18F-FDG PET/CT and extragastric MALT lymphoma: role of Ki-67 score and plasmacytic differentiation

Chemokine receptor-targeted PET/CT provides superior diagnostic performance in newly diagnosed marginal zone lymphoma patients: a head-to-head comparison with [18F]FDG

BACKGROUND

In patients with marginal zone lymphoma (MZL), [18F]FDG PET/CT provided inconsistent diagnostic accuracy. C-X-C motif chemokine receptor 4 (CXCR4) is overexpressed in MZL and thus, may emerge as novel theranostic target. We aimed to evaluate the diagnostic performance of CXCR4-targeting [68Ga]Ga-PentixaFor when compared to [18F]FDG PET/CT in MZL.

METHODS

Thirty-two untreated MZL patients (nodal, n = 17; extranodal, n = 13; splenic, n = 2) received [68Ga]Ga-PentixaFor and [18F]FDG PET/CT within median 2 days. We performed a visual and quantitative analysis of the total lymphoma volume by measuring maximum/peak standardized uptake values (SUVmax/peak), and calculating target-to-background ratios (TBR, defined as lesion-based SUVpeak divided by SUVmean from blood pool). Visual comparisons for both radiotracers were carried out for all target lesions (TL), and quantitative analysis of concordant TL evident on both scans. Last, MZL subtype analyses were also conducted.

RESULTS

On a patient-based level, [68Ga]Ga-PentixaFor identified MZL manifestations in 32 (100%) subjects (vs. [18F]FDG, 25/32 [78.1%]). Of the 256 identified TL, 127/256 (49.6%) manifestations were evident only on CXCR4-directed imaging, while only 7/256 (2.7%) were identified on [18F]FDG but missed by [68Ga]Ga-PentixaFor. In the remaining 122/256 (47.7%) concordant TL, [68Ga]Ga-PentixaFor consistently provided increased metrics when compared to [18F]FDG: SUVmax, 10.3 (range, 2.53-37.2) vs. 5.72 (2.32-37.0); SUVpeak, 6.23 (1.58-25.7) vs. 3.87 (1.54-27.7); P < 0.01, respectively. Concordant TL TBR on [68Ga]Ga-PentixaFor (median, 3.85; range, 1.05-16.0) was also approximately 1.8-fold higher relative to [18F]FDG (median, 2.08; range, 0.81-28.8; P < 0.01). Those findings on image contrast, however, were driven by nodal MZL (P < 0.01), and just missed significance for extranodal MZL (P = 0.06).

CONCLUSIONS

In newly diagnosed MZL patients, [68Ga]Ga-PentixaFor identified more sites of disease when compared to [18F]FDG, irrespective of MZL subtype. Quantitative PET parameters including TBR were also higher on [68Ga]Ga-PentixaFor PET/CT, suggesting improved diagnostic read-out using chemokine receptor-targeted imaging.

Exploring the efficacy of 18F-FDG PET/CT in hepatocellular carcinoma diagnosis: role of Ki-67 index and tumor differentiation

PURPOSE

The sensitivity of [18F] fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) for detecting hepatocellular carcinoma (HCC) has not been clarified thoroughly. Our study seeks to explore the association between the Ki-67 index and FDG-avidity in HCC tumors using 18F-FDG PET/CT.

METHODS

112 HCC lesions from 109 patients detected by 18F-FDG PET/CT were included retrospectively between August 2017 and May 2022, comprising 82 lesions in the training cohort and 30 in the validation cohort to simulate prospective studies. In the training cohort, lesions were stratified by a lesion-to-liver maximum standardized uptake value (SUVmax) ratio cut-off of 1.59. The relationships between lesion-to-liver SUVmax ratios and several clinical factors including tumor differentiation, alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), hepatitis B virus (HBV) infection, Ki-67 index et al. were assessed. These findings were subsequently validated in the independent validation cohort.

RESULTS

In the training cohort, group A1 lesions demonstrated a higher Ki-67 index (%, 40.00 [30.00, 57.50] vs. 10.00 [5.00, 28.75], p<0.001) than group A0, the positive correlation between FDG-avidity and Ki-67 index was revealed by multivariate analysis, OR=1.040, 95% CI of OR [1.004-1.077], p=0.030. The calculated cut-off value was 17.5% using the receiver operating characteristic (ROC) curve, with an area under curve (AUC) of 0.834 and 95% CI [0.742-0.926], p<0.001. These findings were further validated in the independent validation cohort, with similar results (AUC=0.875, 95% CI [0.750-1.000], p<0.001).

CONCLUSION

In comparison to tumor differentiation, Ki-67 index demonstrates a stronger association with FDG-avidity in HCC tumors, and when the Ki-67 index exceeds 17.5%, 18F-FDG PET/CT might serve as a useful indicator for HCC.

Thymic Extranodal Marginal-Zone Lymphoma of Mucosa-Associated Lymphoid Tissue: Pathological Features, 18F-FDG PET/CT Findings and Prognosis in 12 Cases

Purpose

Primary thymic extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a rare type of MALT lymphoma. We aim to investigate the clinicopathologic features, ¹⁸F-FDG PET/CT findings and outcomes for patients with primary thymic MALT lymphoma; to explore the correlation between metabolic parameters and immunohistochemical phenotypes.

Methods

A retrospective single-center study enrolled 12 patients with primary thymic MALT lymphoma between 2010 and 2021. Nineteen ¹⁸F-FDG PET/CT scans were performed, and clinicopathologic and immunohistochemical characteristics, PET/CT imaging features, and outcomes were analyzed.

