Primary Tumor Metabolic Tumor Volume Research Articles

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 value of initial [ 18 F]FDG PET/computed tomography volumetric and texture analysis-based parameters in patients with head and neck squamous cell carcinoma.

To determine the predictive value of initial [ 18 F]FDG PET/computed tomography (CT) volumetric and radiomics-derived analyses in patients with head and neck squamous cell carcinoma (HNSCC). Forty-six adult patients had pathologically proven HNSCC and underwent pretherapy [ 18 F]FDG PET/CT were enrolled. Semi-quantitative PET-derived volumetric [(maximum standardized uptake value (SUVmax) and mean SUV (SUVmean), total lesion glycolysis (TLG) and metabolic tumor volume (MTV)] and radiomics analyses using LIFEx 6.73.3 software were performed. In the current study group, the receiver operating characteristic curve marked a cutoff point of 21.105 for primary MTV with area under the curve (AUC) of 0.727, sensitivity of 62.5%, and specificity of 86.8% ( P value 0.041) to distinguish responders from non-responders, while no statistically significant primary SUVmean or max or primary TLG cut off points could be determined. It also marked the cutoff point for survival prediction of 10.845 for primary MTV with AUC 0.728, sensitivity of 80%, and specificity of 77.8% ( P value 0.026). A test of the synergistic performance of PET-derived volumetric and textural features significant parameters was conducted in an attempt to develop the most accurate and stable prediction model. Therefore, multivariate logistic regression analysis was performed to detect independent predictors of mortality. With a high specificity of 97.1% and an overall accuracy of 89.1%, the combination of primary tumor MTV and the textural feature gray-level co-occurrence matrix correlation provided the most accurate prediction of mortality ( P value < 0.001). Textural feature indices are a noninvasive method for capturing intra-tumoral heterogeneity. In our study, a PET-derived prediction model was successfully generated with high specificity and accuracy.

The value on SUV-derived parameters assessed on 18F-FDG PET/CT for predicting mediastinal lymph node metastasis in non-small cell lung cancer

PurposeTo explore valuable predictors for mediastinal lymph node metastasis in non-small cell lung cancer (NSCLC) patients, we analyzed the potential roles of standardized uptake value (SUV)-derived parameters from preoperative 18F-FDG PET/CT combined with clinical characteristics.MethodsData from 224 NSCLC patients who underwent preoperative 18F-FDG PET/CT scans in our hospital were collected. Then, a series of clinical parameters including SUV-derived features [SUVmax of mediastinal lymph node and primary-tumor SUVmax, SUVpeak, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG)] were evaluated. The best possible cutoff points for all measuring parameters were calculated using receiver operating characteristic curve (ROC) analysis. Predictive analyses were performed using a Logistic regression model to determine the predictive factors for mediastinal lymph node metastasis in NSCLC and lung adenocarcinoma patients. After multivariate model construction, data of another 100 NSCLC patients were recorded. Then, 224 patients and 100 patients were enrolled to validate the predictive model by the area under the receiver operating characteristic curve (AUC).ResultsThe mediastinal lymph node metastasis rates in 224 patients for model construction and 100 patients for model validation were 24.1% (54/224) and 25% (25/100), respectively. It was found that SUVmax of mediastinal lymph node ≥ 2.49, primary-tumor SUVmax ≥ 4.11, primary-tumor SUVpeak ≥ 2.92, primary-tumor SUVmean ≥ 2.39, primary-tumor MTV ≥ 30.88 cm3, and primary-tumor TLG ≥ 83.53 were more prone to mediastinal lymph node metastasis through univariate logistic regression analyses. The multivariate logistic regression analyses showed that the SUVmax of mediastinal lymph nodes (≥ 2.49: OR 7.215, 95% CI 3.326–15.649), primary-tumor SUVpeak (≥ 2.92: OR 5.717, 95% CI 2.094–15.605), CEA (≥ 3.94 ng/ml: OR 2.467, 95% CI 1.182–5.149), and SCC (< 1.15 ng/ml: OR 4.795, 95% CI 2.019–11.388) were independent predictive factors for lymph node metastasis in the mediastinum. It was found that SUVmax of the mediastinal lymph node (≥ 2.49: OR 8.067, 95% CI 3.193–20.383), primary-tumor SUVpeak (≥ 2.92: OR 9.219, 95% CI 3.096–27.452), and CA19-9 (≥ 16.6 U/ml: OR 3.750, 95% CI 1.485–9.470) were significant predictive factors for mediastinal lymph node metastasis in lung adenocarcinoma patients. The AUCs for the predictive value of the NSCLC multivariate model through internal and external validation were 0.833 (95% CI 0.769- 0.896) and 0.811 (95% CI 0.712–0.911), respectively.ConclusionHigh SUV-derived parameters (SUVmax of mediastinal lymph node and primary-tumor SUVmax, SUVpeak, SUVmean, MTV and TLG) might provide varying degrees of predictive value for mediastinal lymph node metastasis in NSCLC patients. In particular, the SUVmax of mediastinal lymph nodes and primary-tumor SUVpeak could be independently and significantly associated with mediastinal lymph node metastasis in NSCLC and lung adenocarcinoma patients. Internal and external validation confirmed that the pretherapeutic SUVmax of the mediastinal lymph node and primary-tumor SUVpeak combined with serum CEA and SCC can effectively predict mediastinal lymph node metastasis of NSCLC patients.

