The utility of positron emission tomography/computed tomography in the staging of extranodal natural killer/T-cell lymphoma

Natural killer (NK)/T-cell lymphoma cases are rarely discovered using positron emission tomography/computed tomography (PET/CT). We compared the utility of PET/CT and that of conventional methods (CMs; CT with IV contrast, biopsies from primary sites, and bone marrow examinations) in the staging of extranodal NK/T-cell lymphoma. Nineteen untreated patients with extranodal NK/T-cell lymphoma at three institutions were analyzed. PET/CT and CMs were applied for initial workups following diagnosis. PET/CT and CMs were compared and evaluated for their ability to detect tumor lesions and their influence on the staging and treatment strategies. In total, 116 lesions were detected by CM and PET/CT. Using PET/CT, 108 lesions (93%) were discovered. The number of nodal lesions was 28: all were positive by PET/CT and 26 (93%) by CMs. The number of extranodal lesions was 89: 84 (94%) and 54 (61%) lesions were positive by PET/CT and CMs, respectively. PET/CT was superior to CMs in detecting cutaneous lesions [31/31 lesions (100%) vs. 20/31 lesions (65%), respectively; P=0.042]. Bone marrow involvement was confirmed pathologically in only seven patients; four cases (57%) were positive by PET/CT. Using CMs, ten patients (53%) were stages I-II and nine (47%) were stages III-IV. Using PET/CT, eight patients (42%) were in stages I-II and 11 (58%) were in stages III-IV. PET/CT findings altered the stage and treatment strategy in two cases (11%). Our study demonstrated that PET/CT is a useful tool for detecting extranodal lesions in NK/T-cell lymphoma, particularly cutaneous lesions. PET/CT may therefore influence future staging and treatment strategies.     

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.     

Comparison Between ESC and Duke Criteria for the Diagnosis of Prosthetic Valve Infective Endocarditis

ObjectivesThe primary objective was to assess the value of the European Society of Cardiology (ESC) criteria, including ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) in prosthetic valve infective endocarditis (PVE). Secondary objectives were: 1) to assess the reproducibility of ¹⁸F-FDG-PET/CT; 2) to compare its diagnostic value with that of echocardiography; and 3) to assess the diagnostic value of the presence of a diffuse splenic uptakeBackground¹⁸F-FDG PET/CT has been added as a major criterion in the ESC 2015 infective endocarditis (IE) guidelines, but the benefit of the ESC criteria has not been prospectively compared with the conventional Duke criteria.MethodsBetween 2014 and 2017, 175 patients with suspected PVE were prospectively included in 3 French centers. After exclusion of patients with uninterpretable ¹⁸F-FDG PET/CT, 115 patients were evaluated, including 91 definite and 24 rejected IE, as defined by an expert consensus.ResultsCardiac uptake by ¹⁸F-FDG PET/CT was observed in 67 of 91 patients with definite PVE and 6 with rejected IE (sensitivity 73.6% [95% confidence interval (CI): 63.3% to 82.3%], specificity 75% [95% CI: 53.3% to 90.2%]). The ESC 2015 classification increased the sensitivity of Duke criteria from 57.1% (95% CI: 46.3% to 67.5%) to 83.5% (95% CI: 74.3% to 90.5%) (p < 0.001), but decreased its specificity from 95.8% (95% CI: 78.9% to 99.9%) to 70.8% (95% CI: 48.9% to 87.4%). Intraobserver reproducibility of ¹⁸F-FDG PET/CT was good (kappa = 0.84) but interobserver reproducibility was less satisfactory (kappa = 0.63). A diffuse splenic uptake was observed in 24 (20.3%) patients, including 23 (25.3%) of definite PVE, and only 1 (4.2%) rejected PVE (p = 0.024).Conclusions¹⁸F-FDG PET/CT is a useful diagnostic tool in suspected PVE, and explains the greater sensitivity of ESC criteria than Duke criteria. However, ¹⁸F-FDG PET/CT also presents with important limitations concerning its feasibility, specificity, and reproducibility. Our study describes for the first time a new endocarditis criterion, that is, the presence of a diffuse splenic uptake on ¹⁸F-FDG PET/CT.     

