High Maximum Standardized Uptake Value Research Articles

Prospective Comparison of [18F]FDG and [18F]AIF-FAPI-74 PET/CT in the Evaluation of Potentially Resectable Pancreatic Ductal Adenocarcinoma.

Accurate clinical staging of potentially resectable pancreatic ductal adenocarcinoma (PDAC) is critical for establishing optimal treatment strategies. While the efficacy of fluorine-18-fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) in clinical staging is unclear, PET/CT detecting fibroblast-activation protein (FAP) expression has recently received considerable attention for detecting various tumors, including PDAC, with high sensitivity. We explored the efficacy of [18F]FDG and [18F]AIF-FAPI-74 PET/CT in the initial evaluation of potentially resectable PDAC. Between 2021 and 2022, twenty participants with newly diagnosed potentially resectable PDAC were enrolled. After the initial evaluation with pancreatic CT, [18F]FDG PET/CT, and [18F]AIF-FAPI-74 PET/CT, treatment strategies were determined considering the participant's general status, clinical staging, and resectability. Pathological information from the surgical specimens was only available in 17 participants who underwent curative-intent surgery. Head-to-head comparisons of quantitative radiotracer uptake and diagnostic performance were performed among imaging modalities. [18F]AIF-FAPI-74 PET/CT showed a significantly higher maximum standardized uptake value than [18F]FDG PET/CT did in evaluating primary pancreatic lesions (median [interquartile range]; 12.6 [10.7-13.7] vs. 6.3 [4.8-9.2]; P < 0.001). In contrast, [18F]AIF-FAPI-74 PET/CT showed a significantly lower mean standardized uptake value than [18F]FDG PET/CT did in evaluating background organ (median [interquartile range]) 0.8 [0.7-0.9] vs. 2.6 [2.3-2.7]; P < 0.001). In addition, the sensitivity of [18F]AIF-FAPI-74 PET/CT in detecting metastatic lymph nodes was higher than that of [18F]FDG PET/CT (50.0% vs. 0.0%; P = 0.026). This study demonstrated that [18F]AIF-FAPI-74 PET/CT could improve the clinical staging of potentially resectable PDAC.

Surgical indication and management of obstructive colonic metastasis from primary lung adenocarcinoma: report of a case and review of the literature

BackgroundColonic metastasis from lung cancer is very rare and is typically associated with poor prognosis. Herein, we report the case of a patient who achieved intermediate-term survival using a multimodal treatment approach, including chemotherapy, immunotherapy, radiotherapy, and surgical resection for obstructive colonic metastasis from primary lung adenocarcinoma.Case presentationA woman in her 50s presented with anemia and a positive fecal occult blood test. Computed tomography revealed a tumor in the right upper lobe of the lung with mediastinal lymphadenopathy and wall thickening in the transverse colon. Colonoscopy revealed a stricture involving 50% of the colonic lumen. Biopsy revealed a poorly differentiated adenocarcinoma positive for CK-7 and TTF-1, very focally positive for napsin A, and negative for CK-20 and CDX-2. Furthermore, positron emission tomography/CT (PET/CT) showed a high maximum standardized uptake value (SUVmax) of 8.2 in the iliac bone. Based on these findings, the patient was diagnosed with primary lung adenocarcinoma with simultaneous metastasis to the transverse colon and iliac bone (cT4N3M1c, cStage IVB).After receiving first-line chemotherapy with atezolizumab, pemetrexed, and carboplatin, the tumors shrank after 4 courses. Subsequently, the patient received maintenance therapy with atezolizumab and pemetrexed. However, the tumor enlarged after 10 courses. Second-line chemotherapy with docetaxel and ramucirumab (3 courses) failed to achieve tumor reduction. Colonoscopy revealed an impassable colonic tumor. Nineteen months after diagnosis, surgery was planned for imminent intestinal obstruction.We determined that the colonic tumor was resectable, because laparoscopic exploration revealed no other metastases. The tumor was resected by partial colectomy with ileocolonic anastomosis. The postoperative course was uneventful. Pathological examination revealed a resection margin that was negative for malignancy, and the histological type was consistent with metastatic lung adenocarcinoma.The patient then received nab-paclitaxel therapy; however, she developed symptoms of superior vena cava syndrome after 3 courses. The patient received palliative irradiation (30 Gy/10 fr) followed by nivolumab. She soon developed a solitary brain metastasis, and stereotactic irradiation was planned. After 3 courses of nivolumab, the metastasis was reduced significantly, and stereotactic brain irradiation was canceled. The lung tumor and mediastinal lymphadenopathy gradually shrank, and the patient survived for 13 months after surgery without disease progression.ConclusionsIn this case, surgical resection of colonic metastasis from primary lung adenocarcinoma may have contributed to the short-term prognosis as a bridge-to-next available multimodal treatment.