The Impact of Metabolic 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Parameters on the Prognosis of Resectable Pancreatic Adenocarcinoma.

18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) is a useful staging method in pancreatic cancer. The prognosis of pancreatic adenocarcinoma is affected by the tumor stage and resectable state. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of primary tumors are related to prognostic parameters in pancreatic cancer. This study compared 18F-FDG PET/CT findings with prognostic factors and overall survival of patients with pancreatic cancer. Patients with pancreatic adenocarcinoma, referred to our department between 2015 and 2022 for staging, were retrospectively evaluated. Head-to mid-thigh PET/CT images were obtained 1 h after 18F-FDG injection. Demographic data, survival, and clinical and pathological findings of 39 patients, who underwent surgery after PET/CT imaging, were collected. All primary tumor MTV, SUVmax, background SUVmax, and TLG data have were measured. The images of 39 patients (24 women and 15 men) with a mean age of 66.62±9.60 years were evaluated. The mean SUVmax, MTV 40%, and TLG of the primary tumors in the pancreatic tissue were 6.28±2.33, 19.33±9.77, and 66.56±45.99, respectively. The average survival after disease diagnosis was 18.97±11.47 (2-55) months. MTV and TLG were significantly higher in patients who died during our study. SUVmax has a significant effect on mortality. 18F-FDG PET/CT metabolic parameters of SUVmax, MTV, and TLG could help predicting the prognosis of pancreatic cancer preoperatively and follow-up in patients with resectable tumors. Additionally, in our study group tumor grade and perineural invasion significantly affected overall survival.

Prognostic role of primary tumor metabolic-volumetric parameters of 18F-fluorodeoxyglucose positron emission tomography in tongue squamous cell carcinoma

Aim: It was aimed to evaluate the prognostic role of primary tumor metabolic-volumetric parameters of 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in resectable tongue squamous cell carcinoma (TSCC).&#x0D; Materials and Methods: The imaging findings of 44 TSCC patients (23 females, 21 males, mean age: 58 ± 12) with resectable tumors who underwent 18F-FDG PET/CT imaging for primary staging before surgery between 2010-2021 were evaluated retrospectively. Maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), metabolic tumor volume (MTV) of primary tumors were acquired from PET/CT. Histopathological risk factors (pathological tumor and nodal stage, perineural and lymphovascular invasion, depth of invasion, surgical margin positivity) obtained from surgical resection material of primary tumors were also recorded. The prognostic values of imaging and histopathological parameters were assessed by Cox proportional hazards regression models. Survival curves were estimated by using the Kaplan-Meier analysis.&#x0D; Results: The median follow-up period after diagnosis was 24 months (range: 2-152 months). The univariate and multivariate regression analyses demonstrated that MTV was the only parameter which was significantly related to prognosis for PFS and OS. The patients with higher MTV (&gt; 3.13 cm3) had lower OS and PFS rates compared to those with lower MTV (≤ 3.13 cm3) (p = 0.002, p &lt; 0.001, respectively). &#x0D; Conclusion: Primary tumor MTV is an independent prognostic factor in resectable TSCC. PET volumetric features can be used as prognostic biomarker to predict patients with poor prognosis.

Significance of metabolic tumor volume and total lesion uptake measured using Ga-68 labelled prostate-specific membrane antigen PET/CT in primary staging of prostate cancer.

