Analysis of pretreatment FDG-PET SUV parameters in head-and-neck cancer: tumor SUVmean has superior prognostic value

Performance of 18F-FDG PET/MRI and its parameters in staging and neoadjuvant therapy response evaluation in bladder cancer

18F-FDG PET/MRI shows potential efficacy in the diagnosis of bladder cancer (BLCA). However, the performance of 18F-FDG PET/MRI in staging and neoadjuvant therapy (NAT) response evaluation for BLCA patients remains elusive. Here, we conduct this study to evaluate the performance of 18F-FDG PET/MRI and its derived parameters for tumor staging and NAT response prediction in BLCA. Forty BLCA patients were retrospectively enrolled to evaluate the performance of 18F-FDG PET/MRI in staging and NAT response prediction in BLCA. The feasibility of using 18F-FDG PET/MRI-related parameters for tumor staging and NAT response evaluation was also analyzed. In conclusion, 18F-FDG PET/MRI is found to show good performance in the BLCA staging and NAT response prediction. Moreover, ΔSUVmean is an efficacious candidate parameter for NAT response prediction. This study highlights that 18F-FDG PET/MRI is a promising imaging approach in the clinical diagnosis and treatment for BLCA.

Quantitation of Oncologic Image Features for Radiomic Analyses in PET

Radiomics is an emerging and exciting field of study involving the extraction of many quantitative features from radiographic images. Positron emission tomography (PET) images are used in cancer diagnosis and staging. Utilizing radiomics on PET images can better quantify the spatial relationships between image voxels and generate more consistent and accurate results for diagnosis, prognosis, treatment, etc. This chapter gives the general steps a researcher would take to extract PET radiomic features from medical images and properly develop models to implement.

[Metabolic Tumor Imaging in Head and Neck Oncology]

Metabolic Tumor Imaging in Head and Neck Oncology Abstract. Fluorodeoxyglucose with position emission tomography combined with CT or MRI (FDG-PET) has become an important diagnostic and staging method in head and neck squamous cell carcinoma. Some regard FDG-PET merely as a tool able of displaying cancer cells as bright spots on imaging. However, quantification of FDG uptake can be used as a surrogate marker for tumor aggressiveness and predict tumor response before (chemo)-radiation. The FDG uptake of the primary tumor can also predict surgical outcome measures such as depth of invasion, occult nodal metastasis, or bone invasion for oral cancer and/or organ preservation in hypopharyngeal cancer.

Prognostic significance of conventional and volumetric PET parameters with and without partial volume correction in the assessment of head and neck squamous cell carcinoma

BACKGROUND

The optimal quantification of PET in assessment of head and neck squamous cell carcinoma (HNSCC) is still under development. The effect of partial volume correction (PVC) on the evaluation of survival in the HNSCC patients has not been investigated yet.

METHODOLOGY

Pretreatment 18F-FDG-PET/CT scans of a selected group of 57 patients with advanced stage HNSCC were collected. Conventional (SUVmean and SUVmax) and volumetric [total lesion glycolysis (TLG) and metabolic tumor volume (MTV)] PET metrics were calculated. The ROVER software (ABX GmbH, Radeberg, Germany) automatically applied PVC to the PET metrics. Cox proportional hazards regression model calculated hazard ratio (HR) for assessment of predictive parameters of progression-free survival (PFS).

RESULTS

In multivariate Cox regression analysis, including age, gender, race, human papillomavirus status, and stage, the only significant predictors of PFS were the volumetric PET parameters (TLG: HR, 1.003; 95% CI, 1.001-1.005; P = 0.02), pvcTLG (HR, 1.002; 95% CI, 1.001-1.004; P = 0.01) and MTV (HR, 1.050; 95% CI, 1.024-1.077; P < 0.01). The partial volume-corrected values were significantly higher than the noncorrected values (Wilcoxon sign test; P < 0.05). However, there was not a statistically significant difference between the nonpartial volume corrected and partial volume-corrected PET metrics for assessment of PFS.

CONCLUSION

Volumetric PET metrics were predictors of PFS in Cox regression analysis. Applying PVC could not significantly improve the accuracy of PET metrics for assessment of PFS.

Prognostic significance of metabolic tumour volume and maximum standard uptake value of fluor-18-fluorodeoxyglucose positron emission tomography with computed tomography in nasopharyngeal carcinoma

Aim of the study

To evaluate the prognostic role of markers of fluor-18-fluorodeoxyglucose positron emission tomography with computed tomography (¹⁸F-FDG-PET-CT), such as maximum standard uptake value (SUV_max) and metabolic tumour volume (MTV) measured at primary and nodal disease, and their clinical significance in terms of predicting treatment outcomes and survival.

Material and methods

Between January 2017 and January 2020, 20 case records of nasopharyngeal carcinoma patients who underwent ¹⁸F-FDG-PET-CT as part of staging workup before radiotherapy and as a part of response evaluation after radiotherapy were retrospectively reviewed.

Results

At a median follow-up of 34.7 months, the 2-year progression-free survival (PFS) was 70% and 2-year overall survival (OS) was 79%. Patients with a lower nodal SUV_max (SUV_max-N) had a better 2-year PFS (91% vs. 46%; p = 0.035) and 2-year OS (95% vs. 58%; p = 0.015). A high SUV_max-N of > 10.58 was a negative predictor of OS (95% confidence interval [CI]: 0.93-1; p = 0.003) as well as PFS (95% CI: 0.64-1; p = 0.017). Also, a high MTV > 25.8 cm³ was a negative predictor of PFS (95% CI: 0.58-0.98; p = 0.048). MTV was an independent predictor of PFS and OS on univariate analysis, whereas it was not significant in the Cox regression multivariate analysis.

Conclusions

High values of MTV and SUV_max-N can be considered as independent prognostic factors of OS and PFS in nasopharyngeal cancer patients treated with concurrent chemoradiation, highlighting the need for more intensified treatment.

Prediction of the local treatment outcome in patients with oropharyngeal squamous cell carcinoma using deep learning analysis of pretreatment FDG-PET images

Background

This study aimed to assess the utility of deep learning analysis using pretreatment FDG-PET images to predict local treatment outcome in oropharyngeal squamous cell carcinoma (OPSCC) patients.

Methods

One hundred fifty-four OPSCC patients who received pretreatment FDG-PET were included and divided into training (n = 102) and test (n = 52) sets. The diagnosis of local failure and local progression-free survival (PFS) rates were obtained from patient medical records. In deep learning analyses, axial and coronal images were assessed by three different architectures (AlexNet, GoogLeNET, and ResNet). In the training set, FDG-PET images were analyzed after the data augmentation process for the diagnostic model creation. A multivariate clinical model was also created using a binomial logistic regression model from a patient’s clinical characteristics. The test data set was subsequently analyzed for confirmation of diagnostic accuracy. Assessment of local PFS rates was also performed.

Results

Training sessions were successfully performed with an accuracy of 74–89%. ROC curve analyses revealed an AUC of 0.61–0.85 by the deep learning model in the test set, whereas it was 0.62 by T-stage, 0.59 by clinical stage, and 0.74 by a multivariate clinical model. The highest AUC (0.85) was obtained with deep learning analysis of ResNet architecture. Cox proportional hazards regression analysis revealed deep learning-based classification by a multivariate clinical model (P < .05), and ResNet (P < .001) was a significant predictor of the treatment outcome. In the Kaplan-Meier analysis, the deep learning-based classification divided the patient’s local PFS rate better than the T-stage, clinical stage, and a multivariate clinical model.

Conclusions

Deep learning-based diagnostic model with FDG-PET images indicated its possibility to predict local treatment outcomes in OPSCCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08599-6.