Results

The male-to-female ratio was 1. The median age at diagnosis was 40 (range 31–68). The long diameter of the lesions ranged from 3.5 to 15.7. Histopathological examinations revealed that the normal thymic lobular architecture was effaced by a diffuse lymphoid infiltrate, but residual Hassall corpuscles could still be identified, mostly with CD20+, PAX5+, CD3-, CD23-, CD10-, BCL-6-, cyclin D1-, EBER- and low Ki-67. The gene rearrangement indicated that the IGH gene but not TCR gene was found in 7 patients. Six initial PET/CT scans showed a mean SUVmax of 6.8 (range, 3.1–12.4), a mean MTV = 40.0 (range, 6.7–81.4), and a mean TLG = 144.3 (range, 19.7–286.4). During the follow-up period, there was no death except for the patient with DLBCL who died 59 months after diagnosis of primary thymic MALT. No significant correlation between SUVmax and Ki-67 index was observed (r = 0.355, P > 0.05).

Conclusion

Primary thymic MALT lymphoma should be considered in patients with multilocular cystic lesions with different degrees of ¹⁸F-FDG uptake in the anterior mediastinum. The results of this study showed no correlation between SUVmax and Ki-67 index.

Clinicopathologic Characteristics Associated with Prognosis in Ocular Extranodal Marginal Zone B Cell Lymphoma

Background and Objectives: Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT) type is the most common subtype of the ocular adnexal lymphoma. Despite its excellent prognosis, some patients experience partial remission or progressive disease. We aimed to evaluate clinicopathologic differences in the treatment responder group by comparing complete remission (CR) and non-complete remission (non-CR). Materials and Methods: This study retrospectively reviewed 48 patients who were diagnosed with ocular adnexal MALT lymphoma at Ulsan University Hospital between March 2002 and August 2018. Patients who were followed up for less than 6 months were excluded. Histologic and clinical features were analyzed. The patients were divided into two groups: CR and non-CR. Results: Among the 48 patients, 33 achieved CR and 15 achieved non-CR during the median follow-up period of 40.00 months (range, 7-109 months). In univariable analysis, more patients tend to undergo treatment in the CR group, and post-radiotherapy (post-RT) SUVmax, PET and serum lactate dehydrogenase (LDH) levels were higher in the non-CR group (p = 0.043, p = 0.016, and p = 0.042, respectively). In a multivariable analysis, only application of treatment, including radiotherapy or chemotherapy with immunotherapy, was related to CR (odd ratio 7.301, 95% confidence interval 1.273-41.862, p = 0.026). In subgroup analysis according to the site of involvement, none of the variables were significant except for the post-RT SUVmax of PET and level of serum LDH in the non-conjunctiva group (p = 0.026, and p = 0.037, respectively). Seven (14.6%) patients had a recurrence, and those with a recurring site other than the primary site had a higher Ki-67 labeling index, although it was not statistically significant (9.56% vs. 18.00%, p = 0.095). Conclusions: Although belonging to the early stages, the non-CR rate was high in patients with high serum LDH levels, and recurred patients had higher Ki-67. Thus, considering active treatment is recommended in this group of patients.

Clinical and pathological predictors for FDG-PET/CT avidity in patients with marginal zone lymphoma-a retrospective cohort study

BACKGROUND

The clinical value of FDG-PET/CT for staging and monitoring treatment response in patients with aggressive lymphoma is well established. Conversely, its role in the assessment and management of marginal zone lymphoma (MZL) is less conclusive. We aimed to assess clinical, laboratory, and pathological predictors for FDG uptake in these patients, in an attempt to identify MZL patients whose management will benefit from this imaging modality.

METHODS

In this single-center, retrospective cohort study, we included all adult patients diagnosed with MZL at the Rabin Medical Center between January 2006 and December 2020 who underwent FDG-PET/CT at the time of diagnosis. Primary outcomes were FDG avidity (defined as a visual assessment of at least moderate intensity), SUVmax, and SUVliver. Variables such as advanced clinical stage, primary disease site, hemoglobin level (Hb), platelet count (Plt), serum albumin, LDH level, β-2 microglobulin, and Ki 67 index were evaluated univariate and multivariate analysis using logistic and linear regression models. Association between FDG avidity and progression-free and overall survival was evaluated using Kaplan-Meier curves and Cox regression analysis.

RESULTS

A total of 207 MZL patients were included in this study, 76 of whom (36.7%) had FDG-avid disease. Baseline patients' characteristics such as age, gender, and comorbid conditions were similar between patients with and without significant FDG uptake. In a multivariate logistic regression model, non-gastric MALT (OR 4.2, 95% CI 1.78-10), Ki 67 index ≥ 15% (OR 3.64, 95% CI 1.36-9.76), and elevated LDH level (OR 8.6, 95% CI 3.2-22.8) were all associated with positive FDG avidity. In a multivariate linear regression model, a combination of advanced clinical stage, specific disease subtypes, LDH level, and Ki 67 index predicted the value of SUVmax (P value < 0.001; adjusted R2 = 33.8%) and SUVmax/SUVliver (P value < 0.001; adjusted R2 = 27%). Baseline FDG avidity was associated to PFS and OS only in univariate analyses.

CONCLUSIONS

In this retrospective cohort study, we present prediction models for positive FDG uptake and SUVmax in MZL patients. These models aim to help clinicians choose patients suitable for incorporation of FDG-PET/CT for staging and monitoring disease and reduce the costs of redundant tests.

The role of 18F-FDG PET/CT in diagnosis and treatment evaluation for ocular adnexal mucosa-associated lymphoid tissue lymphoma

OBJECTIVE

The purpose of this study is to evaluate the value of fluorine-18-fludeoxyglucose positron emission tomography (¹⁸F-FDG PET)/CT in the diagnosis and treatment evaluation of ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma.

METHODS

70 patients with OAML who received radiotherapy were recruited in our study. All the patients had the ¹⁸F-FDG PET/CT examination before the treatment. We retrospectively reviewed the medical records, pathological reports, laboratory results, and imaging features of all patients. The associations between ¹⁸F-FDG PET/CT parameters and Epstein-Barr virus antibodies, treatment response, MRI data, and Ki-67 expression were investigated.