To evaluate the accuracy of Ga-68 prostate-specific membrane antigen positron-emission-tomography and computed-tomography(PSMA-PET/CT) in primary nodal staging of prostate cancer (PCa), and the predictive value of volumetric parameters derived from Ga-68- PSMA-PET/CT data in lymph node(LN) metastasis and correlation with histopathological and surgical outcomes. Seventy-seven patients with newly diagnosed, biopsy-proven PCa who underwent Ga-68-PSMA-PET/CT for primary staging of disease and underwent radical prostatectomy with extendend pelvic LN dissection were evaluated retrospectively. 2 experienced nuclear medicine specialists have retrospectively reviewed PET/CT images blinded to all histopathological and clinical data. Sensitivity, specificity, positive predictive value(PPV), and negative predictive value(NPV) for the detection of LN metastases were analyzed per-patient. Volumetric and semiquantitative PET parameters of the primary prostate lesions including SUVmax,metabolic tumor volume(MTV), and total lesion uptake(TLU) were measured and recorded. Primary tumor SUVmax, MTV and TLU were found significantly higher in patients who were in higher ISUP Grade groups 3,4,5 after surgical treatment (P = 0.021,P = 0.049,P = 0.032, respectively). The sensitivity, specificity, PPV and NPV on LN metastasis detection of Ga-68-PSMA-PET/CT was found 60%, 91%, 82% and 78% respectively. Although the distribution of the measured primary tumor MTV and TLU values were higher in histopathologically proven LN metastasis positive patients compared to negative patients, only TLU was statistically significant(P = 0.023). Increase in primary tumor TLU values were correlated with higher pT stages and surgical margin positivity(P = 0.034). Ga-68-PSMA-PET/CT is of clinically valuable for primary staging. Measuring and adding these 2 parameters in routine clinical evaluation may increase the prediction power of high-grade disease confirmed by surgery.

Prognostic Value of 18 F-Fluoro-Deoxyglucose-Positron Emission Tomography Volumetric Parameters in Human Papillomavirus-Related Oropharyngeal Squamous Cell Carcinoma.

This study evaluates and compares the prognostic significance of 18 F-fluoro-deoxyglucose-positron emission tomography (18 F-FDG PET) volumetric parameters in human papillomavirus-related oropharyngeal squamous cell carcinoma (OPSCC). A retrospective review of all patients treated for OPSCC with curative intent between 2012 and 2018 was performed. Volumetric parameters analyzed included the maximum standardized uptake value (SUVmax ), SUVpeak , metabolic tumor volume (MTV), and total lesion glycolysis (TLG) in both the primary tumor and nodal metastases. Prognostic significance was determined using Cox proportional hazards models for disease-free survival (DFS) and overall survival (OS). Primary tumor MTV and TLG significantly correlated with both DFS and OS however the commonly reported SUVmax was not found to be predictive. Nodal measures of SUVmax , MTV, and TLG were not significant predictors of survival outcomes. A higher burden of metabolically active primary tumor as measured on volumetric 18 F-FDG PET parameters is associated with poorer DFS and OS. This improved prognostication may be used to counsel patients and select those appropriate for treatment de-escalation in the future. 3 Laryngoscope, 133:1667-1672, 2023.

Investigation of Added Value of Imaging Performed in a Prone Position to Standard 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Imaging for Staging in Patients with Breast Cancer.

Objectives:To investigate whether additional imaging in a prone position has any value to the supine whole-body 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) images by comparing the visual and quantitative data about a local disease in the breast and axilla for the initial staging of breast cancer (BC).Methods:In this study, a total of 91 female patients with the BC were studied. Both the supine and prone images were examined based on the axial diameter, number and location of the primary tumor, local invasion signs of the tumor, the number of axillary lymph nodes with a suspected metastasis, metabolic parameters of the primary tumor and axillary lymph nodes, and registration artifacts of the PET and CT images were evaluated individually. These findings were compared with the histopathological data obtained after a surgery.Results:In the evaluation of a supine and prone imaging, tumor diameter and metabolic tumor volume (MTV) values of the breast lesions were greater in the supine position than in the prone position. However, there was no significant difference found between the other metabolic parameters of a primary tumor and axilla in both positions. In the supine and prone images, accuracy for skin involvement was 84% and 91.3%, respectively.Conclusion:In our study, we observed that, obtaining additional images in the prone position does not significantly benefit the evaluation of a local disease. The average values of the primary tumor diameter and MTV in the prone position appear to be smaller than the one in the supine position. However, the prone imaging in the patients with a newly diagnosed BC may be beneficial in selected patients and may contribute to preventing the false-positive results especially in patients with a suspected skin involvement.

Prognostic Value of Pretherapeutic Primary Tumor MTV from [18F]FDG PET in Radically Treated Cervical Cancer Patients.