Differences among [18F]FDG PET-derived parameters in lung cancer produced by three software packages

Investigation of differences in derived [18F]FDG PET metabolic and volumetric parameters among three different software programs in lung cancer. A retrospective analysis was performed on a group of 98 lung cancer patients who underwent a baseline [18F]FDG PET/CT study. To assess appropriate delineation methods, the NEMA phantom study was first performed using the following software: Philips EBW (Extended Brilliance Workstation), MIM Software and Rover. Based on this study, the best cut-off methods (dependent on tumour size) were selected, extracted and applied for lung cancer delineation. Several semiquantitative [18F]FDG parameters (SUVmax, SUVmean, TLG and MTV) were assessed and compared among the three software programs. The parameters were assessed based on body weight (BW), lean body mass (LBM) and Bq/mL. Statistically significant differences were found in SUVmean (LBM) between MIM Software and Rover (4.62 ± 2.15 vs 4.84 ± 1.20; p < 0.005), in SUVmean (Bq/mL) between Rover and Philips EBW (21,852.30 ± 21,821.23 vs 19,274.81 ± 13,340.28; p < 0.005) and Rover and MIM Software (21,852.30 ± 21,821.23 vs 19,399.40 ± 10,051.30; p < 0.005), and in MTV between MIM Software and Philips EBW (19.87 ± 25.83 vs 78.82 ± 228.00; p = 0.0489). This study showed statistically significant differences in the estimation of semiquantitative parameters using three independent image analysis tools. These findings are important for performing further diagnostic and treatment procedures in lung cancer patients.

Analysis of PET parameters as prognosticators of survival and tumor extent in Oropharyngeal Cancer treated with surgery and postoperative radiotherapy

BACKGROUND

Positron-emission tomography (PET) is widely used to detect malignancies, but consensus on its prognostic value in oropharyngeal cancer has not been established. The purpose of this study was to analyze the PET parameters associated with tumor extent and survival in resectable oropharyngeal cancer.

METHODS

The PET parameters in oropharyngeal cancer patients with regional node metastasis who underwent surgery and postoperative radiotherapy between January 2005 and January 2019 were analyzed. We calculated the SUVmax, tumor-to-liver ratio (TLR), metabolic tumor volume (MTV, volume over SUV 2.5), and total lesion glycolysis (TLG, MTV x mean SUV) of the primary lesion and metastatic nodes. Histologic findings, patient survival, and recurrence were reviewed in the medical records.

RESULTS

Fifty patients were included, and the PET parameters were extracted for 50 primary lesions and 104 nodal lesions. In the survival analysis, MTV and TLG of the primary lesions showed significant differences in overall survival (OS) and recurrence-free survival (RFS). In the multiple regression analysis, TLG of the primary lesion was associated with the depth of invasion (DOI). MTV of the nodes was a significant factor affecting extranodal extension (ENE).

CONCLUSIONS

PET parameters could be related with OS, RFS, DOI of the primary tumor, and ENE. PET would be expected to be a useful diagnostic tool as a prognosticator of survival and pathologic findings in oropharyngeal cancer.

18F-FDG-PET/CT in laryngeal cancer: Comparison with conventional imaging and prognostic role

OBJECTIVE

The aim of this study was to investigate the diagnostic accuracy of staging ¹⁸F-FDG-PET/CT in laryngeal cancer, compare these results with conventional imaging (CI) and assess the value of ¹⁸F-FDG-PET/CT features to predict survival.

METHODS

Fifty-four patients with laryngeal squamous cell cancer and baseline ¹⁸F-FDG-PET/CT were retrospectively enrolled. The PET images were analyzed visually and semi-quantitatively by measuring several metabolic parameters. A combination of clinical follow-up/imaging follow-up and/or histopathology was taken as reference standard. Progression free survival (PFS) and disease specific survival (DSS) were computed using Kaplan-Meier curves.

RESULTS

All primary tumors were clearly identified by CI, and 52/54 by ¹⁸F-FDG-PET/CT with a sensitivity of 96.3%. Cervical nodal metastases were detected in 40/54 patients at ¹⁸F-FDG-PET/CT and in 34/49 patients at CI. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy on a patient-based analysis for nodal disease were 100%, 85.7%, 94.6%, 100% and 95.9% at ¹⁸F-FDG-PET/CT, and 91.4%, 85.7%, 94.1%, 80%, 89.8% at CI. Diagnostic performances of PET/CT and CI were not significantly different on a patient-based, side-by-side and level-by-level analysis. ¹⁸F-FDG-PET/CT recognized distant metastases in 7 patients allowing to an upstaging. At a median follow-up of 27 months, relapse/progression of disease occurred in 31 patients and death occurred in 32. Metabolic tumor volume (MTV T), MTV total and total lesion glycolysis (TLG) showed to be independent prognostic factors for PFS.

CONCLUSIONS

Both CI and PET/CT had good diagnostic performances for the staging of laryngeal cancer; baseline metabolic features (MTV and TLG) showed an important prognostic value in assessing the rate of PFS.

Mucormycosis originated total maxillary and cranial base osteonecrosis: a possible misdiagnosis to malignancy

Background

This is a case of mucormycosis originated osteonecrosis of the maxilla extended to the cranial base, initially suspected of malignancy. The patient was first suspected with osteolytic sarcomatous lesion but was later diagnosed with total maxillary necrosis and cranial base through biopsy-proven invasive mucormycosis.

Case presentation

A 71-year-old male was presented with unknown total maxillary osteonecrosis. CT and MRI results showed extensive osteolytic change with bone destruction of the cranial base, and PET-CT showed irregular hypermetabolic lesion in the area suspected of malignancy. The first biopsy results only presented tissue inflammation. Thus, several further endoscopic biopsy were performed through posterior pharyngeal wall. The patient was eventually diagnosed with mucormycosis and associated osteomyelitis with subsequent bone necrosis. With confirmed diagnosis, partial maxillectomy of the necrosed bone was performed under general anesthesia. At the 4 week follow-up, the patient showed full mucosal healing and no recurrence or aggravation of the maxilla and cranial base lesion was observed.

Conclusions

Accurate diagnosis of atypical symptoms, timely diagnosis, and proper combination therapy of surgical intervention, antifungal agent, and antibiotic use for skull base osteomyelitis are all critical for proper treatment planning. In addition, biopsy and CT scans are essential in differentiating osteonecrosis from malignancy.

Total lesion glycolysis in oral squamous cell carcinoma as a biomarker derived from pre-operative FDG PET/CT outperforms established prognostic factors in a newly developed multivariate prediction model

PURPOSE

Retrospective study to investigate the impact of image derived biomarkers from [¹⁸F]FDG PET/CT prior to surgical resection in patients with initial diagnosis of oral squamous cell carcinoma (OSCC), namely SUV_max, SUV_mean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary tumor to predict overall survival (OS).

MATERIALS AND METHODS

127 subsequent patients with biopsy-proven OSCC were included who underwent [¹⁸F]FDG PET/CT before surgery. SUV_max, SUV_mean, MTV and TLG of the primary tumor were measured. OS was estimated according to Kaplan-Meier and compared between median-splitted groups by the log-rank test. Prognostic parameters were analyzed by uni-/multivariate Cox-regression.

RESULTS

During follow-up 52 (41%) of the patients died. Median OS was longer for patients with lower MTV or lower TLG. SUV_max and SUV_mean failed to be significant predictors for OS. Univariate Cox-regression identified MTV, TLG, lymph node status and UICC stage as prognostic factors. By multivariate Cox-regression MTV and TLG turned out to be independent prognostic factors for OS.

CONCLUSIONS

The pre-therapeutic [¹⁸F]FDG PET/CT parameters MTV and TLG in the primary tumor are prognostic for OS of patients with an initial diagnosis of OSCC. TLG is the strongest independent prognostic factor for OS and outperforms established prognostic parameters in OSCC.

