SUVmax Of Lymph Nodes Research Articles

Prognostic Value and Clinical Implication of Lymph Node-to-Primary Tumor SUV Ratio in Node-Positive Hypopharyngeal Squamous Cell Carcinoma Treated With Radiotherapy With or Without Chemotherapy.

The aim of this was to evaluate the prognostic significance of the nodal-to-primary tumor SUVmax ratio (NTR) in patients with node-positive hypopharyngeal squamous cell carcinoma (HPSCC) treated with radiotherapy with or without concurrent chemotherapy. The study aims to enhance prognostic accuracy by incorporating NTR into the American Joint Committee on Cancer (AJCC) staging system. This retrospective study included 191 patients with biopsy-proven node-positive HPSCC treated from 2005 to 2013. NTR was calculated as the ratio of SUVmax of metastatic lymph nodes to the primary tumor's SUVmax. Survival analyses were conducted using Cox regression models and Kaplan-Meier analysis. Receiver operating characteristic analysis compared the prognostic performance of the modified and AJCC staging systems. The median follow-up was 8.27 years, with 135 deaths (70.7%). High NTR (≥0.63) was significantly associated with worse overall survival (OS) and was an independent prognostic factor in multivariable analysis (adjusted hazards ratio [HR] = 1.63, P = 0.007). Median OS for high NTR was 17.4 months, compared with 75.2 months for low NTR. High NTR significantly predicted worse OS within AJCC stage IVA patients (HR = 6.09, P = 0.014). Patients in modified stage IVA (AJCC stage IVA with low NTR) had significantly longer OS than those in modified stage IVB (AJCC stage IVA with high NTR and AJCC stage IVB) (HR = 8.62, P = 0.003). The modified staging system incorporating NTR showed superior prognostic performance compared with the AJCC staging system. NTR is a significant independent prognostic factor for OS in node-positive HPSCC patients. Integrating NTR into the AJCC staging system improves prognostic accuracy.

Granzyme B PET/CT Imaging Evaluates Early Response to Immunotherapy in Gastric Cancer.

In several malignancies, only a limited number of patients respond to immune checkpoint inhibitors. Predicting and monitoring responses to these inhibitors represent an unmet clinical need. Here, we developed a PET/CT probe targeting granzyme B, [68Ga]Ga-NOTA-Gly-Gly-Gly-Ile-Glu-Pro-Asp-CHO (GSI), and aimed to investigate whether it can be used to monitor the effects of immune checkpoint inhibitors early in the course of therapy. Methods: Seventy-two patients with gastric cancer (stages III-IV) were recruited for [68Ga]Ga-DOTA-GSI PET/CT imaging after 2 or 3 cycles of the immunotherapy, and 40 patients were included in the final analysis. The SUVmax of primary tumors (SUVmax-t), SUVmax of metastatic lymph nodes (SUVmax-LN), and SUVmax of normal tissues (liver and blood pool) were measured, and their target-to-liver background ratio (TLR) and target-to-blood background ratio (TBR) were denoted for primary tumors as TLRtumor and TBRtumor and for metastatic lymph nodes as TLRLN and TBRLN, respectively. The treatment responses were assessed within 1 wk after full-course treatment according to RECIST version 1.1. Wilcoxon rank-sum tests were used to compare the PET/CT parameters between responders and nonresponders. Receiver operating characteristic curve analysis was used to assess the diagnostic efficacy of [68Ga]Ga-DOTA-GSI PET/CT parameters in identifying responders. Two-tailed P value of less than 0.05 was considered statistically significant. Results: We found that SUVmax-t, TLRtumor, TBRtumor, SUVmax-LN, and TBRLN were higher in responders than in nonresponders (2.49 ± 0.58 vs. 1.55 ± 0.48, P = 0.000; 2.24 ± 0.48 vs. 1.74 ± 0.67, P = 0.007; 1.38 ± 0.43 vs. 0.90 ± 0.23, P = 0.000; 2.24 ± 0.99 vs. 1.42 ± 0.55, P = 0.003; and 1.28 ± 0.68 vs. 0.83 ± 0.32, P = 0.012, respectively). According to receiver operating characteristic curve analysis, the area under the curve for SUVmax-t, TBRtumor, TLRtumor, SUVmax-LN, TLRLN, and TBRLN was 0.886, 0.866, 0.746, 0.772, 0.648, and 0.731, respectively. The threshold of SUVmax-t was 2.05, and its sensitivity and specificity were 81.0% and 84.2%, respectively. In addition, multivariate logistic regression indicated that TBRtumor was an independent predictor of treatment response (P = 0.03). Conclusion: Our results indicated that [68Ga]Ga-DOTA-GSI PET/CT is a promising tool for predicting early response to combined immunotherapy in gastric cancer patients.

The prognostic role of whole-body volumetric positron emission tomography/computed tomography parameters in treatment naive colorectal cancer patients with liver metastases.

