18F-FDG PET/CT quantification in head and neck squamous cell cancer: principles, technical issues and clinical applications

Correlation of preoperative 18F-FDG-PET/CT tumor staging and maximum standardized uptake values with preoperative CT, postoperative tumor classification, and histopathological parameters of oral squamous cell carcinoma

INTRODUCTION

This study aimed to correlate preoperative 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) tumor staging, and maximum standardized uptake values (SUVmax) with preoperative CT data, postoperative tumor classification, and histopathological parameters of oral squamous cell carcinoma (OSCC).

MATERIAL AND METHODS

Thirty-seven OSCC patients staged via full-body 18F-FDG-PET/CT, including contrast agent CT of the head and neck in 2020 and 2021, were enclosed. Patients received tumor resection and stage-dependent neck dissection. Preoperative clinical (c) 18F-FDG-PET/CT UICC tumor stages and TNM classifications were correlated to corresponding CT and to postoperative histopathological (p) UICC tumor stages and TNM classifications. SUVmax of the primary tumor was associated with pUICC and pTNM, including extranodal extension (ENE), perineural invasion (Pn), lymphatic spread (L), vascular invasion (V), tumor grading (G), and -thickness.

RESULTS

Comparing 18F-FDG-PET/CT and CT, cUICC, cT, and cN differed in 32.3%, 16.7%, and 37.8% of the cases, respectively. For 18F-FDG-PET/CT, a moderate correlation was found between c- and pUICC (0.494; p = 0.0018) with a misestimation of c- compared to pUICC in 43.2% of the cases. Comparing c- and pTNM, misestimations concerning c- and pT were seen in 51.4% and concerning c- and pN in 37.8% of the cases. An increased SUVmax significantly correlated with increased pT- and pUICC (adjusted Odds ratio 1.103; p = 0.042 and 1.126; p = 0.021, respectively). The predictive quality of an SUVmax cutoff value for detecting cervical lymph node metastases and G was poor, as indicated by the low AUC values from the ROC analysis. No correlations were found between SUVmax and ENE, Pn-, L-, and V-status. A strong correlation was found between SUVmax and tumor thickness with an adjusted coefficient of 1.034 (p = 0.01).

CONCLUSION

The predictive value of 18F-FDG-PET/CT and SUVmax on histopathological tumor classification and parameters appears limited.

CLINICAL RELEVANCE

18F-FDG-PET/CT can not unreservedly be recommended for primary OSCC staging. There is an urgent need to specify its indications in detail further.

FDG PET-CT missed tibial metastasis in head and neck cancer, case report and systematic review

INTRODUCTION

Head and neck squamous cell carcinoma (HNSCC) is the seventh most common type of cancer in the world. Metastases occur in up to 40 % of cases and bones are the second most frequent site. Metastases in extremities are uncommon with very few publications covering distal lower-limb bone metastasis.

CASE PRESENTATION

Here we report the case of a patient with HNSCC managed by induction chemotherapy, surgery and adjuvant chemo-radiotherapy. During the adjuvant treatment, the patient presented pain in the right tibia, with additional workup revealing a distal lower-limb bone metastasis which had remained undetected during the recommended standard workup for HNSCC.

DISCUSSION

Current guidelines request that FDG PET-CT is performed down to the popliteal fossae. The undetected metastasis led to overtreatment of the patient. Systematic review of the literature showed only six cases of head and neck cancer's distal lower-limb metastasis which are eligible for discussion.

CONCLUSION

Although rare, physicians should keep in mind that as recommended FDG PET-CT does not extend below the popliteal fossae, metastases could be missed and therefore lead to inappropriate treatment.

Clinical significance of post-chemoradiotherapy 2-[18F]FDG PET/CT response in locally advanced nasopharyngeal carcinoma: A real-world study

PURPOSE

To investigate the prognostic value of post-chemoradiotherapy 2-[18F]FDG PET/CT in locally advanced nasopharyngeal carcinoma (LANPC) and develop an accurate prognostic model based on the 2-[18F]FDG PET/CT results.

METHODS

900 LANPC patients who underwent pretreatment and post-chemoradiotherapy 2-[18F]FDG PET/CT from May 2014 to August 2022 were included in the study. We divided the patients into two distinct cohorts for the purpose of our study: a training cohort comprising 506 individuals, included from May 2008 to April 2020, and a validation cohort consisting of 394 individuals, included from May 2020 to August 2022. PET/CT were assessed using the improved Deauville score (iDS) system. Cox regression analysis was performed to select candidate variables. A prognostic model was developed by the training cohort, and validated using the independent validation cohort.

RESULTS

Age (HR, 2.262(1.488-3.439); p＜0.001), ECOG (HR, 2.450 (1.395-4.301); p = 0.002), post-treatment EBV DNA level (HR, 2.208 (1.289-3.784); p = 0.004) and iDS {[iDS1-2 vs iDS3-4: HR, 3.781 (1.996-7.163); p＜0.001]; [iDS1-2 vs iDS5: HR, 11.707 (5.884-23.295); p＜0.001]}were independent predictors of OS. A 4-factor prognostic model developed and subsequently validated. This innovative model demonstrated excellent discrimination (C-index: 0.862). The calibration curves revealed a close match between the predicted probabilities and the actual outcomes, and decision curve analysis (DCA) confirmed the nomogram's utility for guiding clinical decision-making.

CONCLUSION

Our study validated the predictive value of the iDS system in determining outcome for LANPC. The 4-factor prognostic model, which integrates baseline patient characteristics with iDS, demonstrated good discrimination, agreement, and clinical application potential.

Application of Dynamic [18F]FDG PET/CT Multiparametric Imaging Leads to an Improved Differentiation of Benign and Malignant Lung Lesions

PURPOSE

To evaluate the potential of whole-body dynamic (WBD) 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) multiparametric imaging in the differential diagnosis between benign and malignant lung lesions.

PROCEDURES

We retrospectively analyzed WBD PET/CT scans from patients with lung lesions performed between April 2020 and March 2023. Multiparametric images including standardized uptake value (SUV), metabolic rate (MRFDG) and distribution volume (DVFDG) were visually interpreted and compared. We adopted SUVmax, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) for semi-quantitative analysis, MRmax and DVmax values for quantitative analysis. We also collected the patients' clinical characteristics. The variables above with P-value < 0.05 in the univariate analysis were entered into a multivariate logistic regression. The statistically significant metrics were plotted on receiver-operating characteristic (ROC) curves.

