Predictive value of metabolic activity detected by pre-operative 18F FDG PET/CT in ampullary adenocarcinoma

In ampullary adenocarcinoma cases, the clinical effects of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) have not yet been well-studied, unlike other prognostic factors that have been reported till date. This study aimed to investigate the clinical impact of maximum standardized uptake value (SUVmax) in predicting the prognosis of ampullary adenocarcinoma.Thirty-eight patients who underwent pre-operative ¹⁸F-FDG PET/CT and curative-intent resection of ampullary adenocarcinoma at Pusan National University Hospital (Pusan, South Korea) between 2008 and 2017 were retrospectively analyzed in this study. We evaluated the clinicopathologic outcomes according to the SUVmax using univariate and multivariate Cox proportional hazard regression analyses and receiver operating characteristic analysis to arrive at a cutoff value.Lymph node metastasis was detected in 9 patients, and 15 patients experienced a recurrence during the follow-up period. Among 38 patients, 33 showed an increased FDG uptake by the main tumor. SUVmax of 4.55 was selected as a significant independent predictive factor for patient survival along with poor tumor differentiation and high neutrophil-to-lymphocyte ratio in multivariate analysis (P = .016, hazard ratio = 5.040). Patients with SUVmax under 4.55 exhibited significantly longer overall survival than the rest (<4.55 vs ≥4.55), and the 5-year overall survival was 82.8% versus 57.4% (P = .049).SUVmax of 4.55 on ¹⁸F-FDG PET/CT could be a predictive factor for tumor biology and long-term survival in patients with ampullary adenocarcinoma. Nevertheless, considering the cost aspect and its limited prognostic effect, this study seems to require more patient and multicenter studies.     

Necrosis on pre-radiotherapy 18F-FDG PET/CT is a predictor for complete metabolic response in patients with non-small cell lung cancer

To investigate necrosis on pre-radiotherapy (RT) ¹⁸F-FDG PET/CT (PET_NECROSİS) as a predictor of complete metabolic response (CMR) in patients with non-small cell lung cancer (NSCLC).We evaluated patients with inoperable stage I–III NSCLC who underwent pre- and post-radiotherapy ¹⁸F-FDG PET/CT. The relationship between CMR and PET_NECROSIS, SUVmax, gross tumor volume calculated with ¹⁸F-FDG PET/CT (GTV_PET-CT), tumor size, histology, metabolic tumor volume (MTV), and RT dose was assessed using logistic regression analysis. To evaluate necrosis on ¹⁸F FDG PET/CT, we drew a region of interest (ROI) in the area showing visually very low/or no fluorodeoxyglucose (FDG) uptake on PET images. If the SUVmax was lower than the blood pool SUVmax and showed significantly lower attenuation (10–30 Hounsfield units [HU]) from the surrounding tissue on non-intravenous contrast-enhanced low-dose correlative CT, we defined it as necrotic (PET_NECROSİS).Fifty-three patients were included in this study. The mean age was 68.1 ± 9.8 years. Twenty-one patients had adenocarcinoma, and 32 had squamous cell carcinoma. All parameters were independent of histologic status. Multivariate logistic regression analysis showed that SUVmax ≤11.6 vs >11.6, (P = .003; OR, 7.670, 95CI%: 2.013–29.231) and PET_NECROSİS absence/presence were independent predictors for CMR (P = .028, OR: 6.704, 95CI% 1.214–30.394).The necrosis on ¹⁸F FDG PET/CT and SUVmax > 11.6 could be an imaging marker for the complete metabolic response after definitive chemoradiotherapy or definitive RT alone in patients with NSCLC.     

Clinical value of 18F-fluoro-dexoxyglucose positron emission tomography/computed tomography in patients with adult-onset Still's disease: A seven-case series and review of the literature

Abstract

Objectives. While there are a few reports describing 18F-fluoro-dexoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) findings in patients with adult-onset Still's disease (AOSD), no summary report has yet been published. In this study, we evaluated the usefulness of FDG-PET/CT for diagnosis and activity evaluation in patients with AOSD by summarizing the findings of our patients and those reported in the literature.

Methods. Seven consecutive AOSD patients who had undergone PET/CT at our department between 2007 and 2012 were included. We evaluated FDG uptake for characteristic findings in patients with AOSD. In addition, we reviewed the literature on seven previously reported AOSD patients who had undergone PET/CT.

