Preoperative FDG-PET Research Articles

Comparison of Sentinel Lymph Node Sampling with Positron Emission Tomography in the Evaluation of Axillary Lymph Node Involvement in Breast Cancer Patients

Objectives Axillary lymph node status is the most important prognostic factor in breast cancer patients.: This study was carried out to evaluate the diagnostic accuracy of FDG-PET/CT as a noninvasive technique and intraoperative frozen biopsy of sentinel lymphadenectomy (SLNB) in detecting axillary lymph node metastasis. Materials and Methods This study was carried out retrospectively on 44 patients diagnosed with breast cancer, who underwent preoperative FDGPET/ CT imaging and intraoperative SLNB, at the General Surgery Clinic of Istanbul Medeniyet University Göztepe Training and Research Hospital. The axilla was clinically negative in all patients. Preopative FDG-PET/CT imaging and intraoperative SLNB were performed. FDG-PET/CT results were compared with the histopathological results of SLNB and axillary lymph node dissection (ALND). Results According to the pathology results of axillary dissection, metastatic nodes were detected in 22 of 44 cases, and FDG-PET/ CT imaging gave false-negative results in 10. The number of false negative cases of SLNB was 3; Axillary involvement was detected as a result of pathology in one of them, while the others were evaluated as skip metastases. The sensitivity of SLNB and FDG-PET/CT imaging was measured as 86.3% and 54.5%. The specificity values were 95.4% and 100%. FDG-PET/CT imaging has low sensitivity; specificity and positive predictive value were at acceptable levels Conclusion: The sensitivity of FDG-PET/CT imaging is low in detecting axillary involvement, and SLNB is needed in those with negative axillary involvement in FDG-PET/ CT imaging. In our study, SLNB examination was superior to FDG-PET/CT imaging in detecting axillary nodal status. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1083-1094

FDG-PET associations with pathological response and survival with neoadjuvant immunotherapy for melanoma.

9523 Background: This study sought to describe the changes seen with FDG-PET following neoadjuvant immunotherapy in melanoma patients (pts), and explore associations with pathological response and recurrence-free survival (RFS). Methods: Two prospective clinical trial cohorts of stage III pts with RECIST measurable nodal melanoma were included; 1) NeoTrio, 13 pts received 2 doses of preoperative pembrolizumab alone, and 2) NeoPele, 20 pts received 2 doses of pembrolizumab and 5 weeks of lenvatinib preoperatively. All pts underwent baseline and week 6 (preoperative) FDG-PET assessments and all had surgery. PET responses were evaluated based on the modified EORTC criteria. In addition to the standard categories Complete Metabolic Response (CMR), Partial Metabolic Response (PMR), Stable Metabolic Disease (SMD), and Progressive Metabolic Disease (PMD), a novel category was established, near-CMR, where the maximum standardized uptake value (SUVmax) decreased by more than 90%. PET responses were determined while blinded to the outcome data. Pathological response was determined as per INMC criteria. Results: 33 pts were included, 67% male, median age 65 years, 48% BRAF mutant. Pathological response, PET response and correlations are shown in the Table. All 8 (24%) pts achieving CMR or near-CMR obtained major pathologic response (MPR), while the 14 pts (42%) with PMR had variable pathological outcomes (57% MPR, 21% pPR, 21% pNR). For the 6 pts with PMD, 5 (83%) had pNR and the one pts who achieved pCR recurred with brain metastases. After a median 29.9 mo follow-up (95% CI 27.0-33.1), PET response associated with RFS; those with CMR/near CMR had 100% 24mo RFS (nil recurrences to date) while those with PMR or SMD had inferior survival (79% and 80% 24mo RFS), and those with PMD the worst outcomes (17% 24mo RFS, all pts except one have recurred) (p=0.0029). The predictive value of PET and pathology for RFS was assessed using the Cox Proportional Hazards model. 12- and 24-month RFS AUCs of PET and pathology response were similar at 81.5% (95% CI: 67.7-95.3) vs. 80.9% (95% CI: 67.8-93.9), and 83.3% (95% CI: 69.1-97.5%) vs. 80.8% (95% CI: 66.6-94.9), respectively. Conclusions: FDG-PET demonstrates utility in predicting pathological response and survival with neoadjuvant immunotherapy in melanoma. PET may identify pts who are not going to be pathological responders and who have the worst survival outcomes, enabling a potential switch of neoadjuvant systemic therapy. [Table: see text]