RESULTS

A total of 60 patients were included for data evaluation. We found that most malignant lesions showed high uptake on MRFDG and SUV images, and low or absent uptake on DVFDG images, while benign lesions showed low uptake on MRFDG images and high uptake on DVFDG images. Most malignant lesions showed a characteristic pattern of gradually increasing FDG uptake, whereas benign lesions presented an initial rise with rapid fall, then kept stable at a low level. The AUC values of MRmax and SUVmax are 0.874 (95% CI: 0.763-0.946) and 0.792 (95% CI: 0.667-0.886), respectively. DeLong's test showed the difference between the areas is statistically significant (P < 0.001).

CONCLUSIONS

Our study demonstrated that dynamic [18F]FDG PET/CT imaging based on the Patlak analysis was a more accurate method of distinguishing malignancies from benign lesions than conventional static PET/CT scans.

Role of 18F-FDG PET/CT in Head and Neck Squamous Cell Carcinoma: Current Evidence and Innovative Applications

This article provides an overview of the use of 18F-FDG PET/CT in various clinical scenarios of head-neck squamous cell carcinoma, ranging from initial staging to treatment-response assessment, and post-therapy follow-up, with a focus on the current evidence, debated issues, and innovative applications. Methodological aspects and the most frequent pitfalls in head-neck imaging interpretation are described. In the initial work-up, 18F-FDG PET/CT is recommended in patients with metastatic cervical lymphadenectomy and occult primary tumor; moreover, it is a well-established imaging tool for detecting cervical nodal involvement, distant metastases, and synchronous primary tumors. Various 18F-FDG pre-treatment parameters show prognostic value in terms of disease progression and overall survival. In this scenario, an emerging role is played by radiomics and machine learning. For radiation-treatment planning, 18F-FDG PET/CT provides an accurate delineation of target volumes and treatment adaptation. Due to its high negative predictive value, 18F-FDG PET/CT, performed at least 12 weeks after the completion of chemoradiotherapy, can prevent unnecessary neck dissections. In addition to radiomics and machine learning, emerging applications include PET/MRI, which combines the high soft-tissue contrast of MRI with the metabolic information of PET, and the use of PET radiopharmaceuticals other than 18F-FDG, which can answer specific clinical needs.

Combined average standard uptake value and rate constant can predict expression of EGFR in hypopharyngeal squamous cell carcinoma: A pilot study with integrated PET/MRI

PURPOSE

To investigate whether the quantitative multiparameters of 18F-FDG PET/MRI can predict expression of epidermal growth factor receptor (EGFR) of hypopharyngeal squamous cell carcinoma (HSCC).

METHODS

Twenty-one patients with HSCC confirmed by biopsy underwent neck integrated 18F-FDG PET/MRI and EGFR expression detection. Quantitative parameters derived from 18F-FDG PET, difusion-weighted imaging (DWI), and dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) were measured. The efficacies of quantitative multiparameters derived from 18F-FDG PET/MRI for predicting the expression of EGFR of HSCC were evaluated.

RESULTS

The patients were divided into positive expression group (PEG, n = 14) and negative expression group (NEG, n = 7). Mann-Whitney U nonparametric test showed that SUVmean and Kep had statistical difference between PEG and NPG, while other parameters had no statistical difference. Using 14.50 and 2.10 min-1 as the threshold values, areas under the curve (AUCs) for SUVmean and Kep were 0.786 with specificity of 92.9 % and sensitivity of 57.1 %. The combined use of SUVmean and Kep had better efficacy to evaluate the expression of EGFR with AUC of 0.980, sensitivity of 92.9 %, and specificity of 100.0 %.

CONCLUSION

Combined use of SUVmean and Kep showed good performance in predicting the expression of EGFR in HSCC. Integrated 18F-FDG PET/MRI enables simultaneous acquisition of SUVmean and Kep, so it represents as a powerful tool to noninvasively and repeatably evaluate the expression of EGFR during the management of HSCC.

Role of 18F-FDG PET/CT in evaluating lymph node status in patients with head and neck squamous cell carcinoma

Objective

The presence of cervical lymph node metastases (CLNM) at diagnosis is one of the most relevant negative prognostic factors in patients with head and neck squamous cell carcinoma (HNSCC). The aim of this study was to analyse 2-deoxy-2[18F]fluoro-D-glucose (FDG) PET/CT findings for the identification of primary tumours and CLNM in a sample of patients affected by HNSCC. Moreover, a maximum standardised uptake value (SUVmax) threshold for the detection of CLNM was estimated. Clinical variables (i.e. smoking and alcohol habits), and tumour features (i.e. EBV and HPV positivity) were also evaluated in relation to FDG PET/CT findings.

Methods

We retrospectively analysed patients who underwent FDG PET/CT for HNSCC staging between 2015-2020 at the University Hospital of Ferrara. All patients had cytological or histological confirmation of suspected cervical lymph nodes.

Results

In total, 65 patients were enrolled (53 males, 12 females, median age 65.7 years). CLNM of patients with smoking habit had significantly higher SUVmax values than those of patients with previous smoking habit and non-smokers (p = 0.04). p16 positive HNSCC demonstrated a trend for higher SUVmax values on CLNM, in comparison to p16 negative tumours (p = 0.089). ROC curve analysis identified 5.8 as the best cut-off value of SUVmax for the detection of CLNM (AUC = 0.62, sensitivity 71.4% and specificity 72.7%).

Conclusions

FDG PET/CT is a useful tool to evaluate CLNM in patients with HNSCC, particularly in those with smoking habit and p16 positive disease. A SUVmax cut-off of 5.8, combined with the use of conventional radiological investigations, may represent a useful tool in the identification of CLNM.

The Prognostic and Diagnostic Value of [18F]FDG PET/CT in Untreated Laryngeal Carcinoma

This study aims to determine the diagnostic accuracy of staging PET/CT and neck MRI in patients with laryngeal carcinoma and to assess the value of PET/CT in predicting progression-free survival (PFS) and overall survival (OS). Sixty-eight patients who had both modalities performed before treatment between 2014 and 2021 were included in this study. The sensitivity and specificity of PET/CT and MRI were evaluated. PET/CT had 93.8% sensitivity, 58.3% specificity, and 75% accuracy for nodal metastasis, whereas MRI had 68.8%, 61.1%, and 64.7% accuracy, respectively. At a median follow-up of 51 months, 23 patients had developed disease progression and 17 patients had died. Univariate-survival analysis revealed all utilized PET parameters as significant prognostic factors for OS and PFS (p-value < 0.03 each). In multivariate analysis, metabolic-tumor volume (MTV) and total lesion glycolysis (TLG) predicted better PFS (p-value < 0.05 each). In conclusion, PET/CT improves the accuracy of nodal staging in laryngeal carcinoma over neck MRI and adds to the prognostication of survival outcomes through the use of several PET metrics.