RESULTS

The PET/CT scan indicated that 80% (56/70) of the patients showed orbital FDG avidity. The median level of maximum standardized uptake value (SUVmax) of the lesions was 4.65 ± 3.00 (range:1.2-13.5). 92.0% (46/50) of the mass-forming lesions showed ¹⁸F-FDG avidity, while only 50.0% (10/20) of the non-massive lesions had ¹⁸F-FDG avidity (χ² = 13.23, p=0.01). The SUVmax in orbit, conjunctiva, and lacrimal gland lymphoma were 5.6, 2.9, and 3.7, respectively. A significant difference was identified of SUVmax among the three locations' lymphoma using one-way ANOVA analysis (F = 5.039, p = 0.01). After completion of radiotherapy, the complete remission rate was achieved in 30.8% (4/13) of the patients without ¹⁸F-FDG avidity, and 70.4% (38/54) in cases with ¹⁸F-FDG avidity (χ² = 5.43, p = 0.02). The correlation between high Ki-67 score and ¹⁸F-FDG avidity was confirmed (χ² = 3.916, p = 0.048); however, no significant correlation was found between the SUVmax and Ki-67 score of the lesions (p = 0.971). Three patients (3/70, 4.3%) were upregulated the stage via PET/CT.

CONCLUSION

¹⁸F-FDG PET/CT had some potential values in the diagnosis and assessment of treatment response in patients with OAML.

ADVANCES IN KNOWLEDGE

The value of ¹⁸F-FDG PET/CT for patients with OAML.

Is There a Role for [18F]FDG PET-CT in Staging MALT Lymphoma?

Simple Summary

MALT lymphoma represents a relatively rare lymphoma subtype that arises in different extranodal anatomic locations. In the current paper we summarize our experience in assessing disease extent and metabolic characteristics of MALT lymphomas with [¹⁸F]FDG PET-CT at staging, and aim to highlight the strengths and challenges this imaging modality poses. In our data, all extranodal lesions located in subcutaneous-tissue, lung and liver were detected on PET, while some of those located in other tissues (such as along the digestive tract) were not detected on PET. We also evaluated the predictive role of PET in these patients, and found that increased [¹⁸F]FDG-uptake in extranodal lesions was associated with worse disease progression.

Abstract

The role of ¹⁸F-fluorodeoxyglucose ([¹⁸F]FDG) positron emission tomography—computed tomography (PET-CT) in assessing mucosa-associated lymphoid tissue (MALT) lymphoma is debatable. We retrospectively explored the role of [¹⁸F]FDG PET-CT in staging and predicting progression-free-survival (PFS) of patients with newly-diagnosed MALT lymphoma. Sixty-six studies were included. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were documented in the “hottest” extranodal and nodal lesions. Extranodal lesions and accompanying nodal disease were detected on PET in 38/66 (57.6%) and 13/66 (19.7%) studies, respectively. Detection rate of extranodal lesions differed significantly between those located in tissues with high/heterogeneous (e.g., stomach) vs low/homogenous (e.g., subcutaneous-tissue, lung) physiologic [¹⁸F]FDG-uptake (40.4% vs. 100%, p < 0.01). Nodal lesions had significantly lower SUVmax, MTV and TLG compared with extrandodal lesions in the same patients. Detection and [¹⁸F]FDG-avidity of extranodal lesions were higher in patients with advanced, bulky disease and concomitant marrow/nodal involvement. Increased SUVmax of extranodal lesions predicted shorter PFS (HR 1.10, 95% CI 1.01–1.19, p = 0.02). Higher SUVmax and TLG showed trends towards shorter PFS in patients with localized disease. In conclusion, detection rate of extranodal MALT lymphoma lesions located in tissues with low/homogeneous physiologic [¹⁸F]FDG-uptake is excellent on [¹⁸F]FDG PET-CT. When detected, SUVmax of extranodal lesions may predict PFS.

Hepatic Lesion of Mucosa-Associated Lymphoid Tissue Lymphoma Revealed by Al18F-NOTA-FAPI-04 PET/CT

ABSTRACT

A middle-aged man was newly diagnosed with mucosa-associated lymphoid tissue lymphoma with secondary liver involvement. The hepatic lesion was not shown on FDG PET/CT but FAPI (fibroblast-activated protein inhibitor) PET/CT, which revealed abnormal FAPI accumulation. This case demonstrated that FAPI PET/CT might provide value in hepatic mucosa-associated lymphoid tissue lymphoma.

Correlation of 18F-FDG PET/CT SUVmax with clinical features, D-dimer and LDH in patients with primary intestinal lymphoma

Objective

To investigate the characteristics of fluorine-18-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) maximum standardized uptake value (SUVmax) in primary intestinal lymphoma (PIL) and its correlation with D-dimer and lactate dehydrogenase (LDH).

Methods

Fifty-two patients diagnosed with PIL from June 2016 to December 2019 were analyzed. All patients underwent 18F-FDG PET/CT. The relationships between SUVmax and different pathological subtypes, clinical stages and risk grades were analyzed. The correlations between SUVmax and Ki-67, LDH and D-dimer were determined. Additionally, PET/CT imaging results were collected from 35 patients with primary intestinal cancer (PIC) and compared with the imaging features of PIL.

Results

SUVmax was significantly different between PIL and PIC groups and various PIL pathological subgroups. Patients in the high-risk PIL group had markedly higher SUVmax values than the intermediate-risk and low-risk groups. A significant positive correlation was observed between SUVmax and Ki-67 in patients with PIL. SUVmax was significantly different between the elevated and normal D-dimer groups. D-dimer showed a positive correlation with SUVmax.

Conclusion

18F-FDG PET/CT SUVmax reflects the aggressiveness of lymphoma to a certain degree, is correlated with Ki-67 and determines the risk grades of PIL. Moreover, it facilitates differential diagnosis, clinical staging and treatment based on D-dimer levels.

