Clinical utility of ¹⁸F FDG-PET/CT in the detection of bone marrow disease in Hodgkin's lymphoma

Role of 2-(fluorine-18) Fluoro-2-deoxy-D-glucose Positron Emission Tomography/Computed Tomography in Initial Staging and Bone Marrow Involvement Prediction in Patients with Newly Diagnosed Lymphoma in Correlation with Bone Marrow Study

Background

Lymphoma is a common malignant proliferative disease in which bone marrow infiltration will upstage the disease and thus affect prognosis of the disease. As of now bone marrow biopsy is considered as a reference standard to find out bone marrow involvement in lymphoma. Performing an invasive and painful intervention in all newly diagnosed lymphoma patients is controversial. PET-CT is a non-invasive technique that gives functional information about the cells using the glucose metabolism. It can detect early bone marrow and extra medullary organ involvement which can lead to restaging of the disease. These advantages make PET-CT a valuable adjunct in diagnosis of lymphoma.

Aims and Objectives

Our study aims to evaluate the usefulness of 18 F-FDG PET-CT, a non-invasive, semi quantitative whole body imaging technique for detection of early bone marrow and extra medullary organ involvement in lymphoma patients which in turn can obviate the need for bone marrow study (BMS). The primary objective of study is to categorise FDG uptake in bone marrow as diffuse /unifocal /multifocal / no uptake and to correlate pattern of FDG uptake to bone marrow study. Our study also assesses the role of FDG PET/CT in staging of lymphoma.

Materials and Methods

Thirty patients with newly diagnosed lymphoma in the age group 18 to 75 years of both sexes within 3 months of diagnosis and who have not been started on any treatment was included in the study. Marrow uptake on FDG PET/CT has been categorized as diffuse, unifocal, multifocal and no uptake. Agreement between bone marrow study and FDG PET/CT has been assessed by reliability analysis using Cohen's kappa. Sensitivity, specificity, PPV, NPV of PET/CT in detecting marrow involvement have been calculated.

Results

The sensitivity, specificity, PPV, NPV and accuracy of 18 F-FDG PET-CT in detecting marrow involvement of lymphoma cases are 86.6%, 77.7%, 68.4%, 91.3% and 80.9% respectively. 18 F-FDG PET-CT detected bone marrow involvement in 86.6% (13 out of 15 total positive cases) cases of lymphoma which included both HL and NHL. Reliability analysis using Cohen's kappa is used to test the agreement between bone marrow study and 18F-FDG PET/CT. k value of 0.6 was obtained which showed a moderate agreement between bone marrow study and 18F-FDG PET/CT in marrow assessment.

Conclusion

18F-FDG PET/CT is a highly sensitive imaging modality which can pick up extra-nodal organ and BMI in patients with lymphoma and can upstage the disease and alter treatment strategies. PET-CT cannot completely replace the bone marrow study. However, being an invasive painful procedure, BMB can be avoided in cases with unifocal or multifocal marrow involvement on PET-CT.

The Diagnostic Accuracy of Bone Marrow Biopsy Versus PET/CT Scan in Identifying Bone Marrow Involvement in Diffuse Large B Cell Lymphoma Patients at a Cancer Hospital

Background It is of great importance to assess bone marrow involvement (BMI) in diffuse large B cell lymphoma (DLBCL) for staging, prognostic, and therapeutic purposes. The gold standard method used for the identification of bone marrow involvement is bone marrow biopsy (BMB), but it has certain drawbacks. In recent years, positron emission tomography/computed tomography (PET/CT) has become a highly effective method in the diagnosis and staging of lymphoma. Objective The objective of this study is to estimate the diagnostic accuracy of PET/CT in identifying bone marrow involvement in DLBCL patients in a cancer care hospital in Lahore, using BMB as a reference standard. Methods This descriptive cross-sectional study was conducted at the Department of Pathology of Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC) from January 1, 2013, to December 31, 2018. A retrospective data of 146 patients fulfilling the inclusion and exclusion criteria was retrieved from the hospital information system (HIS). The inclusion criteria include patients aged 18-80 years, of either gender, and with a confirmed diagnosis of DLBCL on tissue biopsy. The exclusion criteria include patients who had started chemotherapy or radiotherapy for DLBCL or were using granulocyte colony-stimulating factor (G-CSF) prior to their PET/CT scan. All patients underwent PET/CT and BMB, and the diagnostic accuracy of PET/CT was calculated, with BMB taken as the reference standard. Results The mean age of cases was 52.73 ± 16.27 years. There were 95 (65.1%) male and 51 (34.9%) female cases, with a high male-to-female ratio. In the present study, 32.19% of cases had bone marrow involvement on BMB, and 34.2% of cases had bone marrow involvement on PET/CT. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall diagnostic accuracy of PET/CT were found to be 93.61%, 93.93%, 88%, 96.88%, and 93.84%, respectively. Conclusion It is concluded that PET/CT scan has good sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy. So, it is suggested to choose this non-invasive technique because the presence of a disease in extra-medullary space can also be detected and the evaluation of bone marrow in the whole body can be performed. PET/CT scan is an effective imaging modality in the detection of bone marrow involvement in DLBCL patients, and its relative advantages over bone marrow biopsy might conclude this to be a preferred technique.

