Human Epidermal Growth Factor Receptor 2-Targeting [68Ga]Ga-ABY-025 PET/CT Predicts Early Metabolic Response in Metastatic Breast Cancer.

Imaging using the human epidermal growth factor receptor 2 (HER2)-binding tracer 68Ga-labeled ZHER2:2891-Cys-MMA-DOTA ([68Ga]Ga-ABY-025) was shown to reflect HER2 status determined by immunohistochemistry and in situ hybridization in metastatic breast cancer (MBC). This single-center open-label phase II study investigated how [68Ga]Ga-ABY-025 uptake corresponds to biopsy results and early treatment response in both primary breast cancer (PBC) planned for neoadjuvant chemotherapy and MBC. Methods: Forty patients with known positive HER2 status were included: 19 with PBC and 21 with MBC (median, 3 previous treatments). [68Ga]Ga-ABY-025 PET/CT, [18F]F-FDG PET/CT, and core-needle biopsies from targeted lesions were performed at baseline. [18F]F-FDG PET/CT was repeated after 2 cycles of therapy to calculate the directional change in tumor lesion glycolysis (Δ-TLG). The largest lesions (up to 5) were evaluated in all 3 scans per patient. SUVs from [68Ga]Ga-ABY-025 PET/CT were compared with the biopsied HER2 status and Δ-TLG by receiver operating characteristic analyses. Results: Trial biopsies were HER2-positive in 31 patients, HER2-negative in 6 patients, and borderline HER2-positive in 3 patients. The [68Ga]Ga-ABY-025 PET/CT cutoff SUVmax of 6.0 predicted a Δ-TLG lower than -25% with 86% sensitivity and 67% specificity in soft-tissue lesions (area under the curve, 0.74 [95% CI, 0.67-0.82]; P = 0.01). Compared with the HER2 status, this cutoff resulted in clinically relevant discordant findings in 12 of 40 patients. Metabolic response (Δ-TLG) was more pronounced in PBC (-71% [95% CI, -58% to -83%]; P < 0.0001) than in MBC (-27% [95% CI, -16% to -38%]; P < 0.0001), but [68Ga]Ga-ABY-025 SUVmax was similar in both with a mean SUVmax of 9.8 (95% CI, 6.3-13.3) and 13.9 (95% CI, 10.5-17.2), respectively (P = 0.10). In multivariate analysis, global Δ-TLG was positively associated with the number of previous treatments (P = 0.0004) and negatively associated with [68Ga]Ga-ABY-025 PET/CT SUVmax (P = 0.018) but not with HER2 status (P = 0.09). Conclusion: [68Ga]Ga-ABY-025 PET/CT predicted early metabolic response to HER2-targeted therapy in HER2-positive breast cancer. Metabolic response was attenuated in recurrent disease. [68Ga]Ga-ABY-025 PET/CT appears to provide an estimate of the HER2 expression required to induce tumor metabolic remission by targeted therapies and might be useful as an adjunct diagnostic tool.

Comparison of 68Ga-PSMA PET/CT with fluoride PET/CT for detection of bone metastatic disease in prostate cancer.