Hypometabolism in the Posteromedial Temporal and Medial Occipital Cortex on Preoperative 2-Deoxy-2-(18F) Fluoro-D-Glucose Positron Emission Tomography Suggests Exacerbation of Visual Field Defects After Surgery for Temporal Lobe Epilepsy: A Retrospective Long-Term Follow-Up Study

ObjectiveSurgery is a good treatment option for drug-resistant temporal lobe epilepsy (TLE). 2-deoxy-2-(18F) fluoro-D-glucose (FDG) positron emission tomography (PET) is used to detect epileptic foci as hypometabolic lesions in presurgical evaluation. Visual field defects (VFDs) in the contralateral homonymous upper quadrant are common postoperative complications in TLE. This study aimed to quantify VFDs using pattern deviation probability plots (PDPPs) and examine the effect of hypometabolism in FDG-PET on VFDs. MethodsThis study included 40 patients. Both visual fields were assessed using the Humphrey field analyzer (HFA) preoperatively and 3 months and 2 years postoperatively. PDPPs with <0.5% confidence level counted in the contralateral homonymous upper quadrant. FDG-PET results were compared between groups with (15 patients) and without (24 patients) hypometabolism in the optic radiation. ResultsAll 40 patients were evaluated by HFA at 3 months postoperatively and 39 at 2 years postoperatively. The incidence of VFDs 3 months postoperatively was 35/40 (87.5%), and 17/40 (42.5%) patients had severe VFDs. In cases of surgery on the left temporal lobe, ipsilateral eyes appeared to be more significantly affected than contralateral eyes. VFDs were more severe in patients with FDG hypometabolism than in those without hypometabolism in posteromedial temporal and medial occipital cortex (P < 0.01); however, 85% of patients with FDG hypometabolism had a reduced VFD 2 years postoperatively. ConclusionPDPP counting is useful for quantifying VFDs. Preoperative dysfunction indicated by preoperative FDG-PET in the posteromedial temporal and medial occipital cortex could enhance VFDs early after TLE surgery.

Machine learning techniques based on 18F-FDG PET radiomics features of temporal regions for the classification of temporal lobe epilepsy patients from healthy controls.

This study aimed to investigate the clinical application of 18F-FDG PET radiomics features for temporal lobe epilepsy and to create PET radiomics-based machine learning models for differentiating temporal lobe epilepsy (TLE) patients from healthy controls. A total of 347 subjects who underwent 18F-FDG PET scans from March 2014 to January 2020 (234 TLE patients: 25.50 ± 8.89 years, 141 male patients and 93 female patients; and 113 controls: 27.59 ± 6.94 years, 48 male individuals and 65 female individuals) were allocated to the training (n = 248) and test (n = 99) sets. All 3D PET images were registered to the Montreal Neurological Institute template. PyRadiomics was used to extract radiomics features from the temporal regions segmented according to the Automated Anatomical Labeling (AAL) atlas. The least absolute shrinkage and selection operator (LASSO) and Boruta algorithms were applied to select the radiomics features significantly associated with TLE. Eleven machine-learning algorithms were used to establish models and to select the best model in the training set. The final radiomics features (n = 7) used for model training were selected through the combinations of the LASSO and the Boruta algorithms with cross-validation. All data were randomly divided into a training set (n = 248) and a testing set (n = 99). Among 11 machine-learning algorithms, the logistic regression (AUC 0.984, F1-Score 0.959) model performed the best in the training set. Then, we deployed the corresponding online website version (https://wane199.shinyapps.io/TLE_Classification/), showing the details of the LR model for convenience. The AUCs of the tuned logistic regression model in the training and test sets were 0.981 and 0.957, respectively. Furthermore, the calibration curves demonstrated satisfactory alignment (visually assessed) for identifying the TLE patients. The radiomics model from temporal regions can be a potential method for distinguishing TLE. Machine learning-based diagnosis of TLE from preoperative FDG PET images could serve as a useful preoperative diagnostic tool.