Multiple Testing, Cut-Point Optimization, and Signs of Publication Bias in Prognostic FDG-PET Imaging Studies of Head and Neck and Lung Cancer: A Review and Meta-Analysis

Positron emission tomography (PET) imaging with 2-deoxy-2-[¹⁸F]-fluorodeoxyglucose (FDG) was proposed as prognostic marker in radiotherapy. Various uptake metrics and cut points were used, potentially leading to inflated effect estimates. Here, we performed a meta-analysis and systematic review of the prognostic value of pretreatment FDG–PET in head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC), with tests for publication bias. Hazard ratio (HR) for overall survival (OS), disease free survival (DFS), and local control was extracted or derived from the 57 studies included. Test for publication bias was performed, and the number of statistical tests and cut-point optimizations were registered. Eggers regression related to correlation of SUVmax with OS/DFS yielded p = 0.08/p = 0.02 for HNSCC and p < 0.001/p = 0.014 for NSCLC. No outcomes showed significant correlation with SUVmax, when adjusting for publication bias effect, whereas all four showed a correlation in the conventional meta-analysis. The number of statistical tests and cut points were high with no indication of improvement over time. Our analysis showed significant evidence of publication bias leading to inflated estimates of the prognostic value of SUVmax. We suggest that improved management of these complexities, including predefined statistical analysis plans, are critical for a reliable assessment of FDG–PET.

Functional Imaging to Predict Treatment Response in Head and Neck Cancer: How Close are We to Biologically Adaptive Radiotherapy?

It is increasingly recognised that head and neck cancer represents a spectrum of disease with a differential response to standard treatments. Although prognostic factors are well established, they do not reliably predict response. The ability to predict response early during radiotherapy would allow adaptation of treatment: intensifying treatment for those not responding adequately or de-intensifying remaining therapy for those likely to achieve a complete response. Functional imaging offers such an opportunity. Changes in parameters obtained with functional magnetic resonance imaging or positron emission tomography-computed tomography during treatment have been found to be predictive of disease control in head and neck cancer. Although many questions remain unanswered regarding the optimal implementation of these techniques, current, maturing and future studies may provide the much-needed homogeneous cohorts with larger sample sizes and external validation of parameters. With a stepwise and collaborative approach, we may be able to develop imaging biomarkers that allow us to deliver personalised, biologically adaptive radiotherapy for head and neck cancer.

Preoperative 18F-FDG PET/computed tomography predicts survival following resection for colorectal liver metastases

OBJECTIVE

The liver is the most frequent metastatic site from colorectal cancer and about 20% of these patients are treated by surgical resection. However, the 5-year disease-free survival (DFS) following resection is only about 25% and 5-year overall survival (OS) about 38%. The aim of the study was to evaluate the ability of metabolic and volumetric measurements from fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) prior to resection for colorectal liver metastases (CLM) to predict survival.

PATIENTS AND METHODS

Preoperative F-FDG PET/CT examinations were assessed. Metabolic tumor volume (MTV), total lesion glycolysis (TLG), maximum, mean and peak standardized uptake values and tumor to background ratio, were obtained for all CLM. Cutoff values were determined for each of these parameters by using receiver operating characteristic analysis dividing the patients into two groups. DFS, liver recurrence-free survival (LRFS), OS and cancer-specific survival (CSS) for patients over and under the cutoff value were compared by using the Kaplan-Meier method and log-rank test.

RESULTS

Twenty-seven patients who underwent F-FDG PET/CT prior to resection for CLM were included. Low values of total MTV and TLG were significantly correlated to improved 5-year LRFS (P = 0.016 and 0.006) and CSS (P = 0.034 and 0.008). Patients who developed liver recurrence had significantly higher total MTV and TLG compared to patients without liver recurrence (P = 0.042 and 0.047).

CONCLUSION

Low values of total MTV and TLG were significantly correlated to improved LRFS and CSS and may improve the risk stratification of patients considered for resection for CLM.

Histometabolic Tumor Imaging of Hypoxia in Oral Cancer: Clinicopathological Correlation for Prediction of an Aggressive Phenotype

Introduction

Fluorodeoxyglucose-positron emission tomography (FDG-PET) is a widely used imaging tool for oral squamous cell carcinoma (OSCC). Preliminary studies indicate that quantification of tumor metabolic uptake may correlate with tumor hypoxia and aggressive phenotypes.

Methods

Retrospective review of a consecutive cohort of OSCC (n = 98) with available pretherapeutic FDG-PET/CT, treated at the University Hospital Zurich. Clinico-pathologico-radiological correlation between maximum standard uptake value (SUV_max) of the primary tumor, immunohistochemical staining for hypoxia-related proteins glucose transporter 1 (GLUT1) and hypoxia-inducible factor 1-alpha (HIF1a), depth of invasion (DOI), lymph node metastasis, and outcome was examined.

Results

Positive staining for GLUT1 and HIF1a on immunohistopathological analysis correlated with increased SUV_max on pretherapeutic imaging and with increased DOI (Kruskal–Wallis, P = 0.037, and P = 0.008, respectively). SUV_max and DOI showed a strong positive correlation (Spearman Rho, correlation coefficient = 0.451, P = 0.0003). An increase in SUV_max predicted nodal metastasis (Kruskal–Wallis, P = 0.017) and poor local control (log rank, P = 0.047).

Conclusion

In OSCC, FDG-PET-derived metabolic tumor parameter SUV_max serves as a surrogate marker for hypoxia and can be used to predict tumor aggressiveness, with more invasive phenotypes and poorer local control.

18F-FDG-PET/CT in laryngeal cancer: comparison with conventional imaging and prognostic role

OBJECTIVE

The aim of this study was to investigate the diagnostic accuracy of staging 18 F-FDG-PET/CT in laryngeal cancer, compare these results with conventional imaging (CI) and assess the value of 18 F-FDG-PET/CT features to predict survival.

METHODS

Fifty-four patients with laryngeal squamous cell cancer and baseline 18 F-FDG-PET/CT were retrospectively enrolled. The PET images were analyzed visually and semi-quantitatively by measuring several metabolic parameters. A combination of clinical follow-up/imaging follow-up and/or histopathology was taken as reference standard. Progression free survival (PFS) and disease specific survival (DSS) were computed using Kaplan-Meier curves.

RESULTS

All primary tumors were clearly identified by CI, and 52/54 by 18 F-FDG-PET/CT with a sensitivity of 96.3%. Cervical nodal metastases were detected in 40/54 patients at 18 F-FDG-PET/CT and in 34/49 patients at CI. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy on a patient-based analysis for nodal disease were 100%, 85.7%, 94.6%, 100% and 95.9% at 18 F-FDG-PET/CT, and 91.4%, 85.7%, 94.1%, 80%, 89.8% at CI. Diagnostic performances of PET/CT and CI were not significantly different on a patient-based, side-by-side and level-by-level analysis. 18 F-FDG-PET/CT recognized distant metastases in 7 patients allowing to an upstaging. At a median follow-up of 27 months, relapse/progression of disease occurred in 31 patients and death occurred in 32. Metabolic tumor volume (MTV T), MTV total and total lesion glycolysis (TLG) showed to be independent prognostic factors for PFS.

CONCLUSIONS

Both CI and PET/CT had good diagnostic performances for the staging of laryngeal cancer; baseline metabolic features (MTV and TLG) showed an important prognostic value in assessing the rate of PFS.

A predictive model for treatment response in patients with locally advanced esophageal squamous cell carcinoma after concurrent chemoradiotherapy: based on SUVmean and NLR

Background

We conducted this study to combine the mean standardized uptake value (SUVmean) and neutrophil to lymphocyte ratio (NLR) to establish a strong predictive model for patients with esophageal squamous cell carcinoma (ESCC) after concurrent chemoradiotherapy (CCRT).

Methods

We retrospectively analyzed 163 newly diagnosed ESCC patients treated with CCRT. Eighty patients (training set) were randomly selected to generate cut-off SUVmean and NLR values by receiver operating characteristic (ROC) curve analysis and to establish a predictive model by using the independent predictors of treatment outcomes. Then, we evaluated the performance of the prediction model regarding treatment outcomes in the testing set (n = 83) and in all sets.