Comparison of Bone Marrow Involvement with Bone Marrow Biopsy and PET-CT and Evaluation of Any Effects on Survival in Patients Diagnosed with Hodgkin and Non-Hodgkin Lymphoma

We aimed to demonstrate whether PET-CT can replace bone marrow biopsy in detecting bone marrow involvement in subtypes of lymphoma. In addition, we aimed to also reveal whether there is a difference between the mean survival of patients with bone marrow involvement via PET-CT or biopsy. A total of 276 newly diagnosed lymphoma patients who underwent bone marrow biopsy and PET-CT prior to the treatment were scanned retrospectively. Bone marrow biopsy was used as the standard method to investigate the presence of bone marrow involvement in PET-CT. The relationship between bone marrow involvement and mean survival was compared using both methods. Out of the 276 patients, bone marrow involvement was detected with PET-CT and with biopsy, respectively in 56 patients (20.2%) and in 78 patients (28.2%). In terms of PET-CT's accuracy with respect to revealing bone marrow involvement, the highest rates were achieved respectively in diffuse large B cell lymphoma (DLBCL) (87.4%) and Hodgkin lymphoma (HL) (77.7%). In both the PET-CT and bone marrow biopsy methods, Overall Survival (OS) was found to be significantly shorter in patients with involvement than in patients without involvement (P: 0.001). PET-CT may replace bone marrow (BM) biopsy in detecting the bone marrow involvement in aggressive lymphoma subtypes such as DLBCL and HL. The presence of BM involvement at the time of diagnosis in both PET-CT and BM biopsy is associated with poor prognosis, and OS is short in this group.

Diagnostic performance of 18F-2-fluoro-2-deoxy-D-glucose PET/computerized tomography in identifying bone marrow infiltration in new patients with diffuse large B-cell lymphoma and Hodgkin lymphoma

OBJECTIVE

To compare between F-2-fluoro-2-deoxy-D-glucose PET/computerized tomography (F-FDG PET/CT) and routine iliac bone marrow biopsy (BMB) in assessment of bone marrow infiltration (BMI) in Hodgkin lymphoma and diffuse large B-cell lymphoma (DLBCL) patients at initial presentation.

PATIENTS AND METHODS

A retrospective analysis of 138 patients (50 Hodgkin lymphomas, 88 DLBCLs). The study included 70 males and 68 females with median age of 43 years. All patients underwent F-FDG PET/CT and iliac crest BMB before treatment. Any focal or patchy FDG uptake in the bone marrow, superior-to hepatic uptake was interpreted as abnormal with or without corresponding CT changes. Treatment response was evaluated clinically with each cycle of chemotherapy, radiologically after three cycles and at the end of treatment.

RESULTS

The overall diagnostic performance showed significant higher sensitivity of F-FDG PET/CT than that of BMB (73.9 versus 62.5%, P = 0.046), while the specificity was higher in BMB than in F-FDG PET/CT (100% in BMB versus 93.5% in F-FDG PET/CT). In Hodgkin lymphoma, sensitivity, negative predictive value (NPV) and accuracy were significantly higher in F-FDG PET/CT compared with BMB, being 87.5, 94.4 and 96% versus 50, 81 and 84% (P = 0.02, 0.03, 0.04, respectively). However, for DLBCL patients, almost comparable results were found between both tests in terms of sensitivity, NPV and accuracy (66.7, 83.9 and 81.8% versus 68.8, 84.9 and 88.6%, respectively). After PET/CT scan, 12 patients (8.6%) were upstaged to stage IV, eight of them were negative by BMB.

CONCLUSION

F-FDG PET/CT seemed to be an excellent diagnostic test in assessment of BMI at initial assessment and staging of Hodgkin lymphoma and DLBCL patients.

Predictive Value of FDG PET/CT Versus Bone Marrow Biopsy in Pediatric Lymphoma

PURPOSE

The aim of this study was to explore the positive predictive value and negative predictive value of FDG PET/CT. The prognostic impact of tumor burden of bone marrow infiltrates was diagnosed by FDG PET/CT at initial presentation.

METHODS

This retrospective study enrolled 140 pediatric patients with pathologically proven lymphoma (113 Hodgkin disease and 27 Non-Hodgkin lymphoma). All patients had pretherapy FDG PET/CT. Bone marrow biopsy (BMB), clinical, radiological, and follow-up data were also collected. The skeleton was divided into 8 segments, and a 5-point scoring system was used for assessment of BM infiltration burden.