Incidental carcinomas detected by PET/CT scans in patients with malignant lymphoma

According to the international working group response criteria for malignant lymphoma revised in 2007, 18F-fluorodeoxyglucose positron emission tomography (¹⁸FDG-PET) combined with or without computed tomography (CT) is recommended for pre-treatment staging and response assessment among patients with diffuse large B-cell lymphoma and Hodgkin lymphoma. Recently, along with the widespread use of PET/CT, unexpected uptake and accumulation of ¹⁸FDG has been reported. Discussed in the present report are patients with malignant lymphoma and second primary carcinomas that were incidentally found by PET/CT. A total of 497 consecutive PET/CT were performed on 290 patients with malignant lymphoma in our institution from April 2008 through March 2010. Eight patients (2.8%) had pathologically confirmed second primary carcinomas consisting of 4 colon cancers, 3 lung cancers, and 1 pancreatic cancer. Two cases were diagnosed at the initial staging, and the others were detected after treatment for lymphoma. It is noteworthy that PET revealed high accumulations of ¹⁸FDG in 5 (62.5%) of the 8 patients without corresponding tumors in conventional CT. All of the 4 patients with colon carcinoma underwent curative surgery. The present study suggests that incidental findings by PET in malignant lymphoma can lead to early detection and successful treatment of second malignancies.     

Development of the AL-O-A Score for Delirium Screening in Acute Internal Medicine: a Monocentric Prospective Study

BackgroundDelirium occurs frequently in acute internal medicine wards and may worsen the patient’s prognosis; it deserves a fast, systematic screening tool.ObjectiveDevelop a delirium screening score for inpatients admitted to acute internal medicine wards.DesignA monocentric prospective study between November 2019 and January 2020.ParticipantsTwo hundred and seventeen adult inpatients.Main MeasuresWithin 48 h of hospital admission, physicians administered an index test to participants which explored potential predictors associated with the fluctuation of mental state, inattention, disorganised thinking and altered level of consciousness. On the same day, patients underwent a neuropsychological evaluation (reference standard) to assess for delirium. The score was constructed using a backward stepwise logistic regression strategy. Areas under the receiver operating curves (AUC) and calibration curves were drawn to calculate the score’s performance. The score was tested on subgroups determined by age, sex and cognitive status.ResultsThe AL-O-A score (“abnormal or fluctuating ALertness, temporospatial Orientation and off-target Answers”) showed excellent apparent (AUC 0.95 (95% CI 0.91–0.99)) and optimism-corrected discrimination (AUC 0.92 (95% CI 0.89–0.96)). It performed equally well in subgroups with and without cognitive impairment (AUC 0.93 (95% CI 0.88–0.99) vs 0.92 (95% CI 0.80–0.99)); in men and women (AUC 0.96 (95% CI 0.94–0.99) vs 0.95 (95% CI 0.89–0.99)); and in patients younger and older than 75 years old (AUC 0.98 (95% CI 0.95–0.99) vs 0.93 (95% CI 0.87–0.99)).ConclusionsA simple, 1-min screening test (AL-O-A score), even administered by an untrained professional, can identify delirium in internal medicine patients.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06502-w.KEY WORDS: delirium, internal medicine, inpatients, adult, prospective study, score     

Prognostic Value of the Sum of Metabolic Tumor Volume of Primary Tumor and Lymph Nodes Using 18F-FDG PET/CT in Patients With Cervical Cancer