The present study aimed to predict the prognostic role of quantitative 18F-fluorodeoxyglucose PET/computed tomography parameters such as maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) obtained from primary tumor, lymph node metastases, and liver metastasis (LM) in patients with colorectal LM (CLM). The research was designed as a retrospective study and 66 patients with CLM were enrolled between January 2017 and December 2018. Primary tumor SUVmax (PSUVmax), liver SUVmax (LSUVmax), and lymph node SUVmax (LnSUVmax) values obtained from the primary tumor, liver, and lymph nodes were recorded. In addition, total MTV (TMTV) and total TLG (TTLG) values were obtained by summing the values obtained from the primary tumor (PMTV and PTLG), lymph nodes (LnMTV and LnTLG), and liver (LMTV and LTLG). Univariate and multivariate Cox regression analysis was used to measure the effects of prognostic variables on mortality and survival. In univariate Cox regression analysis, PMTV (P = 0.001), LnMTV (P = 0.008), LnTLG (P = 0.008), LnSUVmax (P = 0.047), and TTLG (P = 0.038) were identified as prognostic factors for overall survival. No statistically significant relationship was found between MTV and TLG values of LM and overall survival. In multivariate analysis, PMTV (P = 0.022) was identified as an independent prognostic factor. In conclusion, our study demonstrated that the PMTV value used in evaluating treatment-naive patients diagnosed with CLM is an independent prognostic factor for survival. Our results need to be confirmed with more studies involving more patients.

Lymph nodes rather than pleural metabolic activity in 18F-FDG PET/CT correlates with malignant pleural effusion recurrence in advanced non-small cell lung cancer.

Frequently recurrent malignant pleural effusion (MPE) significantly hampers the life quality of advanced non-small cell lung cancer (NSCLC) patients. We aimed to explore the effects of progression patterns and local intervention on MPE recurrence and apply fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) to establish a predictive model for MPE recurrence in NSCLC. We retrospectively recruited two cohorts of patients including treatment-naïve NSCLC diagnosed with MPE at the onset and receiving PET/CT scanning, as well as those with MPE and undergoing first-line epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment. Pleural maximum standardized uptake value (SUVmax), metabolic tumor burden (MTV), total lesion glycolysis (TLG), and uptake patterns as well as SUVmax of lymph nodes (LN) were extracted. The primary outcome was MPE recurrence defined as re-accumulation of cytologically proven ipsilateral MPE. Step-wise multivariate Cox regression was used to identify candidate variables. Cox regression analysis and random survival forest were applied to establish models. A total of 148 treatment-naïve patients with EGFR-TKI treatment and MPE were recruited during the median follow-up period of 683 days, with 69 (46.6%) and 35 (23.6%) witnessing MPE recurrence at least once and twice. Intrapleural perfusion therapy at first recurrence was a protective factor for the second MPE recurrence (P=0.006), while intrapleural perfusion therapy at baseline could not benefit the first MPE recurrence (P=0.14). Conversely, prior systemic progression indicative of the change of systemic treatment was a protective factor for time to the first MPE recurrence (P<0.001); instead, the change of systemic treatment at the first MPE recurrence was not associated with second MPE recurrence (P=0.53). In another cohort with treatment-naïve NSCLC patients with MPE and PET/CT scanning, 103 patients regardless of the actionable mutation status were recruited during the median follow-up period of 304 days. Multivariate analysis suggested that the LN SUVmax >4.50 g/mL [hazard ratio (HR), 2.54; P=0.01], female gender (HR, 0.40; P=0.01), bone metastases (HR, 3.16; P=0.001), and systemic treatment (targeted therapy vs. chemotherapy: HR, 0.32; P=0.002; immunotherapy therapy vs. chemotherapy: HR, 0.99; P=0.97) could collectively indicate MPE recurrence with an optimal 300-day area under the curve (AUC) of 0.83. For patients with actionable mutation, LN SUVmax >4.50 g/mL (P=0.02) could forecast MPE recurrence independently. In summary, LN rather than pleural metabolic activity or uptake patterns could predict MPE recurrence for patients with or without targeted therapy. We should re-consider the application of intrapleural perfusion treatment for first-onset MPE and prompt it more at the moment of recurrent MPE. Promisingly, we could probably apply the non-invasive tool to identify the risk factors for MPE recurrence.

Comparative analysis of F-18 FDG PET/CT images between scrub typhus and systemic lupus erythematosus

This study evaluated the use of F-18 fluorodeoxyglucose (FDG) PET/CT imaging to differentiate between scrub typhus and systemic lupus erythematosus (SLE) in patients presenting with lymphadenopathy. We carried out a retrospective analysis of 18 scrub typhus patients and seven SLE patients, using various imaging parameters, including lymph node size, spleen and liver lengths, the distance between the two farthest lesions (Dmax), and assessments of glucose metabolism. On FDG PET images, we measured the maximum standardized uptake value (SUVmax) of the lymph nodes, spleen, and liver and the mean standardized uptake value (SUVmean) of the liver and spleen. The Dmax values of scrub typhus patients were significantly longer than those of SLE patients, indicating that lymphadenopathy is more generalized in the patients with scrub typhus. The SUVmax values for the lymph node, spleen, and liver were also higher in patients with scrub typhus, while the SUVmean of the liver and spleen did not differ between the two groups. This study is the first to compare FDG PET/CT images between these two conditions, suggesting the potential of this imaging modality to provide critical diagnostic distinctions.

Exploring the predictive potential of programmed death ligand 1 expression in healthy organs and lymph nodes as measured by 18F-BMS-986192 PET: pooled analysis of data from four solid tumor types

IntroductionImmune checkpoint inhibitors (ICIs) can elicit anticancer immune responses, but predictive biomarkers are needed. We measured programmed death ligand 1 (PD-L1) expression in organs and lymph nodes using 18F-BMS-986192 positron...