Association of serum lactate dehydrogenase with prognosis and tumor metabolism in patients with hepatocellular carcinoma treated with atezolizumab plus bevacizumab therapy.

Treatment outcomes are predicted by analyzing peripheral blood markers such as serum lactate dehydrogenase (LDH). We conducted this study to investigate whether serum LDH levels can predict the prognosis of patients treated with atezolizumab plus bevacizumab (ATZ/BEV) therapy for hepatocellular carcinoma (HCC) and whether LDH levels correlate with metabolic changes. We enrolled 66 HCC patients treated with ATZ/BEV. Based on the change in serum LDH levels before and after treatment, the patients were divided into two groups, and the prognosis of each group was examined. Moreover, the association of LDH levels with tumor metabolism was analyzed by fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). There were 32 patients categorized as the LDH-decrease group. Kaplan-Meier survival analysis indicated worse progression-free survival (PFS) in the LDH-increase group than in the LDH-decrease group (p = 0.0029). Multivariate analysis showed that an increase in the LDH level was an independent risk factor for worse PFS (p = 0.0045). The baseline LDH level correlated significantly with a high maximum standardized uptake value of 18F-FDG, according to the PET/CT findings. Transcriptomic analyses of specimens resected after ATZ/BEV therapy showed downregulated mitochondria-related pathways. Serum LDH levels are a potential prognostic marker and an indicator of tumor metabolism.

Comparison of digital and analog [68Ga]Ga-PSMA-11 PET/CT for detecting post-prostatectomy biochemical recurrence in prostate cancer patients: a prospective study

Digital positron emission tomography/computed tomography (PET/CT) has shown enhanced sensitivity and spatial resolution compared with analog PET/CT. The present study compared the diagnostic performance of digital and analog PET/CT with [68Ga]Ga-PSMA-11 in prostate cancer patients who experienced biochemical recurrence (BCR) after prostatectomy. Forty prostate cancer patients who experienced BCR, defined as serum prostate-specific antigen (PSA) concentrations exceeding 0.2 ng/mL after prostatectomy, were prospectively recruited. These patients were stratified into three groups based on their serum PSA levels. [68Ga]Ga-PSMA-11 was injected into each patient, and images were acquired using both analog and digital PET/CT scanners. Analog and digital PET/CT showed comparable lesion detection rate (71.8% vs. 74.4%), sensitivity (85.0% vs. 90.0%), and positive predictive value (PPV, 100.0% vs. 100.0%). However, digital PET/CT detected more lesions (139 vs. 111) and had higher maximum standardized uptake values (SUVmax, 14.3 vs. 10.3) and higher kappa index (0.657 vs. 0.502) than analog PET/CT, regardless of serum PSA levels. On both analog and digital PET/CT, lesion detection rates and interrater agreement increased with increasing serum PSA levels. Compared with analog PET/CT, digital PET/CT detected more lesions with a higher SUVmax and better interrater agreement in prostate cancer patients who experienced BCR after prostatectomy.

Long-term outcomes and risk factors for recurrence after lung segmentectomy.

The long-term oncological outcomes and risk factors for recurrence after lung segmentectomy are unclear. The aims of this study were to investigate the long-term prognosis and to evaluate risk factors for recurrence after segmentectomy. Between January 2008 and December 2012, a total of 177 patients underwent segmentectomy for clinical stage I non-small cell lung cancer. The median follow-up period was 120.1 months. The overall survival (OS) and recurrence-free survival curves were analysed using the Kaplan-Meier method with a log-rank test. Univariable and multivariable analyses were used to identify significant factors that predicted recurrence. The study included 177 patients with a median age of 67 years. The median operative time was 155 min. No 30-day deaths were observed. Nine patients (5.1%) had recurrences: loco-regional in 3, distant in 3 and both in 3. The 5-year and 10-year recurrence-free survival rates were 89.7% and 79.8%, and the OS rates were 90.9% and 80.4%, respectively. On multivariable analysis, the risk factor associated with recurrence was a pure solid tumour [hazard ratio, 23.151; 95% confidence interval 2.575-208.178; P = 0.005]. The non-pure solid tumour group had a significantly better probability of survival (5-year OS: 95.4% vs 77.2%; 10-year OS: 86.5% vs 61.8%; P < 0.0001). A total of 113 patients received preoperative positron emission tomography/computed tomography. Patients with a higher maximum standardized uptake value had a significantly higher recurrence rate. Segmentectomy for clinical stage I non-small cell lung cancer produced acceptable long-term outcomes. Pure solid radiographic appearance was associated with recurrence and decreased survival.