Correlation between semiquantitative and volumetric 18F-FDG PET/computed tomography parameters and Ki-67 expression in breast cancer

OBJECTIVES

To evaluate the relationship between semiquantitative and volumetric parameters on 18F-FDG PET/computed tomography (CT), including maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), tumor to liver ratio (TLR) and tumor to mediastinum ratio (TMR) with the level of Ki-67 expression in breast cancer.

PATIENT AND METHODS

We retrospectively reviewed 105 female patients with newly diagnosed breast cancer who underwent baseline 18F-FDG PET/CT and had immunohistochemical staining to determine the level of Ki-67 expression. The following PET parameters were measured (SUVmax, SUVmean, MTV, TLG, TLR and TMR) and correlated with level of Ki-67 expression.

RESULTS

Significant moderate positive correlations were found between the PET parameters (primary SUVmax, SUVmean, TLG, TLR and TMR) and level of Ki-67 expression. The primary SUVmax had the highest correlation coefficient (r = 0.461) followed by TMR (r = 0.455) and P value of <0.001 for both. In ROC analysis, primary SUVmax had the largest area under the curve (0.806, P = 0.0001), with sensitivity of 76.5 % and specificity of 75% for prediction of high Ki-67 level. In univariate analysis, all PET parameters, patient age, tumor grade, molecular subtype, estrogen receptor and progesterone receptor status were significantly associated with Ki-67 level. In multivariate regression analysis, only tumor grade [odds ratio (OR) = 20.460, 95% confidence interval (CI): 11.360-29.559, P = <0.0001], molecular subtype (OR = -21.894, 95% CI: -37.921 to -5.866, P = 0.008), SUVmax (OR = 2.299, 95% CI: 0.703-3.895, P = 0.005) and TLR (OR = -4.908, 95% CI: -9.476 to -0.340, P = 0.035) were found to be the strongest independent predictor factors for the level of Ki-67 expression and hence proliferative activity of malignant cells in breast cancer.

CONCLUSION

The semiquantitative parameters and volumetric 18F-FDG PET/CT parameter, that is, TLG correlated well with proliferation marker Ki-67 in breast cancer. 18F-FDG PET/CT imaging can be used as a useful noninvasive diagnostic tool in imaging cellular proliferation and hence may substitute for in vitro testing of molecular markers in the diagnoses and staging of breast cancer.

A case of primary hepatic extranodal marginal zone B-cell mucosa-associated lymphoid tissue (MALT) lymphoma treated by radiofrequency ablation (RFA), and a literature review

Primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma is an extremely rare liver malignancy that usually lacks characteristic imaging findings and which is often misdiagnosed. We report a 63-year-old woman diagnosed with primary hepatic extranodal marginal zone B-cell lymphoma, MALT type. The patient underwent needle biopsy and radiofrequency ablation (RFA), and showed no signs of relapse during the 12-month postoperative follow-up. This case stresses the rarity of primary hepatic MALT-type lymphoma and the unique and effective treatment for this patient. Our patient received RFA, which showed good efficacy and which provides a new option for the treatment of hepatic MALT lymphoma. We also present our findings from a systematic review to improve the current understanding of this disease.

How can we assess and measure prognosis for MALT lymphoma? A review of current findings and strategies

INTRODUCTION

: MALT (mucosa associated lymphoid tissue) lymphoma is a distinct type of B-cell lymphoma characterized by extranodal manifestation and an indolent clinical course with 10-year survival rates up to 90%. However, transformation to aggressive lymphoma may occur and treatment is indicated in case of symptomatic or progressive disease.

AREAS COVERED

: This review covers clinical and biological features potentially related to prognosis and outcome of MALT lymphoma patients, as well as available prognostic tools and risk stratification systems with a focus on the MALT-IPI (international prognostic index) and the POD24 (progression of disease at 24 months) cohort. In addition, we address the role of watch-and-wait, the importance of defining the optimal time point for treatment initiation and the relevance of depth of remission, which appear to be some of the central questions for physicians involved in the care of MALT lymphoma patients. A computerized database search using PubMed® was performed to identify available publications on prognostic factors and risk stratification tools in MALT lymphoma.

EXPERT OPINION

: Despite the development of disease-specific risk stratification systems, there is no clear concept how to measure prognosis and tailor treatment. Careful observation of the individual clinical course is essential to assess the optimal time point of treatment initiation and avoid overtreatment, particularly in patients with disseminated disease. In addition, early detection of patients with histological transformation is necessary, as these patients face a poor prognosis.

Correlation between 18 F-FDG PET/CT semiquantitative parameters and Ki-67 expression in pulmonary mucosa-associated lymphoid tissue lymphoma

INTRODUCTION

This study aims to investigate the correlation between ¹⁸ F-Fluoro-d-glucose positron emission tomography/computed tomography (¹⁸ F-FDG PET/CT) semiquantitative parameters and Ki-67 expression in pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma.

METHODS

Twenty-eight patients with histologically confirmed pulmonary MALT lymphoma in 29 lesions who underwent ¹⁸ F-FDG PET/CT were retrospectively analysed. PET/CT images were analysed visually and semiquantitatively by measuring maximum standardized uptake value (SUV_max ), mean standardized uptake value (SUV_mean ), metabolic tumour volume (MTV) and total lesion glycolysis (TLG). The correlation between morphological pattern, tumour size, Ki-67 expression and PET/CT semiquantitative parameters were also analysed.

RESULTS

There were 16 male patients (57.1%) and 12 female patients (42.9%), and the mean age was 57.6 ± 9.7 years (range 43-73 years). Twenty-nine pulmonary lesions were identified in 28 patients: 12 (41.4%) presenting as consolidation, 9 (31.0%) as nodules, 5 (17.2%) as masses and 3 (10.3%) as ground glass opacities (GGOs). All of the 29 lesions were ¹⁸ F-FDG avid. SUV_max of the lesions was 4.4 ± 3.0 (range 1.1-15.3), SUV_mean was 2.8 ± 1.9 (range 0.8-10.3), MTV was 15.9 ± 17.6 (range 0.9-82.1) and TLG was 48.7 ± 56.6 (range 0.9-205.6). The PET/CT semiquantitative parameters were not correlated with morphological pattern of pulmonary MALT lymphoma, which were correlated significantly with tumour size and Ki-67 expression.