Prediction of outcomes in patients with local recurrent nasopharyngeal carcinoma: development and validation of a four-factor prognostic model integrating baseline characteristics and [18F]FDG PET/CT parameters

OBJECTIVES

To investigate the prognostic value of [¹⁸F]FDG PET/CT parameters in local recurrent nasopharyngeal carcinoma (lrNPC) and establish a prognostic tool for lrNPC patients based on these [¹⁸F]FDG PET/CT parameters.

METHODS

A total of 358 lrNPC patients seen from 2010 to 2019 at Sun Yat-sen University Cancer Center with complete baseline characteristics and [¹⁸F]FDG PET/CT data were retrospectively analyzed. Maximal standardized uptake value (SUVmax), SUVmean, SUVpeak, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and heterogeneity index (HI) for recurrent nasopharynx tumors were included. Cox regression analysis was performed to select candidate variables. Subsequently, a nomogram for predicting overall survival (OS) for lrNPC patients was developed and internally validated.

RESULTS

Multivariate Cox analysis results suggested that age ≥ 47 years (hazard ratio (HR), 1.62 (1.18-2.24); p = 0.003)，with smoking history (HR, 1.41 (1.01-1.98); p = 0.046), recurrent T stage {[rT3 vs rT1/2: HR, 1.81 (1.04-3.12); p = 0.037]; [rT4 vs rT1/2: HR, 2.46 (1.32-4.60); p = 0.005]}, and TLG {[37.1-184.3 vs ≤ 37.1: HR, 2.26 (1.49-3.42); p < 0.001]; [>184.3 vs ≤ 37.1: HR, 4.31 (2.50-7.43); p < 0.001]) were independent predictors of OS. A 4-factor nomogram was generated to stratify patients into 3 risk groups. This novel model showed good discrimination with a high C-index (0.752, 95%CI: 0.714-0.790). In addition, the calibration curves showed good agreement between the predicted probabilities and actual observations and decision curve analysis (DCA) suggested that the nomogram was useful for clinical decision-making.

CONCLUSIONS

Our study confirmed that [¹⁸F]FDG PET/CT parameters were valuable in predicting OS and PFS for lrNPC patients. The 4-factor prognostic model combing baseline patient characteristics with [¹⁸F]FDG PET/CT parameters for lrNPC patients had good discrimination, agreement, and clinical application potential.

KEY POINTS

• [¹⁸F]FDG PET/CT parameters were valuable in predicting OS and PFS for lrNPC patients. • The novel 4-factor nomogram for lrNPC patients had good discrimination, agreement, and potential for clinical application.

Functional-structural sub-region graph convolutional network (FSGCN): Application to the prognosis of head and neck cancer with PET/CT imaging

BACKGROUND AND OBJECTIVE

Accurate risk stratification is crucial for enabling personalized treatment for head and neck cancer (HNC). Current PET/CT image-based prognostic methods include radiomics analysis and convolutional neural network (CNN), while extracting radiomics or deep features in grid Euclidean space has inherent limitations for risk stratification. Here, we propose a functional-structural sub-region graph convolutional network (FSGCN) for accurate risk stratification of HNC.

METHODS

This study collected 642 patients from 8 different centers in The Cancer Imaging Archive (TCIA), 507 patients from 5 centers were used for training, and 135 patients from 3 centers were used for testing. The tumor was first clustered into multiple sub-regions by using PET and CT voxel information, and radiomics features were extracted from each sub-region to characterize its functional and structural information, a graph was then constructed to format the relationship/difference among different sub-regions in non-Euclidean space for each patient, followed by a residual gated graph convolutional network, the prognostic score was finally generated to predict the progression-free survival (PFS).

RESULTS

In the testing cohort, compared with radiomics or FSGCN or clinical model alone, the model PETCT^Fea_CT^ROI + Cli that integrates FSGCN prognostic score and clinical parameter achieved the highest C-index and AUC of 0.767 (95% CI: 0.759-0.774) and 0.781 (95% CI: 0.774-0.788), respectively for PFS prediction. Besides, it also showed good prognostic performance on the secondary endpoints OS, RFS, and MFS in the testing cohort, with C-index of 0.786 (95% CI: 0.778-0.795), 0.775 (95% CI: 0.767-0.782) and 0.781 (95% CI: 0.772-0.789), respectively.

CONCLUSIONS

The proposed FSGCN can better capture the metabolic or anatomic difference/interaction among sub-regions of the whole tumor imaged with PET/CT. Extensive multi-center experiments demonstrated its capability and generalization of prognosis prediction in HNC over conventional radiomics analysis.

Predicting local persistence/recurrence after radiation therapy for head and neck cancer from PET/CT using a multi-objective, multi-classifier radiomics model

Objectives

Accurate identifying head and neck squamous cell cancer (HNSCC) patients at high risk of local persistence/recurrence (P/R) is of importance for personalized patient management. Here we developed a multi-objective, multi-classifier radiomics model for early HNSCC local P/R prediction based on post-treatment PET/CT scans and clinical data.

Materials and methods

We retrospectively identified 328 individuals (69 patients have local P/R) with HNSCC treated with definitive radiation therapy at our institution. The median follow-up from treatment completion to the first surveillance PET/CT imaging was 114 days (range: 82-159 days). Post-treatment PET/CT scans were reviewed and contoured for all patients. For each imaging modality, we extracted 257 radiomic features to build a multi-objective radiomics model with sensitivity, specificity, and feature sparsity as objectives for model training. Multiple representative classifiers were combined to construct the predictive model. The output probabilities of models built with features from various modalities were fused together to make the final prediction.

Results

We built and evaluated three single-modality models and two multi-modality models. The combination of PET, CT, and clinical data in the multi-objective, multi-classifier radiomics model trended towards the best prediction performance, with a sensitivity of 93%, specificity of 83%, accuracy of 85%, and AUC of 0.94.

Conclusion

Our study demonstrates the feasibility of employing a multi-objective, multi-classifier radiomics model with PET/CT radiomic features and clinical data to predict outcomes for patients with HNSCC after radiation therapy. The proposed prediction model shows the potential to detect cancer local P/R early after radiation therapy.

Skeletal muscle mass at C3 may not be a strong predictor for skeletal muscle mass at L3 in sarcopenic patients with head and neck cancer

PURPOSE

To evaluate the feasibility of using skeletal muscle mass (SMM) at C3 (C3 SMM) as a diagnostic marker for sarcopenia in head and neck cancer (HNC) patients.