Comparison of an Affibody-based Molecular Probe and 18F-FDG for Detecting HER2-Positive Breast Cancer at PET/CT.

Background Human epidermal growth factor receptor 2 (HER2) affibody-based tracers could be an alternative to nonspecific radiotracers for noninvasive detection of HER2 expression in breast cancer lesions at PET/CT. Purpose To compare an affibody-based tracer, Al18F-NOTA-HER2-BCH, and fluorine 18 (18F) fluorodeoxyglucose (FDG) for detecting HER2-positive breast cancer lesions on PET/CT images. Materials and Methods In this prospective study conducted from June 2020 to July 2023, participants with HER2-positive breast cancer underwent both Al18F-NOTA-HER2-BCH and 18F-FDG PET/CT. HER2 positivity was confirmed with pathologic assessment (immunohistochemistry test results of 3+, or 2+ followed by fluorescence in situ hybridization, indicated HER2 amplification). Two independent readers visually assessed the uptake of tracers on images. Lesion uptake was quantified using the maximum standardized uptake value (SUVmax) and target to background ratio (TBR) and compared using a general linear mixed model. Results A total of 42 participants (mean age, 56.3 years ± 10.1 [SD]; 41 female) with HER2-positive breast cancer were included; 42 (100%) had tumors that were detected with Al18F-NOTA-HER2-BCH PET/CT and 40 (95.2%) had tumors detected with 18F-FDG PET/CT. Primary tumors in two of 21 participants, lymph node metastases in four of 21 participants, bone metastases in four of 15 participants, and liver metastases in three of nine participants were visualized only with Al18F-NOTA-HER2-BCH. Lung metastasis in one of nine participants was visualized only with 18F-FDG. Al18F-NOTA-HER2-BCH enabled depiction of more suspected HER2-positive primary tumors (26 vs 21) and lymph node (170 vs 130), bone (92 vs 66), and liver (55 vs 27) metastases than 18F-FDG. The SUVmax and TBR values of primary tumors and lymph node, bone, and liver metastases were all higher on Al18F-NOTA-HER2-BCH images than on 18F-FDG images (median SUVmax range, 10.4-13.5 vs 3.4-6.2; P value range, <.001 to .02; median TBR range, 2.7-17.6 vs 1.2-7.8; P value range, <.001 to .001). No evidence of differences in the SUVmax and TBR for chest wall or lung metastases was observed between Al18F-NOTA-HER2-BCH and 18F-FDG (P value range, .06 to .53). Conclusion PET/CT with the affibody-based tracer Al18F-NOTA-HER2-BCH enabled detection of more primary lesions and lymph node, bone, and liver metastases than PET/CT using 18F-FDG. ClinicalTrials.gov Identifier: NCT04547309 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Ulaner in this issue.

Different extramedullary disease shown in chemokine receptor 4 targeted PET/CT with [ 68 Ga]Ga-pentixafor in patients with Waldenström macroglobulinemia and smoldering disease.

It is important to distinguish Waldenström macroglobulinemia from smoldering Waldenström macroglobulinemia (sWM), because only patients with Waldenström macroglobulinemia require treatment, however the distinction can be clinically complex. The aim of this study is to investigate whether [ 68 Ga]Ga-pentixafor PET/CT shows different characteristics in sWM and Waldenström macroglobulinemia patients and therefore can help to differentiate Waldenström macroglobulinemia and sWM. Thirty-seven patients with newly diagnosed Waldenström macroglobulinemia and 11 sWM patients were analyzed [35 men and 13 women; 64.3 ± 10.7 (range, 29-87) years old]. The SUV max of bone marrow disease, lymph nodes, and other extramedullary diseases on [ 68 Ga]Ga-pentixafor were significantly higher than those on 2-[ 18 F]FDG PET/CT ( P < 0.05). On [ 68 Ga]Ga-pentixafor PET/CT, patients with Waldenström macroglobulinemia had more lymph node regions involved, significantly higher incidence of involvement in more than three lymph node regions, larger nodal disease, and higher incidence of other extramedullary disease when compared with sWM patients ( P < 0.05). Waldenström macroglobulinemia patients showed significantly higher total lesions uptake, total lesion volume, and SUV max of extramedullary disease than sWM patients did ( P < 0.05). None of the visual or semiquantitative indexes in 2-[ 18 F]FDG PET/CT showed significant difference between Waldenström macroglobulinemia and sWM patients. [ 68 Ga]Ga-pentixafor PET/CT had better diagnostic performance than 2-[ 18 F]FDG PET/CT in Waldenström macroglobulinemia. Patients with Waldenström macroglobulinemia presented with more extensive extramedullary disease shown in [ 68 Ga]Ga-pentixafor PET/CT than sWM patients did.

