Early restaging positron emission tomography with ( 18)F-fluorodeoxyglucose predicts outcome in patients with aggressive non-Hodgkin's lymphoma.

BACKGROUND: Less than half of all patients with aggressive non-Hodgkin's lymphoma (NHL) are cured with standard chemotherapy. Therefore, it is important to distinguish between responders to standard treatment and non-responders who may benefit from an early change to a more effective therapy. This study was intended to assess the value of a midtreatment fluorine-18 fluorodeoxyglucose positron emission tomography ([(18)F]FDG-PET) scan to predict clinical outcome in patients with aggressive NHL. PATIENTS AND METHODS: Seventy newly diagnosed patients with aggressive NHL, who were treated with doxorubicin-containing chemotherapy, underwent a [(18)F]FDG-PET scan at midtreatment. Presence or absence of abnormal [(18)F]FDG uptake was related to progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier survival analysis. Multivariate analysis was performed to evaluate the effect of the International Prognostic Index (IPI) and early [(18)F]FDG-PET findings on PFS and OS. RESULTS: At midtreatment, 33 patients showed persistent abnormal [(18)F]FDG uptake and none of these patients achieved a durable complete remission (CR), whereas 37 patients showed a negative scan; 31/37 remained in CR, with a median follow-up of 1107 days. Only 6/37 patients either achieved a partial response or relapsed. Comparison between groups indicated a statistically significant association between [(18)F]FDG-PET findings and PFS (P <1 x 10(-5)) and OS (P <1 x 10(-5)). In multivariate analysis, [(18)F]FDG-PET at midtreatment was a stronger prognostic factor for PFS (P <1 x 10(-7)) and OS (P <9 x 10(-6)) than the IPI (P <0.11 and P <0.03, respectively). CONCLUSIONS: Early restaging [(18)F]FDG-PET may be used to tailor induction chemotherapy in patients with aggressive NHL.     

Positron emission tomography (PET) for staging and evaluation of response to treatment in patients with Hodgkin's disease.

Forty two examinations utilizing F-18 FDG-PET were performed in 23 patients with Hodgkin's disease to study for involved lymphoma regions and compared to conventional staging procedures. Twenty stagings were performed at diagnosis of untreated Hodgkin's disease or at first relapse, and 22 restagings during and after chemoradiotherapy. At diagnosis in 5 of 20 patients PET and other procedures revealed different extranodal manifestations and in 3 patients established different clinical staging. PET seemed to be accurate in the assessment of lymphoma involvement in nodal sites. During follow up, in 10 out of 22 investigations different results and discrepancy were recorded, mostly due to the different extent of F-18-FDG metabolism in residual masses in lymphatic tissues compared to CT, X-ray or ultrasonography. The results indicate that PET may have advantages in the assessment of remissions in nodal sites. Less conclusive results were observed with regard to extranodal involvement or inflammatory disease. In conclusion PET may be sufficient for the staging of the majority of patients with Hodgkin's disease and particularly for assessing remission status in nodal sites, but PET may have disadvantages in the evaluation of extranodal lymphoma and inflammatory disease.     

正电子发射断层扫描仪PET中的数据校正常用方法

介绍了正电子发射断层扫描（PET）中各种校正的意义及常见算法，这些校正包括归一化校正，衰变校正，散射与衰减校正，活度刻度等。对校正算法的最新进展和PET相关设备中的校正算法也做了些介绍。恰当的校正对提高PET的成象质量及定量分析的准确性非常重要。因此，校正算法是PET设备软件系统中所必不可少的组成部分。     

Early detection of relapse by whole-body positron emission tomography in the follow-up of patients with Hodgkin's disease.