METHODS

We evaluated 165 HNC patients and 42 healthy adults who underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography scans. The paravertebral muscle area at C3 and skeletal muscle area at L3 were measured by CT. Pearson's correlation was used to assess the relationship between L3 and C3 SMMs. The prediction model for L3 SMM was developed by multiple linear regression. Then the correlation and the agreement between actual and predicted L3 SMMs were assessed. To evaluate the diagnostic value of C3 SMM for sarcopenia, the receiver operating characteristics (ROC) curves were analyzed.

RESULTS

Of the 165 HNC patients, 61 (37.0%) were sarcopenic and 104 (63.0%) were non-sarcopenic. A very strong correlation was found between L3 SMM and C3 SMM in both healthy adults (r = 0.864) and non-sarcopenic patients (r = 0.876), while a fair association was found in sarcopenic patients (r = 0.381). Prediction model showed a very strong correlation between actual SMM and predicted L3 SMM in both non-sarcopenic patients and healthy adults (r > 0.9), whereas the relationship was moderate in sarcopenic patients (r = 0.7633). The agreement between two measurements was good for healthy subjects and non-sarcopenic patients, while it was poor for sarcopenic patients. On ROC analysis, predicted L3 SMM showed poor diagnostic accuracy for sarcopenia.

CONCLUSIONS

A correlation between L3 and C3 SMMs was weak in sarcopenic patients. A prediction model also showed a poor diagnostic accuracy. Therefore, C3 SMM may not be a strong predictor for L3 SMM in sarcopenic patients with HNC.

FDG-PET/CT identified distant metastases and synchronous cancer in squamous cell carcinoma of the head and neck: the impact of smoking and P16-s

PURPOSE

Whole-body FDG-PET-CT is widely used at diagnosis of squamous cell carcinoma of the head and neck (SCCHN) but may identify suspicious lesions outside the neck that require investigation. This study evaluated the impact of smoking and P16-status on the incidence of malignant disease outside the head and neck region in newly diagnosed patients with SCCHN.

METHODS

All PET-positive foci outside the head-neck area were registered in 1069 patients planned for postoperative or curative intent radiotherapy with whole-body FDG-PET/CT from 2006 to 2012. All patient files were retrospectively investigated and clinical parameters, tobacco use, HPV (P16)-status and subsequent malignant disease registered.

RESULTS

Malignancy outside the neck was diagnosed in 9% of smokers, 2% of never-smokers, and 5% of patients with P16-positive oropharyngeal squamous cell carcinoma (OPSCC). Clinically suspicious PET-positive foci outside the head-neck were malignant in 55% of smokers, 34% of never-smokers, and in 38% of P16-pos OPSCC. All but two patients with cancer occurring outside the head and neck region were smokers.

CONCLUSION

Malignancy outside the neck at diagnosis was more frequent in smokers compared to non-smokers or P16-pos OPSCC. A high proportion of clinically suspicious PET-positive foci were non-malignant.

[18F]PARPi Imaging Is Not Affected by HPV Status In Vitro

Background

Human papillomavirus- (HPV-) associated oropharyngeal squamous cell carcinomas (OPSCCs) are clinically and pathologically distinct from HPV-negative tumors. Here, we explore whether HPV affects functional biomarkers, including γH2AX, RAD51, and PARP1. Moreover, the role of [18F]PARPi as a broadly applicable imaging tool for head and neck carcinomas is investigated.

Methods

HPV-positive and HPV-negative cell lines were used to evaluate the γH2AX, RAD51, and PARP1 expression with immunoblotting and immunofluorescence. Effects of external beam ionizing radiation were investigated in vitro, and survival was investigated via colony-formation assay. [18F]PARPi uptake experiments were performed on HPV-negative and HPV-positive cell lines to quantify PARP1 expression. PARP1 IHC and γH2AX foci were quantified using patient-derived oropharyngeal tumor specimens.

Results

Differences in DNA repair were detected, showing higher RAD51 and γH2AX expression in HPV-positive cell lines. Clonogenic assays confirm HPV-positive cell lines to be significantly more radiosensitive. PARP1 expression levels were similar, irrespective of HPV status. Consequently, [18F]PARPi uptake assays demonstrated that this tracer is internalized in cell lines independently from their HPV status.

Conclusion

The HPV status, often used clinically to stratify patients, did not affect PARP1 levels, suggesting that PARP imaging can be performed in both HPV-positive and HPV-negative patients. This study confirms that the PET imaging agent [18F]PARPi could serve as a general clinical tool for oropharyngeal cancer patients.

Radiomics-based prediction of survival in patients with head and neck squamous cell carcinoma based on pre- and post-treatment 18F-PET/CT

BACKGROUND

18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-PET/CT) has been widely applied for the imaging of head and neck squamous cell carcinoma (HNSCC). This study examined whether pre- and post-treatment 18F-PET/CT features can help predict the survival of HNSCC patients.

RESULTS

Three radiomics features were identified as prognostic factors. Radiomics score calculated from these features significantly predicted overall survival (OS) and disease-free disease (DFS). The clinicopathological characteristics combined with pre- or post-treatment nomograms showed better ROC curves and decision curves than the nomogram based only on clinicopathological characteristics.

CONCLUSIONS

Combining clinicopathological characteristics with radiomics features of pre-treatment PET/CT or post-treatment PET/CT assessment of primary tumor sites as positive or negative may substantially improve prediction of OS and DFS of HNSCC patients.

METHODS

171 patients who received pre-treatment 18F-PET/CT scans and 154 patients who received post-treatment 18F-PET/CT scans with HNSCC in the Cancer Imaging Achieve (TCIA) were included. Nomograms that combined clinicopathological features with either pre-treatment PET/CT radiomics features or post-treatment assessment of primary tumor sites were constructed using data from 154 HNSCC patients. Receiver operating characteristic (ROC) curves and decision curves were used to compare the predictions of these models with those of a model incorporating only clinicopathological features.

Prediction of cervical metastasis and survival in cN0 oral cavity cancer using tumour 18F-FDG PET/CT functional parameters

PURPOSE

Oral cavity squamous cell carcinoma (OCC) can spread to the neck without apparent lymphadenopathy. Pretreatment detection or prediction of occult metastasis might contribute to proper management of clinically node-negative (cN0) OCC. We examined the role of tumour quantitative 18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) measurements for predicting OCC occult metastasis and survival.