BACKGROUND: 18F-NaF positron emission tomography/computed tomography (fluoride PET/CT) is considered the most sensitive technique to detect bone metastasis in prostate cancer (PCa). 68Ga-PSMA-11 (PSMA) PET/CT is increasingly used for staging of PCa. This study primarily aimed to compare the diagnostic performance of fluoride PET/CT and gallium-based PSMA PET/CT in identifying bone metastasis followed by a comparison of PSMA PET/CT with contrast-enhanced CT (CE-CT) in identifying soft tissue lesions as a secondary objective. METHODS: Twenty-eight PCa patients with high suspicion of disseminated disease following curative treatment were prospectively evaluated. PET/CT examinations using fluoride and PSMA were performed. All suspicious bone lesions were counted, and the tracer uptake was measured as standardized uptake values (SUV) for both tracers. In patients with multiple findings, ten bone lesions with highest SUVmax were selected from which identical lesions from both scans were considered for direct comparison of SUVmax. Soft tissue findings of local and lymph node lesions from CE-CT were compared with PSMA PET/CT. RESULTS: Both scans were negative for bone lesions in 7 patients (25%). Of 699 lesions consistent with skeletal metastasis in 21 patients on fluoride PET/CT, PSMA PET/CT identified 579 lesions (83%). In 69 identical bone lesions fluoride PET/CT showed significantly higher uptake (mean SUVmax: 73.1 ± 36.8) compared to PSMA PET/CT (34.5 ± 31.4; p < 0.001). Compared to CE-CT, PSMA PET/CT showed better diagnostic performance in locating local (96% vs 61%, p = 0.004) and lymph node (94% vs 46%, p < 0.001) metastasis. CONCLUSION: In this prospective comparative study, PSMA PET/CT detected the majority of bone lesions that were positive on fluoride PET/CT. Further, this study indicates better diagnostic performance of PSMA PET/CT to locate soft tissue lesions compared to CE-CT.

The Role of Nuclear Medicine Imaging with 18F-FDG PET/CT, Combined 111In-WBC/99mTc-Nanocoll, and 99mTc-HDP SPECT/CT in the Evaluation of Patients with Chronic Problems after TKA or THA in a Prospective Study.

BACKGROUND: The aim of this prospective study was to assess the diagnostic value of nuclear imaging with 18F-FDG PET/CT (FDG PET/CT), combined 111In-WBC/99mTc-Nanocoll, and 99mTc-HDP SPECT/CT (dual-isotope WBC/bone marrow scan) for patients with chronic problems related to knee or hip prostheses (TKA or THA) scheduled by a structured multidisciplinary algorithm. MATERIALS AND METHODS: Fifty-five patients underwent imaging with 99mTc-HDP SPECT/CT (bone scan), dual-isotope WBC/bone marrow scan, and FDG PET/CT. The final diagnosis of prosthetic joint infection (PJI) and/or loosening was based on the intraoperative findings and microbiological culture results and the clinical follow-up. RESULTS: The diagnostic performance of dual-isotope WBC/bone marrow SPECT/CT for PJI showed a sensitivity of 100% (CI 0.74-1.00), a specificity of 97% (CI 0.82-1.00), and an accuracy of 98% (CI 0.88-1.00); for PET/CT, the sensitivity, specificity, and accuracy were 100% (CI 0.74-1.00), 71% (CI 0.56-0.90), and 79% (CI 0.68-0.93), respectively. CONCLUSIONS: In a standardized prospectively scheduled patient group, the results showed highly specific performance of combined dual-isotope WBC/bone marrow SPECT/CT in confirming chronic PJI. FDG PET/CT has an appropriate accuracy, but the utility of its use in the clinical diagnostic algorithm of suspected PJI needs further evidence.

Prospective data-driven respiratory gating of [68Ga]Ga-DOTATOC PET/CT.

AIM: The aim of this prospective study was to evaluate a data-driven gating software's performance, in terms of identifying the respiratory signal, comparing [68Ga]Ga-DOTATOC and [18F]FDG examinations. In addition, for the [68Ga]Ga-DOTATOC examinations, tracer uptake quantitation and liver lesion detectability were assessed. METHODS: Twenty-four patients with confirmed or suspected neuroendocrine tumours underwent whole-body [68Ga]Ga-DOTATOC PET/CT examinations. Prospective DDG was applied on all bed positions and respiratory motion correction was triggered automatically when the detected respiratory signal exceeded a certain threshold (R value ≥ 15), at which point the scan time for that bed position was doubled. These bed positions were reconstructed with quiescent period gating (QPG), retaining 50% of the total coincidences. A respiratory signal evaluation regarding the software's efficacy in detecting respiratory motion for [68Ga]Ga-DOTATOC was conducted and compared to [18F]FDG data. Measurements of SUVmax, SUVmean, and tumour volume were performed on [68Ga]Ga-DOTATOC PET and compared between gated and non-gated images. RESULTS: The threshold of R ≥ 15 was exceeded and gating triggered on mean 2.1 bed positions per examination for [68Ga]Ga-DOTATOC as compared to 1.4 for [18F]FDG. In total, 34 tumours were evaluated in a quantitative analysis. An increase of 25.3% and 28.1%, respectively, for SUVmax (P < 0.0001) and SUVmean (P < 0.0001), and decrease of 21.1% in tumour volume (P < 0.0001) was found when DDG was applied. CONCLUSIONS: High respiratory signal was exclusively detected in bed positions where respiratory motion was expected, indicating reliable performance of the DDG software on [68Ga]Ga-DOTATOC PET/CT. DDG yielded significantly higher SUVmax and SUVmean values and smaller tumour volumes, as compared to non-gated images.

