Prognostic significance of novel F-FDG PET/CT defined tumour variables in patients with oesophageal cancer

Purpose

¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) combined with computed tomography (PET/CT) is now established as a routine staging investigation of oesophageal cancer (OC). The aim of the study was to determine the prognostic significance of PET/CT defined tumour variables including maximum standardised uptake value (SUVmax), tumour length (TL), metastatic length of disease (MLoD), metabolic tumour volume (MTV), total lesion glycolysis (TLG) and total local nodal metastasis count (PET/CT LNMC).

Materials and methods

103 pre-treatment OC patients (76 adenocarcinoma, 25 squamous cell carcinoma, 1 poorly differentiated and 1 neuroendocrine tumour) were staged using PET/CT. The prognostic value of the measured tumour variables were tested using log-rank analysis of the Kaplan–Meier method and Cox's proportional hazards method. Primary outcome measure was survival from diagnosis.

Results

Univariate analysis showed all variables to have strong statistical significance in relation to survival. Multivariate analysis demonstrated three variables that were significantly and independently associated with survival; MLoD (HR 1.035, 95% CI 1.008–1.064, p = 0.011), TLG (HR 1.002, 95% CI 1.000–1.003, p = 0.018) and PET/CT LNMC (HR 0.048–0.633, 95% CI 0.005–2.725, p = 0.015).

Conclusion

MLoD, TLG, and PET/CT LNMC are important prognostic indicators in OC. This is the first study to demonstrate an independent statistical association between TLG, MLoD and survival by multivariable analysis, and highlights the value of staging OC patients with PET/CT using functional tumour variables.     

Extended staging of oesophageal cancer using FDG-PET - a critical appraisal

Background and aim

Oesophageal cancer (OC) is a highly aggressive tumour with unfavorable prognosis due to early stages metastases. Treatment and survival rates are highly correlated with tumour wall invasion, lymphatic involvement and metastatic spread. Thus, an accurate staging at initial diagnosis is fundamental for optimal management. In the present review article the potential role of the FDG-PET in the staging of OC is discussed.

Methods

A systematic review of all papers published in PubMed until June 2010 was performed.

Results

Endoscopic ultrasound (EUS) is helpful for T and N staging but not for M staging. CT plays a complementary role to EUS in T staging, especially in excluding T4 disease. However, in N staging, CT relies on “size criteria” (<1cm = benign, >1cm = malignant) which reduces its sensitivity and specificity.FDG-PET has been demonstrated to be a very helpful tool in staging and re-staging OC. Most OCs demonstrate high FDG accumulation and are usually well detected with PET. Unfortunately, PET cannot reveal very small lesions due to its limited spatial resolution, therefore limiting the usefulness of PET in T staging. In N staging, an FDG positive node is highly likely to contain disease. However, FDG-PET cannot reliably separate the primary site from closely adjacent nodes.The real and unquestionable additional diagnostic value of FDG-PET in comparison to CT and EUS is in evaluating distant metastases.

Conclusions

It appears reasonable to include FDG PET/CT in the diagnostic algorithm of patients with OC in order to better define the optimal therapeutic approach.     

Integrated PET/CT in the preoperative staging of lung cancer: A prospective comparison of CT,PET and integrated PET/CT

Purpose

The purpose of this study was to evaluate the role of integrated PET/CT in the staging of lung cancer compared with CT alone or PET alone.

Materials and methods

Thirty-three patients underwent integrated PET/CT for the staging of lung cancer. The tumor, node and metastasis (TNM) stages were assessed with CT, PET and integrated PET–CT and compared with the surgical and pathological staging.

Results

CT correctly evaluated the (T) status in (64%) of the patients, PET in (59%) and PET/CT in (86%). CT correctly evaluated the (N) status in (73%) of the patients, PET in (76%), and PET/CT (88%) with accuracy, sensitivity, specificity, PPV and NPV were 73%, 78%, 71%, 50% and 94% for CT, 76%, 67%, 79%, 55% and 95% for PET and 88%, 89%, 88%, 73% and 100% for PET/CT respectively, and for (M) status were 91%, 86%, 92%, 75% and 96% for CT, 88%, 71%, 92%, 71% and 92% for PET and 97%, 100%, 96%, 88% and 100% for PET/CT respectively. Regarding the overall TNM staging CT correctly staged 24 patients. PET correctly staged 23 cases while PET/CT correctly staged 30 cases. A significant difference in the accuracy of overall tumor staging between PET/CT and CT (P = 0.0412) or PET (P = 0.0233).