Relationship between Systemic Inflammatory Markers, GLUT1 Expression, and Maximum 18F-Fluorodeoxyglucose Uptake in Non-Small Cell Lung Carcinoma and Their Prognostic Significance

Factors involved in inflammation and cancer interact in various ways with each other, and biomarkers of systemic inflammation may have a prognostic value in cancer. Glucose transporter 1 (GLUT1) plays a pivotal role in glucose transport and metabolism and it is aberrantly expressed in various cancer types. We evaluated the differential expression of GLUT1, along with 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in non-small-cell lung cancer (NSCLC), and then analyzed their prognostic significance. A total of 163 patients with resectable NSCLC were included in this study. Tumor sections were immunohistochemically stained for GLUT1 and GLUT3. Maximum standardized uptake value (SUVmax) was measured by preoperative FDG-PET, and neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR) were derived from pretreatment blood count. GLUT1 and GLUT3 was positively expressed in 74.8% and 6.1% of the NSCLC tissues, respectively. GLUT1 expression was significantly correlated with squamous cell carcinoma histology, poor differentiation, high pathologic stage, old age, male, smoking, and high SUVmax (>7) (all p < 0.05). The squamous cell carcinoma and smoker group also showed significantly higher SUVmax (both p < 0.001). Systemic inflammation markers, including NLR, PLR, and LMR, were positively correlated with high SUVmax (all p < 0.05). High GLUT1 expression, high SUVmax, high NLR, and low LMR, were significantly associated with poor overall survival in patients with NSCLC. However, in the multivariate survival analysis, LMR was an independent prognostic factor overall (HR 1.86, 95% CI 1.05-3.3) and for the stage I/II cohort (HR 2.3, 95% CI 1.24-4.3) (all p < 0.05). Systemic inflammatory markers-NLR, PLR, and LMR are strongly correlated with the SUVmax and are indicators of aggressive tumor behavior. Specifically, LMR is a promising prognostic biomarker in NSCLC patients.

Correlation Between Tumor Uptake on FDG-PET and Malignant Features in Esophageal Squamous Cell Carcinoma After Neoadjuvant Chemotherapy Followed by Surgery.

To identify the correlations between the 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) images and the pathological features and recurrence among patients with esophageal squamous cell carcinoma (ESCC) who were administered neoadjuvant chemotherapy (NAC) followed by surgery. We assessed the correlations between the maximum standardized uptake value (SUVmax) of primary tumors as reflected on preoperative FDG-PET images, the pathological features, and cancer recurrence in 124 patients with locally advanced ESCC, who were treated with NAC and esophagectomy. The pre-NAC SUVmax significantly differed for the ypT status and venous invasion (VI). The post-NAC SUVmax (post-SUVmax) significantly differed for the ypT and ypN status, VI, lymphatic invasion (LI), pathological tumor response, down-staging, and recurrence. The decrease in SUVmax before and after NAC (ΔSUVmax) significantly differed for ypT status, LI, VI, pathological tumor response, down-staging, and recurrence. The survivals were significantly stratified according to the optimal cutoffs of SUVmax for predicting recurrence (post- and ΔSUVmax cutoffs: 4.2 and 30, respectively; all p<0.0001). Moreover, multivariate analysis showed that the post- and ΔSUVmax were independent predictive factors for recurrence-free survival. The SUVmax on preoperative FDG-PET can predict the degree of aggressiveness of the tumor in locally advanced ESCC treated with NAC.

Regional lymph node metastasis detected on preoperative CT and/or FDG-PET may predict early recurrence of pancreatic adenocarcinoma after curative resection

The objective of this study was to evaluate the role of regional lymph node (LN) metastasis detected on preoperative CT and/or 18F-fluoro-2-deoxyglucose-positron emission tomography (FDG-PET) scans in the prediction of early tumor recurrence after curative surgical resection of pancreatic ductal adenocarcinoma (PDAC). This retrospective study included 137 patients who underwent upfront surgery with R0 resection of PDAC between 2013 and 2016. Regional LN metastasis was identified using two criteria: positive findings for regional LN metastasis on either preoperative CT or FDG-PET scans (LNOR), or on both preoperative CT and FDG-PET scans (LNAND). A total of 55 patients had early tumor recurrence within 12 months after curative resection. Univariable and multivariable Cox proportional hazard regression analysis showed that preoperative carbohydrate antigen 19–9 (CA19-9) levels, preoperative locally advanced status, and regional LN metastasis (both LNOR and LNAND criteria) were significant risk factors for early recurrence. Positive LNOR and LNAND showed significantly poorer recurrence-free survival compared to negative regional LN metastasis groups (p = 0.048 and p = 0.020, respectively). Compared with the LNAND criteria, the LNOR criteria provided higher sensitivity (22.4% vs. 15.5%, p = 0.046) and a higher negative predictive value (61.9% vs. 59.8%, p = 0.046). The LNOR definition provided more sensitive and accurate performance in diagnosing preoperative regional LN metastasis.