Oncologic outcomes after minimally invasive segmentectomy or lobectomy in patients with hypermetabolic clinical stage IA1-2 non–small cell lung cancer

ObjectiveTo evaluate the oncologic outcome of patients with hypermetabolic tumors resected by segmentectomy or lobectomy. MethodsThis was a retrospective analysis of all consecutive patients with peripheral clinical stage IA1-2 non–small cell lung cancer (January 2017-June 2023) who underwent resection by segmentectomy or lobectomy in a single center. A hypermetabolic tumor was defined as a tumor with a positron emission tomography (PET) maximum standardized uptake value >2.5. Propensity score case-matching analysis was used to generate 2 balanced groups of patients with hypermetabolic tumors operated by segmentectomy or lobectomy. Four-year overall survival (OS), event-free survival (EFS), and cancer-specific survival were compared between the matched groups. ResultsA total of 164 segmentectomies and 234 lobectomies were analyzed. There were 91 (55%) hypermetabolic tumors in the segmentectomy group versus 178 in the lobectomy group (76%), P < .001. The comparison of the matched groups with hypermetabolic tumors showed a better 4-year OS after lobectomy compared with segmentectomy (lobectomy 87%; 95% confidence interval [CI], 76-93; segmentectomy, 67%; 95% CI, 49-80; P = .029). The 4-year EFS appeared to have a better trend after lobectomy (77%; 95% CI, 65-85) compared with segmentectomy (58%; 95% CI, 39-72), P = .088. The 4-year cancer-specific survival, however, was similar between the matched groups (lobectomy, 95%; 95% CI, 86-98 vs segmentectomy, 94%; 95% CI, 78-99, P = .79). ConclusionsEarly-stage peripheral hypermetabolic tumors are associated with poorer oncologic outcomes compared with less PET-avid tumors. Despite poorer OS and EFS after segmentectomy likely caused by cancer-unrelated deaths, cancer-specific survival in this high-risk group was similar after lobectomy or segmentectomy. In well-selected patients, a high PET maximum standardized uptake value should not be considered a contraindication to segmentectomy.

Radiologic Parameters Predicting the Histologic Invasiveness of Pure Ground-Glass Nodules

BackgroundThis study aimed to investigate the diagnostic performance of combined computed tomography (CT) and fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for predicting histologic invasiveness of pure ground-glass nodules (pGGNs). MethodsThe study analyzed 91 patients who underwent resection of pGGNs and examined the correlation of pathologic invasiveness with preoperative CT and FDG PET findings. ResultsOverall, 24, 36, and 31 patients had adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IAD), respectively. Compared with AIS and MIA, IAD was significantly correlated with larger CT size (P = .001), maximum CT value (P = .026), and high maximum standardized uptake value (SUVmax; P < .001). Multivariable logistic analyses revealed that CT size (odds ratio [OR], 3.848; P = .019) and SUVmax (OR, 4.968; P = .009) were independent predictors of histologic invasiveness. Receiver operating characteristic curve analysis revealed that a cutoff CT size value of 18 mm predicted histologic invasiveness with a sensitivity and specificity of 65% and 80%, respectively; similarly, a cutoff SUVmax value of 1.5 predicted histologic invasiveness with a sensitivity and specificity of 61% and 90%, respectively. Of 20 lesions with CT size ≥18 mm and SUVmax ≥1.5, 16 (80%) were IAD. Of 54 lesions with CT size <18 mm and SUVmax <1.5, 46 (85%) were non-IAD lesions. Furthermore, all pGGNs with SUVmax ≥2.5 were IAD. ConclusionsCT size and SUVmax were significantly correlated with the histologic invasiveness of pGGNs. These factors may aid in determining optimal surgical procedures.

18 F-FDG PET/CT characteristics of IASLC grade 3 invasive adenocarcinoma and the value of 18 F-FDG PET/CT for preoperative prediction: a new prognostication model.