This is an observational study to determine the most relevant parameter of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for predicting recurrence in cervical cancer.Fifty-six patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIB-IVA cervical cancer who underwent pretreatment ¹⁸F-FDG PET/CT were enrolled. PET parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of both primary tumor and pelvic and/or para-aortic lymph nodes were analyzed. SUVmax-S was defined as the sum of the SUVmax of primary tumor and the higher SUVmax of either pelvic or para-aortic lymph nodes. MTV-S was defined as the sum of the MTV of primary tumor and pelvic and para-aortic lymph nodes. TLG-S was calculated in the same way as MTV-S. We evaluated the relationship between these PET parameters and recurrence-free survival (RFS).Univariate analysis revealed that higher FIGO stage (hazard ratio [HR] = 5.61, 95% confidence interval [CI]: 1.68–18.68, P = 0.005), lymph node metastasis (HR = 3.42, 95% CI: 1.08–10.84, P = 0.037), MTV of primary tumor >47.81 cm³ (HR = 6.20, 95% CI: 1.35–28.48, P = 0.019), TLG of primary tumor >215.02 (HR = 11.82, 95% CI: 1.52–91.96, P = 0.018), MTV-S > 59.01 cm³ (HR = 8.24, 95% CI: 1.80–37.77, P = 0.007), and TLG-S > 224.15 (HR =  13.09, 95% CI: 1.68–101.89, P = 0.014) were associated with RFS. In multivariate analysis, FIGO stage (HR = 4.87, 95% CI: 1.38–17.18, P = 0.014) and MTV-S > 59.01 cm³ (HR = 7.37, 95% CI: 1.54–35.16, P = 0.012) were determined to be independent predictive factors for RFS.Our preliminary results reveal that MTV-S is an independent prognostic factor for RFS in patients with cervical cancer treated by definitive chemoradiotherapy.     

鼻型结外NK/T细胞淋巴瘤PET/CT表现及临床分析

目的:用18F-FDG PET/CT精确揭示鼻型结外NK/T细胞淋巴瘤患者的病灶,探讨病变范围与相关临床指标的关系。方法:22例初诊鼻型结外NK/T细胞淋巴瘤患者治疗前行18F-FDG PET/CT检查,分析鼻、咽部及全身病灶累及范围及播散规律,并分析不同病变范围患者之间ALB、LDH、β2-MG、SUVmax、B症状发生率之间的差异。结果:18F-FDG PET/CT发现每位患者至少有一处病灶,原发病灶在鼻腔、鼻咽、口咽部者分别占81.9%、9.1%、9.1%。病变累及最多的部位为鼻腔(95.5%,21/22)、鼻咽(54.5%,12/22)、左颈部淋巴结(40.9%,9/22)、右颈部淋巴结(40.9%,9/22)、口咽(36.4%,8/22)等。鼻、咽部原发病灶可向邻近部位播散,也可沿淋巴结群依次播散,还可以跳跃方式向远处器官播散。病灶范围较广者组,SUVmax值显著增加,血清β2-MG升高者比例也显著增加。结论:18F-FDG PET/CT能精确发现鼻型结外NK/T细胞淋巴瘤患者鼻、咽部及全身病灶,血清β2-MG水平也能反映病灶的累及范围。     

Evaluation of Dual Time Point Imaging 18F-FDG PET/CT in Differentiating Malignancy From Benign Gastric Disease