Venous thromboembolism in epithelial ovarian cancer. A prospective cohort study.

OBJECTIVE: To determine the incidence of symptomatic and incidental venous thromboembolism (VTE) at time of diagnosis and throughout the first year, in patients with suspected epithelial ovarian cancer (EOC). METHODS: Patients were recruited consecutively in the gynecological outpatient clinic at Aalborg University Hospital, Denmark from December 2014 to May 2017. All patients underwent a whole leg compression ultrasound scan (CUS), Computed Tomography (CT) of the thorax in arterial phase at time of inclusion, to be able to diagnose deep vein thrombosis (DVT) and pulmonary embolism (PE), respectively. Patients were followed and systematically screened for VTE throughout 12 months. RESULTS: Ninety-seven patients with suspected EOC were enrolled in the study and followed up. Within the group of EOC patients (N = 53) eleven were diagnosed with VTE during the first year from EOC diagnosis, the incidence of VTE at time of diagnosis was low (2/53-3.8%). No patients with borderline or benign ovarian neoplasms were diagnosed with VTE. One EOC patient had a VTE during the postoperative period and further eight EOC patients were diagnosed with VTE within the first year, during periods undergoing non-surgical cancer treatment. Median time to VTE was 87 days. CONCLUSIONS: The one year cumulative incidence of VTE in EOC patients was 20.8% with a low incidence at time of diagnosis. A substantial number of VTE cases (73%) appeared during periods of non-surgical oncologic treatment. Future research should focus on risk factors and timing of VTE in EOC patients, as this could have important implications for future prophylaxis guidelines.

Z-score maps from low-dose 18F-FDG PET of the brain in neurodegenerative dementia.

Neuroimaging is a central part of diagnostic work-up of patients with suspected neurodegenerative disease. FDG-PET can reveal pathological changes earlier and more reliably than morphological imaging. Diagnostic accuracy can be improved by constructing 3D SSP Z-score maps, showing patterns of significant deficits. During FDG-PET, the subject receives a moderate but not insignificant dose of ionizing radiation, and a dose reduction with retained image quality is desirable. With lower dose, repeated examinations can become a useful tool for monitoring disease progress and potential effects of disease-modifying interventions. The aim of this study was to evaluate Z-maps created from low-dose and normal-dose FDG-PET of the brain, with quantitative and qualitative methods. Nine patients with neurodegenerative disorders were prospectively enrolled and nine age-matched controls were recruited through advertising. All subjects (n=18) underwent two FDG-PET scans on separate occasions; a routine and a low-dose scan. The routine dosage of FDG was 3 MBq/kg, and low dosage was 0.75 MBq/kg. 3D-SSP images showing Z-scores of < -1.96 were created from 10-minute summations. The study was comprised of a quantitative part comparing the Z-scores, and a qualitative part where experienced nuclear medicine specialists visually assessed the images. Regarding the quantitative part, Bland-Altman analysis showed a slight constant bias (0.206). Regarding qualitative discrimination between patients and controls, the performance between normal- and low-dose were equal, both showing 72% sensitivity, 83% specificity and 78% accuracy. In this study, visual assessment of 3D-SSP Z-score maps from low-dose FDG-PET provided diagnostic information highly comparable to normal-dose, with minor quantitative discrepancies.