RESULTS

Among the 140 lymphoma patients, FDG PET/CT revealed positive BM involvement in 41 patients; 2 of them were false-positive with negative BMB and regional MRI results. Positive predictive value was 95.1% for PET/CT compared with 100% with BMB. All patients diagnosed with positive BMI by BMB were detected by FDG PET/CT. On the contrary, BMB missed 25 patients (17.9%) with statistically significant difference. Negative predictive value was 100% for PET/CT compared with 80.2% for BMB (P < 0.05). FDG PET/CT upstaged 17.9% of the enrolled patients. Bone marrow involvement based on the 5-point scoring system was assessed. No significant difference was demonstrated in therapy outcome between patient with focal BMI (score 2) and extensive BMI (score 5; P = 0.06).

CONCLUSIONS

FDG PET/CT has optimum negative predictive value compared with BMB in detection of bone marrow infiltrations in pediatric lymphoma with upstaging cases missed with BMB. Prognostic impact of BMI based on the 5-point scoring system reveals that the main influence is presence or absence of BMI rather than its tumor burden.

Primary isolated bone marrow diffuse large B cell lymphoma with long-term complete remission

Secondary bone marrow involvement of non-Hodgkin's lymphoma (NHL) is relatively common. However, primary isolated bone marrow involvement in NHL which was successfully treated and remains in complete remission (CR) for a long-term duration without any relapse is extremely rare. We herein report a patient of primary bone marrow diffuse large B cell lymphoma (PBML/DLBCL) who presented a prolonged high-grade fever and systemic purpura due to severe thrombocytopenia. The patient was successfully treated with systemic chemotherapy by R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) and remains in CR at 8 years after the initial diagnosis. Review of the literature in PBML/DLBCL cases are also shown.

18F-FDG PET Response of Skeletal (Bone Marrow and Bone) Involvement After Induction Chemotherapy in Pediatric Hodgkin Lymphoma: Are Specific Response Criteria Required?

To determine whether the current ¹⁸F-FDG PET response criterion for skeletal involvement in Hodgkin lymphoma (HL) is suitable, we performed a systematic evaluation of the different types of skeletal involvement and their response on PET after 2 cycles of chemotherapy (PET-2). A secondary objective was to observe the influence of the initial uptake intensity (measured as qPET) and initial metabolic tumor volume (MTV) of skeletal lesions on the PET-2 response. Methods: The initial PET scans of 1,068 pediatric HL patients from the EuroNet-PHL-C1 trial were evaluated for skeletal involvement by central review. Three types of skeletal lesions were distinguished: PET-only lesions (those detected on PET only), bone marrow (BM) lesions (as confirmed by MRI or BM biopsy), and bone lesions. qPET and MTV were calculated for each skeletal lesion. All PET-2 scans were assessed for residual tumor activity. The rates of complete metabolic response for skeletal and nodal involvement on PET-2 were compared. Results: Of the 1,068 patients, 139 (13%) showed skeletal involvement (44 PET-only, 32 BM, and 63 bone). Of the 139 patients with skeletal involvement, 101 (73%) became PET-2-negative in the skeleton and 94 (68%) became PET-2-negative in the lymph nodes. The highest number of PET-2-negative scans in the skeleton was 42 (95%) in the 44 PET-only patients, followed by 22 skeletal lesions (69%) in the 32 BM patients and 37 (59%) in the 63 bone patients. Lesions that became PET-2-negative showed a lower initial median qPET (2.74) and MTV (2 cm³) than lesions that remained PET-2-positive (3.84 and 7 cm³, respectively). Conclusion: In this study with pediatric HL patients, the complete response rate for skeletal involvement on PET-2 was similar to that for nodal involvement. Bone flare seemed to be irrelevant. Overall, the current skeletal PET response criterion-comparison with the local skeletal background-is well suited. The initial qPET and MTV of skeletal lesions were predictive of the PET-2 result. Higher values for both parameters were associated with a worse PET-2 response.

Efficacy of 18F-2-fluoro-2-deoxy-D-glucose Positron Emission Tomography/Computerized Tomography for Bone Marrow Infiltration Assessment in the Initial Staging of Lymphoma

Objective:

Currently ¹⁸F-2-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computerized tomography (PET/CT) is being successfully used for staging and follow-up of Hodgkin’s lymphoma (HL) and non-Hodgkin’s lymphoma (NHL). Various studies have demonstrated that PET/CT effectively detects bone marrow involvement (BMI) and is concordant with bone marrow biopsy (BMB) findings, thus it is deemed as a complementary method. This study was aimed to evaluate ¹⁸F-FDG-PET/CT efficiency for detection of BMI in HL and NHL.

Methods:

The study included 172 lymphoma cases who were admitted to Akdeniz University Medical School Department of Nuclear Medicine for initial staging with PET/CT. Visual and semiquantitative assessments were performed for PET/CT scan findings of the cases. The maximum standard uptake (SUV_max) value was the quantitative parameter used for ¹⁸F-FDG-PET scan. In visual assessment, bone marrow metabolic activity that is greater than the liver was considered as pathologic. For semiquantitative assessment, regions of interest were drawn for SUV_max estimation, which included iliac crest in cases with diffusely increased metabolic activity and the highest activity area in cases with focal involvement. BMB was considered as the reference test.