Abstract PO3-27-01: Prediction of pathological complete response to neoadjuvant treatment in loco-regional advancedbreast cancer by using advanced PET/CT metabolic parameters

Abstract Prediction of pathological complete response to neoadjuvant treatment in loco-regional advanced breast cancer by using advanced PET/CT metabolic parameters. Abstract: Background: The standard treatment for locally advanced breast cancer (LABC) is neoadjuvant systemic therapy followed by surgery. The usefulness of FDG PET/CT for evaluating the treatment efficacy in breast cancer is well established; however, the role of quantitative functional PET/CT parameters, such as the metabolic tumor volume (MTV) and total lesion glycolysis (TLG), remains inconclusive. The aim of this study was to determine the correlation between quantitative functional parameters derived from PET/CT in LABC patients at staging and the response to neoadjuvant therapy. Methods: Seventy-eight consecutive patients (aged 25-82 y) with confirmed LABC (stages II-III) who underwent PET/CT as a part of their staging assessment and received neoadjuvant therapy followed by surgery were retrospectively included in this study. All patients underwent an FDG PET/CT at staging; and values of SUV max, SUV mean, MTV, and TLG were determined from the PET/CT studies. The patients were divided into two groups, based on the completeness of histopathologic response to neoadjuvant therapy, both in the primary tumor and axillary lymph nodes. Clinical, imaging and demographic data were collected from patient’s medical record. Results: A complete pathologic response (pCR) was achieved in 33/78 (42%) patients. Among patients with ER/PR positive, Her2-neu negative tumors, in 23/27 (85%) patients only partial pathologic response was reached; 91% of patients with ER/PR negative, Her2-neu positive and 43% of Triple-negative patients had complete pathological? response. For the primary breast tumor response, a higher SUV max, 10.7±5.34 for pCR vs. 7.24±4.62 for non-pCR group was measured, p-value=0.003; threshold value of 6.625. A higher SUV mean in the primary tumor resulted in a significantly higher rate of pCR, 5.95±2.36 vs 4,4±2.16, p=0.004, with a threshold value of 5.795. Neither MTV, not TLG were predictive parameters of the primary tumor response. For lymph nodes response, SUV max and SUV mean had no role in the prediction of pCR. Statistically significant difference however, was found between pCR and non-pCR in MTV values in the involved lymph nodes, with a median =2.13 cm³ [0-7.85] in pCR group vs 5.43 cm³ [3.11-15.3] in non-pCR, p=0.01 (threshold value 2.375) as well as in TLG measurements, with a median of 4.64 [0-19.8] vs. 12.7 [3.21-23.1], p=0.047, (25-75 IQR). Conclusion: Primary breast tumor SUV max/mean values have a significant correlation with the treatment response and threshold values were found. Low MTV and TLG measurements in lymph nodes may predict pCR. Neither MTV nor TLG had were found to have a significant role in the prediction of the primary tumor response. Citation Format: Maisun Shamya, Olga Kagna, Zohar Keidar, Tala Palchan-Hazan, Salem Billan, Roxolyana Abdah-Bortnyak. Prediction of pathological complete response to neoadjuvant treatment in loco-regional advancedbreast cancer by using advanced PET/CT metabolic parameters [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-27-01.

When to Consider Invasive Lymph Node Staging in Non–Small-Cell Lung Cancer? A Novel Scoring System Utilising Metabolic Parameters in 18F-FDG PET/CT

ObjectiveThe maximum standardised uptake value (SUVmax) is a widely utilised metric in positron emission tomography/computed tomography for clinically staging non–small-cell lung cancer (NSCLC), yet the reliability of SUVmax remains controversial. We herein aimed to assess the effectiveness of semi-quantitative parameters, encompassing size, SUVmax, metabolic tumour volume (MTV), total lesion glycolysis (TLG) and heterogeneity factor (HF), in evaluating both primary tumours and lymph nodes (LNs) on positron emission tomography/computed tomography. A novel scoring system was devised to appraise the role of semi-quantitative parameters and visually evaluate LNs for nodal staging. Materials and MethodsPatients with pathological NSCLC, diagnosed between 2014 and 2019 and clinically staged I-III, were enrolled in the study. Patient demographics, including age, sex, tumour location, diameter, tumour-node-metastasis stage, as well as SUVmax, MTV, TLG and HF parameters of primary tumours and LNs, were documented. ResultsThe analysis comprised 319 patients and 963 LNs. Patients had a mean age of 61.62 years, with 91.5% being male. Adenocarcinoma exhibited a histological association with LN metastasis (P=0.043). The study findings revealed that tumour size, SUVmax, MTV, TLG and HF did not significantly affect the detection of LN metastasis. Conversely, non-squamous cell carcinoma, LNs exhibiting higher FDG levels than the liver, LN size, SUVmax, MTV and TLG were identified as risk factors (P<0.0001). The identified cut-off values were 1.05cm for LN size, 4.055 for SUVmax, 1.805cm3 for MTV and 5.485 for TLG. The scoring system incorporated these parameters, and visual assessment indicated that a score of ≥3 increased the risk of metastasis by 14.33 times. ConclusionWe devised a novel scoring system and demonstrated that LNs with a score of ≥3 in patients with NSCLC have a high likelihood of metastasis. This innovative scoring system can serve as a valuable tool to mitigate excessive and extreme measures in the assessment of invasive pathological staging.

Predictive value of metabolism and its heterogeneity parameters measured by preoperative 18 F-FDG PET/CT for mediastinal occult lymph node metastasis in cN0 lung invasive adenocarcinoma.