The aim of this study was to assess the usefulness of pretherapeutic primary tumor metabolic tumor volume (MTV) in the prognosis of radically treated cervical cancer patients. Retrospective, single-centre analysis was performed on a group of 508 cervical cancer patients. All patients underwent a pretreatment [18F]FDG PET/CT study for the assessment of the disease stage. Several PET-derived parameters—namely, maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), total lesion glycolysis (TLG) and MTV, as well as the clinical parameters, were analysed in terms of the overall survival (OS), event-free survival (EFS), locoregional control (LRC) and freedom from distant metastases (FFDM). Hyperthermia and brachytherapy were prognostic for EFS, OS, and LRC.FIGO stage > II showed a significant effect on EFS, OS, and FFDM. Moreover, hysterectomy was prognostic for OS and histology was prognostic for FFDM. From the PET-derived parameters only MTV of the primary tumor had a significant influence on OS (cutoff point: >12.7 mL, HR: 2.8, 1.75–4.48 95% CI, p < 0.001), LRC (cutoff point: >13.7 mL, HR 2.82, 1.42–5.61 95% CI, p = 0.003), EFS (cutoff point: >10.4 mL, HR: 2.57, 1.67–3.97 95% CI, p < 0.001) and FFDM (cutoff point: >10.4 mL, HR: 5.04, 1.82–13.99 95% CI, p = 0.002). Pretreatment MTV from the primary tumor is the only independent prognostic parameter in OS, LRC, EFS, and FFDM in radically treated cervical cancer patients and should be used in clinical practice in assessing prognosis in these patients.

Predictive Value of Occult Metastasis and Survival Significance of Metabolic Tumor Volume Determined by PET-CT in cT1-2N0 Squamous Cell Carcinoma of the Tongue.

ObjectivesOur goal was to analyze the possibility of using metabolic tumor volume (MTV) to predict occult cervical metastasis and survival in cT1-2N0 squamous cell carcinoma (SCC) of the tongue.MethodsData on the primary tumor MTV and cervical node status as determined by the maximum standardized uptake value were retrieved. The sensitivity and specificity in predicting occult metastasis were calculated with a fourfold table. Associations between occult metastasis and clinicopathological variables were evaluated by univariate and multivariate analyses. The main study endpoints were locoregional control (LRC) and disease-specific survival (DSS).ResultsA total of 24 (20.3%) of 118 patients had occult metastasis. An MTV cutoff value of 4.3 cm3 showed a sensitivity of 50.0% and a specificity of 76.6% in predicting occult metastasis. The sensitivity and specificity of PET-CT in predicting occult metastasis in cT1 tumors were 66.6 and 89.8%, respectively, with values of 83.3 and 67.3%, respectively, when combined with the MTV. The sensitivity and specificity of PET-CT in predicting occult metastasis in cT2 tumors were 72.2 and 82.2%, respectively, with values of 88.9 and 57.8%, respectively, when combined with the MTV. Patients with MTV ≥4.3 cm3 had a higher occult metastasis rate than patients with MTV <4.3 cm3. The 5-year LRC and DSS rates were 86 and 94%, respectively, in patients with MTV <4.3 cm3 and 54 and 72%, respectively, in patients with MTV ≥4.3 cm3. Both differences were found to be significant in univariate and multivariate analyses.ConclusionsMTV ≥4.3 cm3 was associated with an increased probability of occult metastasis and lower LRC and DSS rates in early-stage SCC of the tongue.

Asphericity of tumor FDG uptake in non-small cell lung cancer: reproducibility and implications for harmonization in multicenter studies

BackgroundAsphericity (ASP) of the primary tumor’s metabolic tumor volume (MTV) in FDG-PET/CT is independently predictive for survival in patients with non-small cell lung cancer (NSCLC). However, comparability between PET systems may be limited. Therefore, reproducibility of ASP was evaluated at varying image reconstruction and acquisition times to assess feasibility of ASP assessment in multicenter studies.MethodsThis is a retrospective study of 50 patients with NSCLC (female 20; median age 69 years) undergoing pretherapeutic FDG-PET/CT (median 3.7 MBq/kg; 180 s/bed position). Reconstruction used OSEM with TOF4/16 (iterations 4; subsets 16; in-plane filter 2.0, 6.4 or 9.5 mm), TOF4/8 (4 it; 8 ss; filter 2.0/6.0/9.5 mm), PSF + TOF2/17 (2 it; 17 ss; filter 2.0/7.0/10.0 mm) or Bayesian-penalized likelihood (Q.Clear; beta, 600/1750/4000). Resulting reconstructed spatial resolution (FWHM) was determined from hot sphere inserts of a NEMA IEC phantom. Data with approx. 5-mm FWHM were retrospectively smoothed to achieve 7-mm FWHM. List mode data were rebinned for acquisition times of 120/90/60 s. Threshold-based delineation of primary tumor MTV was followed by evaluation of relative ASP/SUVmax/MTV differences between datasets and resulting proportions of discordantly classified cases.ResultsReconstructed resolution for narrow/medium/wide in-plane filter (or low/medium/high beta) was approx. 5/7/9 mm FWHM. Comparing different pairs of reconstructed resolution between TOF4/8, PSF + TOF2/17, Q.Clear and the reference algorithm TOF4/16, ASP differences was lowest at FWHM of 7 versus 7 mm. Proportions of discordant cases (ASP > 19.5% vs. ≤ 19.5%) were also lowest at 7 mm (TOF4/8, 2%; PSF + TOF2/17, 4%; Q.Clear, 10%). Smoothing of 5-mm data to 7-mm FWHM significantly reduced discordant cases (TOF4/8, 38% reduced to 2%; PSF + TOF2/17, 12% to 4%; Q.Clear, 10% to 6%), resulting in proportions comparable to original 7-mm data. Shorter acquisition time only increased proportions of discordant cases at < 90 s.ConclusionsASP differences were mainly determined by reconstructed spatial resolution, and multicenter studies should aim at comparable FWHM (e.g., 7 mm; determined by in-plane filter width). This reduces discordant cases (high vs. low ASP) to an acceptable proportion for TOF and PSF + TOF of < 5% (Q.Clear: 10%). Data with better resolution (i.e., lower FWHM) could be retrospectively smoothed to the desired FWHM, resulting in a comparable number of discordant cases.