BACKGROUND: Relapse after treatment of Hodgkin's disease (HD) is usually identified as a result of the investigation of symptoms. We undertook this study to examine the value of whole-body positron emission tomography (PET) for the detection of preclinical relapse. PATIENTS AND METHODS: Thirty-six patients underwent 2-[fluorine-18]fluoro-2-deoxy-D-glucose ((18)F-FDG) PET at the end of treatment and than every 4-6 months for 2-3 years after the end of polychemotherapy and/or radiotherapy. In those cases of abnormal (18)F-FDG accumulation a confirmatory study was performed 4-6 weeks later. RESULTS: One patient had residual tumor and four patients relapsed during a follow-up of 5-24 months. All five events were correctly identified early by (18)F-FDG PET. Residual tumor or relapse was never first diagnosed based on clinical examination, laboratory findings or computed tomography (CT) studies. Two patients presented B symptoms and the three others were asymptomatic at the time of residual disease or relapse. Confirmation of residual disease or relapse was obtained by biopsy in four patients 1, 1, 5 and 9 months after PET and by unequivocal clinical symptoms and CT studies in one patient 3 months after PET. False-positive (18)F-FDG PET studies incorrectly suggested possible relapse in six other patients, but the confirmatory PET was always negative. Our study also provides important information about physiological (18)F-FDG uptake in the thymus. CONCLUSIONS: Our data suggest the potential of (18)F-FDG PET to detect preclinical relapse in patients with HD. This could help identify patients requiring salvage chemotherapy at the time of minimal disease rather than at the time of clinically overt relapse. Further studies are warranted to determine the impact of PET on treatment management and outcome. In fact, the aim of follow-up procedures is not only to detect preclinical relapse but mainly to obtain better results by starting salvage treatment earlier. A cost-benefit analysis will also be necessary before (18)F-FDG PET can be used routinely in the follow-up of patients with HD.     

Predictive role of positron emission tomography (PET) in the outcome of lymphoma patients

An extensive analysis of the reliability of positron emission tomography (PET) after induction treatment in patients with Hodgkin's disease (HD) or aggressive non-Hodgkin's lymphoma (NHL). In all, 75 untreated patients with HD (n=41) or aggressive NHL (n=34) were studied with both PET and CT scans following standard chemotherapy induction therapy (ABVD or MACOP-B) with/without radiotherapy. Histopathological analysis was performed when considered necessary. After treatment, four out of five (80%) patients who were PET(+)/CT(-) relapsed, as compared with zero out of 29 patients in the PET(-)/CT(-) subset. Among the 41 CT(+) patients, 10 out of 11 (91%) who were PET(+) relapsed, as compared with 0 out of 30 who were PET(-). The actuarial relapse-free survival (RFS) rates were 9 and 100% in the PET(+) and PET(-) subsets, respectively (P=0.00001). All five patients who were PET(+)/CT(-) underwent a lymph node biopsy: in four (80%) cases, persistent lymphoma and was confirmed at histopathological examination. Two HD patients who were PET(-)/CT(+) (with large residual masses in the mediastinum or lung) were submitted to biopsy, which in both cases revealed only fibrosis. In HD and aggressive NHL patients, PET positivity after induction treatment is highly predictive for the presence of residual disease, with significant differences being observable in terms of RFS. PET negativity at restaging strongly suggests the absence of active disease; histopathological verification is important in patients who show PET positivity.     

The role of positron emission tomography (PET) in the management of lymphoma patients

Background: Treatment of both Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL) with abdominal presentation at the time of diagnosis is often followed by detection of residual masses by computed tomography (CT). However, CT is usually unable to disciminate between residual tumor and fibrosis/necrosis. We investigated the ability of fluorine-18 fluorodeoxyglucose positron emission tomography (PET) to differentiate between residual active tumor tissue and fibrosis.Patients and methods: Forty-four patients with HD or aggressive NHL presenting abdominal involvement (41% with bulky mass) were studied with CT and PET at the end of chemotherapy ± radiation therapy.Results: After treatment, seven patients had negative PET and CT, and none of them relapsed. The remaining 37 patients all had positive CT (abnormalities 10%). All of the 13 who also had positive PET relapsed (100%). By contrast, there was only 1 (4%) relapse among the 24 patients who were positive at CT but negative at PET. The two-year actuarial relapse-free survival rate was 95% for those with negative PET compared with 0% for positive PET patients (P < 0.000000).Conclusions: In lymphoma patients with abdominal masses who present CT positivity at restaging, PET should be considered the noninvasive imaging modality of choice for differentiating early recurrences or residual disease from fibrosis.     