This study is performed to investigate the imaging characteristics of the International Association for the Study of Lung Cancer grade 3 invasive adenocarcinoma (IAC) on PET/CT and the value of PET/CT for preoperative predicting this tumor. We retrospectively enrolled patients with IAC from August 2015 to September 2022. The clinical characteristics, serum tumor markers, and PET/CT features were analyzed. T test, Mann-Whitney U test, χ 2 test, Logistic regression analysis, and receiver operating characteristic analysis were used to predict grade 3 tumor and evaluate the prediction effectiveness. Grade 3 tumors had a significantly higher maximum standardized uptake value (SUV max ) and consolidation-tumor-ratio (CTR) ( P < 0.001), while Grade 1 - 2 tumors were prone to present with air bronchogram sign or vacuole sign ( P < 0.001). A stepwise logistic regression analysis revealed that smoking history, CEA, SUV max , air bronchogram sign or vacuole sign and CTR were useful predictors for Grade 3 tumors. The established prediction model based on the above 5 parameters generated a high AUC (0.869) and negative predictive value (0.919), respectively. Our study demonstrates that grade 3 IAC has a unique PET/CT imaging feature. The prognostication model established with smoking history, CEA, SUV max , air bronchogram sign or vacuole sign and CTR can effectively predict grade 3 tumors before the operation.

Clinical T2 N0 M0 Esophageal Cancer: Identifying Predictive Factors of Upstaging

BackgroundInaccuracy of clinical staging renders management of clinical T2 N0 M0 (cT2 N0 M0) esophageal cancer difficult. When an underlying advanced-stage disease is understaged to cT2 N0 M0, patients miss the opportunity to gain the potential benefits of neoadjuvant therapy. This study aimed to identify preoperative factors that predict underlying advanced-stage esophageal cancer. MethodsFrom 2000 to 2020, 1579 patients with esophageal cancer underwent esophagectomy. Sixty patients who underwent upfront surgery for cT2 N0 M0 esophageal cancer were included in this study. The median age was 62.5 years, and 78% (n = 47) of these patients were male. Radiologic, clinical, and endoscopic factors were evaluated as preoperative markers. The Fisher exact and the Wilcoxon rank sum tests were used for categoric and continuous variables, respectively. Random forest classification was used to identify preoperative factors for predicting upstaging and downstaging. ResultsOf the 60 patients, 8 (13%) were found to have pathologic T2 N0 M0 esophageal cancer. Sixteen (27%) patients had cancer that was pathologically downstaged, and 36 (60%) had upstaged disease. Seven (19%) patients had upstaged cancer on the basis of the pathologic T stage, 14 (39%) had upstaging on the basis of the pathologic N stage, and 15 (42%) had upstaging on the basis of both T and N stages. Dysphagia (P = .003) and tumor maximum standardized uptake value (P = .048) were predictors of upstaging, with a combined predictive value of up to 75%. ConclusionsThe presence of dysphagia and of high maximum standardized uptake value (≥5) of the tumor is predictive of more advanced underlying disease for patients with cT2 N0 M0 esophageal cancer, and these patients should be considered for neoadjuvant therapy.

Development and Validation of a Machine-Learning Model to Predict POD24 Risk of Follicular Lymphoma

Background: Disease progression or relapse within 24 months after starting treatment (POD24) has been considered as an independent unfavorable factor in follicular lymphoma (FL). This study was to explore the discriminative accuracy of a machine learning-based (ML) model within different ethnic groups for identifying FL1-3a patients at higher risk for POD24. Methods: 1938 FL1-3a patients were enrolled from a Chinese multicenter cohort and randomly subdivided into a training cohort and an internal validation cohort. An external validation cohort included 1145 patients from the GALLIUM Study within different ethnicity. Univariable regression analysis with backward selection for inclusion of predictor variables and nonlinear analysis based on the XGBoost algorithm were used to develop a ML model for predicting POD24. For internal and external validation, the time-dependent area under the receiver operating characteristic curve (AUROC) was used to investigate the model's predictive performance, compared with established traditional models such as Follicular Lymphoma International Prognostic Index (FLIPI), FLIPI-2 and PRIMA-PI. The calibration and clinical usefulness of the ML model were evaluated using calibration plots and decision curve analyses, respectively. Results: During the follow-up period, 383 (19.7%) and 405 (36.3%) of patients who experienced POD24 were identified in the Chinese cohort and the GALLIUM Study, respectively. In the training cohort, important features of POD24 based on the XGBoost algorithm were ranked by SHAP analysis. Increased lymphocyte-to-monocyte ratio (LMR&amp;gt;10) ranked first (scoring 2), followed by elevated lactate dehydrogenase (LDH), hemogolobin reduction (HGB&amp;lt;12g/dl), elevated beta-2 microglobulin (B2-MG), higher maximum standardized uptake value (SUVmax&amp;gt;10), and 4 or more involved lymph nodes (each scoring 1) were incorporated into the new ML model, referred to as FLIPI-C. The new model performed well in predicting PFS as well as OS, and stratified patients into low- (0-3) and high-risk groups (4-7). In internal validation, FLIPI-C demonstrated a higher AUROC of 0.764 (95%CI:0.721-0.806) for POD24 prediction compared with 0.648 (95%CI: 0.599-0.696) of FLIPI, 0.706 (95%CI: 0.658-0.754) of FLIPI-2 and 0.716 (95%CI: 0.669-0.763) of PRIMA-PI. In external validation with GALLIUM Study, FLIPI-C demonstrated a higher AUROC of 0.701 (95%CI: 0.659-0.741) for POD24 prediction compared with 0.578 (95%CI: 0.531-0.625) of FLIPI, 0.600 (95%CI: 0.554-0.645) of FLIPI-2 and 0.593 (95%CI: 0.547-0.639) of PRIMA-PI. In addtion, the FLIPI-C model had adequate calibration with similar predicted and observed risk of POD24. In decision curve analysis, FLIPI-C yielded improved net benefits compared with FLIPI, FLIPI-2 and PRIMA-PI. Conclusions: TheFLIPI-C model generated using a machine learning approach exhibited greater discriminative accuracy than prior established traditional models for predicting POD24 and is valuable for treatment selection and prognostic assessment of FL.