METHODS

This study included 130 cN0 OCC patients who underwent ¹⁸F-FDG PET/CT scanning and subsequent curative surgery and neck dissection. Maximum, peak, and mean standardized uptake value (SUV_max, SUV_peak, and SUV_mean), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were measured on pretreatment ¹⁸F-FDG PET/CT. Binary logistic regression was used to identify factors predicting occult cervical metastasis. Univariate and multivariate Cox proportional hazard regression were used to find factors associated with overall survival (OS).

RESULTS

Pathological cervical metastasis (pN +) was found in 29 (22.3%) patients. Age, tumour differentiation, lymphovascular invasion, and T classification were significantly associated with pN + (all P < 0.05). After adjustment for these factors, MTV and TLG independently predicted pN + (P < 0.05). Invasion depth, lymphovascular invasion, T and N classifications, and overall TNM stage were significantly associated with OS. After adjustment for these factors, SUV_max and TLG independently predicted OS (all P < 0.05). Patients with TLG > 9.3 g had a 5.7-fold increased risk of overall mortality.

CONCLUSIONS

Tumour ¹⁸F-FDG PET/CT parameters might predict occult metastasis and survival in cN0 OCC patients.

Positive Predictive Value of Neck Imaging Reporting and Data System Categories 3 and 4 Posttreatment FDG-PET/CT in Head and Neck Squamous Cell Carcinoma

BACKGROUND AND PURPOSE

The Neck Imaging Reporting and Data System is a standardized reporting system intended to risk stratify patients treated for head and neck squamous cell carcinoma. The purpose of this study is to investigate the positive predictive value of the Neck Imaging Reporting and Data System categories 3 and 4 on posttreatment PET/CT in patients treated definitively for head and neck squamous cell carcinoma.

MATERIALS AND METHODS

We retrospectively identified patients treated definitively for head and neck squamous cell carcinoma between 2006 and 2018. Patients whose posttreatment PET/CT scans were interpreted as Neck Imaging Reporting and Data System 3 (suspicious) or 4 (definitive recurrence) at the primary site, regional nodes, or at distant sites were included. The reference standard was histopathology or unequivocal imaging or clinical evidence of treatment failure. The positive predictive values of Neck Imaging Reporting and Data System 3 and 4 posttreatment PET/CT were calculated.

RESULTS

Seventy-two of 128 patients with posttreatment PET/CT interpreted as Neck Imaging Reporting and Data System 3 at the primary site, regional nodes, or distant sites were proved to have treatment failure at the suspicious sites, yielding an overall positive predictive value of 56% (95% CI, 48%-65%). The positive predictive values of Neck Imaging Reporting and Data System 3 by subsite were as follows: primary site, 56% (44/79); regional nodes, 65% (34/52); and distant sites, 79% (42/53). All 69 patients with posttreatment PET/CT interpreted as Neck Imaging Reporting and Data System 4 had true treatment failure, yielding a positive predictive value of 100% (95% CI, 96%-100%): primary site, 100% (28/28); regional nodes, 100% (32/32); and distant sites, 100% (29/29).

CONCLUSIONS

The positive predictive value of Neck Imaging Reporting and Data System 3 on posttreatment PET/CT is relatively low. Thus, Neck Imaging Reporting and Data System 3 findings should be confirmed with tissue sampling before instituting new salvage treatment regimens to avoid unnecessary overtreatment and its associated toxicities. Neck Imaging Reporting and Data System 4 reliably indicates recurrent disease.

Correlation between apparent diffusion coefficients and metabolic parameters in hypopharyngeal squamous cell carcinoma: A prospective study with integrated PET/MRI

PURPOSE

Apparent diffusion coefficients (ADCs) derived from diffusion-weighted magnetic resonance imaging (DW-MRI) and metabolic parameters derived from ¹⁸F-FDG positron emission tomography (PET) are promising prognostic indicators for head and neck squamous cell carcinoma (SCC). However, the relationship between them remains unclear. This study aimed to investigate the relationship between ADCs and metabolic parameters in hypopharyngeal SCC (HSCC) using integrated PET/MRI.

MATERIALS AND METHODS

Twenty-seven patients with biopsy-proven HSCC underwent integrated ¹⁸F-FDG neck PET/MRI. ADCs of HSCC, including the mean and minimum ADC values (ADC_mean and ADC_min), were measured manually on ADC maps. Metabolic parameters of HSCC, including maximum and mean standardized uptake values (SUV_max and SUV_mean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), were calculated automatically on PET images. Spearman correlation coefficients were used to assess the relationships between ADCs and metabolic parameters in HSCC tumors as well as in tumor groups with different histological grading, clinical staging, and anatomical subsites. P values < 0.05 were considered statistically significant.

RESULTS

No significant correlation was observed between ADCs and ¹⁸F-FDG PET metabolic parameters in the entire cohort, except for a significant inverse correlation between ADC_mean and MTV (r = -0.556, P = 0.003). Furthermore, a significant inverse correlation was observed between ADC_mean and MTV of HSCC in the moderately to well differentiated group (r_ADCmean/MTV = -0.692, P = 0.006), stage III group (r_ADCmean/MTV = -0.758, P = 0.003), and pyriform sinus group (r_ADCmean/MTV = -0.665, P = 0.007), whereas no significant correlation was observed in the poorly differentiated group, stage IV group, or non-pyriform sinus group.

CONCLUSIONS

Inverse correlation between ADC_mean and MTV in the HSCC population was observed and the correlativity depended on histological grading, clinical staging, and anatomical subsites of HSCC.

Fluorine-18 labeled poly (ADP-ribose) polymerase1 inhibitor as a potential alternative to 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography in oral cancer imaging

OBJECTIVES

The evaluation of disease extent and post-therapy surveillance of head and neck cancer using 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) PET is often complicated by physiological uptake in normal tissues of the head and neck region, especially after surgery or radiotherapy. However, irrespective of low positive predictive values, [18F]FDG PET remains the standard of care to stage the disease and monitor recurrences. Here, we report the preclinical use of a targeted poly (ADP-ribose) polymerase1 (PARP1) binding PET tracer, fluorine-18 labeled poly (ADP-ribose) polymerase1 inhibitor ([18F]PARPi), as a potential alternative with greater specificity.

METHODS

Using an orthotopic xenograft mouse model injected with either FaDu or Cal 27 (human squamous cell carcinoma cell lines) we performed PET/CT scans with the 2 tracers and compared the results. Gamma counts and autoradiography were also assessed and correlated with histology.