To explore the potential of intratumoral metabolism and its heterogeneous parameters, as measured by preoperative fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) imaging, to predict mediastinal occult lymph node metastasis in cN0 lung invasive adenocarcinoma. Seventy five patients were consecutively enrolled from January 2018 to December 2022. All patients underwent 18F-FDG PET/CT scans within two weeks before surgery, and had mediastinal lymph node metastasis confirmed by pathologic diagnosis after surgery. Metabolic parameters including the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), maximum average SUV (SUVpeak), tumor metabolic volume (MTV), and metabolic heterogeneity (HF) were measured. The relationship between primary focal metabolism, its heterogeneity parameters, and occult mediastinal lymph node metastasis was analyzed using an independent-sample t-test, analysis of covariance, and Mann-Whitney U test. A multivariate logistic regression model was used to analyze independent risk factors for mediastinal lymph node metastasis, while the receiver operating characteristic (ROC) curve assessed the predictive value of metabolic heterogeneity parameters for mediastinal occult lymph node metastasis. A total of 20 out of 75 patients (26.7%) were pathologically confirmed to have mediastinal lymph node metastasis. Analysis of covariance showed that the SUVmax, SUVmean, SUVpeak and MTV were significantly higher in patients with metastasis than in those without (all P<0.05). The metabolic heterogeneity parameters HF2 and HF3 were significantly higher in patients with mediastinal lymph node metastasis than in those without (P=0.013, 0.001), but not HF1. Multivariate Logistic regression analysis identified that tumor size, SUVmax, SUVpeak, lymph node SUVmax, and HF2 of the primary tumor as independent risk factors for mediastinal lymph node metastasis. Metabolic heterogeneity 3 demonstrated high predictive value for mediastinal occult lymph node metastasis (AUC=0.720, P=0.004). Metabolism and heterogeneity, as measured by preoperative 18F-FDG PET/CT in lung invasive adenocarcinoma, potentially have clinical value for predicting mediastinal occult lymph node metastasis.

Tumor and metastatic lymph nodes metabolic activity on 18F-FDG-PET/CT to predict progression-free survival in locally advanced cervical cancer.

The present study investigated the predictive diseases progression value of preoperative fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with local advanced cervical cancer (LACC). In total, 267 patients [median age 58 (range: 27-85) years old] with LACC underwent 18F-FDG PET/CT prior to any treatment. The maximum standardized uptake values (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesion and metastatic lymph nodes were measured on PET/CT and correlated with clinicopathological features and progression-free survival (PFS). The median follow-up was 36.52 (range: 3.09-61.29) months. During the observation period, 80 (30.0%) patients exhibited disease progression. Univariate analysis showed that FIGO stage, concurrent chemoradiotherapy (CRT), serum level of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC-Ag), primary tumor MTV (pMTV) and TLG (pTLG), lymph nodes SUVmax (nSUVmax) and TLG (nTLG), and total metabolic activity (sMTV, sTLG) were associated with PFS. nSUVmax ≥ 5.29, CEA ≥ 7.11ng/ml and deficiency of concurrent CRT were independent risk factor for PFS (p = 0.006, p = 0.008, p = 0.014). The 3-year PFS for patients with high nSUVmax were 42.2% compared to 56.3% for low nSUVmax values. Pretreatment cervical and lymph nodes metabolic parameters were associated with PFS in patients with LACC.

Prognostic thresholds of fluorine-18 fluorodeoxyglucose-positron emission tomography mean and maximum standardized uptake values for survival and nodal involvement in lung neuroendocrine neoplasms.

The mean standardized uptake value (SUVmean) and maximum standardized uptake value (SUVmax) on fluorine-18 fluorodeoxyglucose-positron emission tomography are prognostic biomarkers for survival and nodal involvement in non-small-cell lung cancer but their prognostic value in lung neuroendocrine neoplasms (NENs) remains unexplored. In this study, we aimed to examine whether they are also prognostic biomarkers for survival and nodal involvement in lung NENs. We retrospectively studied patients with typical carcinoid, atypical carcinoid or large cell neuroendocrine carcinoma who had been radically resected at our institution between 2008 and 2020. We measured SUVmean and SUVmax on all primary tumours and lymph nodes that were clinically and/or pathologically involved. We dichotomized the patients into groups of high or low SUVmean and SUVmax of the primary tumour using time-dependent receiver operating characteristic curves and compared their overall survival using Kaplan-Meier curves and Cox models. Lastly, we predicted the patients' pathological nodal status with SUVmean and SUVmax of the lymph nodes using binomial logistic models. The study included 245 patients. Patients died earlier if their SUVmean of the primary tumour exceeded 3.9 [hazard ratio 1.97, 95% confidence interval (CI) 1.27-3.04, P = 0.002] or SUVmax exceeded 5.3 (hazard ratio 1.85, 95% CI 1.20-2.87, P = 0.006). Likewise, patients had a higher risk of pathological nodal involvement if their SUVmean of the lymph nodes exceeded 3.3 (odds ratio 10.00, 95% CI 2.59-51.01, P = 0.002) or SUVmax exceeded 4.2 (odds ratio 4.00, 95% CI 1.20-14.65, P = 0.028). The fluorine-18 fluorodeoxyglucose-positron emission tomography SUVmean and SUVmax are strong prognostic biomarkers for survival and nodal involvement in lung NENs and could be important guides for making treatment decisions.