Results. FDG accumulation was positive mainly in the bone marrow (100%), spleen (90.9%), lymph nodes (80.0%) and joints (75.0%). In addition, FDG uptake was positive in the pericardium, pleura, salivary glands, eyelids, muscle and major blood vessels. Six patients underwent follow-up FDG PET/CT for evaluation of treatment efficacy. Follow-up PET/CT showed diminished FDG accumulation in the bone marrow, spleen and lymph nodes, with maximum standardized uptake value (SUV_max) being substantially reduced from 4.03 ± 0.95 to 2.20 ± 0.75 (p = 0.04), 4.04 ± 1.10 to 2.55 ± 1.13 (p = 0.04) and 5.63 ± 4.99 to 2.10 ± 1.91 (p = 0.11), respectively. No significant correlation was found between SUV_max in each lesion and the laboratory data, except for a significant correlation between lactate dehydrogenase (LDH) and spleen SUV.

Conclusions. FDG-PET/CT is useful for long-term assessments of AOSD activity in individual patients. However, PET/CT findings alone are not sufficient to make a differential diagnosis of AOSD versus malignant lymphoma.     

Diagnostic value for extrahepatic metastases of hepatocellular carcinoma in positron emission tomography/computed tomography scan

AIM: To evaluated the value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan in diagnosis of hepatocellular carcinoma (HCC) and extrahepatic metastases.METHODS: A total of 138 patients with HCC who had both conventional imaging modalities and ¹⁸F-FDG PET/CT scan done between November 2006 and March 2011 were enrolled. Diagnostic value of each imaging modality for detection of extrahepatic metastases was evaluated. Clinical factors and tumor characteristics including PET imaging were analyzed as indicative factors for metastases by univariate and multivariate methods.RESULTS: The accuracy of chest CT was significantly superior compared with the accuracy of PET imaging for detecting lung metastases. The detection rate of metastatic pulmonary nodule ≥ 1 cm was 12/13 (92.3%), when < 1 cm was 2/10 (20%) in PET imaging. The accuracy of PET imaging was significantly superior compared with the accuracy of bone scan for detecting bone metastases. In multivariate analysis, increased tumor size (≥ 5 cm) (P = 0.042) and increased average standardized uptake value (SUV) uptake (P = 0.028) were predictive factors for extrahepatic metastases. Isometabolic HCC in PET imaging was inversely correlated in multivariate analysis (P = 0.035). According to the receiver operating characteristic curve, the optimal cutoff of average SUV to predict extrahepatic metastases was 3.4.CONCLUSION: ¹⁸F-FDG PET/CT scan is invaluable for detection of lung metastases larger than 1 cm and bone metastases. Primary HCC having larger than 5 cm and increased average SUV uptake more than 3.4 should be considered for extrahepatic metastases.     

Comparison of 18F-FDG PET/CT imaging with different dual time 18F-FDG PET/CT with forced diuresis in clinical diagnosis of prostate cancer

The aim of this study was to compare the capability of different dual time (interval 1, 2, 3, or 4 hours) 18F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) with forced diuresis to diagnose prostate cancer (PCa). A retrospective review of 273 male patients from March 2009 to June 2019, with any focal ¹⁸F-FDG uptake in the prostate gland during PET/CT imaging. Early PET/CT imaging was performed 60 minutes after FDG injection. Delayed imaging was performed 1 to 4 hours after diuretic injection. For prostate lesions with increased ¹⁸F-FDG uptake, a spheroid-shaped volume of interest was drawn, including the entire lesion, and the maximum standard uptake value (SUVmax) of the lesion was measured. The SUVmax > 2.5 after delayed imaging and the retention index > 15% were used as the diagnostic criteria for PET/CT in the diagnosis of PCa. Otherwise, it was diagnosed as the benign prostate disease. The final diagnosis was based on histological examination, associated imaging studies, or/and clinical follow-up. The results of inter-group comparison showed that the SUVmax of 1-, 2-, 3-, and 4-hour delayed imaging after diuresis in PCa group was significantly higher than that in control group (P < .05), but there was no statistical difference in SUVmax of early imaging between PCa and control group (P > .05). And the retention index of PCa group that delayed 1, 2, 3, and 4 hours after diuresis were significantly higher than those of control group, respectively (P < .05). The diagnostic sensitivity of imaging delayed 1, 2, 3, and 4 hours after diuresis was 68.8%, 81.2%, 85.7 %, and 71.4%, the specificity was 52.5%, 74.5%, 70.6%, and 65.0%, and the accuracy was respectively 58.2%, 77.4%, 76.4%, and 67.6%, the positive predictive values were 44.0%, 68.9%, 64.3%, and 58.8%, and the negative predictive value were 75.6%, 85.4%, 88.9%, and 76.5%, respectively. ¹⁸F-FDG PET/CT imaging as an imaging tool lacks certain specificity in the diagnosis of PCa, regardless of whether the imaging is delayed. The main advantage of delayed diuretic imaging in PCa is that it can significantly improve the sensitivity, especially the diagnostic effect delayed 2 hours after diuresis is better.     