FDG-PET Predicts Neoadjuvant Therapy Response and Survival in Borderline Resectable/Locally Advanced Pancreatic Adenocarcinoma.

Neoadjuvant therapy (NAT) is used in borderline resectable/locally advanced (BR/LA) pancreatic ductal adenocarcinoma (PDAC). Anatomic imaging (CT/MRI) poorly predicts response, and biochemical (CA 19-9) markers are not useful (nonsecretors/nonelevated) in many patients. Pathologic response highly predicts survival post-NAT, but is only known postoperatively. Because metabolic imaging (FDG-PET) reveals primary tumor viability, this study aimed to evaluate our experience with preoperative FDG-PET in patients with BR/LA PDAC in predicting NAT response and survival. We reviewed all patients with resected BR/LA PDAC who underwent NAT with FDG-PET within 60 days of resection. Pre- and post-NAT metabolic (FDG-PET) and biochemical (CA 19-9) responses were dichotomized in addition to pathologic responses. We compared post-NAT metabolic and biochemical responses as preoperative predictors of pathologic responses and recurrence-free survival (RFS) and overall survival (OS). We identified 202 eligible patients. Post-NAT, 58% of patients had optimization of CA 19-9 levels. Major metabolic and pathologic responses were present in 51% and 38% of patients, respectively. Median RFS and OS times were 21 and 48.7 months, respectively. Metabolic response was superior to biochemical response in predicting pathologic response (area under the curve, 0.86 vs 0.75; P&lt;.001). Metabolic response was the only univariate preoperative predictor of OS (odds ratio, 0.25; 95% CI, 0.13-0.40), and was highly correlated (P=.001) with pathologic response as opposed to biochemical response alone. After multivariate adjustment, metabolic response was the single largest independent preoperative predictor (P&lt;.001) for pathologic response (odds ratio, 43.2; 95% CI, 16.9-153.2), RFS (hazard ratio, 0.37; 95% CI, 0.2-0.6), and OS (hazard ratio, 0.21; 95% CI, 0.1-0.4). Among patients with post-NAT resected BR/LA PDAC, FDG-PET highly predicts pathologic response and survival, superior to biochemical responses alone. Given the poor ability of anatomic imaging or biochemical markers to assess NAT responses in these patients, FDG-PET is a preoperative metric of NAT efficacy, thereby allowing potential therapeutic alterations and surgical treatment decisions. We suggest that FDG-PET should be an adjunct and recommended modality during the NAT phase of care for these patients.

High SUVmax on routine pre-operative FDG-PET predicts early recurrence in pancreatic and peri-ampullary cancer.

SUVmax of a primary pancreatic tumour on FDG-PET/CT (SUVmax-p) may predict early post-operative recurrence. This has not been tested in the context of routine pre-operative FDG-PET/CT. It is also unknown whether this association exists independent of local residual tumour. FDG-PET/CT was performed routinely prior to resection of pancreatic or peri-ampullary adenocarcinoma between 2008 and 2012 as part of a previous prospective study. We compared SUVmax-p according to whether recurrence was diagnosed within 6 months of resection. We also determined the odds ratio for recurrence within 6 months for multiple cut-points of SUVmax-p. This analysis was repeated exclusively for patients who had resection with clear surgical margins (R0). Of 56 patients from the initial study 23 underwent resection and were eligible. Recurrence within 6 months was associated with higher median SUVmax-p (5.9 vs 3.5; p=0.04). This was also observed in 12 patients who underwent R0 resection (6.5 vs 2.2; p=0.05). The cut-point with the highest odds for recurrence within 6 months for both groups was SUVmax-p≥5.5 (OR=10.8, CI=1.56-109; OR[R0]=24.0, CI=1.64-1020). SUVmax-p on routine FDG-PET/CT is useful for identifying patients likely to benefit from additional pre-operative staging or neoadjuvant therapy, even where clear margins can confidently be achieved.