Results:

On visual assessment of all the cases, PET/CT was found to yield 31% sensitivity and 85% specificity rate for detection of BMI. On visual assessment of HL cases, sensitivity rate was determined as 80%, and specificity as 78%, while in NHL cases the corresponding values were 24% and 90%, respectively. On semiquantitative assessment of HL cases, considering SUV_max≥4, sensitivity was found as 80% and specificity as 68%. In NHL patients, considering SUV_max≥3.2, sensitivity rate was detected as 65% and specificity as 58%.

Conclusion:

In this study, a moderately high concordance was observed between PET/CT and BMB findings. PET/CT appears to be a significant method for detecting BMI. Although PET/CT is not a substitute for BMB, we suggest it can be used as a guide to biopsy site and a complementary imaging technique for BMB.

Role of bone marrow biopsy in staging of patients with classical Hodgkin's lymphoma undergoing positron emission tomography/computed tomography

Several studies suggested that staging bone marrow biopsy (BMB) could be omitted in patients with classical Hodgkin's lymphoma (cHL) when a positron emission tomography/computed tomography (PET/CT) is performed at baseline.To address the concordance between BMB and PET/CT in the detection of bone marrow involvement (BMI) and the BMB role in determining the Ann Arbor stage, we retrospectively collected data on 1244 consecutive patients with cHL diagnosed from January 2007 to December 2013. One thousand eighty-five patients who had undergone both BMB and PET/CT were analyzed, comparing the Ann Arbor stage assessed with PET/CT only to that resulting from PET/CT combined with BMB.One hundred sixty-nine patients (16%) showed at least one focal skeletal lesion (FSL) at PET/CT evaluation. Only 55 patients had a positive BMB (5.1%); 34 of them presented at least one FSL at PET/CT. To the contrary, 895 out of 1030 patients with a negative BMB did not show any FSL (86.9%). Positive and negative predictive values of PET/CT for BMI were 20 and 98%, respectively; sensitivity and specificity were 62 and 87%, respectively. Fifty-four out of 55 patients with a positive BMB could have been evaluated as an advanced stage just after PET/CT; only one patient (0.1%) would have been differently treated without BMB.Our data showed a very high negative predictive value of PET/CT for BMI and a negligible influence of BMB on treatment planning, strengthening the recent indications that BMB could be safely omitted in cHL patients staged with PET/CT.

The Correlation Between Pre-treatment Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Parameters and Clinical Prognostic Factors in Pediatric Hodgkin Lymphoma

Objective:

To compare standardized uptake values (SUV) derived from pre-treatment 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging and clinical prognostic factors in pediatric patients with Hodgkin lymphoma (HL).

Methods:

Pre-treatment FDG PET/CT findings of 28 children with HL were evaluated in this retrospective study. Metabolic tumor volume (MTV), SUV_max normalized by weight (SUVw_eight), lean body mass (SUV_lbm), body surface area (SUV_bsa) and plasma glucose levels of tumors (SUV_glucose) were calculated using pre-treatment FDG PET/CT scan images. These metabolic parameters were correlated with clinical factors [age, sex, number of lymph node groups, presence of splenic involvement, bulky mediastinal disease, Ann Arbor stage, serum white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), serum albumin and hemoglobin levels].

Results:

SUV_bsa, SUV_lbm, SUV_weight, SUV_glucose and MTV were higher in patients with stage III-IV disease, bulky tumor and ≥3 lymph node groups (p<0.05). SUV_bsa and SUV_glucose were higher in patients with splenic involvement (p<0.05). There was no significant correlation between these metabolic parameters and sex, ESR, levels of albumin and WBC (p>0.05). SUV_bsa and SUV_lbm were higher in patients with anemia (p<0.05). Additionally, significant increases were detected in SUV_weight, MTV, and SUV_glucose with increasing age (p=0.005, p=0.027, and p=0.009, respectively). SUV_bsa and SUV_lbm had no significant correlation with age (p>0.05).

Conclusion:

Metabolic parameters derived from pre-treatment FDG PET/CT may have an important role in predicting high-risk disease in patients with HL. Also, SUV_bsa and SUV_lbm may be better markers than SUV_weight in the quantitative evaluation of FDG PET/CT scans in pediatric patients.

18F-FDG PET-CT imaging versus bone marrow biopsy in pediatric Hodgkin's lymphoma: a quantitative assessment of marrow uptake and novel insights into clinical implications of marrow involvement

OBJECTIVE

To evaluate whether positron emission tomography/computed tomography using fluorine-18 fluoro-deoxyglucose (¹⁸F-FDG PET-CT) predicts bone marrow involvement (BMI) in pediatric Hodgkin's lymphoma (pHL) with sufficient accuracy to supplant routine staging bone marrow biopsy (BMB), and to assess the clinical importance of marrow disease by comparing the prognosis of stage IV HL with BMI versus that without BMI.