Results

A high SUVmean (> 5.81) and high NLR (> 2.42) at diagnosis were associated with unfavorable treatment outcomes in patients with ESCC. The prediction model had a better performance than the simple parameters (p < 0.05). With a cut-off value of 0.77, the prediction model significantly improved the specificity and positive predictive value for treatment response (88.9 and 92.1% in the training set, 95.8 and 97.1% in the testing set, and 92.2 and 91.8% in all sets, respectively).

Conclusions

The pretreatment SUVmean and NLR were independent predictors of treatment response in ESCC patients treated with CCRT. The predictive model was constructed based on these two parameters and provides a highly accurate tool for predicting patient outcomes.

Effects of Fever on 18F-FDG Distribution In Vivo: a Preliminary Study

PURPOSE

Elevated body temperature might change glucose metabolism in human organs. The purpose of this study is to explore ¹⁸F-FDG distribution in febrile patients on the day of ¹⁸F-FDG PET/CT scanning and compare it with patients with a normal temperature.

PROCEDURES

¹⁸F-FDG PET/CT was performed on 69 febrile patients and 82 patients with a normal temperature. Patient sociodemographic data, blood glucose levels before PET/CT, body temperature on the day of the exam, and laboratory test results were collected. Maximal standard uptake values (SUV_max) in the brain, mediastinal blood pool, liver, spleen, and the bone marrow were compared.

RESULTS

Compared with the controls, SUV_max of the febrile patients was significantly lower in the brain, mediastinal blood pool, and the liver (p < 0.01), and higher in the spleen and bone marrow (p < 0.01). In the febrile group, SUV_max was not significantly different between the FDG burden and non-FDG burden patients (p > 0.05). Body temperature was found negatively correlated with SUV_max in the brain (r = - 0.646), mediastinal blood pool (r = - 0.530), and the liver (r = - 0.384), and positively correlated with the SUV_max in the spleen (r = 0.592) and bone marrow (r = 0.651). Multivariate linear regression established body temperature on the day of PET/CT as an independent affecting factor (p < 0.01) for the SUV_max in the brain, mediastinal blood pool, liver, spleen, and bone marrow. The SUV in the brain, liver, and mediastinal blood pool remained different (p < 0.05) after corrected with the SUV_max in the blood pool or liver.

CONCLUSIONS

Fever influences ¹⁸F-FDG distribution in multiple human tissues and organs. Altered ¹⁸F-FDG distribution in vivo might affect results of disease lesion detection and tumor therapy response assessment. Correction with blood pool or liver SUV fails to cancel the effects of fever. The day of fever should be avoided for PET/CT scan, especially in assessing tumor therapy response.

Design study of a dedicated head and neck cancer PET system

The tumor-involved regions of head and neck cancer (HNC) have complex anatomical structures and vital physiological roles. As a consequence, there is a need for high sensitivity and high spatial resolution dedicated HNC PET scanner. The purpose of this study is to evaluate and optimize system design that includes detecting materials and geometries. For the detecting material, two scanners with the same two-panel geometry based on CZT and LYSO were evaluated. For the system geometry, four CZT scanners with two-panel, lengthened two-panel, four-panel, and full-ring geometries were evaluated. A cylinder phantom with sphere lesions and an XCAT phantom in the head and neck region were simulated. The results showed that the sensitivity of the 40-mm thickness CZT system and the 20-mm thickness LYSO system were comparable. However, the multiple interaction photon events recovery accuracy of the CZT system was about 20% higher. The in-panel and orthogonal-panel spatial resolutions of CZT are 0.58 and 0.74 mm, while those of LYSO are 0.70 and 1.40 mm. For system geometry, the four-panel and full-ring scanners have a higher contrast recovery coefficient (CRC) and contrast-to-noise ratio (CNR) than the two-panel and lengthened two-panel scanners. However, a 5-mm lesion in the XCAT phantom was visualized within 6 min in the two-panel system.

Assessment of tumour hypoxia, proliferation and glucose metabolism in head and neck cancer before and during treatment

OBJECTIVE

The aim of the study was to assess the feasibility of multitracer positron emission tomography (PET) imaging before and during chemoradiation and to evaluate the predictive value of image-based factors for outcome in locally advanced head and neck cancers treated with chemoradiation.

METHODS

In the week prior to the treatment [¹⁸F]-2-flu-2-deoxy-D-glucose (FDG), [¹⁸F]-3'-flu-3'deoxythymidine (FLT) and [¹⁸F]-flumisonidazole (FMISO) imaging was performed. FLT scans were repeated at 14 and 28 Gy and FMISO at 36 Gy. Overall survival, disease-free survival and local control were correlated with subvolume parameters, and with tumour-to-muscle ratio for FMISO. For every tracer, total metabolic tumour volume was calculated.

RESULTS

33 patients were included. No correlation was found between pre-treatment maximum standardised uptake value for FDG, FLT, FMISO and outcomes. Tumour volume measured on initial CT scans and initial FLT volume correlated with disease-free survivall (p = 0.007 and 0.04 respectively). FDG and FLT metabolic tumour volumes correlated significantly with local control (p = 0.005 and 0.02 respectively). In multivariate Cox analysis only individual initial TMRmax correlated with overall survival.

CONCLUSION

PET/CT imaging is a promising tool. However, various aspects of image analysis need further clinical validation in larger multicentre study employing uniform imaging protocol and standardisation, especially for hypoxia tracer.

ADVANCES IN KNOWLEDGE

Monitoring of biological features of the tumour using multitracer PET modality seems to be a feasible option in daily clinical practice.Evaluation of hypoxic subvolumes is more patient dependent; thus, exploration of individual parameters of hypoxia is needed. tumour-to-muscle ratio seems to be the most promising so far.

Integrating Tumor and Nodal Imaging Characteristics at Baseline and Mid-Treatment Computed Tomography Scans to Predict Distant Metastasis in Oropharyngeal Cancer Treated With Concurrent Chemoradiotherapy

PURPOSE

Prognostic biomarkers of disease relapse are needed for risk-adaptive therapy of oropharyngeal cancer (OPC). This work aims to identify an imaging signature to predict distant metastasis in OPC.

METHODS AND MATERIALS

This single-institution retrospective study included 140 patients treated with definitive concurrent chemoradiotherapy, for whom both pre- and midtreatment contrast-enhanced computed tomography (CT) scans were available. Patients were divided into separate training and testing cohorts. Forty-five quantitative image features were extracted to characterize tumor and involved lymph nodes at both time points. By incorporating both imaging and clinicopathological features, a random survival forest (RSF) model was built to predict distant metastasis-free survival (DMFS). The model was optimized via repeated cross-validation in the training cohort and then independently validated in the testing cohort.

RESULTS

The most important features for predicting DMFS were the maximum distance among nodes, maximum distance between tumor and nodes at mid-treatment, and pretreatment tumor sphericity. In the testing cohort, the RSF model achieved good discriminability for DMFS (C-index = 0.73, P = .008), and further divided patients into 2 risk groups with different 2-year DMFS rates: 96.7% versus 67.6%. Similar trends were observed for patients with p16+ tumors and smoking ≤10 pack-years. The RSF model based on pretreatment CT features alone achieved lower performance (concordance index = 0.68, P = .03).

CONCLUSIONS

Integrating tumor and nodal imaging characteristics at baseline and mid-treatment CT allows prediction of distant metastasis in OPC. The proposed imaging signature requires prospective validation and, if successful, may help identify high-risk human papillomavirus-positive patients who should not be considered for deintensification therapy.

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 (F-FDG) positron emission tomography/computed tomography (PET/CT). This retrospective study assessed the prognostic significance and feasibility of conformal radiotherapy for NPC, based on F-FDG PET/CT. Eighty-two patients with NPC underwent F-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.