Ectopic insulinoma diagnosed by 68Ga-Exendin-4 PET/CT: A case report and review of literature

Rationale:Ectopic insulinomas are extremely rare and challenging to diagnose for clinicians. Precise preoperative localization is essential to successful treatment.Patient concerns:A 23-year-old man presented with a 1-year history of recurrent hypoglycemia.Diagnosis:Examinations in the local hospital did not reveal any pancreatic lesion. After admission, a fasting test and a 5-hour oral glucose tolerance test (OGTT) suggested a diagnosis of endogenous hyperinsulinemic hypoglycemia. Enhanced volume perfusion computed tomography (VPCT) revealed 2 nodules in the tail of the pancreas, a nodule in the gastric antrum, and a nodule in the hilum of the spleen. To differentiate which nodule was responsible for hypoglycemia, we performed ⁶⁸Ga-Exendin-4 PET/CT and ⁶⁸Ga-DOTATATE PET/CT which helped to make a conclusive diagnosis that the lesion in the gastric antrum was an ectopic insulinoma.Interventions:The patient was cured with minimally invasive laparoscopic resection of the tumor.Outcomes:The symptoms were relieved and the blood glucose level remained normal after surgery.Conclusions:This case shows that ⁶⁸Gallium-exendin-4 PET/CT is useful for precise localization and thereby successful treatment of insulinoma, especially for occult insulinomas and those derived from an ectopic pancreas.     

Cerebellum/liver index in pretherapeutic 18F-FDG PET/CT as a predictive marker of progression-free survival in follicular lymphoma treated by immunochemotherapy and rituximab maintenance

The purpose of this study was to investigate the value of the “cerebellum/ liver index for prognosis” (CLIP) as a new prognostic marker in pretherapeutic ¹⁸F-Fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) in patients with follicular lymphoma treated by immunochemotherapy and rituximab maintenance, focusing on progression-free survival (PFS).Clinicobiological and imaging data from patients with follicular lymphoma between March 2010 and September 2015 were retrospectively collected and 5-year PFS was determined. The conventional PET parameters (maximum standardized uptake value and total metabolic tumor volume) and the CLIP, corresponding to the ratio of the cerebellum maximum standardized uptake value over the liver SUVmean, were extracted from the pretherapeutic ¹⁸F-FDG PET.Forty-six patients were included. Eighteen patients (39%) progressed within the 5 years after treatment initiation. Five-year PFS was 78.6% when CLIP was >4.0 and 42.0% when CLIP was <4.0 (P = .04). CLIP was a significant predictor of PFS on univariate analysis (hazard ratio 3.1, P = .049) and was near-significant on multivariate analysis (hazard ratio 2.8, P = .07) with ECOG PS as a cofactor.The CLIP derived from pretherapeutic ¹⁸F-FDG PET seems to be an interesting predictive marker of PFS in follicular lymphoma treated by immunochemotherapy and rituximab maintenance. These results should be evaluated prospectively in a larger cohort.     

Precise characterization of a solitary pulmonary nodule using tumor shadow disappearance rate-corrected F-18 FDG PET and enhanced CT