CONCLUSION

Pulmonary MALT lymphomas are ¹⁸ F-FDG avid, and ¹⁸ F-FDG PET/CT semiquantitative parameters (SUV_max , SUV_mean , MTV and TLG) are significantly correlated with tumour size and Ki-67 expression. ¹⁸ F-FDG PET/CT plays a potential role in identifying lung MALT lymphomas with higher proliferation and more aggressive behaviour in clinical practice.

Preliminary evidence of imaging of chemokine receptor-4-targeted PET/CT with [68Ga]pentixafor in non-Hodgkin lymphoma: comparison to [18F]FDG

BACKGROUND

In order to study the CXCR4 expression with [⁶⁸Ga]pentixafor PET in different types of non-Hodgkin lymphoma, we performed a retrospective study to describe the [⁶⁸Ga]pentixafor PET/CT imaging in a spectrum of lymphomas and to compare it with [¹⁸F]FDG PET/CT.

RESULTS

Twenty-seven patients with newly diagnosed non-Hodgkin lymphoma were recruited retrospectively. [⁶⁸Ga]pentixafor PET showed increased radioactivity in lymphoplasmacytic lymphoma (n = 8), marginal zone lymphoma (n = 4), diffuse large B cell lymphoma (n = 3), follicular lymphoma (n = 2), mantle cell lymphoma (n = 1), unclassified indolent B cell lymphoma (n = 3), and enteropathy associated T cell lymphoma (n = 3). However, peripheral T cell lymphoma, not otherwise specified (n = 1), and NK/T cell lymphoma (n = 2) were not avid for [⁶⁸Ga]pentixafor. In comparison to [¹⁸F]FDG PET, [⁶⁸Ga]pentixafor PET demonstrated more extensive disease and higher radioactivity in lymphoplasmacytic lymphoma and marginal zone lymphoma.

CONCLUSION

CXCR4 expression varies in different types of non-Hodgkin lymphoma. Overexpression of CXCR4 was detected with [⁶⁸Ga]pentixafor PET/CT in lymphoplasmacytic lymphoma, marginal zone lymphoma, diffuse large B cell lymphoma, follicular lymphoma, mantle cell lymphoma, unclassified indolent B cell lymphoma, and enteropathy associated T cell lymphoma. The uptake of [⁶⁸Ga]pentixafor was higher than [¹⁸F]FDG in lymphoplasmacytic lymphoma and marginal zone lymphoma.

The value of multiparameter 18F-FDG PET/CT imaging in differentiating retroperitoneal paragangliomas from unicentric Castleman disease

The aim of this study was to investigate the value of multiple parameters retrieved from the FDG PET/CT studies, including SUVmax, SUVmean, SUVpeak, MTV, TLG, tumour size in differentiating retroperitoneal paragangliomas from UCD. 28 patients with solitary retroperitoneal masses who had undergone preoperative 18F-FDG PET/CT were retrospectively evaluated. Histopathology by surgical resection confirmed 17 paragangliomas and 11 UCDs. SUVmax, SUVmean, SUVpeak, MTV, TLG, and tumour size of 18F-FDG PET/CT were measured for each patient. Mann-Whitney U-test was used to assess differences in multiple parameters between paragangliomas and UCDs. The ROC curve analysis was performed to determine the differential diagnostic value of these parameters. Paragangliomas presented significantly higher SUVmax (P < 0.001), SUVmean (P = 0.001), SUVpeak (P < 0.001), and TLG (P = 0.024) than UCDs, whereas no significant difference was observed in MTV. The AUCs for differentiating paragangliomas and UCDs were 0.920, 0.888, 0.909, and 0.765 for SUVmax, SUVmean, SUVpeak, and TLG, respectively. The SUVmax cut-off of 7.75 yielded 82.4% sensitivity and 100% specificity for predicting paragangliomas. This study indicated that 18F FDG PET/CT-derived multiple metabolic parameters are useful in distinguishing between paragangliomas and UCDs. SUVmax showed the best result for the differential diagnosis of these two diseases among multiple metabolic parameters.

Prognostic Value of 18F-FDG PET/CT Metabolic Parameters in Splenic Marginal Zone Lymphoma

INTRODUCTION

Splenic marginal zone lymphoma (SMZL) is an indolent non-Hodgkin lymphoma usually with a good prognosis, but no clear metabolic behavior at fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). The aim of our analysis was to investigate the prognostic role of baseline 18F-FDG PET/CT parameters in SMZL.

MATERIALS AND METHODS

We retrospectively included 42 patients who received 18F-FDG-PET/CT before any treatments, and PET images were evaluated visually and semi-quantitatively by measuring lesion to liver (L-L) maximum standardized uptake volume (SUVmax) ratio (L-L SUV R), lesion to blood-pool SUVmax ratio (L-BP SUV R), metabolic tumor volume, and total lesion glycolysis. Progression-free (PFS) and overall survival (OS) curves were plotted according to the Kaplan-Meier method.

RESULTS

In all patients, an increased splenic FDG uptake (higher than the background) was identified, showing the presence of diffuse spleen uptake in 35 patients and focal uptake in the remaining 7 patients. At a median follow-up of 51 months, relapse or progression of disease occurred in 23 patients with an average time of 38.1 months from the baseline 18F-FDG PET/CT, and death occurred in 4 patients with an average time of 26.8 months. The estimated 2-year PFS and OS rates were 78% and 90%, respectively, whereas 5-year PFS and OS rates were 63% and 82%, respectively. At multivariate analysis, only L-L SUV R and L-BP SUV R were independent prognostic factors for PFS. In addition, no significant association was discovered for OS, considering all features.