The Frequency of Focal Thyroid Incidental Findings and Risk of Malignancy Detected by 18F-Fluorodeoxyglucose Positron Emission Tomography in an Iodine Deficient Population.

Incidental focal uptake of 18F-fluorodeoxyglucose (FDG) in the thyroid on positron emission tomography (PET/CT) is rare but often associated with malignancy. The epidemiology of thyroid incidentalomas has only to some extent been described in countries with iodine deficiency. Here we report data from Denmark, a country with known iodine deficiency and wide access to PET/CT. All FDG PET/CT comprising the head and neck region, during 2014, were retrospectively reviewed, and patients with focal FDG uptake in the thyroid gland were identified. A total of 2451 patients had an FDG PET/CT of which 59 (2.4%) patients presented with FDG-avid focal lesions in the thyroid gland. Among the 59 patients with FDG-avid lesions, 33 patients (56%) received work up with ultrasound, thyroid technetium scintigraphy, fine needle aspiration, and/or histology of which 20 patients had a conclusive pathology report. Ten patients with FDG-avid lesions were identified with thyroid malignancy. The risk of thyroid malignancy was 16.9% among patient with incidental FDG-avid thyroid lesions. Our findings indicated a similar frequency of FDG thyroid incidentalomas and malignancy rates in an iodine deficient population compared to summary data from prior studies, studies mostly performed in geographical areas of normal or excess iodine supplementation.

[Primary aneurysmal bone cyst of the maxillary sinus].

This case report describes a primary aneurysmal bone cyst in the maxillary sinus of a 50-year-old woman. She had nonspecific symptoms through four years of tearing, muscle tension in the face and neck as well as a sense of altered sound of speech. A magnetic resonance imaging of the facial skeleton showed multiple cystic processes with liquid mirror in nearly all large cysts. Histology confirmed the diagnosis of a rare aneurysmal bone cyst, and the operation was done by endoscopic resection. At the one-month post-operative control there was no recurrence.

Outcome prediction by extranodal involvement, IPI, R-IPI, and NCCN-IPI in the PET/CT and rituximab era: A Danish-Canadian study of 443 patients with diffuse-large B-cell lymphoma.

18F-fluorodeoxyglucose PET/CT (PET/CT) is the current state-of-the-art in the staging of diffuse large B-cell lymphoma (DLBCL) and has a high sensitivity for extranodal involvement. Therefore, reassessment of extranodal involvement and the current prognostic indices in the PET/CT era is warranted. We screened patients with newly diagnosed DLBCL seen at the academic centers of Aalborg, Copenhagen, and British Columbia for eligibility. Patients that had been staged with PET/CT and treated with R-CHOP(-like) 1(st) line treatment were retrospectively included. In total 443 patients met the inclusion criteria. With a median follow-up of 2.4 years, the 3-year overall (OS) and progression-free survival (PFS) were 73% and 69%, respectively. The Ann Arbor classification had no prognostic impact in itself with the exception of stage IV disease (HR 2.14 for PFS, P<0.01). Extranodal involvement was associated with a worse outcome in general, and in particular for patients with involvement of >2 extranodal sites, including HR 7.81 (P < 0.001) for PFS for >3 sites. Bone/bone marrow involvement was the most commonly involved extranodal site identified by PET/CT (29%) and was associated with an inferior PFS and OS. The IPI, R-IPI, and NCCN-IPI were predictive of PFS and OS, and the two latter could identify a very good prognostic subgroup with 3-year PFS and OS of 100%. PET/CT-ascertained extranodal involvement in DLBCL is common and involvement of >2 extranodal sites is associated with a dismal outcome. The IPI, R-IPI, and NCCN-IPI predict outcome with high accuracy.

Utility of interim and end-of-treatment PET/CT in peripheral T-cell lymphomas: A review of 124 patients.