We aimed to characterize solitary pulmonary nodule (SPN) using imaging parameters for F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) or enhanced CT corrected by tumor shadow disappearance rate (TDR) to reflect the tissue density.We enrolled 51 patients with an SPN who underwent PET/CT and chest CT with enhancement. The FDG uptake of SPN was evaluated using maximum standardized uptake value (SUVmax) on PET/CT. The mean Hounsfield unit (HU) for each SPN was evaluated over the region of interest on nonenhanced and enhanced CT images. The change in mean HU (HUpeak-pre) was quantified by subtracting the mean HU of the preenhanced CT from that of the post-enhanced CT. TDR was defined as the ratio of the tumor area, which disappears at a mediastinal window, to the tumor area of the lung window. We investigated which parameters (SUVmax or HUpeak-pre) could contribute to the characterization of SPN classified by TDR value and whether diagnostic performance could be improved using TDR-corrected imaging parameters.For SPN with higher tissue density (TDR <42%, n = 22), high value of SUVmax (≥3.1) was a significant factor to predict malignancy (P = .006). High value of HUpeak-pre (≥38) was a significant factor to characterize SPN (P = .002) with lower tissue density (TDR ≥42%, n = 29). The combined approach using TDR-corrected parameters had better predictive performance to characterize SPN than SUVmax only (P = .031).Applying imaging parameters such as SUVmax or HUpeak-pre in consideration of tissue density calculated with TDR could contribute to accurate characterization of SPN.     

18F-FDG PET/CT imaging for a gastrointestinal mantle cell lymphoma with multiple lymphomatous polyposis

Multiple lymphomatous polyposis(MLP)is an uncommon type of gastrointestinal lymphoma characterized by the presence of multiple polyps along the gastrointestinal tract.Most of this entity is in fact considered the counterpart of gastrointestinal tract involvement for mantle cell lymphoma(MCL).To our knowledge,there have been no reports on[fluorine-18]-fluorodeoxy-glucose(18F-FDG)-positron emission tomography(PET)/computed tomography(CT)imaging for gastrointestinal MCL with MLP.We present the results of 18F-FDG PET/CT imaging in a patient with gastrointestinal tract involvement of MCL showing continuous MLP from the stomach to the rectum and intestinal intussusception.FDG-PET/CT findings were false negative in typical MLP spreading widely over the gastrointestinal tract,but uptake was noted in large lesions with deep infiltration considered atypical as MLP.On FDG-PET/CT imaging,the Ki-67proliferative index,which is a cell proliferation marker,showed neither correlation with the presence of uptake nor the maximum standardized uptake value.     

Clinical impact of 11C-Pittsburgh compound-B positron emission tomography in addition to magnetic resonance imaging and single-photon emission computed tomography on diagnosis of mild cognitive impairment to Alzheimer's disease

This study aimed to evaluated the clinical impact of adding [¹¹C] Pittsburgh compound-B (¹¹C-PiB) PET for clinical diagnosis of mild cognitive impairment (MCI) to Alzheimer''s disease (AD) dementia.Twenty six (mean age 78.5 ± 5.18 years, 21 females) AD (n = 7), amnestic MCI (n = 12), non-amnestic MCI (n = 3), vascular dementia, progressive supranuclear palsy (PSP) with frontotemporal dementia (FTD), FTD (n = 1 each), and normal (n = 1) patients underwent ¹¹C-PiB-PET, MRI, and SPECT scanning. ¹¹C-PiB-PET was compared with MRI and SPECT for clinical impact.¹¹C-PiB-PET showed positivity in 6, 9, and 0 of the AD, amnestic MCI, and non-amnestic MCI patients, respectively, and 0 of those with another disease. Parahippocampal atrophy at VSASD was observed in 5 AD patients, 6 amnestic and PiB-positive MCI patients, 1 amnestic and PiB-negative MCI patient, and 1 vascular dementia patient. Parietal lobe hypoperfusion in SPECT findings was observed in 6, 4, and 2 of those, respectively, as well as 1 each of non-amnestic MCI, vascular dementia, and normal cases. Sensitivity/specificity/accuracy for selecting PiB-positive patients among the 15 MCI patients for ¹¹C-PiB-PET were 100% (9/9)/100% (6/6)/100% (15/15), for VSRAD were 66.7% (6/9)/83.3% (5/6)/73.3% (11/15), and for SPECT were 44.4% (4/9)/50.0% (3/6)/46.7% (7/15), while those were 88.9% (8/9)/33.3% (2/6)/66.7% (10/15)/for combined VSRAD and SPECT. ¹¹C-PiB-PET accuracy was significantly higher than that of SPECT.¹¹PiB-PET alone may be useful for selecting patients who will progress from MCI to AD in the future, although follow-up study is necessary to clarify the outcome of MCI patients.     