RESULTS

The average retained activity of [18F]PARPi across cell lines in tumor-bearing tongues was 0.9 ± 0.3%ID/g, 4.1 times higher than in control (0.2 ± 0.04%ID/g). Autoradiography and histology confirmed that the activity arose almost exclusively from the tumor areas, with a signal/normal tissue around a ratio of 42.9 ± 21.4. In vivo, [18F]PARPi-PET allowed delineation of tumor from healthy tissue (p < .005), whereas [18F]FDG failed to do so (p = .209).

CONCLUSIONS AND IMPLICATIONS FOR PATIENT CARE

We demonstrate that [18F]PARPi is more specific to tongue tumor tissue than [18F]FDG. [18F]PARPi PET allows for the straightforward delineation of oral cancer in mouse models, suggesting that clinical translation could result in improved imaging of head and neck cancer when compared to [18F]FDG.

Simultaneous Integrated Boost Radiotherapy in Unresectable Stage IV (M0) Head and Neck Squamous Cell Cancer Patients: Daily Clinical Practice

AIM

To evaluate clinical outcome in locally-advanced stage IV (M0) head and neck cancer patients treated using intensity-modulated radiotherapy (IMRT) with simultaneous integrated boost (SIB) in daily clinical practice.

BACKGROUND

Despite SIB-IMRT has been reported as a feasible and effective advanced head and neck cancer treatment, there are few data about its concurrent use with systemic therapies.

MATERIAL AND METHODS

We reviewed 41 staged IV (M0) head and neck cancer patients treated in two radiotherapy units in the city of Messina (Italy) during the last six years, using intensity modulated techniques-SIB. 22/41 patients had concomitant chemotherapy or cetuximab. Acute and late toxicities, objective response (OR) rate, local control (LC) and overall survival (OS) have been evaluated.

RESULTS

37/41 patients received the planned doses of radiotherapy, 2 patients died during the therapy. The major acute regional toxicities were skin reaction and mucositis. A case of mandibular osteoradionecrosis was recorded. At completion of treatment, OR was evaluated in 38 patients: 32/38 patients (84.2%) had complete (55.3%) and partial (28.9%) response. The 1- and 5-year LC rates were 73.4% and 69.73%, respectively. The 1-, 3-, and 5-year OS rates were 85.93%, 51.49% and 44.14%, respectively. No statistically significant differences in outcomes have been observed in patients treated with radiotherapy alone vs. irradiation concomitant to chemo/biotherapy. The median OS was 45 months.

CONCLUSION

SIB-IMRT is safeand can be used with concomitant chemotherapy/biotherapy in real-life daily clinical practice. SIB-IMRT alone is a valid alternative in patients unfit for systemic therapies.

Prediction of the human papillomavirus status in patients with oropharyngeal squamous cell carcinoma by FDG-PET imaging dataset using deep learning analysis: A hypothesis-generating study

PURPOSE

To assess the diagnostic accuracy of imaging-based deep learning analysis to differentiate between human papillomavirus (HPV) positive and negative oropharyngeal squamous cell carcinomas (OPSCCs) using FDG-PET images.

METHODS

One hundred and twenty patients with OPSCC who underwent pretreatment FDG-PET/CT were included and divided into the training 90 patients and validation 30 patients cohorts. In the training session, 2160 FDG-PET images were analyzed after data augmentation process by a deep learning technique to create a diagnostic model to discriminate between HPV-positive and HPV-negative OPSCCs. Validation cohort data were subsequently analyzed for confirmation of diagnostic accuracy in determining HPV status by the deep learning-based diagnosis model. In addition, two radiologists evaluated the validation cohort image-data to determine the HPV status based on each tumor's imaging findings.

RESULTS

In deep learning analysis with training session, the diagnostic model using training dataset was successfully created. In the validation session, the deep learning diagnostic model revealed sensitivity of 0.83, specificity of 0.83, positive predictive value of 0.88, negative predictive value of 0.77, and diagnostic accuracy of 0.83, while the visual assessment by two radiologists revealed 0.78, 0.5, 0.7, 0.6, and 0.67 (reader 1), and 0.56, 0.67, 0.71, 0.5, and 0.6 (reader 2), respectively. Chi square test showed a significant difference between deep learning- and radiologist-based diagnostic accuracy (reader 1: P = 0.016, reader 2: P = 0.008).

CONCLUSIONS

Deep learning diagnostic model with FDG-PET imaging data can be useful as one of supportive tools to determine the HPV status in patients with OPSCC.

18F-FDG PET/CT versus CT/MR imaging for detection of neck lymph node metastasis in palpably node-negative oral cavity cancer

PURPOSE

Subclinical lymph node (LN) metastasis is associated with poor survival outcome in oral cavity squamous cell carcinoma (OCC), which alleges elective neck LN dissection. Preoperative detection of metastatic LNs may improve prognosis and proper management of OCC. We examined the clinical usefulness of fluorine 18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) for the detection of occult neck LN metastasis in OCC patients in comparison with conventional CT/magnetic resonance (MR) imaging.

METHODS

A total of 178 OCC patients with negative neck palpation findings were assessed prospectively with 18F-FDG PET/CT and CT/MR imaging. Histopathological analyses of neck dissection samples served as reference. Diagnostic values of 18F-FDG PET/CT versus CT/MR imaging were compared with the McNemar test and logistic regression with generalized estimating equations.

RESULTS

Forty-two patients (23.6%) had metastasis in 44 sides and 58 levels of the neck. The sensitivity for detection of occult metastasis was higher for 18F-FDG PET/CT than that for CT/MR imaging on a per-patient (69.1% vs 35.7%), per-side (70.5% vs 36.4%), and per-level (62.1% vs 29.3%) basis (all P ≤ 0.001). However, the specificity for metastatic detection was higher for CT/MR imaging than that for 18F-FDG PET/CT (all P < 0.005). 18F-FDG PET/CT improved detection of occult metastasis up to 33.4% in these patients compared to CT/MR imaging.

CONCLUSIONS

18F-FDG PET/CT can better detect occult neck metastasis than CT/MR imaging, which may potentially impact the clinical management of OCC patients.