To assess the clinical value of dual time point imaging (DTPI) fluorine-18fludeoxyglucose (18F-FDG) positron emission tomography (PET)/CT in differentiating malignancy and benign disease of patients with focally increased gastric uptake.Patients who present focally increased 18F-FDG uptake in gastric wall on conventional PET/CT imaging received delayed imaging. PET/CT scans were acquired at 1 and 2 hours (early and delayed imaging) after 18F-FDG injection. The maximum standardized uptake value (SUV) was calculated. The SUVmax of the early and delayed imaging acquisition were signed S1 and S2, respectively. The receiver operating characteristic curve (ROC) of the S1, S2, and the retention index (RI) were drawn to find the best cut-off point value for differential diagnosis. Sensitivity, specificity, Youden index, and the area under the curve (AUC) were calculated, respectively.From September 2010 to May 2015, 74 patients (56 male and 18 female; age of 57 ± 12 years; range, 32–86 years) referring for areas of focally increased uptake of 18F-FDG in gastric wall received delayed imaging. The S1 was 5.0 ± 1.4 (range, 1.9–11.3), and S2 was 5.9 ± 2.7 (range, 1.0–16.3). The SUVmax were increased in 52 patients in delayed imaging, with 85% (44/52 cases) appeared malignant; decreased in 20 patients, and 90% (18/20 cases) were benign; 2 patients of benign had not changed. The change of SUVmax between malignant and benign was significant difference (t = −5.785, P = 0.000).Taking the S1, S2, and RI higher than 4.6%, 5.1%, and 13% as positive diagnostic criteria, the sensitivity were 65.2%,87.0%, and 87.0%, respectively; the specificity were 64.3%, 82.1%, and 89.3%; the Youden index were 0.332, 0.693, and 0.770; AUC were 0.635 (95% confidence intervals (95% CI) 0.507–0.764), 0.873 (95% CI, 0.786–0.961), and 0.923 (95% CI, 0.854–0.992).DTPI is more precise to distinct malignant from benign gastric diseases compared with conventional imaging, and it is readily accessible.     

Diagnostic accuracy of fluorine-18-fluorodeoxyglucose positron emission tomography in gallbladder cancer: A meta-analysis

AIM: To meta-analyze published data about the diagnostic accuracy of fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) and PET/computed tomography (PET/CT) in the evaluation of primary tumor in patients with gallbladder cancer (GBCa).METHODS: A comprehensive literature search of studies published through 30^th June 2014 regarding the role of ¹⁸F-FDG PET and PET/CT in the evaluation of primary gallbladder cancer (GBCa) was performed. All retrieved studies were reviewed. Pooled sensitivity and specificity of ¹⁸F-FDG PET or PET/CT in the evaluation of primary GBCa were calculated. The area under the summary receiving operator characteristics curve (AUC) was calculated to measure the accuracy of these methods. Sub-analyses considering the device used (PET vs PET/CT) were carried out.RESULTS: Twenty-one studies comprising 495 patients who underwent ¹⁸F-FDG PET or PET/CT for suspicious GBCa were selected for the systematic review. The meta-analysis of 13 selected studies provided the following results: sensitivity 87% (95%CI: 82%-92%), specificity 78% (95%CI: 68%-86%). The AUC was 0.88. Improvement of sensitivity and specificity was observed when PET/CT was used.CONCLUSION: ¹⁸F-FDG-PET and PET/CT demonstrated to be useful diagnostic imaging methods in the assessment of primary tumor in GBCa patients, nevertheless possible sources of false-negative and false-positive results should be kept in mind. PET/CT seems to have a better diagnostic accuracy than PET alone in this setting.     

The value of positron emission tomography computed tomography in predicting invasiveness of ground glass nodules: A protocol for systematic review and meta-analysis

Background:The study was conducted to investigate the value of Positron emission tomography computed tomography (PET/CT) in predicting invasiveness of ground glass nodule (GGN) by the method of meta-analysis.Methods:Two researchers independently searched for published literature on PET/CT diagnosis of GGN as of November 30, 2020. After extracting the data, RevMan5.3 was used to evaluate the quality of the included literature. The Stata14 software was used to test the heterogeneity of the original study that met the inclusion criteria, to calculate the combined sensitivity, specificity, positive likelihood ratio and negative likelihood ratio, the prior probability and posttest probability. The summary receiver operator characteristic curve was drawn and the area under the curve was calculated. Using Deeks funnel plot to evaluate publication bias.Results:Five studies were finally included, including 298 GGN cases. The included studies had no obvious heterogeneity and publication bias. The combined sensitivity and specificity of PET/CT for predicting invasive adenocarcinoma presenting as GGN were 0.74 (95% confidence interval [CI]: 0.68–0.79), 0.82 (95% CI: 0.71–0.90), positive likelihood ratio and negative likelihood ratio were 4.1 (95% CI: 2.5–6.9), 0.32 (95% CI: 0.25–0.40), and the diagnostic odds ratio was 13 (95% CI: 7–26). The prior probability is 20%, the probability of GGN being invasive adenocarcinoma when PET/CT was negative was reduced to 7%, and the probability of GGN being invasive adenocarcinoma when PET/CT was positive was increased to 51%. The area under the curve of the summary receiver operator characteristic curve was 0.85.Conclusion:PET/CT has high diagnostic accuracy for invasive adenocarcinoma presenting as GGN.     