METHODS

Data were retrospectively analyzed for all cases of pHL between July 2010 and June 2015 referred for staging ¹⁸F-FDG PET-CT scan and BMB. The reference standard was BMB. Stage IV patients were divided into three groups to compare their progression-free and overall survival: PET+ BMB-, PET+ BMB+, and PET- BMB-.

RESULTS

Of the 784 patients, 83.3% were male and 16.7% female, with age ranging from 2 to 18 years (mean 10.3 years). Among the total cases, 104 (13.3%) had BMI; of these, 100 were detected by PET imaging and 58 by BMB. BMB and ¹⁸F-FDG PET/CT scans were concordant for BMI detection in 728 patients (93%): positive concordance in 54 and negative in 674. Of the 56 discordant cases, four had a false-negative PET scans and were upstaged by BMB, 46 with focal uptake were PET/CT-positive and BMB-negative (not obtained from active sites), and six with diffuse uptake were false-positive on PET due to paraneoplastic marrow activation. The sensitivity, specificity, PPV, and NPV of PET for identifying BMI was 93.6, 94, 53, and 99.4% respectively. On quantitative assessment, mean iBM-SUV_max of bilateral iliac crests was significantly higher in those with BMI versus those without (p < 0.05).

CONCLUSIONS

¹⁸F-FDG PET-CT imaging is more sensitive than BMB for BMI detection in pHL staging. BMB should be limited to those with normal marrow uptake in the presence of poor risk factors or those with diffusely increased uptake to exclude marrow involvement in the background of reactive marrow.

Prognostic Value of Bone Marrow Tracer Uptake Pattern in Baseline PET Scans in Hodgkin Lymphoma: Results from an International Collaborative Study

PET/CT-ascertained bone marrow involvement (BMI) constitutes the single most important reason for upstaging by PET/CT in Hodgkin lymphoma (HL). However, BMI assessment in PET/CT can be challenging. This study analyzed the clinicopathologic correlations and prognostic meaning of different patterns of bone marrow (BM) ¹⁸F-FDG uptake in HL. Methods: One hundred eighty newly diagnosed early unfavorable and advanced-stage HL patients, all scanned at baseline and after 2 adriamycin-bleomycin-vinblastine-dacarbazine (ABVD) courses with ¹⁸F-FDG PET, enrolled in 2 international studies aimed at assessing the role of interim PET scanning in HL, were retrospectively included. Patients were treated with ABVD × 4-6 cycles and involved-field radiation when needed, and no treatment adaptation on interim PET scanning was allowed. Two masked reviewers independently reported the scans. Results: Thirty-eight patients (21.1%) had focal lesions (fPET⁺), 10 of them with a single (unifocal) and 28 with multiple (multifocal) BM lesions. Fifty-three patients (29.4%) had pure strong (>liver) diffuse uptake (dPET⁺) and 89 (48.4%) showed no or faint (≤liver) BM uptake (nPET⁺). BM biopsy was positive in 6 of 38 patients (15.7%) for fPET⁺, in 1 of 53 (1.9%) for dPET⁺, and in 5 of 89 (5.6%) for nPET⁺ dPET⁺ was correlated with younger age, higher frequency of bulky disease, lower hemoglobin levels, higher leukocyte counts, and similar diffuse uptake in the spleen. Patients with pure dPET⁺ had a 3-y progression-free survival identical to patients without any ¹⁸F-FDG uptake (82.9% and 82.2%, respectively, P = 0.918). However, patients with fPET+ (either unifocal or multifocal) had a 3-y progression-free survival significantly inferior to patients with dPET+ and nPET+ (66.7% and 82.5%, respectively, P = 0.03). The κ values for interobserver agreement were 0.84 for focal uptake and 0.78 for diffuse uptake. Conclusion: We confirmed that ¹⁸F-FDG PET scanning is a reliable tool for BMI assessment in HL, and BM biopsy is no longer needed for routine staging. Moreover, the interobserver agreement for BMI in this study proved excellent and only focal ¹⁸F-FDG BM uptake should be considered as a harbinger of HL.