Radiomics features analysis of PET images in oropharyngeal and hypopharyngeal cancer

This study used radiomics image analysis to examine the differences of texture feature values extracted from oropharyngeal and hypopharyngeal cancer positron emission tomography (PET) images on various tumor segmentations, and finds the proper and stable feature groups. A total of 80 oropharyngeal and hypopharyngeal cancer cases were retrospectively recruited. Radiomics method was applied to the PET image for the 80 oropharyngeal and hypopharyngeal cancer cases to extract texture features from various defined metabolic volumes. Kruskal-Wallis one-way analysis of variance method was used to test whether feature value difference exists between groups, which were grouped by stage, response to treatment, and recurrence. If there was a significant difference, the corresponding feature cutoff value was applied to the Kaplan-Meier estimator to estimate the survival functions. For the various defined metabolic volumes, there were 16 features that had significant differences between early (T1, T2) and late tumor stages (T3, T4). Five images and 2 textural features were found to be able to predict the tumor response and recurrence, respectively, with the areas under the receiver operating characteristic curves reaching 0.7. The histogram entropy was found to be a good predictor of overall survival (OS) and primary relapse-free survival (PRFS) of oropharyngeal and hypopharyngeal cancer patients. Textural features from PET images provide predictive and prognostic information in tumor staging, tumor response, recurrence, and have the potential to be a prognosticator for OS and PRFS in oropharyngeal and hypopharyngeal cancer.

Clinical Utility of Pretreatment and 3-Month 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Standardized Uptake Value in Predicting and Assessing Recurrence in T3-T4 Laryngeal Carcinoma Treated With Definitive Radiation

OBJECTIVES

The aim of this study was to investigate the utility of pretreatment and 3-month ¹⁸F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) standardized uptake value (SUV) in predicting and assessing recurrence in T3-T4 laryngeal carcinoma treated with definitive radiation therapy (RT).

METHODS

Patients with newly diagnosed T3-T4 laryngeal squamous cell carcinoma treated with definitive RT from 2004 to 2014 were reviewed. Patients who underwent pretreatment or 3-month PET/CT 2 to 4 months after treatment were included. Those with prior systemic, surgical, or RT treatment were excluded. The primary objective was to assess whether pretreatment or posttreatment maximum SUV of the primary site (pSUV) of disease was associated with local recurrence-free survival. Overall survival was a secondary end point. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to assess the accuracy of 3-month PET/CT at the larynx primary.

RESULTS

Twenty-eight patients were eligible for analysis. Median follow-up time was 34.7 months (range, 5.3-138.7 months), and median age was 57 years. Most patients had supraglottic (71.4%), T3 (89.3%), N2 (50.0%) disease, received chemotherapy (96.4%), and had histories of tobacco use (96.4%). On univariate analysis, 3-month posttreatment pSUV was associated with local recurrence-free survival ( P < .01), while pretreatment pSUV was not ( P = .41). No other associations were found with local recurrence-free survival. Neither pretreatment nor 3-month pSUV was significantly associated with overall survival. The calculated sensitivity, specificity, positive predictive value, and negative predictive value of 3-month PET/CT at the primary site were 33%, 85%, 40%, and 81%, respectively.

CONCLUSIONS

High initial fluorodeoxyglucose uptake in T3-T4 laryngeal primaries did not show an association with the risk for postradiation local relapse or overall survival, while increased fluorodeoxyglucose uptake at 3 months was associated with increased local recurrence. At 3 months, the relatively low sensitivity and positive predictive value may limit the utility of PET/CT in the assessment of persistent advanced laryngeal cancer after definitive radiation.

Role of pretreatment fluorodeoxyglucose positron emission tomography quantitative parameters in prognostication of head-and-neck squamous cell carcinoma

In spite of the good organ preservation strategies available for locally advanced head-and-neck squamous cell carcinoma (HNSCC), failure rates have been reported to be as high as 35%–50%. There has been an increasing interest in predicting response to treatment, to aid early intervention and better outcomes. Fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) is a standard modality for posttreatment evaluation; however, it is still underutilized as a pretreatment investigative modality. Several articles have described quantitative parameters in pretreatment FDG-PET to prognosticate patients and determine the likelihood of response to treatment; however, they are still not used commonly. This article was a review of the literature available on pretreatment FDG-PET quantitative parameters and their value in predicting failure. A thorough review of literature from MEDLINE and EMBASE was performed on pretreatment quantitative parameters in HNSCC. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were reliable parameters to predict response to organ preservation therapy, disease-free survival, and overall survival. Maximum SUV (SUVmax) was an inconsistent parameter. MTV and TLG may help predict poor response to organ preservation to initiate early surgical salvage or modify therapeutic decisions to optimize clinical outcomes. Routine use may provide additional information over SUVmax alone.

[18F]Fluorodeoxyglucose uptake by positron emission tomography predicts outcomes for oropharyngeal and hypopharyngeal cancer treated with definitive radiotherapy

This study evaluated the prognostic significance of the maximum standardized uptake value of the primary site (pSUVmax) in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans of patients with oropharyngeal or hypopharyngeal cancer who were treated using definitive radiotherapy. The study included 86 patients who were primarily treated with radiotherapy for oropharyngeal or hypopharyngeal cancer. Sixty-nine patients underwent concurrent chemotherapy. The associations between pre-treatment pSUVmax and treatment outcomes were evaluated. The most appropriate pSUVmax cut-off value for predicting disease-free survival (DFS) and local control (LC) was selected using receiver operating characteristic (ROC) curves. The median follow-up time for surviving patients was 60 months, while the median survival time in the entire patient cohort was 55 months. A pSUVmax cut-off value of 9.0 showed the best discriminative performance. Five-year OS and DFS rates were 65.9% and 60.0%, respectively. In univariate analyses, pSUVmax (p = 0.009), T-stage (p = 0.001), N-stage (p = 0.039), and clinical stage (p = 0.017) were identified as significant prognostic predictors for DFS. The multivariate analysis did not identify any statistically significant factors, but the association between pSUVmax and DFS was borderline significant (p = 0.055). Interestingly, pSUVmax was predictive of local controllability in T1–T2 disease (p = 0.024), but there was no significant association for T3–T4 disease (p = 0.735). In this study, pSUVmax was predictive of DFS and LC in patients with oropharyngeal or hypopharyngeal cancer that was treated with definitive radiotherapy. pSUVmax was strongly associated with LC in T1–T2 disease.

What is the prognostic impact of FDG PET in locally advanced head and neck squamous cell carcinoma treated with concomitant chemo-radiotherapy? A systematic review and meta-analysis

PURPOSE

Evidence is conflicting on the prognostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in head and neck squamous cell carcinoma. The aim of our study was to determine the impact of semiquantitative and qualitative metabolic parameters on the outcome in patients managed with standard treatment for locally advanced disease.

METHODS

A systematic review of the literature was conducted. A meta-analysis was performed of studies providing estimates of relative risk (RR) for the association between semiquantitative metabolic parameters and efficacy outcome measures.

RESULTS

The analysis included 25 studies, for a total of 2,223 subjects. The most frequent primary tumour site was the oropharynx (1,150/2,223 patients, 51.7%). According to the available data, the majority of patients had stage III/IV disease (1,709/1,799, 94.9%; no information available in four studies) and were treated with standard concurrent chemoradiotherapy (1,562/2,009 patients, 77.7%; only one study without available information). A total of 11, 8 and 4 independent studies provided RR estimates for the association between baseline FDG PET metrics and overall survival (OS), progression-free survival (PFS) and locoregional control (LRC), respectively. High pretreatment metabolic tumour volume (MTV) was significantly associated with a worse OS (summary RR 1.86, 95% CI 1.08-3.21), PFS (summary RR 1.81, 95% CI 1.14-2.89) and LRC (summary RR 3.49, 95% CI 1.65-7.35). Given the large heterogeneity (I2 > 50%) affecting the summary measures, no cumulative threshold for an unfavourable prognosis could be defined. No statistically significant association was found between SUVmax and any of the outcome measures.