Prognostic value of quantitative parameters for esophageal squamous cell carcinoma determined by preoperative FDG-PET after trimodal therapy

BackgroundAssociations between tumor metabolic and volumetric parameters determined by preoperative 18F-fluorodeoxyglucose–positron emission tomography and survival in patients with esophageal squamous cell carcinoma who underwent trimodal therapy have not been fully investigated. MethodsWe evaluated relationships between reductions in maximal standardized uptake value, metabolic tumor volume, and total lesion glycolysis in primary tumors on 18F-fluorodeoxyglucose–positron emission tomography images between before and after neoadjuvant chemoradiotherapy and the survival of 120 patients with esophageal squamous cell carcinoma who underwent neoadjuvant chemoradiotherapy followed by surgery. ResultsThe optimal cutoffs of Δ maximal standardized uptake value, Δ metabolic tumor volume, and Δ total lesion glycolysis were defined to statistically yield the largest differences in recurrence-free survival for good and poor positron emission tomography responders to neoadjuvant chemoradiotherapy (cutoffs: 70%, 85%, and 90%, respectively). These cutoff values significantly stratified overall survival (Δ maximal standardized uptake value, P = .004; Δ metabolic tumor volume, P = .001; Δ total lesion glycolysis, P < .0001). Univariate analysis showed that Δ maximal standardized uptake value (hazard ratio, 0.50; 95% confidence interval, 0.32–0.79; P = .003), Δ metabolic tumor volume (hazard ratio, 0.50; 95% confidence interval, 0.31–0.81; P = .004), and Δ total lesion glycolysis (hazard ratio, 0.37; 95% confidence interval, 0.23–0.61; P < .001) were statistically significant for recurrence-free survival. Furthermore, Δ metabolic tumor volume (hazard ratio, 0.45; 95% confidence interval, 0.27–0.76; P = .003) and Δ total lesion glycolysis (hazard ratio, 0.37; 95% confidence interval, 0.22–0.63; P < .001) were independent factors for recurrence-free survival in multivariate analyses that included preoperative and pathological factors. ConclusionTogether with significant pathological prognostic factors, Δ metabolic tumor volume and Δ total lesion glycolysis were valuable for patients with esophageal squamous cell carcinoma who received trimodal therapy. Thus, preoperative 18F-fluorodeoxyglucose–positron emission tomography is a useful and noninvasive diagnostic tool that might facilitate tailoring optimal therapies for locally advanced esophageal squamous cell carcinoma.

High SUVmax of a Primary Pancreatic Malignancy on Routine Pre-Operative FDG-PET Is Associated with Recurrence within 6 Months of Resection

Introduction: Oncological pancreatic resection is a costly and morbid procedure. A significant proportion of patients who undergo this treatment will have recurrence within 6 months and therefore have not received benefit from their surgery. More clinical parameters which aid patient selection are needed. Methods: All patients with potentially resectable pancreatic or peri-ampullary adenocarcinoma were eligible to undergo pre-operative FDG-PET/CT. Maximum standardized uptake value of the primary tumour (SUVmax-p) was compared between those with recurrence within 6 months of resection and those without. Using increments of 0.5 we divided the full range of SUVmax-p into discrete cut-points and determined the odds ratio of recurrence within 6 months for each. We repeated the same analysis exclusively for patients who had resection with clear surgical margins. Results: 23 patients who underwent resection of a pancreatic or peri-ampullary malignancy were included. Median SUVmax-p was 4.0 (IQR: 2.5-5.9). Recurrence within 6 months was associated with higher median SUVmax-p (5.9 vs 3.5; p=0.04). The cut-point with the highest odds ratio for recurrence within 6 months was SUVmax-p ≥ 5.5 (OR: 10.8; 95% CI: 1.56-109; p=0.01). 12 patients underwent margin negative resection. Recurrence within 6 months for this group remained associated with higher median SUVmax-p (6.5 vs 2.2; p=0.48), and SUVmax-p ≥ 5.5 remained the cut-point with the highest odds ratio for recurrence (OR: 24.0; 95% CI: 1.64-1020; p=0.02). Conclusion: SUVmax-p determined on routine pre-operative FDG-PET/CT is useful for identifying patients unlikely to benefit from pancreatic resection, irrespective of whether clear surgical margins can be achieved.

FDG-PET predicts bone invasion and prognosis in patients with oral squamous cell carcinoma

18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is widely used for tumor staging. This study sought to determine the relationship of preoperative primary tumor SUVmax (tSUVmax) with the clinicopathological features of patients with OSCC and to compare the prognostic ability of tSUVmax with that of other recurrence factors. Data of 340 patients with OSCC who were diagnosed, treated, and followed up at the Changhua Christian Hospital were retrospectively analyzed. Only patients with OSCC arising from gingiva, palate, floor of the mouth, and retromolar trigone and those who had received preoperative FDG-PET within 2 weeks before surgery were included. tSUVmax value > 9.2 was the strong predictor of bone invasion (area under the receiver operating characteristic curve, 0.844). tSUVmax value > 7.2 showed a strong association with advanced pathological T stage and recurrence factors and was associated with poor survival; tSUVmax > 7.2 showed stronger predictive power for poor disease-free survival (DFS) than pT stage and the other recurrence factors related to primary tumor. FDG-PET can be a useful supplement to contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging for diagnosing bone invasion by OSCC. The tSUVmax value was an independent predictor of DFS in this study.