18F-FAPI PET/CT performs better in evaluating mediastinal and hilar lymph nodes in patients with lung cancer: comparison with 18F-FDG PET/CT

BackgroundThe aim of this study was to evaluate the efficacy of fluorine 18 (18F) labeled fibroblast activation protein inhibitor (FAPI) in identifying mediastinal and hilar lymph node metastases and to develop a model to quantitatively and repeatedly identify lymph node status.MethodsTwenty-seven patients with 137 lymph nodes were identified by two PET/CT images. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of lymph node status were analyzed, and the optimal cut-off value was identified by ROC analysis.ResultsThe SUVmax of metastatic lymph nodes on 18F-FAPI was higher than that on 18F-FDG PET/CT (10.87 ± 7.29 vs 6.08 ± 5.37, p < 0.001). 18F-FAPI presented much greater lymph node detection sensitivity, specificity, accuracy, PPV and NPV than 18F-FDG PET/CT (84% vs. 71%; 92% vs. 67%; 90% vs. 69%, 84% vs. 52%, and 92% vs. 83%, respectively). Additionally, the diagnostic effectiveness of 18F-FAPI in small lymph nodes was greater than that of 18F-FDG PET/CT (specificity: 96% vs. 72%; accuracy: 93% vs. 73%; PPV: 77% vs. 33%, respectively). Notably, the optimal cut-off value for specificity and PPV of 18F-FAPI SUVmax was 5.3; the optimal cut-off value for sensitivity and NPV was 2.5.Conclusion18F-FAPI showed promising diagnostic efficacy in metastatic mediastinal and hilar lymph nodes from lung cancer patients, with a higher SUVmax, especially in small metastatic nodes, compared with 18F-FDG. In addition, this exploratory work recommended optimal SUVmax cutoff values to distinguish between nonmetastatic and metastatic lymph nodes, thereby advancing the development of image-guided radiation.Trial registration ClinicalTrials.gov identifier: ChiCTR2000036091.

Prognostic significance of 18F-Fluorodeoxyglucose positron-emission tomography parameters in patients with biliary tract cancers: a meta-analysis.

Numerous previous studies have assessed the prognostic role of 18F-fluorodeoxyglucose positron-emission tomography (18F FDG PET) in patients with biliary tract cancer (BTC), but those results were inconsistent. The present study aims to determine the predictive value of 18F FDG PET in BTC patients via a meta-analysis. The underlying studies related to 18F FDG PET and BTC patients` outcomes were searched and identified in the online databases. The interested parameters include total lesion glycolysis (TLG), metabolic tumor volume (MTV), primary tumor and metastatic lymph node (LN) maximum standardized uptake value (SUVmax), as well as change of SUVmax (ΔSUVmax) during treatment. Overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS) were considered as the primary endpoints. Hazard ratio (HR) and corresponding 95% confidence intervals (CIs) were defined as the effective measure and calculated by a pooled analysis. Publication bias was assessed by funnel plot, Bagg's and Egger's tests. Totally, 23 studies involving 1478 patients were included in the present meta-analysis. After a pooled analysis, it revealed that a high SUVmax was significantly associated with a poor OS (HR:2.07, 95%CI: 1.74-2.46, P = 0.000) and DFS (HR: 2.28, 95%CI: 1.53-3.41, P = 0.000). In addition, an increased TLG level contributed to a shorter OS (HR:1.91, 95%CI: 1.26-2.90, P = 0.002) and DFS (HR: 4.34, 95%CI: 1.42-13.27, P = 0.01). Moreover, we confirmed that an elevated MTV was significantly associated with increased mortality (HR:2.04, 95%CI:1.26-3.31, P = 0.004) and disease relapse (HR: 3.88, 95%CI:1.25-12.09, P = 0.019) risks. Besides, the present study uncovered that increased ΔSUVmax could predict poor OS (HR:1.26, 95%CI:1.06-1.50, P = 0.008) instead of PFS (HR: 1.96, 95%CI: 0.82-4.72, P = 0.280). Lastly, we found that LN SUVmax did not link to OS (HR: 1.49, 95%CI: 0.83-2.68, P = 0.178). No obvious publication bias was detected in the present study. 18F FDG PET parameters, including SUVmax, TLG, MTV, and ΔSUVmax, could be applied as convenient and reliable factors for predicting BTC patients` outcomes.