Primary splenic epithelioid hemangioendothelioma with diffuse metastases revealed by FDG PET/CT imaging: A case report

Rationale:Epithelioid hemangioendothelioma (EHE) is a rare low-to-intermediate grade malignant vascular neoplasm. We report a primary splenic EHE with diffused metastasis who underwent ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). Our case emphasizes that EHE should be considered a differential diagnose of ¹⁸F-FDG-avid splenic malignancies.Patient concerns:A 39-year-old man presented with abdominal distension and chest distress for 20 days and lumbago for 2 days. Transthoracic echocardiography suggested a large amount of pericardial effusion. Contrast-enhanced CT imaging showed splenomegaly with multiple low-density nodules with ring enhancement. A large irregular mass was also found in the right superior mediastinum with heterogeneous density and enhancement. ¹⁸F-FDG PET/CT imaging revealed splenomegaly, filled with intense hypermetabolic nodules and masses. And multiple regions of increased ¹⁸F-FDG uptake were observed in the mediastinum, left pleura, and bones.Diagnosis:EHE of the spleen.Interventions:Half a month after the diagnosis was confirmed, the patient then underwent chemotherapy, Docetaxel combined with carboplatin, and Endu were administrated every 3 weeks.Outcomes:During the 6-month follow-up period, the patient has finished 4 cycles of chemotherapy combined with 2 months of targeted drug. Efficacy assessment is partial remission through CT imaging, and clinical symptoms of patient improved significantly.Lessons:Primary splenic EHE is extremely rare, especially with diffuse systemic metastasis. Our report suggested that EHE should be considered a differential diagnosis of ¹⁸F-FDG-avid splenic malignancies. Furthermore, ¹⁸F-FDG PET/CT plays critical role in staging and accessing disease extent of EHE.     

Spectrum of FDG uptake in large (>10 cm) esophageal leiomyomas

Esophageal leiomyomas are rare benign tumors that can be treated successfully with limited surgical resection. It is occasionally important to distinguish leiomyomas from more aggressive submucosal esophageal tumors, most notably gastrointestinal stromal tumors (GISTs). GISTs have a worse prognosis, particularly when they are large (>10 cm). Increased uptake of ¹⁸F-fluorodeoxyglucose on positron emission tomography (PET) scans is common in GISTs, potentially allowing PET scanning to differentiate between GIST and benign esophageal tumors. Three patients presented with large (>10 cm) esophageal masses of ranging PET avidity [maximum standardized uptake value (SUVmax) of 1.3–10.1]. All were treated surgically and histologically confirmed to be esophageal leiomyomas. Unfortunately, the wide range of PET uptake precludes PET scanning from differentiating large leiomyomas from more aggressive lesions.     

The value of endobronchial ultrasound-guided transbronchial needle aspiration, 18-fluorodeoxyglucose positron emission tomography/computed tomography,and ultrasonography imaging techniques in the diagnosis of mediastinal and/or hilar malignant,anthracotic, and other benign lymph nodes

Introduction:Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a simple, reliable, minimally invasive and effective procedure. However, a surgical technique may be required, if the results are negative. Therefore, there is a need for new studies to increase the diagnostic value of EBUS-TBNA and provide additional information to guide the biopsy in performing the procedure. Here, we aimed to investigate the diagnostic value of EBUS-TBNA and 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosis of hilar and/or mediastinal lymph nodes (LNs). It was also aimed to determine the contributions of real-time ultrasonography (USG) images of LNs to distinguishing between the malignant and benign LNs during EBUS-TBNA, and in the diagnosis of anthracotic LNs.Material and Method:In the retrospective study including 545 patients, 1068 LNs were sampled by EBUS-TBNA between January 2015 and February 2020. EBUS-TBNA, 18-FDG PET/CT and images of USG were investigated in the diagnosis of mediastinal and/or hilar malignant, anthracotic and other benign LNs.Results:The sensitivity, specificity, positive predictive value and negative predictive value of EBUS-TBNA were found as 79.5, 98.1, 89.5, and 91.7%, respectively. Mean maximum standardized uptake value (SUVmax) values of 18F-FDG PET/CT were 6.31±4.3 in anthracotic LNs and 5.07 ± 2.53 in reactive LNs. Also, mean SUVmax of malignant LNs was 11.02 ± 7.30 and significantly higher than that of benign LNs. In differentiation of malignant-benign tumors, considering the cut off value of 18F-FDG PET/CT SUVmax as 2.72, the sensitivity and specificity was 99.3 and 11.7%, but given the cut off value as 6.48, the sensitivity, specificity, positive predictive value and negative predictive value was found as 76.5, 64, 20.49, and 78.38% for benign LNs, respectively. Compared LNs as to internal structure and contour features, malignant LNs had most often irregular contours and heterogeneous density. Anthracotic, reactive and other benign LNs were most frequently observed as regular contours and homogeneous density. The difference between malignant and benign LNs was significant.Conclusion:EBUS can contribute to the differential diagnosis of malignant, anthracotic and other benign LNs. Such contributions can guide clinician bronchoscopists during EBUS-TBNA. The triple modality of EBUS-TBNA, 18FDG PET/CT, and USG may increase the diagnostic value in hilar and mediastinal lymphadenopathies.     