(18) F-FDG PET-CT and trephine biopsy assessment of bone marrow involvement in lymphoma

The ability of positron emission tomography-computerized tomography (PET-CT) to accurately detect bone marrow involvement (BMI) has been suggested in Hodgkin lymphoma (HL) and diffuse large B-cell lymphoma (DLBCL), but its abilities in other histologies is less established. The aim of this retrospective study was to confirm the role of PET-CT in detecting BMI in DLBCL and HL, and to explore its usefulness in other subtypes. Of the 149 newly diagnosed patients, common subtypes included DLBCL, follicular lymphoma (FL) and HL. In DLBCL, the sensitivity and specificity of PET-CT at diagnosis were 75% and 92%. In FL, the sensitivity and specificity of PET-CT were 67% and 85% at diagnosis, and 73% and 89% at relapse. In HL, the sensitivity and specificity were 100% and 74%. PET-CT was able to detect BMI in patients with negative biopsies. Most of the patients in which PET-CT failed to identify BMI were already advanced stage by imaging. In this analysis, PET-CT was highly accurate for detecting BMI at diagnosis in DLBCL and HL and highly specific in FL at diagnosis and relapse. Results also suggested the diagnostic advantage of PET-CT over bone marrow biopsy in detecting BMI. Prospective evaluation is necessary and may eliminate biopsies in future patients.

Multimodality imaging of osseous involvement In haematological malignancies

The purpose of this article is to provide a comprehensive review of the imaging features of osseous involvement in haematological malignancies. Osseous involvement can be seen in various haematological malignancies including lymphomas, plasma cell neoplasms, leukaemias and myeloproliferative neoplasms. Imaging plays a crucial role in initial diagnosis, staging and in the assessment of treatment response in these patients.

Opportunities and limitations of bone marrow biopsy and bone marrow FDG-PET in lymphoma

Bone marrow involvement in lymphoma may have prognostic and therapeutic consequences. Bone marrow biopsy (BMB) is the established method for the evaluation of the bone marrow. (18)F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) plays an important role in lymphoma staging, but its value in the assessment of the bone marrow and whether it can replace BMB is still a topic of debate and investigation. The purpose of this scientific communication is to provide an evidence-based overview about the opportunities and limitations of BMB and FDG-PET in the evaluation of the bone marrow in patients with lymphoma. This article first reviews the basic properties, opportunities and limitations of BMB and bone marrow FDG-PET, and then focuses on the clinical utility of BMB and bone marrow FDG-PET in three major lymphoma subtypes including Hodgkin lymphoma, diffuse large B-cell lymphoma, and follicular lymphoma.

Role of 2-Deoxy-2-[18F]-fluoro-d-glucose-PET/Computed Tomography in Lymphoma

The role of PET and PET/computed tomography (CT) has evolved significantly in the last few decades. 2-Deoxy-2-[18F]-fluoro-d-glucose (FDG)-PET/CT is now an integral part of the management of patients with lymphoma. FDG-PET/CT at the time of initial staging can help in appropriate staging of the patients. Both interim and end-of-therapy PETs have significant prognostic value in patients with Hodgkin lymphoma and aggressive non-Hodgkin lymphoma and more accurately assess for the presence of residual malignancy than anatomic imaging. The impact of interim FDG-PET/CT on risk-adapted strategies is an area of active investigation and the results of ongoing clinical trials will be informative.

Utility of bone marrow aspiration and biopsy in initial staging of Ewing sarcoma

BACKGROUND

The current standard of care for initial staging of pediatric Ewing sarcoma (EWS) patients is to obtain a bilateral bone marrow aspiration and biopsy (BMAB). The incidence of bone marrow (BM) disease in patients deemed non-metastatic by conventional and metabolic imaging and the concordance of BM positivity with other clinical characteristics are not well established.

PROCEDURE

This study is a multi-institutional retrospective review of newly diagnosed EWS patients less than 40 years of age with initial staging that included imaging and BMAB.

RESULTS

A total of 116 patients were eligible with 85 patients considered non-metastatic and 31 considered metastatic by imaging. None of the 85 patients with non-metastatic disease were BMAB positive (0%; 95% CI: 0-4.2%); 13 of the 31 patients with metastases were BMAB positive (41.9%; 95% CI: 24.5-60.9%). Primary tumor size was significantly higher in patients with metastases (P = 0.017). Bone metastasis by imaging had high correlation with BMAB positivity (P = 0.0002). In addition, the number of bony metastatic sites was significantly higher in patients with a positive BMAB as compared to those with a negative BMAB (median 3.5 and 0.0, respectively; P < 0.001).

CONCLUSIONS

BMAB may not be required for initial staging of pediatric and young adult EWS patients deemed non-metastatic by imaging. In patients with metastatic disease, there is a high correlation of BM involvement with multiple bone metastases.

Current role of FDG PET/CT in lymphoma

The management approach in Hodgkin's (HL) and high-grade non-Hodgkin's lymphomas (NHL) has shifted towards reducing the toxicity and long-term adverse effects associated with treatment while maintaining favorable outcomes in low-risk patients. The success of an individualized treatment strategy depends largely on accurate diagnostic tests both at staging and during therapy. In this regard, positron emission tomography (PET) using fluorodeoxyglucose (FDG) with computed tomography (CT) has proved effective as a metabolic imaging tool with compelling evidence supporting its superiority over conventional modalities, particularly in staging and early evaluation of response. Eventually, this modality was integrated into the routine staging and restaging algorithm of lymphomas. This review will summarize the data on the proven and potential utility of PET/CT imaging for staging, response assessment, and restaging, describing current limitations of this imaging modality.