18-fluorodeoxy-glucose positron emission computed tomography as predictive of response after chemoradiation in oesophageal cancer patients

IntroductionThe purpose of this study was to evaluate if a baseline, an interim or a post-chemoradiation (CTRT) 18-fluorodeoxy-glucose positron emission computed tomography (18F-FDG PET/CT) studies could provide information on pathologic response to CTRT and overall survival (OS).Materials and methodsThirty-one patients with histologically proven adenocarcinoma or squamous cell carcinoma of the oesophagus, fit for trimodality therapy were prospectively enrolled. Most were men (93.5%), and had a stage III cancer (74.2%). Chemotherapy consisted of oxaliplatin/5-fluorouracil (45.2%) and taxane/5-fluorouracil (54.8%). All patients underwent a baseline, an interim (performed 12 ± 2 days after the onset of CTRT) and a post-CTRT 18F-FDG PET/CT study. The 18F-FDG PET/CT variables evaluated were at baseline, interim and post-CTRT studies maximum standardised uptake value (SUVmax) and total lesion glycolysis (TLG). Clinical and 18F-FDG PET/CT parameters were correlated with pathologic complete response (pathCR) and OS.ResultsAmong the 31 patients studied, 61.3% achieved a clinical complete response (cCR) and 87.1% had surgery. The median OS was 35.1 months (95% confidence interval (CI): 19.9–NA). PathCR rate was 22.2%. There was only a marginal association between cCR and pathCR (p = 0.06). None of the other variables was predictive of pathCR. There was association between OS and baseline TLG (p = 0.03) at the optimal cutoff TLG value of 75.15. Additionally, TLG and ΔTLG post-CTRT were also associated with OS (p = 0.01 and 0.03, respectively).ConclusionNone of the PET parameters is predictive of pathCR but TLG at baseline and post-CTRT are prognostic of OS.     

18F-FDG whole body positron emission tomography (PET) in patients with unknown primary tumours (UPT)

The management of patients with unknown primary tumours (UPT) often includes a large number of radiographical studies and invasive procedures, but the occult primary tumour is detected in less than 25%. In this prospective study we explored whether non-invasive whole body PET scans using FDG (18-F-fluorodeoxyglucose) are of clinical value in detection of UPT. Whole-body FDG-PET scans were performed in 20 patients following standard staging procedures according to histology. PET results were verified either histologically or by the clinical course of the disease. 11 patients had neck metastases (5 squamous cell, 5 adenocarcinomas and 1 poorly differentiated carcinoma). The remaining patients had metastases located in bone (3), bone marrow (1), brain (1), pericardium (1), skin (1), pleura (1) and chest wall (1). All metastatic lesions were visible with PET. In 13 patients PET suggested the site for the primary tumour and this was verified in 9 (45%), either histologically or by the clinical course of disease. 8 of these had primary lung cancer and 1 had carcinoma at the basis of the tongue. In most patients PET had no treatment related implications. 3 patients with non-small cell lung cancer (NSCLC) received chemotherapy prompted by the PET result. The rest received either radical radiotherapy to the head and neck region (7), palliative radiotherapy to the metastatic lesion (8), chemotherapy based on signet ring cell carcinoma in bone marrow (1) or no therapy (1). These results indicates that PET is useful in UPT preceding expensive and invasive diagnostic procedures and can result in a faster diagnosis in approximately one third of the patients who then avoid unnecessary extensive procedures. Furthermore, a larger proportion of patients will receive treatment aimed at the correct diagnosis. A prospective cost-effectiveness analysis of PET in this setting is warranted     

NCCN task force report: positron emission tomography (PET)/computed tomography (CT) scanning in cancer

The use of positron emission tomography (PET) is increasing rapidly in the United States, with the most common use of PET scanning related to oncology. It is especially useful in the staging and management of lymphoma, lung cancer, and colorectal cancer, according to a panel of expert radiologists, surgeons, radiation oncologists, nuclear medicine physicians, medical oncologists, and general internists convened in November 2006 by the National Comprehensive Cancer Network. The Task Force was charged with reviewing existing data and developing clinical recommendations for the use of PET scans in the evaluation and management of breast cancer, colon cancer, non-small cell lung cancer, and lymphoma. This report summarizes the proceedings of this meeting, including discussions of the background of PET, possible future developments, and the role of PET in oncology.     