Prognostic value of metabolic parameters measured by pretreatment dual-time-point 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with intrahepatic or perihilar cholangiocarcinoma: A STROBE study

The purpose of this study was to determine the glucose metabolism at delay phase measured by pretreatment dual-time-point ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/ computed tomography (CT) provides prognostic information independent of well-known prognostic factors in patients with intrahepatic or perihilar cholangiocarcinoma (ICC or PCC).From July 2012 to December 2017, 55 patients (men 27, women 28, mean age 68 ± 11 years) with pathologically proven ICC or PCC were enrolled in this retrospective study. The dual-time-point ¹⁸F-FDG PET/CT as part of a staging workup was performed in all patients. The patient''s data includes age, sex, serum CA19-9, presence of LN or distant metastasis, early SUVmax (early maximum standardized uptake value [eSUV]), delay SUVmax (delay maximum standardized uptake value [dSUV]), retention index of SUVmax (percent change of maximum standardized uptake values [ΔSUV]), neutrophil to lymphocyte ratio (NLR) and histopathology including pCEA, p53, Ki-67 index. The analysis of the relationship between metabolic parameters and survival was done using the Kaplan–Meier curve and Cox proportional hazards regression model.Median survival for all patients was 357 days. Median early and delay SUVmax was 5.2 (range: 2.0–21.4) and 6.5 (range 2.7–24.5), respectively. The overall survival was found to be significantly related to eSUV, dSUV, ΔSUV, age, serum CA19-9 and NLR in univariate analysis. In multivariate analysis, dSUV (P = .014, 95%CI; 1.30–10.7, HR 3.74) and ΔSUVmax (P = .037, 95%CI; 1.05–6.12, HR 2.5) were independent factors of overall survival. Kaplan–Meier curve analysis clearly showed the significant difference of overall survival between 2 groups (high eSUV, low eSUV + high ΔSUV vs low eSUV and ΔSUV, P < .001) among the comparisons of the SUV parameters on FDG PET. In the receiver operating characteristic analysis using combinations of the SUV parameters, the 2 groups [eSUV + ΔSUV (P = .0001, area under the curve [AUC] 0.68) and dSUV + ΔSUV (P = .0002, AUC 0.71)] showed significantly larger AUC than the other groups applying eSUV or dSUV alone (AUC 0.61 and AUC 0.68).dSUV and ΔSUV on pretreatment dual-time-point ¹⁸F-FDG PET/CT can be useful parameters in the prediction of survival in patients with ICC or PCC.     

Positron Emission Tomography With 18F-Fluorodeoxyglucose in Patients With Sickle Cell Acute Chest Syndrome

The acute chest syndrome (ACS) is the main cause of mortality among adult patients with sickle cell disease (SCD). Its pathophysiology is still unclear. Using positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose [18F-fluorodeoxyglucose (¹⁸F-FDG)], we explored the relationship between regional lung density and lung metabolism, as a reflection of lung neutrophilic infiltration during ACS.Patients were prospectively enrolled in a single-center study. Dual modality chest PET/computed tomography (CT) scans were performed, with ¹⁸F-FDG emission scans for quantification of regional ¹⁸F-FDG uptake and CT scans with radiocontrast agent to check for pulmonary artery thrombosis. Regional lung ¹⁸F-FDG uptake was quantified in ACS patients and in SCD patients without ACS (SCD non-ACS controls). Maximal (SUVmax) and mean (SUVmean) standardized uptake values were computed.Seventeen patients with ACS (mean age 28.3 ± 6.4 years) were included. None died nor required invasive mechanical ventilation. The main lung opacity on CT scans was lower lobe consolidation. Lungs of patients with ACS exhibited higher SUVmax than those of SCD non-ACS controls (2.5 [2.1–2.9] vs 0.8 [0.6–1.0]; P < 0.0001). Regional SUVmax and SUVmean was higher in lower than in upper lobes of ACS patients (P < 0.001) with a significant correlation between lung density and SUVmax (R² = 0.78). SUVmean was higher in upper lobes of ACS patients than in lungs of SCD non-ACS controls (P < 0.001). Patients with SUVmax >2.5 had longer intensive care unit (ICU) stay than others (7 [6–11] vs 4 [3–6] days; P = 0.016).Lungs of patients with ACS exhibited higher ¹⁸F-FDG uptake than SCD non-ACS controls. Lung apices had normal aeration and lower ¹⁸F-FDG uptake than lung bases, but higher ¹⁸F-FDG uptake than lungs of SCD non-ACS controls. Patients with higher lung ¹⁸F-FDG uptake had longer ICU stay than others.     