18F-FDG PET/CT imaging in the diagnosis of drug-induced lung disease and pulmonary infection in lymphoma

Objective:Lymphoma is a hematological disease with high prevalence. Multi-cycle chemotherapy (CHT) or local radiotherapy is applied usually; however, adverse events have been reported, such as drug-induced lung disease (DILD). Positron emission tomography/computed tomography (PET/CT) is often used to evaluate the lesion, treatment effect, and prognosis of lymphoma. We investigated DILD and pulmonary infection (PI) after multi-cycle CHT in lymphoma patients, to identify DILD and PI, provide guidance for later treatment for them.Methods:In all, 677 patients diagnosed with lymphoma and who underwent CHT were included. These patients underwent ¹⁸fluorodeoxyglucose (¹⁸F-FDG) PET/CT before and after CHT at Shandong Cancer Hospital (affiliated with Shandong University) between April 2015 and November 2019. Fifty patients developed DILD, 41 patients had lung infections; lesion characteristics were analyzed based on clinical characteristics, laboratory examinations, and PET/CT imaging.Results:Among the 677 lymphoma patients, there were 50 cases of DILD, with an incidence rate of 7.4%. PET/CT showed an elevated ¹⁸fluorodeoxyglucose uptake lung background, septal thickening and reticulation, multiple ground glass-like shadows, and grid-shaped blur shadows, which were more common in the lung periphery and under the pleura. The maximum standardized uptake value in the lung was 2.45 ± 0.52. Pulmonary infections occurred in 41 patients, and the maximum standardized uptake value was 4.05 ± 1.42. Age, sex, CHT cycle, Ann-Arbor stage, and lymphocyte levels were not significantly different between DILD and PI patients. Leukocyte and neutrophils showed significant differences; the PI patients had increased laboratory indexes of leukocyte and neutrophils. The mean number of CHT cycles was 4 cycles for DILD and PI.Conclusions:PET/CT imaging has high sensitivity and detection rates for primary and metastatic lymphoma lesions. DILD mostly occurs in the middle and late stages of CHT. Laboratory tests and PET/CT can evaluate the lesions and treatment effects, and provide guidance for subsequent treatment plans for patients.     

Idiopathic CD4 Lymphocytopenia: Clinical and Immunologic Characteristics and Follow-Up of 40 Patients