Clinical utility of 18F-FDG PET/CT for patients with recurrent head and neck squamous cell carcinoma

Background: The accurate detection of distant metastases can facilitate appropriate treatment planning for patients with recurrent head and neck squamous cell carcinoma (HNSCC). Objectives: We evaluated the role of ¹⁸F-FDG PET/CT for distant metastasis diagnosis and survival prediction in patients with recurrent HNSCC. Materials and methods: This study included 95 consecutive patients with recurrent HNSCC and salvage treatments. McNemar's test was used to compare the detection of distant metastasis at recurrence using ¹⁸F-FDG PET/CT and contrast-enhanced chest and neck CT, and bone scintigraphy. Results: Thirty-two patients (34%) had distant metastases at recurrence. The sensitivity, specificity, accuracy, and positive and negative predictive values of ¹⁸F-FDG PET/CT for detecting chest and bone metastases were comparable to those of conventional imaging (p > .1). However, ¹⁸F-FDG PET/CT detected two additional distant metastatic lesions. After controlling for clinicopathological factors, a recurrent lesion with maximum standardized uptake value (SUV_max) >8.7 was identified as an independent predictor of poor overall survival (p = .001). Conclusions and significance: ¹⁸F-FDG PET/CT or conventional imaging is comparable with regard to detecting distant metastases of recurrent HNSCC. However, ¹⁸F-FDG PET/CT may detect additional metastatic lesions in unusual distant sites and the recurrent lesion SUV_max may predict patient survival after salvage treatments.

Predictive value of quantitative diffusion-weighted imaging and 18-F-FDG-PET in head and neck squamous cell carcinoma treated by (chemo)radiotherapy

BACKGROUND AND PURPOSE

In head and neck squamous cell carcinoma (HNSCC) (chemo)radiotherapy is increasingly used to preserve organ functionality. The purpose of this study was to identify predictive pretreatment DWI- and ¹⁸F-FDG-PET/CT-parameters for treatment failure (TF), locoregional recurrence (LR) and death in HNSCC patients treated by (chemo)radiotherapy.

MATERIALS AND METHODS

We retrospectively included 134 histologically proven HNSCC patients treated with (chemo)radiotherapy between 2012-2017. In 58 patients pre-treatment DWI and ¹⁸F-FDG-PET/CT were performed, in 31 patients DWI only and in 45 patients ¹⁸F-FDG-PET/CT only. Primary tumor (_PT) and largest lymph node (_LN) metastasis were quantitatively assessed for TF, LR and death. Multivariate analysis was performed for ¹⁸F-FDG-PET/CT and DWI separately and thereafter combined. In patients with both imaging modalities, positive and negative predictive value in TF and differences in LR and death, were assessed.

RESULTS

Mean follow-up was 25.6 months (interquartile-range; 14.0-37.1 months). Predictors of treatment failure, corrected for TNM-stage and HPV-status, were SUV_max-PT, ADC_max-PT, total lesion glycolysis (TLG_-LN), ADCp20_-LN (P = 0.049, P = 0.024, P = 0.031, P = 0.047, respectively). TLG_-PT was predictive for LR (P = 0.003). Metabolic active tumor volume (MATV_-PT) (P = 0.003), ADC_GTV-PT (P < 0.001), ADCSD (P = 0.048) were significant predictors for death. In patients with both imaging modalities SUV_max-PT remained predictive for treatment failure (P = 0.049), TLG-_LN for LR (P = 0.003) and ADC_GTV-PT for death (P < 0.001). Higher predictive value for treatment failure was found for the combination of SUV_max-PT and ADC_max-PT, compared to either one separately.

CONCLUSION

Both DWI- and ¹⁸F-FDG-PET/CT-parameters appear to have predictive value for treatment failure, locoregional recurrence and death. Combining SUV_max-PT and ADC_max-PT resulted in better prediction of treatment failure compared to single parameter assessment.

Utility of first positron emission tomography-computed tomography scan as a prognostic tool following treatment of sinonasal and skull base malignancies

BACKGROUND

The prognostic value of the first posttreatment whole body integrated positron emission tomography-computed tomography (PET/CT) scanning in patients with sinonasal/skull base malignancies is undetermined.

METHODS

We retrospectively reviewed the data of all patients that underwent surgery for sinonasal/skull base malignancies in 2000-2015. The results of the pretreatment and posttreatment PET/CT findings and the clinical course were retrieved.

RESULTS

Thirty-eight patients (average age 60.6 years, 20 males) were included. Sensitivity and specificity, positive predictive value, and negative predictive value of the first PET/CT scan for predicting persistent/recurrent disease were 85.7%, 87.5%, 80%, and 91.3%, respectively. Overall 5-year survival was significantly lower in the first posttreatment PET/CT-positive group (35%) compared to the PET/CT-negative group (93%) (P = .0008).

CONCLUSION

Posttreatment PET/CT findings are highly prognostic in patients with sinonasal/skull base malignancies. Negative findings on the first posttreatment PET/CT scan predict a significantly better overall survival.

Prediction of ultrasound guided fine needle aspiration cytology results by FDG PET-CT for lymph node metastases in head and neck squamous cell carcinoma patients

INTRODUCTION

Accurate assessment of cervical lymph node status is essential in patients with head and neck squamous cell carcinoma (HNSCC) as it influences prognosis and treatment decisions. During patient workup, lymph node status is often examined by ultrasound guided fine needle aspiration cytology (USgFNAC). ¹⁸F-Fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG PET-CT) is frequently used to assess primary tumor and distant metastases but provides information on lymph node status as well. It is possible that FDG PET-CT (if already made for abovementioned indications) can predict the results of USgFNAC in subgroups of lymph nodes based on FDG-uptake and size. The objective of this study is to identify maximum standardized uptake (SUVmax) and short axis diameter cutoff values of lymph nodes at which FDG PET-CT can reliably predict USgFNAC results.

METHODS

One hundred and seventeen patients with HNSCC were retrospectively analyzed. Patients were included when FDG PET-CT and USgFNAC were available. SUVmax measurements were performed and compared to the USgFNAC results.

RESULTS

Using USgFNAC as a reference standard, the area under the curve of the receiver operating curve was 0.91. At an SUVmax cutoff value of 4.9, the accuracy of FDG PET-CT was the highest (85%). Lymph nodes with short axis diameter ≥1.0 cm and SUVmax ≥4.9 were in 91% positive on USgFNAC. If SUVmax was below 2.2, no nodes were positive on USgFNAC. Of all lymph nodes 52% either had a short axis diameter ≥1.0 cm and SUVmax ≥4.9 or an SUVmax <2.2. FDG PET-CT and USgFNAC results were very similar in these nodes.

CONCLUSIONS

By measuring SUVmax values and minimal axial diameters of lymph nodes and using appropriate cutoff values, FDG PET-CT can predict the results of USgFNAC examinations in half of the examined lymph nodes. This information may lead to a reduction of USgFNAC examinations in HNSCC patients if FDG PET-CT is already performed for other indications.