Conclusion

The integrated PET/CT is superior to either CT or PET in the staging of lung cancer which has an important impact on selection of the appropriate treatment regimen.     

The clinical utility of FDG-PET/CT in follow up and restaging of breast cancer patients

Background

Early diagnosis and accurate staging of loco-regional and distant recurrence after treatment of breast cancer is decisive for further therapeutic planning. Our aim was to evaluate the role of FDG-PET/CT in the follow up and restaging of breast cancer patients.

Methods

We retrospectively evaluated 34 female patients with a history of breast cancer. Patients were referred for a PET/CT scan because of suspected recurrence (n = 15), whole body staging in already confirmed cases of recurrence (n = 5), follow up and reassurance in asymptomatic patients (n = 7), follow up after local ablative therapy of liver metastases (n = 5), follow up after treatment of bone metastases (n = 2). PET-CT findings were compared with the findings obtained by other imaging modalities, histopathology, together with clinical and imaging follow up for at least 6 months.

Results

The PET/CT was considered pathological in 21/34 patients. Incorrect interpretations of PET/CT images occurred in 3 patients (8.8%). PET/CT showed an overall diagnostic accuracy of 91.2% with a sensitivity of 90.5% and a specificity of 92.3%. The PPV and NPV were 95% and 85.7%, respectively.

Conclusion

FDG-PET/CT may play a substantial role in the restaging and follow up of patients with breast cancer showing high sensitivity and specificity.     

Clinical value of FDG PET or PET/CT in urinary bladder cancer: a systemic review and meta-analysis

Aim

The purpose of the current study was to conduct a systemic review and meta-analysis of the published literature to evaluate the diagnostic accuracy of FDG PET or PET/CT in urinary bladder cancer.

Materials and methods

The authors conducted a systematic MEDLINE search of articles published between January 2000 and December 2010. Two reviewers independently assessed the methodological quality of each study. We conducted a meta-analysis of pooled sensitivity and specificity in detecting primary and metastatic lesions of bladder cancer.

Results

Six studies met the inclusion criteria. The pooled sensitivity and specificity of PET/CT for primary lesion detection of bladder cancer were 0.90 (95% CI: 0.70–0.99) and 1.00 (95% CI: 0.74–1.00), respectively. The pooled sensitivity and specificity of FDG PET or PET/CT for staging or restaging (metastatic lesions) of bladder cancer were 0.82 (95% CI: 0.72–0.89) and 0.89 (95% CI: 0.81–0.95), respectively.

Conclusion

The diagnostic accuracy of FDG PET or PET/CT is good in metastatic lesions of urinary bladder cancer. Due to the small number of patients and limited number of studies analyzed, the diagnostic capability of FDG PET or PET/CT in detection of primary bladder wall lesions could not be assessed.     

PET/CT in initial staging and therapy response assessment of early mediastinal lymphoma

Objective

To detect accuracy of PET/CT in the initial staging, response after the first line and end of treatment in early mediastinal lymphoma patients compared to contrast CT.

Materials and methods

We studied 50 patients with pathologically proven lymphoma with a mean age = 27.5. All patients were at early stage. All patients performed CT and PET/CT for initial staging, after the first course of chemotherapy (after 4–6 weeks) and at the end of treatment (after 2–4 months).

Results

PET/CT upstaged 5 cases. At first line of treatment, PET/CT and CECT were agreeable in 32% of cases. PET/CT showed 100% sensitivity, 96.7% specificity, 95% positive predictive value and 100% negative predictive value. At the end of treatment both methods showed a 46% agreement. PET/CT was statistically significant in the follow up of hilar and axillary lymph nodes. PET/CT showed 100% sensitivity and specificity; compared to 62.5% sensitivity and 97.6% specificity for CECT in detection of extra-nodal disease sites.

Conclusion

PET/CT proved higher sensitivity and specificity over CECT. The major strength of PET/CT over CECT was its higher ability for detection of extra-nodal sites of lymphoma and excluding active disease in residual nodal mass lesions on follow up.     