Preoperative predictors of spread through air spaces in lung cancer

ObjectiveSpread through air spaces (STAS) is a new histologic feature of invasion of non–small cell lung cancer that lacks sensitivity and specificity on frozen sections and is associated with higher recurrence and worse survival with sublobar resections. Our objective is to identify preoperative characteristics that are predictive of STAS to guide operative decisions. MethodsFrom January 2018 through December 2021, 439 cT1-3N0 M0 patients with non–small cell lung cancer and a median age of 68 years, 255 (58%) women, who underwent primary surgery at our institution were included. Patients who received neoadjuvant therapy and whose STAS status was not documented were excluded. Age, sex, smoking status, tumor size, ground-glass opacities, maximum standardized uptake values, and molecular markers on preoperative biopsy were evaluated as preoperative markers. Comparisons between groups were conducted using standardized mean differences and random forest classification was used for prediction modeling. ResultsOf the 439 patients, 177 had at least 1 STAS-positive tumor, and 262 had no STAS-positive tumors. Overall, 179 STAS tumors and 293 non-STAS tumors were evaluated. Younger age (50 years or younger), solid tumor, size ≥2 cm, and maximum standardized uptake value ≥2.5 were independently predictive of STAS with prediction probabilities of 50%, 40%, 38%, and 40%, respectively. STAS tumors were more likely to harbor KRAS mutations and be PD-L1 negative. ConclusionsYoung age (50 years or younger), larger (≥2 cm) solid tumors, high maximum standardized uptake values, and presence of KRAS mutation, are risk factors for STAS and can be considered for lobectomy. Smoking status and gender are still controversial risk factors for STAS.

18F-FDG PET/CT in evaluation of squamous cell carcinoma.

Squamous cell carcinomas (SCC) are a number of different types of cancer that result from squamous cells. These cells form on the surface of the skin, on the lining of the respiratory and digestive tracts etc. To evaluate SCC and frequencies of their localizations based on the findings of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). This study included 343 consecutive patients with SCC who were sent for the 18F-FDG PET/CT. Inclusion criteria were: Pathohistologically verified SCC; absence of malignancy of any other localization, as well as absence of infection; and glycemia ≤11mmol/L. The pathological findings on 18F-FDG PET/CT were present in 86% of patients. There was statistically significant difference in the finding of 18F-FDG PET/CT in relation to gender (P>0.006). The disease was more often present in women. The most common localizations of disease were: lungs (70%), vagina/cervix (18%), gastrointestinal tract (18%), head and neck (5%). Highest maximum standardized uptake value (SUVmax) levels were seen in the lungs 11.78±8.38, vagina/cervix 11.21±8.10, and head and neck area 6.32±3.96. Fluorine-18-FDG PET/CT can be informative in evaluation of SCC. Disease is present usually in women, although it is the same pathohistological type of disease, different organs accumulate this radioactive contrast differently.

Methionine-PET to differentiate between brain lesions appearing similar on conventional CT/MRI scans.