CONCLUSION

FDG PET has prognostic relevance in the context of locally advanced head and neck squamous cell carcinoma. Pretreatment MTV is the only metabolic variable with a significant impact on patient outcome. Because of the heterogeneity and the lack of standardized methodology, no definitive conclusions on optimal cut-off values can be drawn.

Integrating quantitative morphological and intratumoural textural characteristics in FDG-PET for the prediction of prognosis in pharynx squamous cell carcinoma patients

AIM

To assess potential prognostic factors in pharynx squamous cell carcinoma (SCC) patients by quantitative morphological and intratumoural characteristics obtained by 2-[¹⁸F]-fluoro-2-deoxy-d-glucose positron-emission tomography/computed tomography (FDG-PET/CT).

MATERIALS AND METHODS

The cases of 54 patients with pharynx SCC who underwent chemoradiation therapy were analysed retrospectively. Using their FDG-PET data, the quantitative morphological and intratumoural characteristics of 14 parameters were calculated. The progression-free survival (PFS) and overall survival (OS) information was obtained from patient medical records. Univariate and multivariate analyses were performed to assess the 14 quantitative parameters as well as the T-stage, N-stage, and tumour location data for their relation to PFS and OS. When an independent predictor was suggested in the multivariate analysis, the parameter was further assessed using the Kaplan-Meier method.

RESULTS

In the assessment of PFS, the univariate and multivariate analyses indicated the following as independent predictors: the texture parameter of homogeneity and the morphological parameter of sphericity. In the Kaplan-Meier analysis, the PFS rate was significantly improved in the patients who had both a higher value of homogeneity (p=0.01) and a higher value of sphericity (p=0.002). With the combined use of homogeneity and sphericity, the patients with different PFS rates could be divided more clearly.

CONCLUSION

The quantitative parameters of homogeneity and sphericity obtained by FDG-PET can be useful for the prediction of the PFS of pharynx SCC patients, especially when used in combination.

Semi-quantitative analysis of pre-treatment morphological and intratumoral characteristics using 18F-fluorodeoxyglucose positron-emission tomography as predictors of treatment outcome in nasal and paranasal squamous cell carcinoma

Background

To investigate the utility of quantitative morphological and intratumoral characteristics obtained by ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) for the prediction of treatment outcome in patients with nasal or paranasal cavity squamous cell carcinoma (SCC).

Methods

Twenty-four patients with nasal or paranasal cavity SCC who received curative non-surgical therapy (a combination of super-selective arterial cisplatin infusion and radiotherapy) were retrospectively analyzed. From pre-treatment FDG-PET data, a total of 13 parameters of quantitative morphological characteristics (tumor volume, surface area and sphericity), intratumoral characteristics (the maximum and mean standard uptake value, three intratumoral histogram and four textural parameters) and total lesion glycolysis (TLG) were respectively calculated. Information regarding the treatment outcome was determined from the histological diagnosis or clinical follow-up. Each of the 13 quantitative parameters as well as T- and N-stage was assessed for its relation to treatment outcome of local control or failure.

Results

In univariate analysis, significant differences in surface area and sphericity between the local control and failure groups were observed. The receiver operating characteristic (ROC) curve analysis showed that sphericity had the highest accuracy of 0.88. In the multivariate analysis, sphericity was revealed as an independent predictor of the local control or failure.

Conclusions

The quantitative parameters of sphericity are useful to predict the treatment outcome in patients with nasal or paranasal SCC.

Radiomics in Nuclear Medicine Applied to Radiation Therapy: Methods, Pitfalls, and Challenges

Radiomics is a recent area of research in precision medicine and is based on the extraction of a large variety of features from medical images. In the field of radiation oncology, comprehensive image analysis is crucial to personalization of treatments. A better characterization of local heterogeneity and the shape of the tumor, depicting individual cancer aggressiveness, could guide dose planning and suggest volumes in which a higher dose is needed for better tumor control. In addition, noninvasive imaging features that could predict treatment outcome from baseline scans could help the radiation oncologist to determine the best treatment strategies and to stratify patients as at low risk or high risk of recurrence. Nuclear medicine molecular imaging reflects information regarding biological processes in the tumor thanks to a wide range of radiotracers. Many studies involving ¹⁸F-fluorodeoxyglucose positron emission tomography suggest an added value of radiomics compared with the use of conventional PET metrics such as standardized uptake value for both tumor diagnosis and prediction of recurrence or treatment outcome. However, these promising results should not hide technical difficulties that still currently prevent the approach from being widely studied or clinically used. These difficulties mostly pertain to the variability of the imaging features as a function of the acquisition device and protocol, the robustness of the models with respect to that variability, and the interpretation of the radiomic models. Addressing the impact of the variability in acquisition and reconstruction protocols is needed, as is harmonizing the radiomic feature calculation methods, to ensure the reproducibility of studies in a multicenter context and their implementation in a clinical workflow. In this review, we explain the potential impact of positron emission tomography radiomics for radiation therapy and underline the various aspects that need to be carefully addressed to make the most of this promising approach.

The prognostic value of positron emission tomography/computed tomography in pulmonary metastasectomy

Background

Although positron emission tomography/computed tomography (PET/CT) findings are prognostic in lung cancer patients, the prognostic value of PET/CT findings in patients with pulmonary metastases has neither been comprehensively investigated nor clarified. The aims of this retrospective study were to evaluate the value of PET/CT and identify novel prognostic indicators for pulmonary metastasectomy.

Methods

Between May 2004 and February 2017, 178 patients underwent PET/CT and resection of pulmonary metastases. After exclusion of patients who underwent biopsy only or duplicate cases, 142 patients were analyzed. Prognostic indicators, including PET/CT findings and outcomes were investigated.

Results

The median follow-up time was 42 months. The primary tumor site was colorectal in 76, kidney in 14, head and neck in 13, breast in 12, stomach in 8, urinary tract in 7, and other organs in 12 patients. The median maximal standardized uptake value (SUV_max) was 4.6. The optimal cut-off value, determined by receiver operating characteristic (ROC) analysis, identified the following cut-off values: disease-free interval (DFI) (12 months; SUV_max =4.5). Univariable analysis revealed that DFI ≤12 months, incomplete resection, and SUV_max ≥4.5 were significant for poor outcome. Multivariable analysis revealed incomplete resection and SUV_max ≥4.5 were significant for poor outcome. The 5-year survival rates of patients with SUV_max ≥4.5 and SUV_max <4.5 were 51.6% and 74.0%, respectively.

Conclusions

Analysis of patients undergoing pulmonary metastasectomy demonstrated that incomplete resection and an SUV_max ≥4.5 are significant prognostic indicators. PET/CT findings should be included in estimations of these patients' prognosis.

Prognostic Value of Volume-Based Positron Emission Tomography/Computed Tomography in Nasopharyngeal Carcinoma Patients after Comprehensive Therapy

Objective

We assessed the prognostic value of standardized uptake value (SUV) and volume-based methods including whole-body metabolic tumor volume (WBMTV) and whole-body total lesion glycolysis (WBTLG) using ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) of patients with nasopharyngeal carcinoma (NPC) after therapy.

Methods

A total of 221 posttherapy NPC cases were enrolled, all of whom had undergone PET/CT scanning and follow-up in this retrospective study. The diagnostic results of PET/CT were analyzed and compared with histopathological diagnosis or clinical follow-up. Receiver operator characteristic curves, the Kaplan-Meier method, and the log-rank test were used to assess the optimal cutoff values for WBMTV and WBTLG to identify independent predictors of survival.

Results

The detection rates of the threshold SUV were 2.5, 20%, and 40%, and SUV background methods were 65.6% (378/576), 80.2% (462/576), 71.5% (412/576), and 90.4% (521/576), respectively (P < 0.005). Patients with a WBMTV < 8.10 and/or a WBTLG < 35.58 had significantly better 5-year overall survival than those above the cutoffs (90.7% versus 51.2%, P < 0.001; 91.7% versus 50.4%, P < 0.001), respectively. Multivariate Cox regression modeling showed both WBTLG (RR, 1.002; P = 0.004) and age (RR, 1.046; P = 0.006) could be used to predict overall survival. WBTLG (RR, 1.003; P < 0.001) may have predictive relevance in estimating disease-free survival.