Associations of volumetric whole-body 18F-FDG PET/CT parameters with the CA 19-9 level and haemogram parameters in pancreatic adenocarcinoma.

The present study compared metabolic and volumetric fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) parameters [metabolic tumour volume (MTV), total lesion glycolysis (TLG), and maximum standardized uptake value (SUVmax)] with carbohydrate antigen (CA) 19-9 tumour marker levels and haemogram parameters [(neutrophil-lymphocyte ratio, mean platelet volume (MPV), and platelet-lymphocyte ratio] as prognostic and diagnostic markers of pancreatic cancer. A total of 66 patients who underwent 18F-FDG PET/CT in our nuclear medicine clinic between February 2017 and March 2019, and had a diagnosis of pancreatic adenocarcinoma, were included in this retrospective study. The enrolled patients had not been administered steroids or operated on. Among these patients, whose haemogram parameters and tumour markers could not be assessed by PET/CT within the same week were excluded. The MTV, TLG, and SUVmax values were calculated from primary tumours and metastases in all patients. Spearman's rho correlation, used to examine the relationship between the CA 19-9 level and PET parameters, revealed a statistically significant positive correlation of CA 19-9 with the whole-body MTV (MTVWB) (P<0.001) and whole-body TLG (TLGWB) (P<0.001). Although no significant relationship was found between the neutrophil count and TLGWB according to Spearman's rho correlation, in an artificial neural network using the hidden layer activation function, the neutrophil count showed the strongest association with MTVWB among all included variables. The primary pancreatic tumour MTV and TLG values showed statistically significant positive correlations with the metastases MTV, metastases TLG, MTVWB, and TLGWB values. The CA 19-9 level is considered an important marker of tumour load; it shows a statistically significant positive correlation with parameters such as MTVWB and TLGWB, which provide a measure of the whole-body tumour load. It appears that the MTV and TLG values of the primary pancreatic tumour could also be used as markers of the whole-body tumour load, given their associations with MTVWB and TLGWB.

Metabolic Tumor Volume Change Predicts Long-term Survival and Histological Response to Preoperative Chemotherapy in Locally Advanced Esophageal Cancer.

Here, we assess the ability of metabolic tumor volume (MTV) as measured by F-fluorodeoxyglucose-positron emission tomography/computed tomography (F-FDG PET/CT) to evaluate neoadjuvant chemotherapy response for patients with locally advanced esophageal cancer (EC). Optimal methods to evaluate treatment response for EC patients have not yet been established. Although previous studies have reported the value of standardized uptake value (SUV), the accuracy of predicting histological response or long-term survival in EC is limited. In all, 102 EC patients without distant metastasis who underwent F-FDG PET/CT both before and after the preoperative chemotherapy series were analyzed. The median primary tumor MTV values before and after preoperative chemotherapy were 22.55 (range 0.4-183.1) and 2.75 (0-52.9), respectively, and the median MVT reduction rate was 86.5%. We found the most significant difference in survival between PET responders and nonresponders with a cut-off value of 60% MTV reduction, using a 10% stepwise cut-off analysis [2-year progression-free survival (PFS): 79.2 vs 44.4%; hazard ratio (HR) 3.397; P < 0.0001). With this cut-off value, histological response (P = 0.0091), tumor location (P = 0.0102), pT (P = 0.0011), and pN (P = 0.0110) were significantly associated with PET response. Univariate analysis of PFS indicated a correlation between PFS and tumor size, cT, decrease of primary lesion by CT, SUVmax reduction rate, MTV reduction rate, pT, pN, and pM. Multivariate analysis further identified pM (HR 3.063; P = 0.0279) and MTV reduction rate (HR 2.471; P = 0.0263) to be independent prognostic predictors, but not decrease of primary lesion by CT or SUVmax reduction rate. MTV change is clinically useful in predicting both long-term survival and histological response to preoperative chemotherapy in EC patients, after determining the optimal cut-off value based on survival analysis.