11 C-Methionine (MET)-PET is a useful tool in neuro-oncology. This study aimed to examine whether a combination of diagnostic variables associated with MET uptake could help distinguish between brain lesions that are often difficult to discriminate in conventional CT and MRI. MET-PET was assessed in 129 patients with glioblastoma multiforme, primary central nervous lymphoma, metastatic brain tumor, tumefactive multiple sclerosis, or radiation necrosis. The accuracy of the differential diagnosis was analyzed using five diagnostic characteristics in combination: higher maximum standardized uptake value (SUV) of MET in the lesion/the mean normal cortical SUV of MET ratio, overextension beyond gadolinium, peripheral pattern indicating abundant MET accumulation in the peripheral region, central pattern denoting abundant MET accumulation in the central region, and dynamic-up suggesting increased MET accumulation during dynamic study. The analysis was conducted on sets of two of the five brain lesions. Significant differences in the five diagnostic traits were observed among the five brain lesions, and differential diagnosis could be achieved by combining these diagnostic features. The area under the curve between each set of two of the five brain lesions using MET-PET features ranged from .85 to 1.0. According to the findings, combining the five diagnostic criteria could help with the differential diagnosis of the five brain lesions. MET-PET is an auxiliary diagnostic technique that could help in distinguishing these five brain lesions.

Programmed death ligand-1 expression and occult lymph node metastasis in non-small cell lung cancer.

Identifying the preoperative risk factors for lymph node upstaging could contribute to the development of individualized perioperative treatment for patients with non-small cell lung cancer (NSCLC). The current study aimed to evaluate the risk factors for lymph node upstaging, including gene mutation and programmed death ligand-1 expression in patients with resectable NSCLC. Data on the clinicopathological characteristics of patients who underwent lobectomy for clinical N0 NSCLC at our institution were collected. The clinicopathological findings of the pathological N0 and lymph node upstaging groups were then analyzed. Univariate and multivariate analyses were performed to examine the predictive factors for nodal upstaging. Of 291 patients, 40 had postoperative nodal upstaging (n = 25, N1; n = 15, N2). Large tumor size and high maximum standardized uptake value were significantly associated with nodal upstaging. The nodal upstaging group had a higher proportion of patients with solid adenocarcinoma and lymphatic, vascular, and pleural invasion than the pathological N0 group. Further, the nodal upstaging group had a higher proportion of patients with positive programmed death ligand-1 expression than the pathological N0 group. Univariate and multivariate analyses showed that tumor size and positive programmed death ligand-1 expression were associated with nodal upstaging. The appropriate therapeutic strategy including preoperative treatment and resection should be cautiously considered preoperatively in patients with clinical N0 NSCLC who have large tumors and positive programmed death ligand-1 expression.

Prognostic role of preoperative fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography with an image-based harmonization technique: A multicenter retrospective study

ObjectivesDespite the prognostic impacts of preoperative fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography examination, fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography–based prognosis prediction has not been used clinically because of the disparity in data between institutions. By applying an image-based harmonized approach, we evaluated the prognostic roles of fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters in clinical stage I non–small cell lung cancer. MethodsWe retrospectively examined 495 patients with clinical stage I non–small cell lung cancer who underwent fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography examinations before pulmonary resection between 2013 and 2014 at 4 institutions. Three different harmonization techniques were applied, and an image-based harmonization, which showed the best-fit results, was used in the further analyses to evaluate the prognostic roles of fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters. ResultsCutoff values of image-based harmonized fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters, maximum standardized uptake, metabolic tumor volume, and total lesion glycolysis were determined using receiver operating characteristic curves that distinguish pathologic high invasiveness of tumors. Among these parameters, only the maximum standardized uptake was an independent prognostic factor in recurrence-free and overall survivals in univariate and multivariate analyses. High image-based maximum standardized uptake value was associated with squamous histology or lung adenocarcinomas with higher pathologic grades. In subgroup analyses defined by ground-glass opacity status and histology or by clinical stages, the prognostic impact of image-based maximum standardized uptake value was always the highest compared with other fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography parameters. ConclusionsThe image-based fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography harmonization was the best fit, and the image-based maximum standardized uptake was the most important prognostic marker in all patients and in subgroups defined by ground-glass opacity status and histology in surgically resected clinical stage I non–small cell lung cancers.

Comparison of Al 18F-NOTA-FAPI-04 and 18F-FDG in recurrent esophageal cancer after surgery.