18F-FDG PET, combined FDG-PET/CT and MRI for evaluation of bone marrow infiltration in staging of lymphoma: a systematic review and meta-analysis

Background and purpose

Evaluation of bone marrow infiltration is an essential step in the staging of lymphoma. The accuracy of ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG PET), combined ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) and magnetic resonance imaging (MRI) in diagnosing bone marrow involvement of lymphoma has never been systematically assessed, and the present systematic review was aimed at this issue.

Methods

MEDLINE, EMBASE, Cochrane library and some other databases, from January 1995 to July 2010, were searched for initial studies. All the studies published in English or Chinese relating to the diagnostic value of ¹⁸F-FDG PET, PET/CT and MRI for patients with bone marrow involvement of lymphoma were collected. We extracted data to calculate sensitivity, specificity, SROC curves and AUC and to test for heterogeneity. The statistic software called “Meta-Disc 1.4” was used for data analysis.

Result

In 32 included studies, PET/CT had the highest pooled sensitivity, 91.6% (95%CI: 85.1, 95.9) and highest pooled specificity, 90.3% (95%CI: 85.9, 93.7). PET/CT also had the highest pooled DOR, 68.89 (95%CI: 15.88, 298.92). The AUC of PET, PET/CT, and MRI were 0.9430, 0.9505 and 0.8764. There was heterogeneity among studies and no evidence of publication bias.

Conclusion

PET/CT was a highly sensitive and specific modality in diagnosing patients with bone marrow involvement in lymphoma. Compared with MRI and PET alone, PET/CT can play important roles in the staging of lymphoma.     

Whole-body magnetic resonance imaging and FDG-PET/CT for lymphoma staging: Assessment of patient experience

Purpose

To compare patient experience of whole-body MRI and FDG-PET/CT performed for lymphoma staging.

Potential impact of PET/CT on the initial staging of lymphoma

Purpose

The aim of this study was to investigate the potential impact of PET/CT on the initial staging of lymphoma with comparison to each of the PET and CT components alone.

Materials and methods

PET/CTs from 37 patients with lymphoma undergoing initial staging were studied. Review of PET, CT and PET/CT images were done and staging of each patient by each modality was assigned and compared together. Clinical follow-up, additional imaging and histology served as the standard of reference.

Results

PET/CT correctly diagnosed 83 nodal regions as positive for lymphomatous involvement versus 61 and 57 detected by PET and CT respectively. The respective sensitivities, specificities, and accuracies for the detection of nodal involvement were: PET: 88.4%, 65%, 94%, CT 89.1%, 60.1%, 96.1%, PET/CT 96.3%, 88.3%, 98.2%. PET/CT also correctly identified more extra-nodal lesions (n = 24) than CT (n = 16) and PET (n = 15). Correct staging was more accurate at PET/CT (n = 31) in comparison to PET alone (n = 23) and CT alone (n = 21).

Conclusions

PET/CT was superior to PET and CT in the initial staging of lymphoma with significant better performance compared to PET and CT to clarify nodal and extra-nodal involved sites. The application of PET/CT rather than CT or PET is likely to be more beneficial.     

Integrated FDG-PET/CT vs. standard radiological examinations: Comparison of capability for assessment of postoperative recurrence in non-small cell lung cancer patients

Purpose

The purpose of this study was to prospectively and directly compare diagnostic capabilities of whole-body integrated FDG-PET/CT and standard radiologic examination for assessment of recurrence in postoperative non-small cell lung cancer (NSCLC) patients.

Materials and methods

A total of 92 consecutive pathologically diagnosed NSCLC patients (65 males, 27 females; mean age, 71 years) underwent pathologically and surgically proven complete resection, followed by prospective whole-body FDG-PET/CT and standard radiological examinations. Final diagnosis of recurrence was based on the results of more than 1 year of follow-up and/or pathological examinations. On both methods, the probability of recurrence was assessed in each patient by using a five-point visual scoring system, and the each final diagnosis was made by consensus between two readers. Kappa analyses were performed to determine inter-observer agreement for both methods, and ROC analyses were used to compare capability of the two methods for assessment of postoperative recurrence on a per-patient basis. Sensitivity, specificity and accuracy were also compared between PET/CT and standard radiological examination by means of McNemar's test.