Idiopathic CD4 T lymphocytopenia (ICL) is a rare and severe condition with limited available data. We conducted a French multicenter study to analyze the clinical and immunologic characteristics of a cohort of patients with ICL according to the Centers for Disease Control criteria.We recruited 40 patients (24 female) of mean age 44.2 ± 12.2 (19–70) years. Patients underwent T-lymphocyte phenotyping and lymphoproliferation assay at diagnosis, and experiments related to thymic function and interferon (IFN)-γ release by natural killer (NK) cell were performed. Mean follow-up was 6.9 ± 6.7 (0.14–24.3) years. Infectious, autoimmune, and neoplastic events were recorded, as were outcomes of interleukin 2 therapy.In all, 25 patients had opportunistic infections (12 with human papillomavirus infection), 14 had autoimmune symptoms, 5 had malignancies, and 8 had mild or no symptoms. At the time of diagnosis, the mean cell counts were as follows: mean CD4 cell count: 127/mm³ (range, 4–294); mean CD8: 236/mm³ (range, 1–1293); mean CD19: 113/mm³ (range, 3–547); and mean NK cell count: 122/mm³ (range, 5–416). Most patients had deficiency in CD8, CD19, and/or NK cells. Cytotoxic function of NK cells was normal, and patients with infections had a significantly lower NK cell count than those without (p = 0.01). Patients with autoimmune manifestations had increased CD8 T-cell count. Proliferation of thymic precursors, as assessed by T-cell rearrangement excision circles, was increased. Six patients died (15%). CD4 T-cell count <150/mm³ and NK cell count <100/mm³ were predictors of death.In conclusion, ICL is a heterogeneous disorder often associated with deficiencies in CD8, CD19, and/or NK cells. Long-term prognosis may be related to initial CD4 and NK cell deficiency.Abbreviations: AIHA = autoimmune hemolytic anemia, CDC = Centers for Disease Control, CMV = cytomegalovirus, cpm = count per minute, CVID = common variable immunodeficiency, CXCR4 = C-X-C chemokine receptor type 4, HIV = human immunodeficiency virus, HLA = human leukocyte antigen, HPV = human papillomavirus, HTLV-1/2 = human T-cell lymphotropic 1/2, ICL = idiopathic CD4 T lymphocytopenia, IFN-γ = interferon-γ, IL = interleukin, JC virus = John Cunningham virus, LPA = lymphocyte proliferation assay, NK = natural killer, P = patient, PBMC = peripheral blood mononuclear cell, Pwd = pokeweed, SI = stimulation index, sj = signal joint, TREC = T-cell rearrangement excision circle     

MRI versus CT for the detection of pulmonary nodules: A meta-analysis

Background:Computed tomography (CT) is the current gold standard for the detection of pulmonary nodules but has high radiation burden. In contrast, many radiologists tried to use magnetic resonance imaging (MRI) to replace CT because MRI has no radiation burden associated. Due to the lack of high-level evidence of comparison of the diagnostic accuracy of MRI versus CT for detecting pulmonary nodules, it is unknown whether CT can be replaced successfully by MRI. Therefore, the aim of this study was to compare the diagnostic accuracy of MRI versus CT for detecting pulmonary nodules.Methods:Electronic databases PubMed, EmBase, and Cochrane Library were systematically searched from their inception to September 2017 to identify studies in which CT/MRI was used to diagnose pulmonary nodules. According to true positive, true negative, false negative, and false positive extracted from the included studies, we calculate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and area under the curve (AUC) using Stata version 14.0 software (STATA Corp, TX).Results:A total of 8 studies involving a total of 653 individuals were included. The pooled sensitivity, specificity, PLR, NLR, and AUC were 0.91 (95% confidence interval [CI]: 0.80–0.96), 0.76 (95%CI: 0.58–0.87), 3.72 (95%CI: 2.05–6.76), 0.12 (95%CI: 0.06–0.27), and 0.91 (95%CI: 0.88–0.93) for MRI respectively, while the pooled sensitivity, specificity, PLR, NLR, and AUC for CT were 1.00 (95%CI: 0.95–1.00), 0.99 (95%CI: 0.78–1.00), 79.35 (95%CI: 3.68–1711.06), 0.00 (95%CI: 0.00–0.06), and 1.00 (95%CI: 0.99–1.00), respectively. Further, we compared the diagnostic accuracy of CT versus MRI and found that compared with MRI, CT shows statistically higher sensitivity (odds ratio [OR] for MRI vs CT: 0.91; 95%CI: 0.85–0.98; P value .010), specificity (OR: 0.82; 95%CI: 0.69–0.97; P value .019), PLR (OR: 0.29; 95%CI: 0.10–0.83; P value 0.02), AUC (OR: 0.91; 95%CI: 0.89–0.94; P value < .001), and lower NLR (OR: 8.72; 95%CI: 1.57–48.56; P value .013).Conclusion:Our study suggested both CT and MRI have a high diagnostic accuracy in diagnosing pulmonary nodules, while CT was superior to MRI in sensitivity, specificity, PLR, NLR, and AUC, indicating that in terms of the currently available evidence, MRI could not replace CT in diagnosing pulmonary nodules.     