According to the updated guidelines for imaging in lymphoma, 18F-FDG positron emission tomography/computed tomography (PET/CT) is recommended for staging and evaluation of treatment response in FDG-avid lymphomas. The purpose of the study was to evaluate the utility of PET/CT in nodal peripheral T-cell lymphomas (PTCL). Patients with newly diagnosed nodal PTCL (peripheral T-cell lymphoma NOS, anaplastic large-cell lymphoma, or angioimmunoblastic T-cell lymphoma) seen at five Danish hematology centers during the period 2006 to 2012 were included, if they had been pretherapeutically staged with PET/CT. Medical records were reviewed for baseline clinical and follow-up information. Staging, interim (I-PET), and end-of-treatment PET/CT (E-PET) studies were centrally reviewed, and reported using the Deauville 5-point score (DS). A total of 124 patients fulfilled the inclusion criteria. The median age was 58 years, and 88% received CHOP/CHOP-like therapy. Five years PFS and OS of the study population was 36.8% (95% CI 27.3-46.4) and 49.7% (95% CI 38.9-59.6), respectively. The presence of PET/CT-ascertained lung and/or liver involvement was associated with a worse outcome. The sensitivity of PET/CT for detecting biopsy-defined bone marrow involvement was only 18% (95% CI 4-43). An interim DS >3 was not prognostic for worse OS and PFS among CHOP/CHOP-like treated patients in uni- or multivariate analyses. A DS >3 after treatment predicted a worse prognosis. In conclusion, I-PET was not predictive of outcome in CHOP/CHOP-like treated PTCL patients when using the DS. Prospective studies are needed to determine the optimal use of PET/CT in PTCL including the role of quantitative PET/CT analysis.

Treatment-related frequency of venous thrombosis in lower esophageal, gastro-esophageal and gastric cancer--a clinical prospective study of outcome and prognostic factors.

INTRODUCTION: Prospective studies of chemotherapy-associated VTE in cancer patients undergoing neoadjuvant chemotherapy in combination with curative intended surgery have not been reported for upper gastrointestinal cancer. In this clinical prospective study, we sought to estimate the incidence of VTE in esophagogastric cancer (OEC) patients scheduled for a specific perioperative chemotherapy regime: oxaliplatin, capecitabine, and epirubicin, (EXE) and curative intended surgery. MATERIAL AND METHODS: A total of 129 consecutive OEC patients were examined using state-of-the-art bilateral compression ultrasound (biCUS) for deep vein thrombosis (DVT) before undergoing preoperative chemotherapy, surgery, and postoperative chemotherapy. In addition 79 were also consecutively scanned at baseline for pulmonary embolism (PE) using state-of-the-art computer tomography pulmonary angiography (CTPA). RESULTS: There were 21 VTE cases throughout the course of treatment (16%, 95% confidence interval [95% CI]: 10 - 24%) among the patients examined using both biCUS and CTPA. Fourteen of 21 VTE was incidental (68%, 95% CI: 43 -85) and 7 VTE events was symptomatic (33%, 15 - 57). The median overall survival was 18months (95% CI: 13 - 24) in patients without any VTE and 14months (95% CI: 7 -30, P = 0.820) in patients with VTE. The cancer stage (adjusted odds ratio [OR]: 5.2, 95% CI: 1 - 21, p=0.002) and gastric cancer (OR 6.4, 95% CI: 2 - 21, P = 0.002) was a significant predictor of VTE. CONCLUSION: The incidence of VTE in patients undergoing EXE neoadjuvant chemotherapy was high, particularly among patients with initial stage III and IV cancers. In addition, a substantial number of chemotherapy-related VTE cases were asymptomatic.

(18)F-fluorodeoxyglucose-positron emission tomography/computed tomography after one cycle of chemotherapy in patients with diffuse large B-cell lymphoma: results of a Nordic/US intergroup study.