Conclusions

SUV volume-based threshold background methodology had a significantly higher detection rate for metastatic lesions. WBTLG could be used as an independent prognostic indicator for posttherapy NPC.

Prognostic value of simultaneous 18F-FDG PET/MRI using a combination of metabolo-volumetric parameters and apparent diffusion coefficient in treated head and neck cancer

Background

The aim of this study was to determine the usefulness of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) parameters provided by simultaneous ¹⁸F-fluorodeoxyglucose (FDG) PET/MRI for the prediction of treatment failure in surgically resected head and neck cancer. We hypothesized that PET parameters corrected by tumor cellularity (combined PET/MRI parameters) could predict the prognosis. On regional PET, maximum standardized uptake value (SUVmax) was measured as metabolic parameters. In addition, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were checked as metabolo-volumetric parameters. Mean apparent diffusion coefficient (ADCmean) of tumor was evaluated as the MRI parameter on the ADC map. Ratios between metabolic/metabolo-volumetric parameters and ADC were calculated as combined PET/MRI parameters. PET, MRI, and combined PET/MRI parameters were compared with clinicopathologic parameters in terms of treatment failure.

Results

Seventy-two patients (mean age = 55.9 ± 14.6 year, M: F = 45: 27) who underwent simultaneous ¹⁸F-FDG PET/MRI before head and neck cancer surgery were retrospectively enrolled. Twenty-two patients (30.6%) showed tumor treatment failure after head and neck cancer surgery (mean treatment failure = 13.0 ± 7.0 months). In the univariate analysis, MTV (P = 0.044) and ratios between metabolo-volumetric parameters and ADC (MTV/ADCmean, P = 0.022; TLG/ADCmean, P = 0.044) demonstrated significance among ¹⁸F-FDG PET/MRI parameters. Lymphatic invasion (P = 0.044) and perineural invasion (P = 0.046) revealed significance among clinicopathologic parameters. In the multivariate analysis, MTV (P = 0.026), MTV/ADCmean (P = 0.011), and TLG/ADCmean (P = 0.002) with lymphatic invasion (P = 0.026, 0.026, and 0.044, respectively) showed significance.

Conclusions

Combined PET/MRI parameters (PET metabolo-volumetric parameters corrected by tumor cellularity) could be effective predictors of tumor treatment failure after head and neck cancer surgery in addition to MTV and clinicopathologic parameter.

Electronic supplementary material

The online version of this article (10.1186/s13550-018-0357-9) contains supplementary material, which is available to authorized users.

Considering the Relationship between Quantitative Parameters and Prognostic Factors in Breast Cancer: Can Mean Standardized Uptake Value be an Alternative to Maximum Standardized Uptake Value?

It was aimed to investigate the correlation between maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), and retention index (RI), which represents the quantitative evaluation of the uptake of ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) used in positron emission tomography (PET) and clinicopathologic as well as biologic prognostic factors. Forty-one women with breast cancer who were histopathologically diagnosed were included in this study. Neoadjuvant chemotherapy was applied to all patients before PET/computed tomography (CT). After FDG injection, PET/CT screening was applied within the 1^st h (PET-1) and in the 2^nd h (PET-2). SUVmax, SUVmean, SUVmax RI, and SUVmean RI of every image were calculated qualitatively and semiquantitatively. The correlation between quantitative and semiquantitative PET parameters and biologic as well as clinicopathologic prognosis factors was evaluated. Statistically, significant positive correlation was found between lymph nodes (LNs), which were evaluated by clinical picture, clinical stage as well as histopathologically and quantitative PET parameters (SUVmax1, SUVmax2,, RImax, SUVmean1, SUVmean2, RImean) (P < 0.05). While statistically significant correlation with RImax was detected only by LN (histopathological), correlations with RImean were detected by clinical picture, clinical stage, metabolic stage, and LN (histopathological). Statistically, significant correlation was found between RImax and estrogen receptor in patients who were histopathologically diagnosed with invasive ductal carcinoma (n = 34) (P < 0.05). We detected correlations between biologic and clinicopathologic prognostic factors and SUVmax as well as SUVmean values in breast carcinoma. SUVmean values may provide important knowledge when the correlation between prognostic factors and PET parameters is investigated even if they are not used routinely.

Beyond Correlations, Sensitivities, and Specificities: Case Examples of the Evaluation of Advanced Imaging in Oncology Clinical Trials and Cancer Treatment

Although advanced imaging is an important component of oncology clinical trials, there has not been a lot of success in advancing its use from a research perspective. One likely reason is the lack of consensus on the methodology used to study advanced imaging in trials, which results in a disconcerted research effort and produces data that are difficult to collate for use in validating the imaging components being studied. Imaging is used in cancer clinical trials for various indications, and the study design needed to evaluate the imaging in a particular indication will vary. Through case examples, this paper will discuss how advanced imaging is currently being investigated in oncology clinical trials, categorized by the potential clinical indication for the imaging tool and offer suggestions on how development should proceed to further evaluate imaging in the given indication. Available National Cancer Institute resources that can assist in this process will also be discussed.

Predictive modeling of outcomes following definitive chemoradiotherapy for oropharyngeal cancer based on FDG-PET image characteristics

In this study, we investigate the use of imaging feature-based outcomes research ('radiomics') combined with machine learning techniques to develop robust predictive models for the risk of all-cause mortality (ACM), local failure (LF), and distant metastasis (DM) following definitive chemoradiation therapy (CRT). One hundred seventy four patients with stage III-IV oropharyngeal cancer (OC) treated at our institution with CRT with retrievable pre- and post-treatment 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans were identified. From pre-treatment PET scans, 24 representative imaging features of FDG-avid disease regions were extracted. Using machine learning-based feature selection methods, multiparameter logistic regression models were built incorporating clinical factors and imaging features. All model building methods were tested by cross validation to avoid overfitting, and final outcome models were validated on an independent dataset from a collaborating institution. Multiparameter models were statistically significant on 5 fold cross validation with the area under the receiver operating characteristic curve (AUC)  =  0.65 (p  =  0.004), 0.73 (p  =  0.026), and 0.66 (p  =  0.015) for ACM, LF, and DM, respectively. The model for LF retained significance on the independent validation cohort with AUC  =  0.68 (p  =  0.029) whereas the models for ACM and DM did not reach statistical significance, but resulted in comparable predictive power to the 5 fold cross validation with AUC  =  0.60 (p  =  0.092) and 0.65 (p  =  0.062), respectively. In the largest study of its kind to date, predictive features including increasing metabolic tumor volume, increasing image heterogeneity, and increasing tumor surface irregularity significantly correlated to mortality, LF, and DM on 5 fold cross validation in a relatively uniform single-institution cohort. The LF model also retained significance in an independent population.

The maximum standardized uptake value increment calculated by dual-time-point 18F-fluorodeoxyglucose positron emission tomography predicts survival in patients with oral tongue squamous cell carcinoma

The aim of this study was to investigate the prognostic value of dual-time-point (DTP) ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) imaging in primary oral tongue squamous cell carcinoma (OTSCC). The study included 52 patients who underwent preoperative ¹⁸F-FDG PET scans at two time points, namely 1 h and 2 h after injection. The following PET parameters were calculated: maximum standardized uptake value (SUVmax) for both time points (SUV early, SUV delayed); retention index (RI); and SUVmax increment (ΔSUVmax). Receiver operating characteristic (ROC) curve analysis was performed to define the optimal cutoff point for these parameters. Overall survival was calculated using the Kaplan–Meier method. Prognostic factors for patients with OTSCC were evaluated using the univariate log-rank test and a multivariate Cox proportional hazards model. ROC analysis revealed that the area under the curve was higher and more accurate for ΔSUVmax than for the other parameters. Additionally, patients with a ΔSUVmax ≥0.9 had significantly worse survival outcomes (28.9% vs 92.6%; p < 0.01). Univariate analysis showed that prognosis was significantly correlated with clinical T stage, local recurrence, perineural invasion, vascular invasion, and PET parameters (p < 0.05 for all). Multivariate analysis showed that local recurrence (hazard ratio = 3.60; p = 0.02) and ΔSUVmax (hazard ratio = 8.43; p < 0.01) were independent prognostic factors. ΔSUVmax determined using DTP ¹⁸F-FDG PET may be an additional prognostic factor in OTSCC patients.