Recently, radionuclide labelling fibroblast activating protein inhibitors (FAPI) is regarded as the most promising imaging tracer forvarious tumours. Here we present the imaging finding of aluminium-[18F] fluoride (Al18F)-labelled 1,4,7-triazacyclononane-N,N',N"-triacetic acid (Al18F-NOTA-FAPI-04) and fluorine-18-fluorodeoxyglucose (18F-FDG) in postoperative recurrence esophageal cancer. The results presented that imaging with Al18F-NOTA-FAPI-04 showed significant improvement in detection of local recurrence and distant metastasis with higher maximum standardized uptake value (SUVmax) in the lesions compared with 18F-FDG.

Clinical Implications of FDG-PET in Pancreatic Ductal Adenocarcinoma Patients Treated with Neoadjuvant Therapy

PurposeTo evaluate the clinical significance of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with pancreatic ductal adenocarcinoma who underwent neoadjuvant therapy. MethodsAmong 285 consecutive patients who underwent pancreatic resection for pancreatic ductal adenocarcinoma between 2015 and 2021, 86 who underwent preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography after completion of neoadjuvant treatment were reviewed. Among preoperative factors, including post-treatment maximum standardized uptake value, predictors of early recurrence and poor prognosis were identified using multivariate analysis for decision making in surgery. ResultsNineteen (22%) patients with pancreatic ductal adenocarcinoma demonstrated high maximum standardized uptake (≥ 4.5). High post-treatment maximum standardized uptake (≥ 4.5) predicted early recurrence within 6 months after surgery and correlated with shorter recurrence-free survival. Elevated post-treatment CA19-9 level (> 37 U/ml) and maximum standardized uptake ≥ 4.5 were independent prognostic factors. Post-treatment, a high maximum standardized uptake value indicated a poorer prognosis than a low maximum standardized uptake value in both patients with elevated CA19-9 and normal CA19-9 levels. The median overall survival in patients with elevated post-treatment CA19-9 and high maximum standardized uptake was only 17 months; 67% experienced early recurrence. Dynamic changes in maximum standardized uptake during neoadjuvant therapy were correlated with pathological response to neoadjuvant therapy, but not with radiological response or change in CA19-9 level. ConclusionsPost-treatment assessment using maximum standardized uptake value is useful for stratifying patients with pancreatic ductal adenocarcinoma who will benefit from surgery. Instead of subsequent curative resection, additional neoadjuvant therapy should be considered in patients with a persistently high maximum standardized uptake value.

Qualitative and Quantitative Evaluation of Morpho-Metabolic Changes in Bone Cartilage Complex of Knee Joint in Osteoarthritis Using Simultaneous 18F-NaF PET/MRI-A Pilot Study.

Background Articular cartilage (AC) loss and deterioration, as well as bone remodeling, are all symptoms of osteoarthritis (OA). As a result, an ideal imaging technique for researching OA is required, which must be sensitive to both soft tissue and bone health. Objective The aim of this study was to assess the potential of simultaneous 18F sodium fluoride (18F-NaF) positron emission tomography/magnetic resonance imaging (PET/MRI) to identify as well as classify osseous metabolic abnormalities in knee OA and to see if degenerative changes in the cartilage and bone on MRI might be correlated with subchondral 18F-NaF uptake on PET. Methods Sixteen (32 knees) volunteers with no past history of knee injury, with or without pain, were enrolled for the research from January to July 2021. The images of both knees were taken utilizing an molecular magnetic resonance (mMR) body matrix coil on a simultaneous PET/MRI biograph mMR. The acquisition was conducted after 45 minutes of intravenous infusion of 18F-NaF 185-370 MBq (5-10 mCi) over one PET bed for 40 minutes, while MRI sequences were performed simultaneously. Results All pathologies showed significantly higher maximum standardized uptake value (SUV max ) than the background. Thirty-four subchondral magic spots were identified on 18F-NaF PET without any structural alteration on MRI. Bone marrow lesions (BMLs) and osteophytes with higher MRI osteoarthritis knee score (MOAKS) score showed higher 18F-NaF uptake (grade1˂grade2˂grade3). BMLs had corresponding AC degeneration. There was discordance between grade 1 osteophytes (86.6%), sclerosis (53.7%) and grade 1 BML in cruciate ligament insertion site (91.66%); they did not have high uptake of 18F-NaF. In case of cartilage, there was significant difference between AC grades and average subchondral SUV max and T2* relaxometry (grade0˂grade1˂grade2˂grade3˂grade4). BMLs are much more metabolically active than other pathologies, while sclerosis is the least. We also found that the subchondral uptake was statistically increased in the areas of pathology: Conclusion 18F-NaF PET/MRI was able to detect knee abnormalities unseen on MRI alone and simultaneously assessed metabolic and structural markers of knee OA across multiple tissues in the joint. Thus, it is a promising tool for detection of early metabolic changes in OA.