Results

All inter-observer agreements were almost perfect (integrated PET/CT: κ = 0.89; standard radiological examination: κ = 0.81). There were no statistically significant differences in area under the curve, sensitivity, specificity and accuracy between integrated FDG-PET/CT and standard radiologic examinations (p > 0.05).

Conclusion

Integrated FDG-PET/CT can be used for assessment of postoperative recurrence in NSCLC patients with accuracy as good as that of standard radiological examinations.     

Comparison of whole-body PET/CT and PET/MRI in breast cancer patients: Lesion detection and quantitation of 18F-deoxyglucose uptake in lesions and in normal organ tissues

Purpose

To compare the performance of PET/MRI imaging using MR attenuation correction (MRAC) (DIXON-based 4-segment -map) in breast cancer patients with that of PET/CT using CT-based attenuation correction and to compare the quantification accuracy in lesions and in normal organ tissues.

Methods

A total of 36 patients underwent a whole-body PET/CT scan 1 h after injection and an average of 62 min later a second scan using a hybrid PET/MRI system. PET/MRI and PET/CT were compared visually by rating anatomic allocation and image contrast. Regional tracer uptake in lesions was quantified using volumes of interest, and maximal and mean standardized uptake values (SUVmax and SUVmean, respectively) were calculated. Metabolic tumor volume (MTV) of each lesion was computed on PET/MRI and PET/CT. Tracer uptake in normal organ tissue was assessed as SUVmax and SUVmean in liver, spleen, left ventricular myocardium, lung, and muscle.

Results

Overall 74 FDG positive lesions were visualized by both PET/CT and PET/MRI. No significant differences in anatomic allocation scores were found between PET/CT and PERT/MRI, while contrast score of lesions on PET/MRI was significantly higher. Both SUVmax and SUVmean of lesions were significantly higher on PET/MRI than on PET/CT, with strong correlations between PET/MRI and PET/CT data (ρ = 0.71–0.88). MTVs of all lesions were 4% lower on PET/MRI than on PET/CT, but no statistically significant difference was observed, and an excellent correlation between measurements of MTV with PET/MRI and PET/CT was found (ρ = 0.95–0.97; p < 0.0001). Both SUVmax and SUVmean were significantly lower by PET/MRI than by PET/CT for lung, liver and muscle, no significant difference was observed for spleen, while either SUVmax and SUVmean of myocardium were significantly higher by PET/MRI. High correlations were found between PET/MRI and PET/CT for both SUVmax and SUVmean of the left ventricular myocardium (ρ = 0.91; p < 0.0001), while moderate correlations were found for the other normal organ tissues (ρ = 0.36–0.61; p < 0.05).

Conclusions

PET/MRI showed equivalent performance in terms of qualitative lesion detection to PET/CT. Despite significant differences in tracer uptake quantification, due to either methodological and biological factors, PET/MRI and PET/CT measurements in lesions and normal organ tissues correlated well. This study demonstrates that integrated whole-body PET/MRI is feasible in a clinical setting with high quality and in a short examination time.     

Staging accuracy of pancreatic cancer: Comparison between non-contrast-enhanced and contrast-enhanced PET/CT

Purpose

Our aim was to clarify the diagnostic impact of contrast-enhanced (CE) ¹⁸F-fluorodeoxyglucose (FDG)–positron emission tomography (PET)/computed tomography (CT) for staging of pancreatic cancer compared to non-CE PET/CT.

Method and materials

Between April 2006 and November 2009, a total of 95 patients (age range, 36–83 years [mean age, 67]) with primary pancreatic cancer underwent ¹⁸F-FDG PET/CT examinations. Diagnostic accuracy was compared between non-CE PET/CT and CE PET/CT. Images were analyzed visually and quantitatively by two blinded reviewers. Reference standard was histological examination in 48 patients (51%) and/or confirmation of an obvious progression in number and/or size of the lesions on follow-up CT examinations in 47 patients (49%).