Validation of Independent Prognostic Value of Asphericity of 18F-Fluorodeoxyglucose Uptake in Non–Small-Cell Lung Cancer Patients Undergoing Treatment With Curative Intent

BackgroundIn patients with non–small-cell lung cancer (NSCLC), asphericity (ASP) of the primary tumor’s metabolic tumor volume (MTV) has shown prognostic significance. This study aimed at validation in an independent and sufficiently large cohort. Patients and MethodsA retrospective study was performed of 311 NSCLC patients undergoing 18F-fluorodeoxyglucose positron emission tomography / computed tomography (18F-FDG PET/CT) before curatively intended treatment (always including surgery). A total of 140 patients had International Union Against Cancer (UICC) stage I disease, 78 had stage II disease, and 93 had stage III disease (adenocarcinoma, n = 153; squamous-cell carcinoma, n = 141). Primary tumor MTV was delineated with semiautomated background-adapted threshold relative to the standardized maximum uptake value (SUVmax). Cox regression (progression-free survival [PFS] and overall survival [OS]) analysis for positron emission tomography (MTV, ASP, SUVmax) as well as for clinical (T/N descriptor, UICC stages), histologic, and treatment variables (Rx/1 vs. R0 resection, chemotherapy/radiotherapy yes/no) were performed. ResultsEvents (progression and relapse) occurred in 167 of 311 patients; 137 died (median survivor follow-up, 37 months). In multivariable Cox regression for OS, ASP > 33.3% (hazard ratio, 1.58 [1.04-2.39]), male sex (1.84), age (1.04 per year), Eastern Cooperative Oncology Group performance status ≥ 2 versus 0/1 (2.68), stage II versus I (1.96), and Rx/1 versus R0 resection (2.1) were significant. Among separate UICC stages, ASP only predicted OS in stage II (optimal, > 19.5%; median OS, 33 vs. 59 months). Regarding PFS, ASP > 21.2%, male sex, Eastern Cooperative Oncology Group performance status ≥ 2, stage II versus I disease, and Rx/1 resection were prognostic. ASP remained prognostic for stage II disease (optimal, > 19.5%; PFS, 12 vs. 47 months). Log-rank test for ASP was significant at any cutoff ≥ 18% (OS) or from 9% to 59% (PFS). ConclusionASP was validated as prognostic factor for PFS and OS in patients with NSCLC and curative treatment intent, especially stage II. High ASP in stage II could imply intensified treatment or intensified follow-up.

Total metabolic tumor volume by 18F-FDG PET/CT for the prediction of outcome in patients with non-small cell lung cancer.

Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are imaging parameters derived from 18F-FDG PET/CT that have been proposed for risk stratification of cancer patients. The aim of our study was to test whether these whole-body volumetric imaging parameters may predict outcome in patients with non-small cell lung cancer (NSCLC). Sixty-five patients (45 men, 20 women; mean age ± SD, 65 ± 12years), with histologically proven NSCLC who had undergone 18F-FDG PET/CT scan before any therapy, were included in the study. Imaging parameters including SUVmax, SUVmean, total MTV (MTVTOT) and whole-body TLG (TLGWB) were determined. Univariate and multivariate analyses of clinical and imaging variables were performed using Cox proportional hazards regression. Survival analysis was performed using Kaplan-Meier method and log-rank tests. A total of 298 lesions were analyzed including 65 primary tumors, 114 metastatic lymph nodes and 119 distant metastases. MTVTOT and TLGWB could be determined in 276 lesions. Mean value of MTVTOT was 81.83ml ± 14.63ml (SE) whereas mean value of TLGWB was 459.88g ± 77.02g (SE). Univariate analysis showed that, among the variables tested, primary tumor diameter (p = 0.0470), MTV of primary tumor (p = 0.0299), stage (p < 0.0001), treatment (p < 0.0001), MTVTOT (p = 0.0003) and TLGWB (p = 0.0002) predicted progression-free survival in NSCLC patients, while age (p = 0.0550), MTV of primary tumor (p = 0.0375), stage (p < 0.0001), treatment (p < 0.0001), MTVTOT (p = 0.0001) and TLGWB (p = 0.0008) predicted overall survival. At multivariate analysis age, TLGWB and stage were retained in the model for prediction of progression-free survival (p < 0.0001), while age, MTVTOT and stage were retained in the model for prediction of overall survival (p < 0.0001). Survival analysis showed that patients with TLGWB ≤ 54.7g had a significantly prolonged progression-free survival as compared to patients with TLGWB > 54.7g (p < 0.0001). Moreover, overall survival was significantly better in patients showing a MTVTOT ≤ 9.5ml as compared to those having MTVTOT > 9.5ml (p < 0.0001). Similar results were obtained in a subgroup of 43 patients with advanced disease (stages III and IV). Whole-body PET-based volumetric imaging parameters are able to predict outcome in NSCLC patients.

