and SUV(max) at diagnosis were shown to predict longer PFS. The 3-year PFS for patients with low SUV(max) classified into the good prognosis group by R-IPI was 100 vs. 62 % for those with high SUV(max) (P = 0.161), and patients with low SUV(max) classified into the poor prognosis group by R-IPI was 80 vs. 18 % for those with high SUV(max) (P = 0.050). We conclude that the SUV(max) on FDG-PET for newly diagnosed patients with DLBCL is an important predictor of disease progression, especially for patients with poor prognosis by R-IPI.