CONCLUSIONS

L-L SUV R and L-BP SUV R were independently correlated with PFS.

PET/CT in Disease Detection and Follow-up of Subcutaneous Involvement in Marginal Zone Lymphoma

BACKGROUND

The value of positron emission tomography/computed tomography (PET/CT) in the staging and assessment of treatment response in marginal zone lymphoma (MZL) lymphomas remains controversial. We investigated radiologic characteristics of subcutaneous MZL as imaged on PET/CT scans.

PATIENTS AND METHODS

From the records of a single medical center, for the years 2008 and 2017, we identified subcutaneous lesions in PET/CT scans of patients with histopathologically confirmed MZL in sites other than subcutaneous tissue.

RESULTS

Of 571 scans of 178 patients, subcutaneous lesions were found in 20 (11%). Lesions were located in soft tissue structures, mainly along the lateral aspects of the buttocks, thighs and lower and upper back areas, the flank, and the shoulders. Median lengths of the long and short axes of the lesions were 2.0 (range, 1.1-6.0) cm and 0.8 (range, 0.3-2.0) cm, respectively. Median standardized maximum uptake value was 2.3 (range, 0.9-7.6). In 12 patients (60%), MZL was diagnosed at an early stage; 15 (75%) had lymph node involvement and 10 (50%) extranodal involvement. One had spleen and 2 had cutaneous involvement; none had gastric findings.

CONCLUSION

The findings of this study support the usefulness of PET/CT in the detection of subcutaneous MZL as well as in staging and treatment decisions.

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.

Role of F-18 FDG PET/CT in non-conjunctival origin ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphomas

Background

Despite the widespread use of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in the diagnosis and response assessment of patients with lymphoma, few studies have assessed its value in ocular adnexal lymphomas. The purpose of this study was to evaluate the role of FDG PET/CT in staging of non-conjunctival origin ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphomas (OAML). In addition, the diagnostic sensitivity of FDG PET/CT was compared with magnetic resonance imaging (MRI). FDG PET/CT of 123 consecutive patients with pathologically proven OAML between January 2009 and February 2016 were retrospectively reviewed. The patients with MALT lymphoma originating from conjunctiva were excluded. A total 50 patients with non-conjunctival origin OAML were assessed. Maximum standardized uptake value (SUVmax) and additional PET parameters were measured for all lesions. Sensitivity for primary tumor detection was compared with MRI.

Results

Ten patients had bilateral OAML and total 60 OAML lesions were analyzed. MRI was missing in one patient. The tumor locations were as follows: eyelid, 9; lacrimal gland, 18; orbit, 33. Fifty lesions (83.3%) were FDG-avid tumors with mean ± SD SUVmax 4.8 ± 2.4 (range 2.0~11.1). The mean SUVmax according to tumor location were as follows: eyelid, 3.7 ± 1.1 (2.8~5.3); lacrimal gland, 3.6 ± 1.4 (2.1~6.4); orbit, 5.7 ± 2.6 (2.0~11.1). Mean SUVmax among the 3 locations were statistically different (P = 0.010). The sensitivity was calculated as 83.1% (49/59) for FDG PET/CT and 89.8% (53/59) for MRI, which were statistically comparable (P = 0.219 by McNemar’s test). Seven of 50 patients (14%) were upstaged by detection of extraocular lesions by FDG PET/CT (1 kidney and lung, 1 tonsil, 4 cervical LNs, 1 sacral foramen).

Conclusion

83.3% of the non-conjunctival origin OAML were FDG-avid tumors, with FDG PET/CT showing comparable sensitivity to that of MRI. FDG PET/CT detected unsuspected extraocular lymphoma involvement in 14% of the patients. FDG PET/CT performed for staging of non-conjunctival origin OAML may thus guide therapeutic management.

18F-FDG PET/CT or PET Role in MALT Lymphoma: An Open Issue not Yet Solved-A Critical Review

Mucosa-associated lymphoid tissue (MALT) lymphoma involves the mucosa-associated lymphoid tissue potentially arising from any mucosal site, with the stomach as the most common site of involvement. MALT lymphoma is not usually an aggressive disease with a good prognosis except for selected cases. Fluorine-18 (¹⁸F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is a noninvasive imaging tool used for staging, restaging, and evaluation of the treatment response in non-Hodgkin and Hodgkin lymphoma. However, its effective role in MALT lymphoma is not yet clear. The open question is whether these lymphomas are ¹⁸F-FDG avid or not, with conflicting results reported in the literature. Consequently, the possible clinical role of ¹⁸F-FDG PET/CT for staging and restaging purposes is under debate. The aim of the present review was to analyze the reported data about the role of ¹⁸F-FDG PET or PET/CT in patients with MALT lymphoma. We performed a comprehensive computer literature search of the Scopus, Cochrane, PubMed/MEDLINE, and Embase databases, including articles reported up to August 2019. We included 32 studies that had analyzed ¹⁸F-FDG PET or PET/CT for patients with MALT lymphoma. We analyzed the metabolic behavior of MALT lymphoma using ¹⁸F-FDG PET and the effect of the PET findings in the staging, treatment response evaluation, and prognosis.

13N-NH3 PET/CT in oncological disease

¹³N-Ammonia (¹³N-NH₃) is widely used positron emission tomography/computed tomography (PET/CT) radiotracer for the measurement of myocardial blood perfusion; the possible role of ¹³N-NH₃ PET or PET/CT in oncological disease is not yet clear. Aim of this review is to evaluate the diagnostic performances of ¹³N-NH₃ PET in this field. A comprehensive computer literature search of the PubMed/MEDLINE, Scopus, and Embase databases was conducted including articles up to June 2019. Eighteen articles were finally included in the review. From the analyses of the selected studies, the following main findings could be drawn: (1) ¹³N-NH₃ PET is useful in discriminating between gliomas and non-neoplastic brain lesions, and among gliomas between high-grade and low-grade gliomas; (2) ¹³N-NH₃ PET have better diagnostic performance than ¹⁸F-FDG in studying gliomas; (3) a combination of ¹³N-NH₃ PET and ¹⁸F-FDG PET may be useful to differentiate between several cerebral lesions (gliomas, cerebral lymphoma, meningioma); (4) only preliminary results about the positive impact in liver and prostate cancer.