1866P - Clinical utility of metabolic tumor volume in papillary thyroid carcinoma

BackgroundThe management of papillary thyroid carcinoma (PTC) should be decided by Risk-adapted approach. However, intermediated risk PTC needs to be stratified more precisely. Otherwise, the utility of 18F-FDG PET images in patients with PTC is restrictive. The aim of this study was to investigate the prognostic value of Metabolic Tumor Volume (MTV) measured on 18F-FDG PET images in patients with papillary thyroid carcinoma treated with surgery. MethodsWe retrospectively analyzed 102 patients with PTC who underwent 18F-FDG PET/CT between Feburary 2009 and June 2017 at Osaka University Medical School Hospital for initial staging before surgery. We evaluated the association of MTV of primary tumor (T-MTV) with relapse-free survival (RFS) using Cox regression analysis. Receiver operating characteristic (ROC) curves were used to estimate the optimal cut-off values for T-MTV. We also conducted recursive partitioning analyses to offer a novel risk stratification system. ResultsThe 3-year RFS for all patients were 81.2% with median follow-up of 42 months (range 11-111). In Cox model, T-MTV (Hazard Ratio, 1.23; 95% CI, 1.08 to 1.38; P=0.002) was significantly associated with RFS. ROC analyses showed that the optimal cutoff value of T-MTV was 10.3ml. We classified the patients as having a low, intermediate, or high risk of relapse or death on the basis of T-MTV and lymph node metastasis. ConclusionsMTV of primary tumor was a significant prognostic factor for RFS in patients with PTC treated with surgery. Incorporation of T-MTV into staging may lead to a better risk stratification. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Metabolic tumor volume and conformal radiotherapy based on prognostic PET/CT for treatment of nasopharyngeal carcinoma.

For patients with nasopharyngeal carcinoma (NPC), prognostic indicators to customize subsequent biologically conformal radiation therapy may be obtained via 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). This retrospective study assessed the prognostic significance and feasibility of conformal radiotherapy for NPC, based on 18F-FDG PET/CT. Eighty-two patients with NPC underwent 18F-FDG PET/CT prior to intensity-modulated radiation therapy (IMRT). The maximum standardized uptake value (SUVmax) and metabolic tumor volume (MTV) of the primary tumor were measured, with MTVx based on absolute SUVx values ≥ specific threshold x on each axial image. The cut-off SUVmax and MTV values for predicting 3-year progression-free survival (PFS) were calculated according to a receiver operating characteristic curve. Assessed were correlations between SUVmax and MTV and between threshold x and MTVx, and the MTV percentage of the primary tumor volume at threshold x. The SUVmax and MTV were positively associated, as were MTV and primary tumor volume. Primary tumor volume, SUVmax, and MTV were significant predictors of survival. The 3-year PFS rates for SUVmax ≤8.20 and >8.20 were 91.1% and 73.0%, respectively (P = .027). With furthermore analysis, patients having tumor with smaller MTV had higher 3-year PFS than patients having tumor with larger MTV. The 3-year PFS rate was inversely related to MTV. SUVmax and MTV, derived by PET/CT, are important for assessing prognosis and planning radiotherapy for patients with NPC. Small MTV indicated better 3-year PFS compared with large MTV. For the best therapeutic effect, MTV4.0 was the best subvolume to determine radiotherapy boost.

The prognostic value of preoperative FDG-PET/CT metabolic parameters in cervical cancer patients