Long term survival and outcomes from surgery in patients who have undergone pre-operative FDG-PET for pancreatic or peri-ampullary cancer

Long term survival and outcomes from surgery in patients who have undergone pre-operative FDG-PET for pancreatic or peri-ampullary cancer

Prognostic Values of SUVmax Value of PET/CT and CA19-9 as Biologic Markers in Patients with Pancreatic Ductal Adenocarcinoma

Among various prognostic factors of pancreatic cancer, most of clinical information before surgery is obtained by imaging modality. However tumor biologic characteristics also should be considered to decide treatment plan. Purpose of this study is to evaluate clinical usefulness of preoperative standard uptake value in 18F-fluorodeoxyglucose positron emission tomography and carbohydrate antigen as biologic markers for prognosis of resectable pancreatic ductal adenocarcinoma. 189 patients with pancreatic adenocarcinoma underwent preoperative FDG-PET testing were studied. SUVmax was calculated for each primary lesion. Patients who underwent neoadjuvant chemotherapy, R2 resection, and sequential resection were excluded. Analysis about correlation between SUVmax and clinicopathologic parameters was performed. C-tree statistical method was drawn to estimated cutoff values of SUVmax and CA19-9 for survival rate. Multivariate analysis was conducted to identify prognostic factors for overall survival. Median duration of overall survival was 26 months, five-year survival rate was 22.4%. C-tree analysis revealed the optimal cutoff values for SUVmax was 5.5 and that of CA19-9 was 150 about survival rate. When subjects were divided into three groups according to combination of SUVmax and CA19-9 values from C-tree (high group, SUVmax >5.5 and CA19-9>150, intermediate group and low group, SUVmax≤5.5 and CA19-9≤150), there was a significant 5YSR difference (5.6%, 24.3% and 36.5%, p < 0.001) The multivariate analysis revealed low BMI and high SUVmax and venous invasion were prognostic factor in overall survival. As biologic markers, SUVmax and CA19-9 are prognostic factors in pancreatic cancer patients. Especially, patients with high SUVmax and CA19-9 are not indication to upfront sugery.

Genomic Signature of the Standardized Uptake Value in 18F-Fluorodeoxyglucose Positron Emission Tomography in Breast Cancer.

The standardized uptake value (SUV), an indicator of the degree of glucose uptake in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), has been used for predicting the clinical behavior of malignant tumors. However, its characteristics have been insufficiently explored at the genomics level. Here, we aim to identify genomic signatures reflecting prognostic SUV characteristics in breast cancer (BRC). Through integrative genomic profiling of 3710 BRC patients, including 254 patients who underwent preoperative FDG-PET, we identified an SUV signature, which showed independent clinical utility for predicting BRC prognosis (hazard ratio [HR] 1.27, 95% confidence interval [CI] = 1.12 to 1.45, p = 2.23 × 10−4). The risk subgroups classified by the signature exhibited mutually exclusive mutation patterns of TP53 and PIK3CA and showed significantly different responsiveness to immunotherapy. Experimental assays revealed that a signaling axis defined by TP53–FOXM1 and its downstream effectors in glycolysis–gluconeogenesis, including LDHA, might be important mediators in the FDG-PET process. Our molecular characterizations support an understanding of glucose metabolism and poor prognosis in BRC with a high SUV, utilizable in clinical practice to assist other diagnostic tools.

Quantitative analysis of metabolic parameters at 18F-fluorodeoxyglucose positron emission tomography in predicting malignant potential of anterior mediastinal tumors.