The systemic impact of different COVID-19 vaccines in 2-[18F] FDG-PET/CT

Austria started its COVID-19-vaccination program in December 2020 with three different vaccines. As the vaccination program continues, we encountered increased 2-[18F] FDG-activity not only in axillary lymph nodes ipsilateral to the injection site but also in other organs. The aim of this retrospective study is to present results of the metabolic activity of ipsilateral axillary lymph nodes, liver, blood pool, spleen, and bone marrow after three different vaccines. To our knowledge, this is the first study to examine systemic response changes in relation to time after COVID-19 vaccination using three different vaccines. The collected data of 220 eligible vaccinated patients (127 with BioNTech/Pfizer BNT162b2, 61 with Moderna, and 32 with AstraZeneca) examined with 2-[18F] FDG-PET/CT were enrolled. The PET/CT examinations were evaluated from day 1 to day 135 (SD: 23.2, median: 26) after different vaccinations. Seventy-one out of these 220 patients underwent a pre-vaccination 2-[18F] FDG -PET/CT. SUVmax of axillary node(s), and blood pool, liver, spleen, and bone marrow as reference organs were calculated. The ratio of SUVmax activity of axillary lymph node to reference organs was also compared in all patients. The tracer activity dynamics were investigated in three different vaccines. After BioNTech/Pfizer vaccination 2-[18F] FDG activity in axillary lymph nodes shows a steady decrease in all patients. Ten days after vaccination the 2-[18F] FDG uptake was at its highest activity. Seventy days after vaccination, tracer activity is not different from the background activity of 2-[18F] FDG in the axillary region. This result also applies to other two vaccines; however, in the 4th week after Moderna vaccination SUVmax in lymph nodes showed the highest peak of tracer activity. With AstraZeneca the highest activity was at the earlier days. There was no significant statistical difference of SUVmax of lymph nodes or its ratios to other reference organs between three groups of vaccines. SUVmax in lymph nodes was statistically significant lower than SUVmax in the liver, spleen, and bone marrow with p-values of < 0.001, 0.044, and 0.001, respectively. In the group of 71 patients with a pre-vaccination PET/CT examination, the median SUVmax of lymph nodes increased significantly after vaccination from 0.82 (IQR 0.59–1.38) to 1.80 (IQR 1.07–3.89)(p < 0.001). In contrast median tracer activity in the liver decreased from 3.37 (IQR 2.83–3.91) to 3.11 (2.56–3.70) (p = 0.032). There was no significant change of tracer activity after vaccination in other reference regions (mediastinum, spleen, and bone marrow). In this group of 71 patients, there was also no significant difference in tracer activity in different types of vaccines. Local site and ipsilateral axillary lymph node activity in 2-[18F] FDG PET/CT after COVID19-vaccination is suggested in many studies. The main challenge is recognizing the changes in lymph nodes during time after vaccination to minimize false interpretation, foremost in patients with oncological diagnoses. Moreover, different vaccines cause different system metabolic changes. The knowledge of vaccine type, the time interval between vaccination and PET/CT scan is essential, especially in therapy evaluation.

Clinico-biological-radiomics (CBR) based machine learning for improving the diagnostic accuracy of FDG-PET false-positive lymph nodes in lung cancer

BackgroundThe main problem of positron emission tomography/computed tomography (PET/CT) for lymph node (LN) staging is the high false positive rate (FPR). Thus, we aimed to explore a clinico-biological-radiomics (CBR) model via machine learning (ML) to reduce FPR and improve the accuracy for predicting the hypermetabolic mediastinal–hilar LNs status in lung cancer than conventional PET/CT.MethodsA total of 260 lung cancer patients with hypermetabolic mediastinal–hilar LNs (SUVmax ≥ 2.5) were retrospectively reviewed. Patients were treated with surgery with systematic LN resection and pathologically divided into the LN negative (LN-) and positive (LN +) groups, and randomly assigned into the training (n = 182) and test (n = 78) sets. Preoperative CBR dataset containing 1738 multi-scale features was constructed for all patients. Prediction models for hypermetabolic LNs status were developed using the features selected by the supervised ML algorithms, and evaluated using the classical diagnostic indicators. Then, a nomogram was developed based on the model with the highest area under the curve (AUC) and the lowest FPR, and validated by the calibration plots.ResultsIn total, 109 LN− and 151 LN + patients were enrolled in this study. 6 independent prediction models were developed to differentiate LN− from LN + patients using the selected features from clinico-biological-image dataset, radiomics dataset, and their combined CBR dataset, respectively. The DeLong test showed that the CBR Model containing all-scale features held the highest predictive efficiency and the lowest FPR among all of established models (p < 0.05) in both the training and test sets (AUCs of 0.90 and 0.89, FPRs of 12.82% and 6.45%, respectively) (p < 0.05). The quantitative nomogram based on CBR Model was validated to have a good consistency with actual observations.ConclusionThis study presents an integrated CBR nomogram that can further reduce the FPR and improve the accuracy of hypermetabolic mediastinal–hilar LNs evaluation than conventional PET/CT in lung cancer, thereby greatly reducing the risk of overestimation and assisting for precision treatment.

Quantitative and clinical implications of the EARL2 versus EARL1 [18F]FDG PET-CT performance standards in head and neck squamous cell carcinoma