BackgroundTo explore quantitative metabolic and microstructural primary tumour parameters at pretreatment FDG-PET/CT and diffusion-weighted-magnetic resonance imaging (DW-MRI) in relation to clinical FIGO stage and outcome in uterine cervical cancer patients.MethodsFifty three patients with histopathologically verified cervical carcinoma with clinical FIGO stage IB1-IVA were subjected to FDG-PET/CT and subgroup also DW-MRI (n = 30) prior to treatment. Measurements from the FDG-PET/CT comprised lesion maximum-standardised uptake value (SUVmax), total lesion glycolysis (TLG) and metabolic tumour volume (MTV). In MR images longest-tumour-diameter (MRI-LD), tumour volume (MRI-TV) and mean tumour apparent-diffusion-coefficient (ADCmean) value were measured. FDG-PET/CT parameters were explored in relation to clinical prognostic factors at diagnosis and progression/recurrence free survival, and compared with the MRI parameters.ResultsThe metabolic tumour parameters TLG and MTV were highly positively correlated to MRI-LD and MRI-TV (rs = 072–0.82; p < 0.001 for all), whereas tumour SUVmax was only moderately correlated to MRI-LD (rs = 0.29; p ≤ 0.04) and MRI-TV (rs = 0.36; p ≤ 0.01). High tumour TLG, MTV, MRI-LD and MRI-TV predicted advanced FIGO stage, whereas high tumour SUVmax did not. No significant correlations were observed between tumour ADCmean and the other imaging parameters or FIGO stage. High primary tumour MTV (≥56.7 mL), high TLG (≥412 g) and large MRI-TV (≥36 mL) predicted reduced progression/recurrence free survival yielding corresponding hazard ratios [HR] of 7.8 (P = 0.002), 6.9 (P = 0.004) and 4.6 (P = 0.022), respectively. Also advanced FIGO stage (≥IIIA) was associated with reduced progression/recurrence free survival with HR of 6.9 (P = 0.004). In multivariable analysis, advanced FIGO stage (≥IIIA) and high MTV (≥56.7 mL) were independent prognostic factors with adjusted HRs of 5.5 (P = 0.020) and 7.8 (P = 0.025), respectively.ConclusionHigh MTV at pre-treatment FDG-PET/CT and high clinical FIGO stage independently predict reduced progression/recurrence free survival in cervical cancer patients.

PET-based prognostic survival model after radiotherapy for head and neck cancer.

The aims of this multicentre retrospective study of locally advanced head and neck cancer (LAHNC) treated with definitive radiotherapy were to (1) identify positron emission tomography (PET)-18F-fluorodeoxyglucose (18F-FDG) parameters correlated with overall survival (OS) in a training cohort, (2) compute a prognostic model, and (3) externally validate this model in an independent cohort. A total of 237 consecutive LAHNC patients divided into training (n = 127) and validation cohorts (n = 110) were retrospectively analysed. The following PET parameters were analysed: SUVMax, metabolic tumour volume (MTV), total lesion glycolysis (TLG), and SUVMean for the primary tumour and lymph nodes using a relative SUVMax threshold or an absolute SUV threshold. Cox analyses were performed on OS in the training cohort. The c-index was used to identify the highly prognostic parameters. A prognostic model was subsequently identified, and a nomogram was generated. The model was externally tested in the validation cohort. In univariate analysis, the significant PET parameters for the primary tumour included MTV (relative thresholds from 6 to 83% and absolute thresholds from 1.5 to 6.5) and TLG (relative thresholds from 1 to 82% and absolute thresholds from 0.5 to 4.5). For the lymph nodes, the significant parameters included MTV and TLG regardless of the threshold value. In multivariate analysis, tumour site, p16 status, MTV35% of the primary tumour, and MTV44% of the lymph nodes were independent predictors of OS. Based on these four parameters, a prognostic model was identified with a c-index of 0.72. The corresponding nomogram was generated. This prognostic model was externally validated, achieving a c-index of 0.66. A prognostic model of OS based on primary tumour and lymph node MTV, tumour site, and p16 status was proposed and validated. The corresponding nomogram may be used to tailor individualized treatment.

Tumor response to neoadjuvant chemotherapy in patients with esophageal cancer assessed with CT and FDG-PET/CT – RECIST 1.1 vs. PERCIST 1.0

PurposeWe compared the response classification systems Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST) 1.0 for assessment of response to neoadjuvant chemotherapy in patients with esophageal cancer. Materials and methodsPrior to planned surgical resection, 62 patients with esophageal cancer underwent fluorodeoxyglucose (FDG)-PET/CT and contrast-enhanced CT examinations before and after receiving neoadjuvant chemotherapy. Primary tumor largest diameter, maximum standardized uptake value (SUVmax), peak lean body mass SUV (SULpeak), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were determined. Patients were divided into responders (grade 1b-3) and non-responders (grade 0-1a) according to pathological response. ResultsConcordance between RECIST 1.1 and PERCIST 1.0 for response classification was seen in 28 (45.2%) patients. For 18 defined as responders, the number of metabolic responders (partial metabolic response + complete metabolic response) shown by PERCIST 1.0 was 17 and the number of anatomic responders (partial response + complete response) shown by RECIST 1.1 was 13. To distinguish responders from non-responders, the area under the receiver operating characteristics curve values for reduced primary tumor largest diameter, SUVmax, SULpeak, MTV, and TLG were 0.724, 0.775, 0.781, 0.756, and 0.759, respectively. An optimal percent decrease in largest diameter cut-off value of 39.2% was found to have 66.7% sensitivity and 70.5% specificity, while that for SULpeak of 55.8% was 77.8% and 75.0%, respectively. ConclusionsAs compared to RECIST 1.1, PERSIST 1.0 may be more suitable for evaluation of neoadjuvant therapeutic response to esophageal cancer.