Metabolic reprogramming of cancer-associated fibroblasts in pancreatic cancer contributes to the intratumor heterogeneity of PET-CT

Intratumor heterogeneity of positron emission tomography-computed tomography (PET-CT) is reflected by variable 18F-fluorodeoxyglucose (FDG) uptake. Increasing evidence has shown that neoplastic and non-neoplastic components can affect the total 18F-FDG uptake in tumors. Cancer-associated fibroblasts (CAFs) is considered as the main non-neoplastic components in tumor microenvironment (TME) of pancreatic cancer. Our study aims to explore the impact of metabolic changes in CAFs on heterogeneity of PET-CT. A total of 126 patients with pancreatic cancer underwent PET-CT and endoscopic ultrasound elastography (EUS-EG) before treatment. High maximum standardized uptake value (SUVmax) from the PET-CT was positively correlated with the EUS-derived strain ratio (SR) and indicated poor prognosis of patients. In addition, single-cell RNA analysis showed that CAV1 affected glycolytic activity and correlated with glycolytic enzyme expression in fibroblasts in pancreatic cancer. We also observed the negative correlation between CAV1 and glycolytic enzyme expression in the tumor stroma by using immunohistochemistry (IHC) assay in the SUVmax-high and SUVmax-low groups of pancreatic cancer patients. Additionally, CAFs with high glycolytic activity contributed to pancreatic cancer cell migration, and blocking CAF glycolysis reversed this process, suggesting that glycolytic CAFs promote malignant biological behavior in pancreatic cancer. In summary, our research demonstrated that the metabolic reprogramming of CAFs affects total 18F-FDG uptake in tumors. Thus, an increase in glycolytic CAFs with decreased CAV1 expression promotes tumor progression, and high SUVmax may be a marker for therapy targeting the neoplastic stroma. Further studies should clarify the underlying mechanisms.

Evaluation of FAPI PET imaging in gastric cancer: a systematic review and meta-analysis.

Purpose: Recent studies suggest that 68Ga-FAPI PET/CT demonstrated superiority over 18F-FDG PET/CT in the evaluation of various cancer types, especially in gastric cancer (GC). By comprehensively reviewing and analysing the differences between 68Ga-FAPI and 18F-FDG in GC, some evidence is provided to foster the broader clinical application of FAPI PET imaging. Methods: In this review, studies published up to July 3, 2023, that employed radionuclide labelled FAPI as a diagnostic radiotracer for PET in GC were analysed. These studies were sourced from both the PubMed and Web of Science databases. Our statistical analysis involved a bivariate meta-analysis of the diagnostic data and a meta-analysis of the quantitative metrics. These were performed using R language. Results: The meta-analysis included 14 studies, with 527 patients, of which 358 were diagnosed with GC. Overall, 68Ga-FAPI showed higher pooled sensitivity (0.84 [95% CI 0.67-0.94] vs. 0.46 [95% CI 0.32-0.60]), specificity (0.91 [95% CI 0.76-0.98] vs. 0.88 [95% CI 0.74-0.96]) and area under the curve (AUC) (0.92 [95% CI 0.77-0.98] vs. 0.52 [95% CI 0.38-0.86]) than 18F-FDG. The evidence showed superior pooled sensitivities of 68Ga-FAPI PET over 18F-FDG for primary tumours, local recurrence, lymph node metastases, distant metastases, and peritoneal metastases. Furthermore, 68Ga-FAPI PET provided higher maximum standardized uptake value (SUVmax) and tumour-to-background ratios (TBR). For bone metastases, while 68Ga-FAPI PET demonstrated slightly lower patient-based pooled sensitivity (0.93 vs. 1.00), it significantly outperformed 18F-FDG in the lesion-based analysis (0.95 vs. 0.65). However, SUVmax (mean difference [MD] 1.79 [95% CI -3.87-7.45]) and TBR (MD 5.01 [95% CI -0.78-10.80]) of bone metastases showed no significant difference between 68Ga-FAPI PET/CT and 18F-FDG PET/CT. Conclusion: Compared with 18F-FDG, 68Ga-FAPI PET imaging showed improved diagnostic accuracy in the evaluation of GC. It can be effectively applied to the early diagnosis, initial staging, and detection of recurrence/metastases of GC. 68Ga-FAPI may have the potential of replacing 18F-FDG in GC in future applications.