Results

For T-staging, invasion of duodenum (n = 20, 21%), mesentery (n = 12, 13%), and retroperitoneum (n = 13, 14%) was correctly diagnosed by both modalities. The ROC analyses revealed that the Az values of celiac artery (CA), common hepatic artery (CHA), splenic artery (SV), and superior mesenteric vein (SMV) invasion were significantly higher in the CE PET/CT group for both readers. Nodal metastasis was correctly diagnosed by CE PET/CT in 38 patients (88%) and by non-CE PET/CT in 45 patients (87%). Diagnostic accuracies of nodal metastasis in two modalities were similar. Using CE PET/CT, distant metastasis, scalene node metastasis, and peritoneal dissemination were correctly assigned in 39 patients (91%), while interpretation based on non-CE PET/CT revealed distant metastasis, scalene node metastasis, and peritoneal dissemination in 42 patients (81%). Diagnostic accuracy of distant metastasis, scalene node metastasis, and peritoneal dissemination with CE PET/CT was significantly higher than that of non-CE PET/CT (p < 0.05).

Conclusion

CE PET/CT allows a more precise assessment of distant metastasis, scalene node metastasis, and peritoneal dissemination in patients with pancreatic cancer.     

Diffusion-weighted imaging as part of hybrid PET/MRI protocols for whole-body cancer staging: Does it benefit lesion detection?

Purpose

Positron emission tomography/magnetic resonance imaging (PET/MRI) requires efficient scan protocols for whole-body cancer staging. The aim of this study was to evaluate if the application of diffusion-weighted MR imaging (DWI) results in a diagnostic benefit for lesion detection in oncologic patients if added to a whole-body [18F]-fluorodesoxyglucose ([18F]-FDG) PET/MRI protocol.

Methods

25 consecutive oncologic patients (16 men, 9 women; age 57 ± 12 years) prospectively underwent whole-body [18F]-FDG-PET/MRI including DWI on a hybrid PET/MRI scanner. A team of two readers assessed [18F]-FDG PET/MRI without DWI for primary tumors and metastases. In a second session, now considering DWI, readers reassessed [18F]-FDG PET/MRI accordingly. Additionally, the lesion-to-background contrast on [18F]-FDG PET and DWI was rated qualitatively (0, invisible; 1, low; 2, intermediate; 3, high). Wilcoxon's signed-rank test was performed to test for differences in the lesion-to-background contrast.

Results

49 lesions were detected in 16 patients (5 primaries, 44 metastases). All 49 lesions were concordantly detected by [18F]-FDG PET/MRI alone and [18F]-FDG PET/MRI with DWI. The lesion-to-background contrast on DWI compared to [18F]-FDG PET was rated lower in 22 (44.9%) of 49 detected lesions resulting in a significantly higher lesion-to-background contrast on [18F]-FDG PET compared to DWI (P = 0.001).

Conclusions

DWI as part of whole-body [18F]-FDG PET/MRI does not benefit lesion detection. Given the necessity to optimize imaging protocols with regard to patient comfort and efficacy, DWI has to be questioned as a standard tool for whole-body staging in oncologic PET/MRI.     

Role of FDG-PET and PET/CT in the diagnosis and management of vasculitis

Purpose

to investigate the role of FDG-PET and PET/CT in the evaluation of vasculitis.

Materials and methods

a systematic revision of the papers published in PubMed/Medline until December 2009 was done.

Results

FDG-PET and PET/CT have been proven to be valuable in the diagnosis of large-vessel vasculitis, especially giant cells arteritis with sensitivity values ranging 77% to 92%, and specificity values ranging 89% to 100%. In particular, FDG-PET/CT has demonstrated the potential to non-invasively diagnose the onset of the vasculitis earlier than traditional anatomical imaging techniques, thus enabling prompt treatment. False positive results mainly occur in the differential diagnosis between vasculitis and atherosclerotic vessels in elderly patients. Another area where FDG-PET/CT is gaining wider acceptance is in monitoring response to therapy; it can reliably detect the earliest changes of disease improvement post-therapy, and persistent activity is an indicator of non-responders to therapy. A few data have been reported about medium/small vessel vasculitis.

Discussion

FDG-PET and PET/CT have proven utility: (a) in the initial diagnosis of patients suspected of having vasculitis particularly in those who present with non-specific symptoms; (b) in the identification of areas of increased FDG uptake in which a biopsy should be done for obtaining a diagnosis; (c) in evaluating the extent of the disease; (d) in assessing response to treatment.     

Diagnostic value of whole-body diffusion-weighted magnetic resonance imaging for detection of primary and metastatic malignancies: A meta-analysis

Purpose

To perform a meta-analysis to evaluate the diagnostic performance of whole-body diffusion-weighted magnetic resonance imaging (WB-DWI) technique in detection of primary and metastatic malignancies compared with that of whole-body positron emission tomography/computed tomography (WB-PET/CT).