Systematic review and meta-analysis on the diagnostic performance of FDG-PET/CT in detecting bone marrow involvement in newly diagnosed Hodgkin lymphoma: is bone marrow biopsy still necessary?

BACKGROUND

This study aimed to systematically review and meta-analyze published data on the diagnostic performance of (18)F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) in detecting bone marrow involvement in newly diagnosed Hodgkin lymphoma, and to determine whether FDG-PET/CT can replace blind bone marrow biopsy (BMB) in these patients.

PATIENTS AND METHODS

The PubMed/Medline and Embase databases were systematically searched for relevant studies. Methodological quality of each study was assessed. Sensitivities and specificities of FDG-PET/CT in individual studies were calculated and underwent meta-analysis with a random effects model. A summary receiver operating characteristic curve (sROC) was constructed with the Moses-Shapiro-Littenberg method. The weighted summary proportion of FDG-PET/CT-negative patients with a positive BMB among all cases was calculated under the fixed effects model.

RESULTS

Nine eligible studies, comprising a total of 955 patients with newly diagnosed Hodgkin lymphoma, were included. Overall, the studies were of moderate methodological quality. The sensitivity and specificity of FDG-PET/CT for the detection of bone marrow involvement ranged from 87.5% to 100% and from 86.7% to 100%, respectively, with pooled estimates of 96.9% [95% confidence interval (CI) 93.0% to 99.0%] and 99.7% (95% CI 98.9% to 100%), respectively. The area under the sROC curve was 0.9860. The weighted summary proportion of FDG-PET/CT-negative patients with a positive BMB among all cases was 1.1% (95% CI 0.6% to 2.0%).

CONCLUSION

Although the methodological quality of studies that were included in this systematic review and meta-analysis was moderate, the current evidence suggests that FDG-PET/CT may be an appropriate method to replace BMB in newly diagnosed Hodgkin lymphoma.

Value of 18F-FDG PET versus iliac biopsy in the initial evaluation of bone marrow infiltration in the case of Hodgkin's disease: a meta-analysis

OBJECTIVE

We carried out a meta-analysis to evaluate the performance of 2-deoxy-2-[(18)F]fluoro-D-glucose ((18)F-FDG) PET and PET/CT against bone marrow biopsy (BMB) in the initial diagnosis of bone marrow infiltration (BMI) in patients with Hodgkin's disease (HD).

MATERIALS AND METHODS

Retrospective and prospective studies with direct comparison of (18)F-FDG PET with BMB in the initial evaluation of BMI in HD were included. Seven eligible studies were included in the meta-analysis comprising a total of 687 patients.

RESULTS

Both (18)F-FDG PET and BMB had excellent specificity in detecting BMI. However, (18)F-FDG PET had excellent pooled sensitivity (94.5%; 95% confidence interval: 89.0-97.8%) in detecting BMI in the initial staging of HD patients, whereas the pooled sensitivity of iliac BMB was very poor (39.4%; 95% confidence interval: 30.8-48.4%). The diagnostic odds ratio, a measure of the overall diagnostic power of the test, was much higher for PET (pooled value of 1591) than for iliac BMB (pooled value of 137).

CONCLUSION

(18)F-FDG PET significantly outperforms iliac BMB in the detection of BMI in the initial staging of HD patients and therefore should be used as a first-line study. Iliac BMB has low sensitivity and a high rate of false-negative findings. Thus, a negative BMB finding cannot rule out marrow involvement in HD patients on initial staging.

PET scan integration in lymphoma management

SUMMARY Despite a marked improvement in lymphoma treatment outcome, current prognostic models, relying on a pretreatment set of static clinical variables, appear unable to support a risk-adapted therapeutic strategy. On the other hand, functional imaging with 18F-fluoro-2-deoxy-D-glucose (FDG)-PET proved to be a reliable tool to dynamically assess tumor FDG uptake changes during and after treatment. In this article we aim to review the prognostic value of FDG-PET in all the stages of Hodgkin’s and non-Hodgkin’s lymphoma management, without the intent to address the diagnostic value of PET or to replace available consensus guidelines. In particular we focused on two critical issues: the cost–effectiveness of PET in the overall strategy of lymphoma diagnosis and treatment; and ongoing clinical trials adopting an interim PET-based strategy to modulate treatment intensity based on PET results. Finally, new trends in multimodality imaging, as well as in new radiopharmaceutical tracers, are briefly reviewed.

Diagnostic role of 18F-fluorodeoxyglucose positron emission tomography for follicular lymphoma with gastrointestinal involvement

AIM: To investigate the capacity for 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) to evaluate patients with gastrointestinal lesions of follicular lymphoma.