Uptake of [18F]fluorodeoxyglucose in initial positron-emission tomography predicts survival in MALT lymphoma

The role of [¹⁸F]fluorodeoxyglucose (FDG) positron-emission tomography (PET) in mucosa-associated lymphoid tissue (MALT) of marginal zone lymphoma remains poorly defined. We correlated initial PET with pathology, clinical factors, and outcome. From January 2001 to July 2012, 173 MALT lymphoma patients with a biopsied lesion identified on PET within 90 days of tissue biopsy were analyzed. PET positivity and intensity of FDG uptake were correlated with clinical factors and patient outcome. Among 173 accrued cases, biopsied site was PET avid in 123 patients (71%); median standardized uptake value (SUV) was 6.0 (range: 0.7-28.0), and SUV >10.0 in 20 patients (16%). PET avidity varied by organ sites. PET positivity correlated with higher International Prognostic Index, but not with 5-year overall survival (OS; 96% vs 88%, PET negative vs positive, P = .229) or 5-year progression-free survival (67% vs 56%, P = .493). SUV was an independent prognostic factor of OS, and an increased SUV was associated with a decreasing 5-year OS. Patients who presented with SUV ≥10 had a higher rate of subsequent large cell transformation (20% vs 5%, P = .035) and inferior OS (78% vs 92%, P = .008). The exact role of FDG PET in the management of MALT lymphoma, beyond initial staging, remains to be defined.

Prognostic role of baseline 18 F-FDG PET/CT parameters in MALT lymphoma

Mucosa-associated lymphoid tissue (MALT) lymphoma is an indolent lymphoma with good prognosis and variable fluorine-18 fluorodeoxyglucose (¹⁸ F-FDG) avidity. Many possible prognostic factors have been investigated with controversial results, but the possible prognostic role of ¹⁸ F-FDG positron emission tomography/computed tomography (PET/CT) remains unclear. Our aim was to evaluate the prognostic impact of qualitative and semiquantitative baseline PET/CT parameters on outcome of MALT lymphoma. We retrospectively enrolled 161 patients with histologically confirmed MALT lymphoma who underwent ¹⁸ F-FDG PET/CT before any treatment. PET images were qualitatively and semiquantitatively analyzed by measuring the maximum standardized uptake value body weight (SUVbw), lean body mass (SUVlbm), body surface area (SUVbsa), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). The Kaplan-Meier method was used to estimate the progression-free survival (PFS) and overall survival (OS) times. Cox regression models were performed to determine the relation between PET/CT features and OS and PFS. Ninety-eight patients had positive ¹⁸ F-FDG PET/CT showing ¹⁸ F-FDG uptake (mean SUVbw, 10.1; SUVlbm, 7.2; SUVbsa, 2.7; MTV, 88.8; and TLG, 526); the remaining 63 were not ¹⁸ F-FDG avid. ¹⁸ F-FDG avidity was significantly correlated with tumor size and Ki-67 score. Relapse/progression of disease occurred in 47 patients with an average time of 40.2 months; death occurred in 12 patients with an average of 59 months. At a median follow-up of 62 months, median PFS and OS were 52 and 62 months, respectively. Advanced tumor stage and extragastric site were demonstrated to be independent prognostic factors for PFS, while only tumor stage for OS. Instead, PET/CT parameters were not related to survival, despite positive correlation at univariate analysis between MTV and TLG with PFS and positive PET/CT with PFS and OS. In conclusion, a 61% rate of PET avidity in biopsy-confirmed MALT lymphoma was found, and it was correlated with tumor size and Ki-67 score. Only tumor stage and localization were independently correlated with PFS and OS.

18F-FDG PET/CT in splenic marginal zone lymphoma

PURPOSE

The detection rate and the metabolic behavior of 18F-FDG-PET/CT in splenic marginal zone lymphoma (SMZL) are not yet clear. Our aim was to investigate the metabolic behavior of SMZL and whether the tumor stage (acc. Ann Arbor) epidemiological (age, gender), histological (Ki-67 index, plasmacytic differentiation), and morphological (splenic diameter maximum) features might be related to 18F-FDG PET/CT results.

METHODS

Fifty-one patients (34 male, 17 female; average age 70 years) with histologically confirmed SMZL who underwent a 18F-FDG PET/CT for initial staging were included: PET/CT images were analyzed visually and semi-quantitatively (SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio). Splenic uptake was divided as diffuse or focal.

RESULTS

Thirty-nine patients (76%) had FDG-avid SMZL (7 with focal splenic lesions and 32 with diffuse splenic uptake), while the remaining 12 had no increased splenic uptake. Among patients with FDG-avid lesions, average SUVmax was 4.3, lesion-to-liver SUVmax ratio 2.3, and lesion-to-blood pool SUVmax ratio 3. 18F-FDG avidity was significantly associated with Ki-67 index and not correlated with other features. Semiquantitative PET/CT parameters (SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio) did not correlate significantly with any variable. Progression-free survival time was not influenced by FDG avidity of SMZL.

CONCLUSIONS

18F-FDG avidity was noted in 76% of SMZL with diffuse splenic uptake as main pattern of presentation and is correlated with Ki-67 score only.