Materials and methods

Search Pubmed, MEDLINE, EMBASE and Cochrane Library database from January 1984 to July 2013 for studies comparing WB-DWI with WB-PET/CT for detection of primary and metastatic malignancies. Methodological quality was assessed by the quality assessment of diagnostic studies (QUADAS) instrument. Sensitivities, specificities, predictive values, diagnostic odds ratio (DOR) and areas under the summary receiver operator characteristic curve (AUC) were calculated. Potential threshold effect, heterogeneity and publication bias were investigated.

Result

Thirteen eligible studies were included, with a total of 1067 patients. There was no significant threshold effect. WB-DWI had a similar AUC (0.966 (95% CI, 0.940–0.992) versus 0.984 (95% CI, 0.965–0.999)) with WB-PET/CT. No significant difference was detected between AUC of WB-DWI and WB-PET/CT. WB-DWI had a pooled sensitivity of 0.897 (95% CI, 0.876–0.916) and a pooled specificity of 0.954 (95% CI, 0.944–0.962). WB-PET/CT had a pooled sensitivity of 0.895 (95% CI, 0.865–0.920) and a pooled specificity of 0.975 (95% CI, 0.966–0.981). Heterogeneity was found to stem primarily from data type (per lesion versus per patient), MR sequence (DWIBS only and DWIBS with other sequence), and primary lesion type (single type and multiple type). The Deeks's funnel plots suggested the absence of publication bias.

Conclusion

WB-DWI has similar, good diagnostic performance for the detection of primary and metastatic malignancies compared with WB-PET/CT. DWIBS with other MR sequences could further improve the diagnostic performance. More high-quality studies regarding comparison of WB-DWI and WB-PET/CT and combination of them in detecting malignancies are still needed to be conducted.     

Follow up in chest tumors: Value of integrated PET/CT

Objective

To identify the value of integrated PET/CT in the follow up of chest tumors.

Patients and methods

Whole body PET/CT studies were performed on 29 patients of variable primary and secondary chest tumors.

Results

Our findings indicate that FDG PET/CT has an important impact on evaluation and follow up of chest tumors, as it delineated the metabolic activity of the disease in 21 patients (72.41%), outlined the metabolic activity of the tumoral residue in 4 patients postoperatively (13.79%), delineated the metabolic activity of the disease in 2 patients preparing for BMT (6.89%), it differentiated between tumoral residue and post irradiation pneumonitis in 1 patient (3.44%), while it was used for the initial assessment of the metabolic activity of the disease before determining line of treatment in one patient and subsequent follow up.

Conclusion

Integrated PET/CT imaging, which combines both functional and morphologic imaging in a single examination, has shown how the initial staging and subsequent follow-up of patients with chest tumors can supersede the traditional methods of evaluation in terms of diagnostic accuracy and has an impact on the management. Limitations we encountered were subcentimetric pulmonary nodules, below 7–8 mm (beyond PET resolution) which can be overcome by short follow up.     

Performance of integrated FDG-PET/contrast-enhanced CT in the staging and restaging of colorectal cancer: Comparison with PET and enhanced CT

Objective

The purpose of this study was to assess the diagnostic value of PET/CT as a one step examination in patients with colorectal cancer. Therefore we proved whether diagnostic PET/CT adds information over PET or contrast-enhanced CT alone for staging or restaging of patients with colorectal cancer.

Methods

Seventy-three patients (46 males and 27 females; age range: 50-81 years; mean age: 67 years) with known colorectal cancer underwent 18F-FDG-PET/CT for staging or restaging.

Results

Of the 73 patients 26 patients underwent PET/CT for staging and 47 for restaging. 266 metastases could be detected in 60 patients. Contrast-enhanced PET/CT had a lesion-based sensitivity of 100%, contrast-enhanced CT of 91% and PET of 85%. PET/CT identified 2 lesions as false positive. PET/CT could also reach a patient-based sensitivity of 100%, which was superior to contrast-enhanced CT and PET.

Conclusion

Our study clearly demonstrated the added value of contrast-enhanced PET/CT in staging and restaging patients with colorectal cancer over CT and PET alone.     