Imaging of biological character of cancer using positron emission tomography(PET)

There are two types of radiopharmaceuticals for cancer imaging with PET. The first target is a marker of cancer proliferation, and positron-labeled analogs of glucose, amino acid, and nucleic acid are commonly used for this purpose. 18F-FDG is a typical tracer of this approach. The second target is visualization of cancer-specific biological characters. In Tohoku University, we developed 18F-fluorodeoxygalactose(18F-FDGal), 18F-SAV03M, and 18F-FRP170 as tracers of the second category. 18F-FDGal is metabolized and trapped in the tissue by liver-specific galactose metabolic enzymes. It is used for detecting well-differentiated hepatocellular carcinoma which originated from liver cells and still maintains the enzymes. 18F-SAV03M is a substrate for matrix metalloproteinase-2 and was developed for the visualization of tumor invasiveness. 18F-FRP170 was developed for the visualization of hypoxic cancer cells which cause radiotherapy and chemotherapy resistance. In addition, the uses of labeled antisense oligonucleotide and aptamers were introduced for the visualization of specific mRNA and proteins expression.     

The role of Fluorine-18-Fluorodeoxyglucose positron emission tomography in staging and restaging of patients with osteosarcoma

Background

The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with Fluorine-18-Fluorodeoxyglucose (FDG) in patients with osteosarcoma (OS).

Methods

A comprehensive literature search of published studies through October 10^th, 2012 in PubMed/MEDLINE, Embase and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed.

Results

We identified 13 studies including 289 patients with OS. With regard to the staging and restaging of OS, the diagnostic performance of FDG-PET and PET/CT seem to be high; FDG-PET and PET/CT seem to be superior to bone scintigraphy and conventional imaging methods in detecting bone metastases; conversely, spiral CT seems to be superior to FDG-PET in detecting pulmonary metastases from OS

Conclusions

Metabolic imaging may provide additional information in the evaluation of OS patients. The combination of FDG-PET or FDG-PET/CT with conventional imaging methods seems to be a valuable tool in the staging and restaging of OS and may have a relevant impact on the treatment planning.     

Early restaging positron emission tomography with 18F-fluorodeoxyglucose in aggressive non-Hodgkin's lymphomas: is it too easy to be true?

In the September 2002 issue of Annals of Oncology, Spaepen and coworkers [1] reported the prognostic value of earlyrestaging positron emission tomography with fluorine-18 fluorodeoxyglucose[(¹⁸F) FDG –PET] in 70 consecutive patients with aggressivenon-Hodgkin’s lymphoma     

Single photon emission tomography/computed tomography (SPET/CT) and positron emission tomography/computed tomography (PET/CT) to image cancer

Hybrid systems associating the sharpness of anatomic images coming from computed tomography (CT) and radionuclide functional imaging (SPET or PET) are opening a new era in oncology. This multimodal imaging method is now routinely used for the diagnosis, extent, follow up, treatment response and detection of occult disease in different types of malignancies with a significant impact on the treatment strategy leading for a change for more than 68% of all investigated patients.     

Localised disease in cancer of unknown primary (CUP): The value of positron emission tomography (PET) for individual therapeutic management

Background:Two to four percent of cancer patients presentwith CUP syndrome. Median survival for localised disease is 20 and fordisseminated disease, seven months. For localised disease, curativetreatment is more likely and individual therapeutic strategies becomemore important. After conservative diagnostic procedures including MRI,the primary is detected in less than 25%. The diagnostic value ofPET and its influence on therapeutic strategies was evaluated. Patients and methods:Forty-two patients with localised CUPwere investigated from 5 of 98 to 10 of 2000. The presenting site waslymph node metastasis in 34 and visceral metastasis in 8 patients. Aftera median of 7 (3–11) diagnostic procedures without detection ofthe primary, but evidence of localised disease, PET was performed withfluorine-18-fluorodeoxyglucose. Results:In 26 of 42patients (62%), a primary was suggested by PET and confirmed in18 (43%). In 5 of 18 patients beyond localised disease,additional dissemination, not detected by previous diagnostic measures,was diagnosed by PET. Overall, dissemination was only detected only byPET in 16 of 42 patients (38%). In 29 of 42 patients(69%), the PET result influenced selection of the definitivetreatment. Conclusion:In CUP patients, PET has acertain impact on detection of the primary as well as of thedisseminated disease, and may also have a certain impact on therapeuticmanagement.     