Prognostic value of maximum standardized uptake value measured by pretreatment 18F-FDG PET/CT in locally advanced head and neck squamous cell carcinoma

PURPOSE/OBJECTIVES

To evaluate the prognostic impact of maximum standardized uptake value (SUV_max) in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) undergoing pretreatment [F-18] fluoro-D-glucose-positron emission tomography/computed tomography (FDG PET/CT) imaging.

MATERIALS/METHODS

Fifty-eight patients undergoing FDG PET/CT before radical treatment with definitive radiotherapy (±concomitant chemotherapy) or surgery + postoperative (chemo)radiation were analyzed. The effects of clinicopathological factors (age, gender, tumor location, stage, Karnofsky Performance Status (KPS), and treatment strategy) including primary tumor SUV_max and nodal SUV_max on overall survival (OS), disease-free survival (DFS), locoregional control (LRC), and distant metastasis-free survival (DMFS) were evaluated. Kaplan-Meier survival curves were generated and compared with the log-rank test.

RESULTS

Median follow-up for the whole population was 31 months (range 2.3-53.5). Two-year OS, LRC, DFS and DMFS, for the entire cohort were 62.1, 78.3, 55.2 and 67.2%, respectively. Median pretreatment SUV_max for the primary tumor and lymph nodes was 11.85 and 5.4, respectively. According to univariate analysis, patients with KPS < 80% (p < 0.001), AJCC stage IVa or IVb vs III (p = 0.037) and patients undergoing radiotherapy vs surgery (p = 0.042) were significantly associated with worse OS. Patients with KPS < 80% (p = 0.003) or age ≥65 years (p = 0.007) had worse LRC. The KPS < 80% was the only factor associated with decreased DFS (p = 0.001). SUV_max of the primary tumor or the lymph nodes were not associated with OS, DFS or LRC. The KPS < 80% (p = 0.002), tumor location (p = 0.047) and AJCC stage (p = 0.025) were associated with worse cancer-specific survival (CSS). According to Cox regression analysis, on multivariate analysis KPS < 80% was the only independent parameter determining worse OS, DFS, CSS. Regarding LRC only patients with IK < 80% (p = 0.01) and ≥65 years (p = 0.01) remained statistically significant. Nodal SUV_max was the only factor associated with decreased DMFS. Patients with a nodal SUV_max > 5.4 presented an increased risk for distant metastases (HR, 3.3; 95% CI 1.17-9.25; p = 0.023).

CONCLUSIONS

The pretreatment nodal SUV_max in patients with locally advanced HNSCC is prognostic for DMFS. However, according to our results primary tumor SUV_max and nodal SUV_max were not significantly related to OS, DFS or LRC. Patients presenting KPS < 80% had worse OS, DFS, CSS and LRC.

Correlation of Positron Emission Tomography/Computed Tomography Scan with Smoking, Tumor Size, Stage and Differentiation in Head and Neck Cancer Patients

The goal of this study was to identify associations between positron emission tomography/computed tomography (PET/CT) maximum standardized uptake value (SUVmax) in patients presenting with head and neck squamous cell carcinoma (SCC) with tumor site, size, histologic differentiation, smoking, and diabetes. Charts of patients with oropharyngeal and laryngeal SCC who underwent ¹⁸F-fluorodeoxyglucose PET/CT scans were reviewed between May 2007 and August 2013. Statistical analyses included modeling log-transformed SUVmax values by tumor site, size, histologic differentiation, smoking status, and diabetes using unadjusted linear regressions. Differences were considered statistically significant for P< 0.05. A total of 111 patients (54 with oropharynx and 57 with larynx cancers) were included, 83 men and 28 women with an average age of 57.5 years old. There was a significantly higher pack-year smoking history (P = 0.005) in the larynx cancer group. While tumor T-stage was found to be significantly different (P < 0.0001), there was no difference in tumor size between the two groups: 3.16 cm and 3.58 cm in the oropharynx and larynx, respectively (P = 0.55). In the oropharynx cohort, SUVmax was associated with both tumor size (P = 0.0001) and stage (P < 0.0002). Interestingly, SUVmax differed by tumor differentiation in the larynx (P = 0.04) but not the oropharynx (P = 0.71). Finally, there was no significant difference in SUVmax relative to diabetes and smoking status. PET/CT SUVmax correlated with both tumor size and stage in oropharyngeal cancer patients, and it correlated only with tumor differentiation but not the size or stage in the larynx. There were no significant differences in SUVmax by diabetes or smoking status.

Overview of the predictive value of quantitative 18 FDG PET in head and neck cancer treated with chemoradiotherapy

18 F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) allows to quantify the metabolic activity of a tumor (glycolysis) and has become a reference tool in oncology for the staging, restaging, radiotherapy planning and monitoring response in many cancers. Quantitative analyses have been introduced in order to overcome some of the limits of the visual methods, allowing an easier and more objective comparison of the inter- and intra-patients variations. The aims of this review were to report available evidences on the clinical value of quantitative PET/CT parameters in HNC. Forty-five studies, for a total of 2928 patients, were analyzed. Most of the data available dealt with the intensity of the metabolism, calculated from the Standard Uptake Value (SUV). Metabolic Tumor Volume (MTV) was well correlated with overall survival and disease free survival, with a higher predictive value than the maximum SUV. Spatial distribution of metabolism and textural analyses seems promising.

Role of fluorine-18 fluorodeoxyglucose PET/CT in head and neck oncology: the point of view of the radiation oncologist

Squamous cell carcinoma is the most common malignant tumour of the head and neck. The initial TNM staging, the evaluation of the tumour response during treatment, and the long-term surveillance are crucial moments in the approach to head and neck squamous cell carcinoma (HNSCC). Thus, at each of these moments, the choice of the best diagnostic tool providing the more precise and larger information is crucial. Positron emission tomography with fluorine-18 fludeoxyglucose integrated with CT (¹⁸F-FDG-PET/CT) rapidly gained clinical acceptance, and it has become an important imaging tool in routine clinical oncology. However, controversial data are currently available, for example, on the role of ¹⁸F-FDG-PET/CT imaging during radiotherapy planning, the prognostic value or its real clinical impact on treatment decisions. In this article, the role of ¹⁸F-FDG-PET/CT imaging in HNSCC during pre-treatment staging, radiotherapy planning, treatment response assessment, prognosis and follow-up is reviewed focusing on current evidence and controversial issues. A proposal on how to integrate ¹⁸F-FDG-PET/CT in daily clinical practice is also described.

The role of PET/CT in the management of patients affected by head and neck tumors: a review of the literature

The management of head and neck tumor (HNSCC) has been changing over the years, especially due to the aid of imaging techniques that help physicians to attain a correct diagnosis. These techniques represent a valuable tool to help tailor treatment and during follow-up of patients affected by malignancies. The aim of this review is to summarize the results of the most recent and relevant studies about the use of PET imaging in HNSCCs. This review is divided into six chapters: (1) The role of PET/CT in the pre-treatment phase; (2) PET/CT and radiotherapy planning; (3) PET/CT in the post-treatment setting; (4) PET/CT and SUVmax for prediction of prognosis; (5) miscellanea on the utility of PET in specific HNSCCs; (6) non-FDG PET tracers used in HNSCC. Promising results have been obtained so far. Despite the encouraging outcomes, more investigations are needed to warrant the value of this technique, especially in the pre-treatment setting.