Metabolic behavior and prognostic value of early and end of treatment 18F-FDG PET/CT in adult Burkitt's lymphoma: the role of Deauville and IHP criteria

Burkitt's lymphoma is a lymphoma with unclear metabolic behavior at 18F-FDG-PET/CT and no validated criteria in treatment evaluation and prediction of outcome exist. Sixty-five patients were retrospectively included: all underwent baseline 18F-FDG-PET/CT, 56 interim PET/CT (iPET/CT) and 54 end of treatment PET/CT (eotPET/CT) after chemotherapy. Interim and eotPET/CT results were visually interpreted according to the criteria of the IHP and Deauville-five-point-scale. Results were correlated with PFS and OS to assess and to compare the predictive value of iPET and eotPET according to each criterion. All baseline PET/CT showed increased 18F-FDG uptake in nodal and extranodal lesions. The median PFS and OS were 44.6 and 48.2 months with 3-year and 5-year PFS of 76% and 62% and 3-year and 5-year OS of 71% and 57%, respectively. EotPET/CT results using DC and IHP significantly correlate with OS and PFS; while iPET/CT did not correlated with OS and PFS.

18F-FDG PET/CT in primary brain lymphoma

The actual role of 18F-FDG PET/CT in evaluating primary brain lymphoma is still an open issue. Brain lymphoma usually show elevated 18F-FDG uptake, often higher than other brain tumors or inflammatory processes, but the metabolic behavior of this lymphoma is not still understood. Our aim was to investigate the particular metabolic behavior of this lymphoma. Forty six patients (21 female, 25 male) with histologically-confirmed brain lymphoma who underwent 18F-FDG PET/CT from vertex to the mid-thigh for initial staging were retrospectively evaluated. The PET images were analyzed visually and semi-quantitatively by measuring the maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio, lesion-to-blood pool SUVmax ratio and the tumor to normal brain uptake ratio (T/N ratio) and compared with epidemiological (age, sex, HIV infection) and morphological (tumor size, MRI appearance) characteristics. Thirty-eight patients (83%) had positive 18F-FDG PET/CT (average SUVmax was 15.6 ± 9.2; lesion-to-liver SUVmax ratio 5.8 ± 2.8; lesion-to-blood pool SUVmax ratio 7.1 ± 3.8, T/N ratio 3.1 ± 1.7) at the corresponding brain lesion; the remaining 8 (17%) were not 18F-FDG avid. 18F-FDG avidity was significantly associated with morphological appearance and tumor size and not correlated with other features. 18F-FDG PET/CT detected extracranial disease in two cases (4%) with negative bone marrow biopsies and CT. In conclusion, brain lymphomas are 18F-FDG avid in 83% of cases showing high 18F-FDG uptake and 18F-FDG avidity is correlated with tumor size and morphological appearance of the lesion. PET/CT helped to recognize extracranial disease in two patients.

Pulmonary mucosa-associated lymphoid tissue lymphoma: 18F-FDG PET/CT and CT findings in 28 patients

OBJECTIVE

The aim of the study was to evaluate the CT and fluorine-18-fluorodeoxyglucose positron emission tomography/CT (¹⁸F-FDG PET/CT) imaging findings of lung mucosa associated lymphoid tissue (MALT) lymphoma.

METHODS

28 patients with histologically confirmed pulmonary MALT lymphoma who underwent a chest CT and ¹⁸F-FDG PET/CT for staging were retrospectively analysed. The CT images were evaluated to determine morphological pattern of appearance, laterality, localization, number, size, presence of thoracic lymphadenopaties and secondary/combined findings. PET images were analysed visually and semi-quantitatively by measuring the maximum standardized uptake value (SUVmax), lesion-to-liver SUVmax ratio and lesion-to-blood pool SUVmax ratio. The relationship between qualitative and semi-quantitative features at ¹⁸F-FDG PET/CT and CT findings were also analysed.

RESULTS

A total of 57 pulmonary lesions were identified by CT: 37 areas of consolidation, 4 masses, 12 nodules and 4 ground-glass opacities. Solitary and multiple lesions were detected in 10 and 18 patients, respectively; among patients with multiple lesions, 16 were bilateral and 2 unilateral. ¹⁸F-FDG PET/CT revealed increased ¹⁸F-FDG uptake in 47/57 lesions, in 26/28 patients. 18F-FDG avidity was significantly associated only with tumour size.

CONCLUSIONS

Pulmonary MALT lymphoma is ¹⁸F-FDG avid in most cases and ¹⁸F-FDG avidity is correlated with tumour size. Consolidation is the most frequent morphological pattern of disease presentation. Advances in knowledge: This study demonstrated that lung MALT lymphoma are ¹⁸F-FDG avid in most cases depending on tumour size. Single or multiple areas of consolidation are the most common pattern of presentation of lung MALT lymphoma at CT.

Primary hepatic mucosa-associated lymphoid tissue lymphoma in a patient with no chronic liver disease: Case report

Extramarginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is a non-Hodgkin lymphoma of low-grade malignancy. The most common localization is the stomach, and the common nongastric sites are salivary glands, the skin, orbits, the conjunctiva, the lung, breasts, upper airways, other gastrointestinal sites, and the liver. Primary hepatic MALT lymphoma is a rare disease and the diagnostic can be challenging. The clinical presentation is nonspecific and may range from no symptoms to end-stage liver disease. The radiological aspect of hepatic lymphoma may indicate this diagnosis; however, the final diagnosis is made by hepatic biopsy. We report the case of a 47-year-old woman with no chronic liver disease, incidentally found with a focal liver mass at ultrasound examination. The only clinical symptom was fatigue. The blood tests were normal and tumoral markers were negative. Computed tomography and magnetic resonance imaging were performed. However, because the hepatic lesion was first described as a benign entity and, at second opinion, the suspicion of lymphoma was raised, the patient decided to undergo surgery first, without prior biopsy. The histopathologic analysis confirmed the diagnosis: hepatic MALT lymphoma positive for CD 20 and negative for CD 5, BCL6, cyclin D1, and CD 23. No lymph node involvement was noted and follow-up imaging with positron emission tomography-computed tomography did not show any other site of disease, thus confirming the diagnosis of primary hepatic MALT lymphoma. The aim of this paper was to highlight the imagistic features of primary hepatic lymphoma to contribute to the early diagnosis of this rare disease entity.