METHODS: This retrospective case series consisted of 41 patients with follicular lymphoma and gastrointestinal involvement who underwent 18F-FDG-PET and endoscopic evaluations at ten different institutions between November 1996 and October 2011. Data for endoscopic, radiological, and biological examinations performed were retrospectively reviewed from clinical records. A semi-quantitative analysis of 18F-FDG uptake was performed for each involved area by calculating the maximum standardized uptake value (SUVmax). Based on the positivity of 18F-FDG uptake in the gastrointestinal lesions analyzed, patients were subdivided into two groups. To identify potential predictive factors for 18F-FDG positivity, these two groups were compared with respect to gender, age at diagnosis of lymphoma, histopathological grade, pattern of follicular dendritic cells, mitotic rate, clinical stage, soluble interleukin-2 receptor levels detected by 18F-FDG-PET, lactate dehydrogenase (LDH) levels, hemoglobin levels, bone marrow involvement, detectability of gastrointestinal lesions by computed tomography (CT) scanning, and follicular lymphoma international prognostic index (FLIPI) risk.

RESULTS: Involvement of follicular lymphoma in the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum was identified in 1, 34, 6, 3, 2, 3, and 6 patients, respectively. No patient had esophageal involvement. In total, 19/41 (46.3%) patients exhibited true-positive 18F-FDG uptake in the lesions present in their gastrointestinal tract. In contrast, false-negative 18F-FDG uptake was detected in 24 patients (58.5%), while false-positive 18F-FDG uptake was detected in 5 patients (12.2%). In the former case, 2/19 patients had both 18F-FDG-positive lesions and 18F-FDG-negative lesions in the gastrointestinal tract. In patients with 18F-FDG avidity, the SUVmax value of the involved gastrointestinal tract ranged from 2.6 to 17.4 (median: 4.7). For the 18F-FDG-negative (n = 22) and -positive (n = 19) groups, there were no differences in the male to female ratios (10/12 vs 4/15, P = 0.186), patient age (63.6 ± 2.4 years vs 60.1 ± 2.6 years, P = 0.323), presence of histopathological grade 1 vs 2 (20/2 and 17/2, P = 1.000), follicular dendritic cell pattern (duodenal/nodal: 13/5 vs 10/3, P = 1.000), mitotic rate (low/partly high, 14/1 vs 10/3, P = 0.311), clinical stage according to the Ann Arbor system (stages IE and IIE/other, 15/7 vs 15/4, P = 0.499), clinical stage according to the Lugano system (stages I and II-1/other, 14/8 vs 14/5, P = 0.489), soluble interleukin-2 receptor levels (495 ± 78 vs 402 ± 83, P = 0.884), LDH levels (188 ± 7 vs 183 ± 8, P = 0.749), hemoglobin levels (13.5 ± 0.3 vs 12.8 ± 0.4, P = 0.197), bone marrow involvement (positive/negative, 1/8 vs 1/10, P = 1.000), detectability by CT scanning (positive/negative, 1/16 vs 4/13, P = 0.335), and FLIPI risk (low risk/other, 16/6 vs 13/6, P = 0.763), respectively in each case.

CONCLUSION: These findings indicate that it is not feasible to predict 18F-FDG-avidity. Therefore, 18F-FDG-PET scans represent a complementary modality for the detection of gastrointestinal involvements in follicular lymphoma patients, and surveillance of the entire gastrointestinal tract by endoscopic examinations is required.

Routine bone marrow biopsy has little or no therapeutic consequence for positron emission tomography/computed tomography-staged treatment-naive patients with Hodgkin lymphoma

PURPOSE

To investigate whether bone marrow biopsy (BMB) adds useful information to [(18)F]fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) staging in patients with Hodgkin lymphoma (HL).

PATIENTS AND METHODS

Newly diagnosed patients with HL undergoing a pretherapeutic staging that encompasses both PET/CT and BMB were included in this retrospective study. The pattern of skeletal FDG uptake was categorized as uni-, bi-, or multifocal (≥ three lesions). Clinical stage, risk assessment, and treatment plan were determined with and without the contribution of BMB results according to the Ann Arbor classification and the guidelines from the German Hodgkin Study Group.

RESULTS

A total of 454 patients with HL were included of whom 82 (18%) had focal skeletal PET/CT lesions and 27 (6%) had positive BMB. No patients with positive BMB were assessed as having stage I to II disease by PET/CT staging. BMB upstaged five patients, assessed as being stage III before BMB; none of the 454 patients would have been allocated to another treatment on the basis of BMB results. Focal skeletal PET/CT lesions identified positive and negative BMBs with a sensitivity and specificity of 85% and 86%, respectively. The positive and negative predictive values of focal skeletal PET/CT lesions for BMB results were 28% and 99%, respectively.

CONCLUSION

A consistent finding of this study was the absence of positive BMBs in PET/CT-assessed stage I to II disease. The omission of staging BMB would not have changed the risk assessment or treatment strategy in this cohort of 454 newly diagnosed patients with HL.