Prognostic predictive value of 18F-fluorodeoxyglucose positron emission tomography for patients with pancreatic cancer.

18Fluorine-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is a unique imaging diagnostic tool to evaluate glucose metabolism and hexokinase activity which may reflect the aggressiveness of a tumor. Thirty-seven patients with primary pancreatic cancer were evaluated with 18F-FDG-PET. Thirteen patients underwent resection for the pancreatic cancer and 24 patients had unresectable tumors. The standardized uptake values (SUV) of 18F-FDG in the primary tumors were calculated. No correlations were found between the SUV in the tumors and the metastatic status to the peritoneal/liver, TNM factors/stage, or resectability. The patients were divided into 2 groups with high and low SUV, with the cut-off value being 3.0 (median SUV value of 37 cases). No differences in the probability of survival were observed between the 2 groups in the patients with resectable tumors. However, in the patients with unresectable tumors, those in the high SUV group had a significantly shorter prognosis than those in the low SUV group. Moreover, a multivariate analysis of survival indicated that SUV is an independent prognostic factor for patients with unresectable pancreatic cancer.     

Advantages of positron emission tomography (PET) with respect to computed tomography in the follow-up of lymphoma patients with abdominal presentation

For abdominal lymphoma patients, fluorine-18 fluorodeoxyglucose positron emission tomography (PET) provides unique information on the presence of residual active disease. We provide an update on the largest reported cohort of patients whose management following induction therapy was based on routine PET and computed tomography (CT) restaging. Fifty-nine patients with Hodgkin's disease or aggressive non-Hodgkin's lymphoma presenting abdominal involvement (35% with bulky disease) were studied with both PET and CT following combined chemotherapy/radiation treatment. After treatment, 3/3 (100%) patients who were PET+/CT- relapsed, compared with 0/7 patients in the PET-/CT- subset. Among the 49 patients who were CT+, six of the 10 (60%) who were PET+ relapsed, as compared with only two of the 39 (5%) who were PET-. The actuarial relapse-free survival (RFS) rates were 0 and 100% in the PET+/CT- and PET-/CT- subsets, respectively. In the PET+/CT+ subset, RFS was 94% at 5 years. PET restaging is very valuable for the identification of patients who would need appropriate second-line therapy because of the presence of residual active abdominal disease and should be made widely available in combination with CT.     

Positron emission tomography in patients with Hodgkin's disease: correlation to histopathologic subtypes

The aim of this study was to evaluate the initial staging and restaging of Hodgkin's disease (HD) according to histopathologic subtype (HST) using fluorine-18-deoxyglucose-positron emission tomography (PET). Special attention was paid to the accuracy of PET for detection of bone marrow infiltration (BMI). 44 patients with HD (m:f = 28:16, mean age 36 +/- 15 years) underwent PET; 16 were primary stagings and 28 restaging examinations. PET results were compared with methods of conventional staging including computed tomography (CT) and bone marrow biopsy. Viable tumor tissue was detected by PET in 25/44 cases, 16 nodular sclerosis (NS), 4 mixed cellularity (MC), 3 lymphocyte predominance (LP) and 2 cases with a nonclassified subtype (NC). FDG tumor uptake, measured as standard uptake value (SUV), ranged from 1.7 to 13. Maximum SUV in NS was 5.2 +/- 1.5 (2.5-7.3), 3.2 +/- 2.4 for MC, 2.6 +/- 0.7 for LP, and 9.1 +/- 3.8 for NC, respectively. In 7% of all patients (3/44) bone marrow infiltrations were detected by PET. PET is known for its superior detection of viable tissue in HD. In this study it was shown that HST does not influence the intensity of glucose metabolism, although 2 patients with NC showed the highest SUVs. In addition PET accurately detected focal BMI and may thus be applied before BMB to guide its optimal use.