Positron emission tomography/computed tomography and endobronchial ultrasound-guided transbronchial needle aspiration to evaluate the status of N2 in preoperative non-small cell lung cancer: a diagnostic test

BackgroundAs a minimally invasive method, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) was more accurate than non-invasive methods such as positron emission tomography (PET) and computed tomography (CT) to evaluate the lymph nodes in preoperative non-small cell lung cancer (NSCLC). PET/CT has more anatomical advantages than PET scanning and is more accurate in lung cancer staging. However, no relevant studies have comparatively evaluated PET/CT and EBUS-TBNA for NSCLC patients.MethodsA total of 112 patients were included in this retrospective analysis. The golden diagnosis of N2 status was postoperative pathological results. In EBUS-TBNA puncture specimens, if clear malignant tumor cells could be seen, the results were taken as positive. In PET/CT image analysis, the CT values, short diameter, and maximum standardized uptake value (SUVmax) of each lymph node were recorded to evaluate N2 status. The results of PET/CT and EBUS-TBNA were compared with the final pathological results, and respective sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated. - Then, the patients were divided into adenocarcinoma group and squamous cell carcinoma group -and the results were calculated and compared with the above method.ResultsThe results showed that EBUS-TBNA had a higher diagnostic value for mediastinal lymph nodes than PET/CT, and the difference was statistically significant (P<0.001). In NSCLC patients, the results showed that the sensitivity (P=0.013), specificity (P<0.001), PPV (P<0.001), NPV (P<0.001), and accuracy (P<0.001) of EBUS-TBNA were higher than that of PET/CT (AUC =0.954 and 0.636, respectively). In adenocarcinoma cases, specificity (P<0.001), PPV (P<0.001), NPV (P<0.001), and accuracy (P<0.001) of EBUS-TBNA were higher than that of PET/CT (AUC =0.957 and 0.596, respectively).In cases with squamous cell carcinoma, specificity (P=0.003), PPV (P<0.001), and accuracy (P<0.001) of EBUS-TBNA were higher than PET/CT (AUC =0.952 and 0.657, respectively).ConclusionsFor preoperative diagnosis of mediastinal lymph node metastases in NSCLC, EBUS-TBNA is more accurate than PET/CT. For those patients with suspected mediastinal lymph node metastasis, EBUS-TBNA should be preferred method to evaluate the status of mediastinal lymph nodes.     

A pilot study on EORTC or PERCIST for the prediction of progression-free survival with nivolumab therapy in advanced or metastatic gastric cancers: A STROBE-compliant article

Recent breakthrough results from immune checkpoint inhibitors (ICIs) have paved the way to a new era of cancer immunotherapy, and have thus led to a paradigm shift of cancer treatment. In particular, inhibition of the antiprogrammed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) axis with ICI, including nivolumab and pembrolizumab, has been emerging as a novel treatment strategy for advanced gastric cancers. An accurate noninvasive assessment of the response to ICI is important for the management of patients with advanced or metastatic gastric cancer.To examine whether the European Organization for Research and Treatment of Cancer (EORTC) and PET Response Criteria in Solid Tumors (PERCIST) are valuable for predicting progression-free survival (PFS) in patients with advanced or metastatic gastric cancers treated with nivolumab.Six patients with advanced or metastatic gastric cancers who underwent ¹⁸F-FDG-PET/computed tomography (CT) scans before, and from 2 to 6 months after initiation of nivolumab therapy between September 2017 and August 2019, were evaluated retrospectively. The correlation between tumor progression and EORTC or PERCIST was assessed with the Fisher''s exact test. The PFS was assessed with the Kaplan–Meier method.Two patients were alive without progression, and the remaining 4 patients exhibited tumor progression. Two patients without progression were classified as partial metabolic response (PMR) patients based on EORTC or PERCIST, while the other 4 patients with progression were classified as progressive metabolic disease (PMD) patients based on EORTC (P = .067), or stable metabolic disease (SMD) patients, or PMD patients based on PERCIST (P = .067).The mean and median PFS of all patients was 12.7 months (95% confidence interval [CI], 4.9–20.4 months) and 5 months (95%CI, 4.0–11.0 months). Two EORTC or PERCIST PMR patients showed significantly longer median PFS compared with 4 non-PMR patients (not reached vs 4.0 months, P = .044). Three PERCIST PMR or SMD patients also showed significantly longer median PFS compared with 3 PMD patients (not reached vs 4.0 months, P = .022). These results suggest that EORTC or PERCIST has the potential to predict PFS of patients with advanced or metastatic gastric cancers treated by nivolumab and further studies are needed to determine its value in larger study populations.     