We evaluated the predictive value of interim positon emission tomography (I-PET) after one course of chemoimmunotherapy in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). One hundred and twelve patients with DLBCL were enrolled. All patients had PET/computed tomography (CT) scans performed after one course of chemotherapy (PET-1). I-PET scans were categorized according to International Harmonization Project criteria (IHP), Deauville 5-point scale (D 5PS) with scores 1-3 considered negative (D 5PS > 3) and D 5PS with scores 1-4 considered negative (D 5PS = 5). Ratios of tumor maximum standardized uptake value (SUVmax) to liver SUVmax were also analyzed. We found no difference in progression-free survival (PFS) between PET-negative and PET-positive patients according to IHP and D 5PS > 3. The 2-year PFS using D 5PS = 5 was 50.9% in the PET-positive group and 84.8% in the PET-negative group (p = 0.002). A tumor/liver SUVmax cut-off of 3.1 to distinguish D 5PS scores of 4 and 5 provided the best prognostic value. PET after one course of chemotherapy was not able to safely discriminate PET-positive and PET-negative patients in different prognostic groups.

[Recurrent periods of respiratory tract infections in a 22-year-old].

A 22-year-old male with recurrent periods of coughing and nasal discharge was unable to work and cooperate. A bronchoscopy revealed high amounts of leucocytes and no eosinofils, acute inflammation and > 105/ml Streptococcus pneumoniae susceptible to penicillin. The symptoms relapsed after penicillin and at the age of 24 the patient was CT-scanned which revealed bilateral sinusitis, mastoiditis and bronchiectasis. Treatment with azithromycin and a weight loss programme (from 156 kg) improved the health of the patient, who was an orangutan. This highlights the benefit of cooperation between medical doctors and veterinarians.

Very late relapse of PTLD 10 yr after allogeneic HSCT and nine yr after stopping immunosuppressive therapy.

We present a very late onset relapse of PTLD 10 yr after allogeneic HSCT in a patient in third remission for ALL, nine yr after the first episode of PTLD. The recipient was conditioned with fractionated TBI 12 Gy, cyclophosphamide, and horse ATG. The first episode of PTLD with a large retroperitoneal tumor occurred one yr after transplantation; a residual tumor infiltrating spleen and colon was resected one yr later. Due to continual pathological signals in liver and lungs, persistent fever, and an M-component in peripheral blood, a new course of four rituximab doses was given, after which the fever settled, the PET scan normalized, and the M-component disappeared. Without any ongoing immunosuppressive therapy, PTLD relapsed nine yr later with large intra-abdominal lymph node masses causing ureteric obstruction with bilateral hydronephrosis. Pathological features were identical to the primary PTLD tumor: EBV related, of donor origin, positive for CD138 and CD79 alpha, but negative for CD20 and CD19. The transcription factor PAX5 was negative but BOB1 and OCT2 were positive, consistent with plasmablastic lymphoma. The relapse was successfully treated with a combination of low dose chemotherapy and rituximab. Five yr after end of treatment, the girl has moderately reduced renal function but otherwise remains well without evidence of disease.

Impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography staging in newly diagnosed classical Hodgkin lymphoma: fewer cases with stage I disease and more with skeletal involvement.

(18)F-Fluorodeoxyglucose positron emission tomography/ computed tomography (PET/CT) is a highly accurate staging method in classical Hodgkin lymphoma (cHL). We retrospectively compared the staging results obtained in two large cohorts of patients with cHL diagnosed before (n = 324) and after (n = 406) the introduction of PET/CT staging in a retrospective study. In PET/CT staged patients, stage I disease was less frequent (16% vs. 27%, p < 0.001) while stage IV disease was more frequent (17% vs. 10%, p = 0.02). Imaging-detected skeletal involvement was recognized more often in PET/CT staged patients (17% vs. 2%, p < 0.001), and the presence of focal skeletal PET/CT lesions was associated with higher risk of progression (hazard ratio [HR] 1.96, 95% confidence interval [CI]: 1.14-3.36). The German Hodgkin Study Group (GHSG) risk classification (early, intermediate, advanced disease) predicted outcome in PET/CT staged patients. In conclusion, PET/CT led to higher disease stages, and the more frequently diagnosed skeletal lesions may be an adverse prognostic factor.

Mazabraud's syndrome: case report and literature review.