F-FDG-PET/CT in staging,restaging, and treatment response assessment of male breast cancer

Purpose

Male breast cancer (BC) is a rare disease, with patterns different from those found in women. Most tumors are detected at more advanced stages than in women. The aim of this study was to analyze the performance of [18F]fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) in staging, restaging, and therapy response assessment.

Methods

We performed a systematic analysis in the database of Saint-Louis Hospital to identify male patients with BC referred for PET/CT. ¹⁸F-FDG-PET/CT findings considered suspicious for malignancy were compared to biopsy results, further work-up and/or patient follow-up of at least 6 months. Performances of ¹⁸F-FDG-PET/CT were compared to that of conventional imaging (CI) using the McNemar test. The impact of PET/CT on management was evaluated.

Results

During 6 consecutive years, among 12,692 ¹⁸F-FDG-PET/CT oncology studies, 30 were performed in 15 men with BC: 7 examinations for initial staging, 11 for restaging, and 12 for response assessment. Tumors profile was ER+ and one had HER2 overexpression. PET/CT sensitivity, specificity, positive predictive value, negative predictive value and accuracy to detect distant metastases were 100%, 67%, 86%, 100% and 89%, respectively. PET/CT was more informative than CI in 40% of studies (p = 0.03; 95% confidence interval: 3.26 – 40%). Findings from ¹⁸F-FDG-PET/CT led to modification in the planned treatment in 13/30 cases (43%).

Conclusion

Although all the tumors were ER+, primary lesions and metastases were diagnosed with high sensitivity. ¹⁸F-FDG-PET/CT seems to be a powerful imaging method to perform staging, restaging and treatment response assessment in male patients with BC.     

Patterns of pulmonary tuberculosis on FDG-PET/CT

Objective

This study aims to describe patterns of pulmonary tuberculosis (TB) on FDG-PET/CT.

Methods

All patients with a diagnosis of TB and who underwent FDG-PET/CT between January 2009 and June 2010 were included. Clinical, biological and imaging data were reviewed. TB was proven either on bacteriological or histopathological studies (n = 13) or on a clinical and imaging basis (n = 3).

Results

Sixteen patients (11 men; median age 56, range 22–84 years) were included. Two distinct patterns were identified. In the lung pattern (9/16), patients had predominantly pulmonary symptoms (6/9 patients, 67%) with a parenchymal involvement: uptakes on lung consolidation ± cavitation surrounded by micronodules. Mediastino-hilar lymph nodes were slightly enlarged (15 mm, 10–27) with moderate uptake (3.9, 2.5–13.4). In the lymphatic pattern (7/16), patients had predominantly systemic symptoms (5/7 cases, 71%) and all had extra-thoracic involvement. Mediastino-hilar lymph nodes were more enlarged (30 mm, 18–35, p = 0.03) and with higher uptake (6.8, 5.7–16.8, p = 0.034) than in the lung pattern.

Conclusion

We identified two distinct patterns of pulmonary TB on FDG-PET/CT. The lung pattern related to a restricted and slight hypermetabolic infection and the lymphatic pattern related to a systemic and intense infection. Combined interpretation of PET and CT findings improves the specificity of images, especially for the lung pattern.     

Prospective assessment of 18F-FDG PET/CT in detection of recurrent ovarian cancer

Objective

To assess the use of positron emission tomography (PET)/computed tomography (CT) in patients with suspected ovarian cancer recurrence and describe the distribution of metastasis.

Patients and methods

This study included (39) patients suspected to have recurrent ovarian malignancy. This suspicion was either clinically, radiologically or due to raised CA-125 levels. All patients underwent 18F-FDG PET/CT, surgery was performed within 8 weeks of imaging studies. Surgical and/or histopathological examinations were available in 31 patients, and clinical, radiological and CA 125 serum level follow up in 8 patients.

Results

The overall lesion-based sensitivity, specificity, and accuracy of PET/CT for revealing recurrent ovarian carcinoma were 90%, 98% and 97%, respectively. The patient – based sensitivity, specificity, and accuracy of PET/CT were 97%, 75% and 95%, respectively.

Conclusion

18F-FDG PET/CT is a useful tool for evaluating the recurrence of ovarian cancer after first-line therapy in patients with a high risk of relapse, equivocal radiologic findings, increased or normal levels of serum CA-125. It can more accurately diagnose and localize recurrence, hence decreasing the rate of second look surgery and changing treatment plan.