To evaluate the utility of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) for predicting the malignancy of anterior mediastinal tumors, the present study retrospectively examined a total of 105 consecutive patients who underwent surgical resection of anterior mediastinal tumors at Gunma University Hospital after undergoing a preoperative FDG-PET scan. Patients were divided into benign and malignant groups in accordance with the following three classification systems: i) Clinical classification, benign or malignant (thymoma and carcinoma); ii) recurrence-based classification, low-risk recurrence (benign and low-risk thymoma) or high-risk recurrence (high-risk thymoma and carcinoma); and iii) pathological classification, benign (benign and thymoma) or malignant (carcinoma). The present study analyzed the differences between the benign and malignant groups in terms of FDG-PET parameters, including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG). The malignant group exhibited a significantly greater SUVmax than the benign group according to all classification systems. By contrast, there was only a slight difference between groups in volume-based metabolic parameters (MTV and TLG) using the clinical classification, and no intergroup differences using the recurrence-based and pathological classifications. The area under the curve in receiver-operating characteristic curve analysis for predicting malignancy was significantly greater for SUVmax than for volume-based metabolic parameters using all classification methods. The respective optimal cut-off value, sensitivity and specificity of SUVmax to predict malignancy were 1.77, 92.0 and 87.0% for the clinical classification, 2.54, 93.6 and 60.3% for the recurrence-based classification, and 5.15, 78.9 and 90.7% for the pathological classification. SUVmax was the most useful parameter for predicting the malignancy of anterior mediastinal tumors.

Relationship Between FDG Uptake and the Platelet/lymphocyte Ratio in Patients With Breast Invasive Ductal Cancer

We investigated the relationship between F18-fluorodeoxyglucose (FDG) uptake and the platelet/lymphocyte ratio (PLR), as both represent inflammation. We retrospectively analyzed the cases of 143 consecutive invasive ductal carcinoma patients who had undergone preoperative FDG-PET and surgery. We divided the patients into groups based on their maximum standardized uptake value (SUVmax) values: low (<2.5) and high (≥2.5) and based on their PLRs: low (<130) and high (≥130). We determined the relationships between the SUVmax or PLR and clinicopathological features. Seventy-three patients (51.0%) had a high SUVmax in their primary tumor. There were significant associations between SUVmax and the PLR. A multivariate analysis revealed that high PLR, but not NLR, was independent factor associated with a high SUVmax. Seventy-four patients (51.7%) had a high PLR; The factors significantly associated with high PLR were large tumor size, presence of node metastasis, presence of vascular invasion, high NLR, and high SUVmax. In breast cancer patients, the PLR is independently associated with the SUVmax, but not with recurrent disease. In breast cancer patients with a high SUVmax and/or PLR, these values may reflect the tumor microenvironment.

463P - Prediction of invasiveness in lung adenocarcinoma using machine learning algorithm based on 3D-CT imaging

BackgroundT factor depends on consolidation diameter in lung adenocarcinoma. Adenocarcinoma with short consolidation diameter could be indicated for sublobar resection. However, measurement of consolidation diameter under lung window in 2D-CT could be problematic, as the outline is not clear. We evaluated the relationship between consolidation lesion under mediastinal window in 3D-CT and pathological invasiveness, and aimed to predict invasiveness using machine learning algorithm. MethodsNinety-five patients who underwent surgical resection of lung adenocarcinoma that is less than 20 mm in diameter and has consolidation were analyzed retrospectively, in our Hospital from 2010 to 2016. The total tumor diameter and the volume and diameter of consolidation were analyzed using thin-slice CT and 3D-CT. Preoperative FDG-PET and serum CEA were also measured. Preinvasive lesion and minimally invasive adenocarcinoma were classified as pathologically non-invasive group, and invasive adenocarcinoma was classified as pathologically invasive group. The statistical differences were assessed by the Mann-Whitney U test or chi-square test. We used two machine learning algorithm. Three logistic regression (LR) models were trained based on sex, total tumor diameter, SUVmax, CEA, and (1) consolidation diameter (LR-Cd), (2) consolidation volume (LR-Cv), (3) consolidation diameter and volume (LD-Cd+Cv). Similarly, three random forest (RF) models were trained (RF-Cd, RF-Cv, RF-Cd+Cv). Patients were split into a training set (n = 76) and test set (n = 19). Model performance was measured area under the curve (AUC), and compared using receiver-operating characteristics curve analysis on the test set. ResultsTwenty-six non-invasive adenocarcinomas and 69 invasive adenocarcinomas were evaluated. The consolidation diameter and volume, and SUVmax of invasive group were significantly greater than those of non-invasive group (p < 0.001). On the test set, AUC of LR-Cd, RF-Cd, LR-Cv, RF-Cv, LR-Cd+Cv and RF-Cd+Cv were 0.687, 0.703,0.628, 0.744, 0.628 and 0.744 respectively. ConclusionsThe pathological invasiveness could be predicted by using machine learning algorithm. Especially, higher AUCs were obtained in RF-Cv and RF-Cd+Cv model. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

A combined analysis of maximum standardized uptake value on FDG-PET, genetic markers, and clinicopathological risk factors in the prognostic stratification of patients with resected oral cavity squamous cell carcinoma.