Mazabraud's syndrome is a rare disorder characterized by the association of single or multiple intramuscular myxomas with fibrous dysplasia. Here, we present the first case of Mazabraud's syndrome visualized on 18F-FDG PET/CT with histopathological confirmation of the myxoma. Our case demonstrates a slightly increased FDG uptake (SUVmax 2.1) within the myxomas and a moderately to highly increased tracer uptake (SUVmax 7.0) within the fibrous dysplastic lesions. The typical histological appearance of the intramuscular myxoma confirmed the radiological diagnosis. Further, we discuss the imaging findings and the histopathological features of this rare case with a review of the related literature.

Combined 18F-fluoride and 18F-FDG PET/CT scanning for evaluation of malignancy: results of an international multicenter trial.

UNLABELLED: (18)F-FDG PET/CT is used in a variety of cancers, but because of variable rates of glucose metabolism, not all cancers are reliably identified. (18)F(-) PET/CT allows for the acquisition of highly sensitive and specific images of the skeleton. We prospectively evaluated combined (18)F(-)/(18)F-FDG as a single PET/CT examination for evaluation of cancer patients and compared it with separate (18)F(-) PET/CT and (18)F-FDG PET/CT scans. METHODS: One hundred fifteen participants with cancer were prospectively enrolled in an international multicenter trial evaluating (18)F(-) PET/CT, (18)F-FDG PET/CT, and combined (18)F(-)/(18)F-FDG PET/CT. The 3 PET/CT scans were performed sequentially within 4 wk of one another for each patient. RESULTS: (18)F(-)/(18)F-FDG PET/CT allowed for accurate interpretation of radiotracer uptake outside the skeleton, with findings similar to those of (18)F-FDG PET/CT. In 19 participants, skeletal disease was more extensive on (18)F(-) PET/CT and (18)F(-)/(18)F-FDG PET/CT than on (18)F-FDG PET/CT. In another 29 participants, (18)F(-) PET/CT and (18)F(-)/(18)F-FDG PET/CT showed osseous metastases where (18)F-FDG PET/CT was negative. The extent of skeletal lesions was similar in 18 participants on all 3 scans. CONCLUSION: This trial demonstrated that combined (18)F(-)/(18)F-FDG PET/CT shows promising results when compared with separate (18)F(-) PET/CT and (18)F-FDG PET/CT for evaluation of cancer patients. This result opens the possibility for improved patient care and reduction in health-care costs, as will be further evaluated in future trials.

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.

Positron emission tomography/computed tomography surveillance in patients with Hodgkin lymphoma in first remission has a low positive predictive value and high costs.

BACKGROUND: The value of performing post-therapy routine surveillance imaging in patients with Hodgkin lymphoma is controversial. This study evaluates the utility of positron emission tomography/computed tomography using 2-[18F]fluoro-2-deoxyglucose for this purpose and in situations with suspected lymphoma relapse. DESIGN AND METHODS: We conducted a multicenter retrospective study. Patients with newly diagnosed Hodgkin lymphoma achieving at least a partial remission on first-line therapy were eligible if they received positron emission tomography/computed tomography surveillance during follow-up. Two types of imaging surveillance were analyzed: "routine" when patients showed no signs of relapse at referral to positron emission tomography/computed tomography, and "clinically indicated" when recurrence was suspected. RESULTS: A total of 211 routine and 88 clinically indicated positron emission tomography/computed tomography studies were performed in 161 patients. In ten of 22 patients with recurrence of Hodgkin lymphoma, routine imaging surveillance was the primary tool for the diagnosis of the relapse. Extranodal disease, interim positron emission tomography-positive lesions and positron emission tomography activity at response evaluation were all associated with a positron emission tomography/computed tomography-diagnosed preclinical relapse. The true positive rates of routine and clinically indicated imaging were 5% and 13%, respectively (P = 0.02). The overall positive predictive value and negative predictive value of positron emission tomography/computed tomography were 28% and 100%, respectively. The estimated cost per routine imaging diagnosed relapse was US$ 50,778. CONCLUSIONS: Negative positron emission tomography/computed tomography reliably rules out a relapse. The high false positive rate is, however, an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low positive predictive value make positron emission tomography/computed tomography unsuitable for routine surveillance of patients with Hodgkin lymphoma.