BackgroundThe EANM Research Ltd. (EARL) guidelines give recommendations for harmonization of [18F]FDG PET-CT image acquisition and reconstruction, aiming to ensure reproducibility of quantitative data between PET scanners. Recent technological advancements in PET-CT imaging resulted in an updated version of the EARL guidelines (EARL2). The aim of this study is to compare quantitative [18F]FDG uptake metrics of the primary tumor and lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC) on EARL2 versus EARL1 reconstructed images and to describe clinical implications for nodal staging and treatment.MethodsForty-nine consecutive patients with HNSCC were included. For all, both EARL1 and EARL2 images were reconstructed from a singular [18F]FDG PET-CT scan. Primary tumors and non-necrotic lymph nodes ≥ 5 mm were delineated on CT-scan. In the quantitative analysis, maximum standardized uptake values (SUVmax) and standardized uptake ratios (SURmax, i.e., SUVmax normalized to cervical spinal cord uptake) were calculated for all lesions on EARL1 and EARL2 reconstructions. Metabolic tumor volume (MTV) and total lesion glycolysis were compared between EARL1 and EARL2 using different segmentation methods (adaptive threshold; SUV2.5/3.5/4.5; SUR2.5/3.5/4.5; MAX40%/50%). In the qualitative analysis, each lymph node was scored independently by two nuclear medicine physicians on both EARL1 and EARL2 images on different occasions using a 4-point scale.ResultsThere was a significant increase in SUVmax (16.5%) and SURmax (9.6%) of primary tumor and lymph nodes on EARL2 versus EARL1 imaging (p < 0.001). The proportional difference of both SUVmax and SURmax between EARL2 and EARL1 decreased with increasing tumor volume (p < 0.001). Absolute differences in MTVs between both reconstructions were small (< 1.0 cm3), independent of the segmentation method. MTVs decreased on EARL2 using relative threshold methods (adaptive threshold; MAX40%/50%) and increased using static SUV or SUR thresholds. With visual scoring of lymph nodes 38% (11/29) of nodes with score 2 on EARL1 were upstaged to score 3 on EARL2, which resulted in an alteration of nodal stage in 18% (6/33) of the patients.ConclusionsUsing the EARL2 method for PET image reconstruction resulted in higher SUVmax and SURmax compared to EARL1, with nodal upstaging in a significant number of patients.

Contribution of FDG-PET in the diagnostic assessment of cervical lymph node metastasis in Oral Cavity Squamous Cell Carcinoma (OCSCC)

IntroductionThe main objective of this study was to evaluate the contribution of FDG-PET in the diagnostic assessment of cervical lymph node metastasis in Oral Cavity Squamous Cell Carcinoma (OCSCC) and to advance a diagnostic threshold value for SUVmax in carcinomatous cervical lymph node. Methods47 patients with OCSCC and suspicious cervical lymph node involvement (cN+) on FDG-PET were included in this retrospective study. The primary outcome was cervical lymph node SUVmax based on histological cervical metastatic disease (« gold standard »). ResultsAmong the 77 cervical lymph nodes considered suspicious on patients’ FDG-PET, 50 were really metastatic on histological examination. The lymph node SUVmax with metastatic involvement on histological examination was 4.6 ± 3.9 [2.6 – 23.7] versus 3.6 ± 1.2 [2 – 7.3] without carcinomatous involvement (p = 0.004). The lymph node size was not statistically significant according to metastatic disease (p = 0.28). DiscussionA cervical lymph node SUVmax value of less than 2.6 on FDG-PET would suggest non-metastatic lymph node involvement. Supra Omohyoid Neck Dissection (SOHND) could therefore be performed in OCSCC when the SUVmax of the cervical lymph node is below this value in order to reduce the surgical morbidity of dissection of the lower internal jugular chain (Level IV).

Qualitative and quantitative PET/MRI in the evaluation of axillary lymph node metastasis in patients with breast cancer

Objective: To investigate the value of qualitative and quantitative PET/MRI in the evaluation of axillary lymph node metastasis in patients with breast cancer. Methods: A total of 33 patients with breast cancer underwent preoperative PET/MRI examinations in Jingling Hospital from February to August in 2022 were retrospectively collected. All these patients were female, aged from 34 to 73 (51.4±11.3) years. Histopathological results and follow-up data were deemed as the referent standard, and the images were independently evaluated by two experienced breast imaging radiologists. The qualitative PET/MRI evaluation procedures were designed to evaluated the MRI alone to classify the axillary lymph nodes firstly, and then, the axillary lymph nodes status was reclassified by combining MRI and PET images. The net reclassification improvement index (NRI) was calculated using the R Programming Language (RStudio). The quantitative PET/MRI evaluation of the maximum standard uptake value (SUVmax) of axillary lymph nodes were measured by two radiologists, respectively, and the average value was compared with the referent standard to conduct a receiver operating characteristic (ROC) curve to select the optimal cutoff value of SUVmax. Based on the cutoff value and MRI classification results, axillary lymph nodes status was divided into quantitative PET/MRI positive or negative. The sensitivity, specificity and accuracy of MRI and quantitative PET/MRI in evaluating axillary lymph node metastasis were compared, and the area under the ROC curve (AUC) was compared. Results: There was no significant difference in sensitivity, specificity and accuracy between MRI and quantitative PET/MRI in evaluating lymph node metastasis of breast cancer (81.82% vs 95.46%; 81.82% vs 100%; 81.82% vs 96.97%) (all P>0.05). The AUC had a statistically significant difference [0.82 (0.65 to 0.93) vs 0.98 (0.85 to 1.00), P=0.026)]. According to the referent standard, in the 11 cases without ipsilateral axillary lymph node metastasis, the SUVmax was 0.83±0.18, while in the 22 cases with ipsilateral axillary lymph node metastasis, the SUVmax was [4.36 (1.77, 5.85)]. Compared with MRI alone, the NRI of qualitative PET/MRI in evaluating lymph node metastasis was 36.36% (P=0.021). Conclusion: Compared with MRI alone, quantitative PET/MRI has a higher AUC for evaluating axillary lymph node metastasis in patients with breast cancer, and qualitative PET/MRI had a better reclassification power in the evaluation of axillary lymph node metastasis.