FDG PET/CT for evaluating systemic arterial inflammation induced by anthracycline-based chemotherapy of Hodgkin lymphoma: A retrospective cohort study

To evaluate arterial fluorodeoxyglucose (FDG) uptake as a marker of arterial inflammation in multiple vascular beds in patients treated with anthracycline-based chemotherapy for Hodgkin lymphoma (HL).We used maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) to quantify arterial FDG uptake in the carotid artery, ascending aorta, abdominal aorta, and femoral artery obtained on positron emission tomography/computed tomography (PET/CT) imaging performed at baseline before chemotherapy and after completion of chemotherapy in patients with HL treated with an anthracycline-containing regimen. We compared the SUVmax and TBR obtained at baseline with that obtained post-chemotherapy for each arterial bed to evaluate the effect of anthracycline-based chemotherapy. We evaluated the effect of cardiovascular risk factors such as human immunodeficiency virus (HIV) infection, smoking, hypertension, and diabetes on the changes in SUVmax and TBR seen in the different arterial beds after anthracycline-based chemotherapy.Fifty-two patients were included with a mean age of 34.56 ± 10.19 years. There were 33 males, and 18 patients were HIV-infected. The mean interval between completion of chemotherapy and follow-up flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scan was 65 weeks. We found no significant difference in arterial FDG uptake measured by SUVmax and TBR in all arterial beds between the pre- and post-chemotherapy FDG PET/CT. There was no significant impact of HIV infection, smoking, and hypertension on the changes in arterial FDG uptake following treatment with anthracycline-based chemotherapy.In patients with HL who were treated with anthracycline-based chemotherapy, we found no significant increase in arterial inflammation measured by FDG PET/CT after an average follow-up period of about 65 weeks since completion of chemotherapy.     

Whole-body fluorodeoxyglucose positron emission tomography/computed tomography in patients with active polymyalgia rheumatica: evidence for distinctive bursitis and large-vessel vasculitis

Abstract

Objectives To investigate fluorodeoxyglucose (FDG) accumulation in large joints, bursas, and large vessels in patients with polymyalgia rheumatica (PMR) using 18-FDG positron emission tomography/computed tomography (PET/CT) and to differentiate PMR from similar diseases.

Methods Fourteen untreated patients with active PMR and 17 control patients with rheumatoid arthritis (n = 11) or other active rheumatic diseases (n = 6) underwent 18-FDG PET/CT. FDG uptake in large joints, bursas and vertebral spinous processes was evaluated by calculating maximum standardised uptake values and by visual scoring (scale 0–4). PET scan images were scored in seven vascular regions, and total vascular scores (range 0–21) were calculated.

Results Polymyalgia rheumatica patients showed increased FDG uptake in ischial tuberosities, greater trochanters, and lumbar spinous processes. Positive results at two or more of these sites showed high sensitivity (85.7%) and specificity (88.2%) for the diagnosis of PMR, and shoulder or hip-joint involvement showed low disease specificity. High FDG accumulations were found in the aortas and subclavian arteries of two PMR patients who were asymptomatic for temporal arteritis and scanty synovium and perisynovium, based on FDG uptake. PET/CT images of the 12 PMR patients without apparent vascular involvement showed synovitis and/or perisynovitis.

Conclusions Fluorodeoxyglucose-PET/CT may be useful for the detection of PMR lesions, which are difficult to identify using other methods.