PET imaging for thyroid cancers: Current status and future directions

Positron emission tomography–computed tomography (PET/CT) combines both functional and anatomic information and provides in vivo molecular information on biological processes that can be useful at different steps of evolution of thyroid cancers. ¹⁸Fluorodeoxyglucose being highly trapped in rapidly dividing cells makes ¹⁸F-FDG-PET recommended in the staging, prognostic evaluation and follow-up of metastatic and/or of poorly differentiated thyroid carcinomas. ¹⁸F-FDG PET/CT can help in the localization of persistent/recurrent disease. However, its sensitivity depends widely on tumor burden and histology. Iodine 124 (¹²⁴I) is currently under evaluation for diagnosis and pretherapeutic dosimetry planning. PET/CT using ¹⁸F-FDOPA is the most sensitive radiopharmaceutical for localizing persistent/recurrent medullary thyroid carcinoma (MTC). However, its sensitivity depends on calcitonin levels, with a threshold value of around 150 pg/mL. ¹⁸F-FDG PET/CT can also be used in MTC with short calcitonin or CEA doubling time.     

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. Am. J. Hematol. 90:975–980, 2015. © 2015 Wiley Periodicals, Inc.     

The Value of 18F-FDG PET/CT Imaging Combined With Pretherapeutic Ki67 for Early Prediction of Pathologic Response After Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer

To evaluate the value of ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and pretherapeutic Ki67 in predicting pathologic response in locally advanced breast cancer (LABC) after neoadjuvant chemotherapy (NAC).As a training set, total 301 LABC patients treated with NAC were retrospectively analyzed to evaluate the potential predictive value of pretherapeutic Ki67 for pathologic complete response (pCR) after NAC. Another 60 LABC patients were prospectively included as a validation set to evaluate the value of Ki67 combined PET/CT as pCR predictors. Ki67 was assessed in pretherapy core needle biopsy specimens and PET/CT scans were performed at baseline (before initiating NAC), after the 2nd, and 4th cycle of NAC. Maximum standardized uptake value (SUVmax) and its changes relative to baseline (ΔSUVmax%) were used as parameters of PEC/CT.In the training set, Ki67 was a predictor of pCR to NAC, with area under the curve (AUC) of 0.624 (P = 0.003) in receiver-operating characteristic (ROC) analysis. In the validation set, Ki67 alone did not show significant value in predicting pCR in the validation set. ΔSUVmax% after then 2nd or 4th course are predictors of pCR to NAC with the AUC of 0.774 (P = 0.002) and 0.791 (P = 0.002), respectively. When combined with ΔSUVmax% after the 2nd and 4th course NAC, Ki67 increased the value of ΔSUVmax% in predicting pCR with the AUC of 0.824 (P = 0.001). Baseline SUVmax and after 2nd, 4th course NAC had no predictive value for pCR, but SUVmax after the 2nd and 4th course showed remarkable predictive value for nonpathologic response (Grade 1 in Miller-Payne Grading System) with the AUC of 0.898 (P = 0.0001) and 0.801 (P = 0.003).Both PET/CT and Ki67 can predict pCR to NAC in LABC patients in the early phases of treatment. PET/CT combined Ki67 is a better pCR predictor for response to NAC. This helps the physician to predict the probability of pCR, and facilitates the optimization of individual treatment plan in case of ineffective and/or excessive chemotherapy.     