Clinical outcomes of patients with resected oral cavity squamous cell carcinoma (OCSCC) chiefly depend on the presence of specific clinicopathological risk factors (RFs). Here, we performed a combined analysis of FDG-PET, genetic markers, and clinicopathological RFs in an effort to improve prognostic stratification. We retrospectively reviewed the clinical records of 2036 consecutive patients with first primary OCSCC who underwent surgery between 1996 and 2016. Of them, 345 underwent ultra-deep targeted sequencing (UDTS, between 1996 and 2011) and 168 whole exome sequencing (WES, between 2007 and 2016). Preoperative FDG-PET imaging was performed in 1135 patients from 2001 to 2016. Complete data on FDG-PET, genetic markers, and clinicopathological RFs were available for 327 patients. Using log-ranked tests based on 5-year disease-free survival (DFS), the optimal cutoff points for maximum standardized uptake values (SUV-max) of the primary tumor and neck metastatic nodes were 22.8 and 9.7, respectively. The 5-year DFS rates were as follows: SUVtumor-max ≥ 22.8 or SUVnodal-max ≥ 9.7 (n = 77) versus SUVtumor-max < 22.8 and SUVnodal-max < 9.7 (n = 250), 32%/62%, P < 0.001; positive UDTS or WES gene panel (n = 64) versus negative (n = 263), 25%/62%, P < 0.001; pN3b (n = 165) versus pN1-2 (n = 162), 42%/68%, P < 0.001. On multivariate analyses, SUVtumor-max ≥ 22.8 or SUVnodal-max ≥ 9.7, a positive UDTS/WES gene panel, and pN3b disease were identified as independent prognosticators for 5-year outcomes. Based on these variables, we devised a scoring system that identified four distinct prognostic groups. The 5-year rates for patients with a score from 0 to 3 were as follows: loco-regional control, 80%/67%/47%/24% (P < 0.001); distant metastases, 13%/23%/55%/92% (P < 0.001); DFS, 74%/58%/28%/7% (P < 0.001); and disease-specific survival, 80%/64%/35%/7% (P < 0.001) respectively. The combined assessment of tumor and nodal SUV-max, genetic markers, and pathological node status may refine the prognostic stratification of OCSCC patients.

Lesion-by-lesion correlation between uptake at FDG PET and the Ki67 proliferation index in resected pancreatic neuroendocrine tumors

BackgroundKi67 proliferation index and tumor uptake on 18fluorodeoxyglucose positron-emitting tomography (FDG-PET) could be correlated in pancreatic neuroendocrine tumors (PanNET), but the evaluation of the former is subject to tumor heterogeneity. AimsExplore the correlation between Ki67 and FDG-PET uptake at the lesion scale in PanNET. MethodsWe identified target lesions ≥10 mm in patients operated on for a PanNET and/or associated metastases with preoperative FDG-PET and without neoadjuvant treatment. We assessed the lesion-by-lesion correlation between Ki67 and the tumor-to-liver SUVmax ratio (SUVmax T/L), and between pathological grade (G) and metabolic grade (mG) (mG1, SUVmax T/L ≤ 1, mG2, SUVmax T/L 1–2.3 and mG3, SUVmax T/L > 2.3). ResultsTwenty-one patients underwent pancreatic (n = 12), liver (n = 2) or combined surgery (n = 7). Overall, 36 target lesions (21 primary PanNET, 13 liver metastases and 2 lymph-node metastases) were identified, of median Ki67 4%. Ki67 correlated with SUVmax T/L (r = 0.55, p < 0.001). Median SUVmax T/L was 0.76, 1.41 and 2.67 for lesions G1, G2 and G3, respectively (p = 0.005). Median Ki67 was 1, 4 and 25 for lesions mG1, mG2 and mG3, respectively (p = 0.005). ConclusionsUptake on FDG-PET could predict the pathological grade of PanNET lesions. Hence, FDG-PET could supplement pathological evaluation of tumor biological aggressiveness and could guide the choice of the most relevant lesions to biopsy.