The role of 18FDG PET/CT in the management of colorectal liver metastases

Introduction

Surgical resection remains the only potentially curative treatment for colorectal liver metastases (CLM). However, involvement of both the hepatic lobes or extrahepatic disease (EHD) can be a contra-indication for resection. The aim of the present study was to examine the addition of combined positron emission and computed tomography (PET/CT) to CLM staging to assess the effects upon staging and management.

Methods

All CLM patients referred to a single centre between January 2005 and January 2009 were prospectively included. All underwent routine staging (clinical examination and computed tomography), followed by a whole body ¹⁸fluoro-deoxy-glucose (¹⁸FDG)-PET/CT scan and Fong clinical risk score calculation.

Results

Sixty-four patients were included [63% male with a median age of 63 years (age range 32–79 years)]. The addition of PET/CT led to disease upstaging in 20 patients (31%) and downstaging in two patients (3%). EHD was found in 24% of low-risk patients (Fong score 0–2) as compared with 44% of high-risk patients (Fong score 3–5) (P = 0.133). There was a trend towards a greater influence upon management in patients with a low score (44% vs. 17%; P = 0.080).

Conclusion

The addition of PET/CT led to management changes in over one-third of patients but there was no correlation between alterations in staging or management and the Fong clinical risk score; suggesting that PET/CT should be utilized, where available, in the pre-operative staging of CLM patients.     

PET/CT evaluation of response to chemotherapy in non-small cell lung cancer: PET response criteria in solid tumors (PERCIST) versus response evaluation criteria in solid tumors (RECIST)

Background

¹⁸F-FDG PET/CT is increasingly used in evaluation of treatment response for patients with non-small cell lung cancer (NSCLC). There is a need for an accurate criterion to evaluate the effect and predict the prognosis. The aim of this study is to evaluate therapeutic response in NSCLC with comparing PET response criteria in solid tumors (PERCIST) to response evaluation criteria in solid tumors (RECIST) criteria on PET/CT.

Methods

Forty-four NSCLC patients who received chemotherapy but no surgery were studied. Chemotherapeutic responses were evaluated using ¹⁸F-FDG PET and CT according to the RECIST and PERCIST methodologies. PET/CT scans were obtained before chemotherapy and after 2 or 4-6 cycles’ chemotherapy. The percentage changes of tumor longest diameters and standardized uptake value (SUV) (corrected for lean body mass, SUL) before and after treatment were compared using paired t-test. The response was categorized into 4 levels according to RECIST and PERCIST: CR (CMR) =1, PR (PMR) =2, SD (SMD) =3, PD (PMD) =4. Pearson chi-square test was used to compare the proportion of four levels in RECIST and PERCIST. Finally the relationship between progression-free survival (PFS) and clinicopathologic parameters (such as TNM staging, percentage changes in diameters and SUL, RECIST and PERCIST results etc.) were evaluated using univariate and multivariate Cox proportional hazards regression method.

Results

The difference of percentage changes between diameters and SUL was not significant using paired t-test (t=–1.69, P=0.098). However the difference was statistically significant in the 40 cases without increasing SUL (t=–3.31, P=0.002). The difference of evaluation results between RECIST and PERCIST was not significant by chi-square test (χ²=5.008, P=0.171). If RECIST evaluation excluded the new lesions which could not be found or identified on CT images the difference between RECIST and PERCIST was significant (χ²=11.759, P=0.007). Reduction rate of SUL_peak (%), RECIST and PERCIST results were significant factors in univariate Cox analysis. But Multivariate Cox proportional hazards regression analysis demonstrated that only PERCIST was a significant factor for predicting DFS [hazard ratio (HR), 3.20; 95% (CI), 1.85-5.54; P<0.001].

Conclusions

PERCIST and RECIST criteria have good consistency and PERCIST (or PET) is more sensitive in detecting complete remission (CR) and progression. PERCIST might be the significant predictor of outcomes. The combination of PERCIST and RECIST would provide clinicians more accurate information of therapeutic response in earlier stage of treatment.