Technical Note: U-net-generated synthetic CT images for magnetic resonance imaging-only prostate intensity-modulated radiation therapy treatment planning

PURPOSE

Clinical implementation of magnetic resonance imaging (MRI)-only radiotherapy requires a method to derive synthetic CT image (S-CT) for dose calculation. This study investigated the feasibility of building a deep convolutional neural network for MRI-based S-CT generation and evaluated the dosimetric accuracy on prostate IMRT planning.

METHODS

A paired CT and T2-weighted MR images were acquired from each of 51 prostate cancer patients. Fifteen pairs were randomly chosen as tested set and the remaining 36 pairs as training set. The training subjects were augmented by applying artificial deformations and feed to a two-dimensional U-net which contains 23 convolutional layers and 25.29 million trainable parameters. The U-net represents a nonlinear function with input an MR slice and output the corresponding S-CT slice. The mean absolute error (MAE) of Hounsfield unit (HU) between the true CT and S-CT images was used to evaluate the HU estimation accuracy. IMRT plans with dose 79.2 Gy prescribed to the PTV were applied using the true CT images. The true CT images then were replaced by the S-CT images and the dose matrices were recalculated on the same plan and compared to the one obtained from the true CT using gamma index analysis and absolute point dose discrepancy.

RESULTS

The U-net was trained from scratch in 58.67 h using a GP100-GPU. The computation time for generating a new S-CT volume image was 3.84-7.65 s. Within body, the (mean ± SD) of MAE was (29.96 ± 4.87) HU. The 1%/1 mm and 2%/2 mm gamma pass rates were over 98.03% and 99.36% respectively. The DVH parameters discrepancy was less than 0.87% and the maximum point dose discrepancy within PTV was less than 1.01% respect to the prescription.

CONCLUSION

The U-net can generate S-CT images from conventional MR image within seconds with high dosimetric accuracy for prostate IMRT plan.

Triple primary cancer of the head and neck, skin and prostate: A case report and literature review

Second primary cancer (SPC) is an important prognostic factor for patients with head and neck cancer (HNC); therefore, the association between the prognosis and development of SPC has been well-reported. The use of 2-[18F]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) is valuable to examine cancer stage, evaluate treatment responses and investigate suspected relapses or metastases. In the present study, the case of a male patient who was diagnosed with three primary cancer types, including well to moderately differentiated squamous cell carcinoma (SCC) of the mandible, axillary cutaneous poorly differentiated SCC and prostate adenocarcinoma, was described. Among these, mandible cancer was the first diagnosed when the patient was 70 years of age. Synchronous skin and prostate cancer (PRC) types then developed 3 years later. To the best of our knowledge, this is the first report of the aforementioned combination of cancer types. Postoperative FDG-PET was not performed as no lesions of recurrence or metastases of mandible cancer were found. Three years later, the PRC was asymptomatic and was incidentally detected by FDG-PET performed for a preoperative evaluation of skin cancer. It was indicated that FDG-PET could be utilized in patients with HNC due to there being no accurate FDG-PET protocol to detect SPC over a long-term follow-up.

99m Tc-MIP-1404-SPECT/CT for the detection of PSMA-positive lesions in 225 patients with biochemical recurrence of prostate cancer

BACKGROUND

^99m Tc-MIP-1404 (Progenics Pharmaceuticals, Inc., New York, NY) is a novel, SPECT-compatible ^99m Tc-labeled PSMA inhibitor for the detection of prostate cancer. We present results of its clinical use in a cohort of 225 men with histologically confirmed prostate cancer referred for workup of biochemical relapse.

METHODS

From April 2013 to April 2017, ^99m Tc-MIP1404-scintigraphy was performed in 225 patients for workup of PSA biochemical relapse of prostate cancer. Whole-body planar and SPECT/CT images of the lower abdomen and thorax were obtained 3-4 h p.i. of 710 ± 64 MBq ^99m Tc-MIP-1404. Images were visually analyzed for presence and location of abnormal uptake. In addition, quantitative analysis of the SPECT/CT data was carried out on a subset of 125 patients. Follow-up reports of subsequent therapeutic interventions were available for 59% (139) of all patients.

RESULTS

Tracer-positive lesions were detected in 77% (174/225) of all patients. Detections occurred at the area of local recurrence in the prostate in 25% of patients (or a total of 56), with metastases in lymph nodes in 47% (105), bone in 27% (60), lung in 5% (12), and other locations in 2% (4) of patients. Detection rates were 90% at PSA levels ≥2 ng/mL and 54% below that threshold. Lesional SUVmax values were, on average, 32.2 ± 29.6 (0.8-142.2), and tumor-to-normal ratios 146.6 ± 160.5 (1.9-1482.4). The PSA level correlated significantly with total uptake of MIP-1404 in tumors (P < 0.001). Furthermore, total tumor uptake was significantly higher in patients with Gleason scores ≥8 compared to those with Gleason scores ≤7 (P < 0.05). In patients with androgen deprivation therapy, the detection rate was significantly higher compared to patients without androgen deprivation therapy (86% vs 71%, P < 0.001). Based on ^99m Tc-MIP-1404-imaging and other information, an interdisciplinary tumor board review recommended changes to treatment plans in 74% (104/139) of those patients for whom the necessary documentation was available.

CONCLUSION

SPECT/CT with ^99m Tc-labeled MIP-1404 has a high probability in detecting PSMA-positive lesions in patients with elevated PSA. Statistical analysis disclosed significant relationship between quantitative ^99m Tc-MIP-1404 uptake, PSA level, and Gleason score.

[Imaging diagnostic methods for identification of sentinel lymph nodes in patients with early squamous cell carcinoma of the oral cavity mucosa: a literature review]

The paper describes properties of clinical visualization approaches which are applied for detection of sentinel lymph nodes in patients suffering from oral cavity squamous cell cancer. Diagnostic efficiency results and technological features of different imaging techniques are discussed.

Clinical Practice in PET/CT for the Management of Head and Neck Squamous Cell Cancer

OBJECTIVE

The purpose of this article is to summarize the evidence for the value of PET/CT for the management of patients with head and neck squamous cell cancer and suggest best clinical practices.

CONCLUSION

FDG PET/CT is a valuable imaging tool for identifying unknown primary tumors in patients with known cervical node metastases leading to management change and is the standard of care for the initial staging of stage III and IV head and neck squamous cell carcinomas (HNSCCs), for assessing therapy response when performed at least 12 weeks after chemoradiation therapy, and for avoiding unnecessary planned neck dissection. Neck dissection is avoided if PET/CT findings are negative-regardless of the size of the residual neck nodes-because survival outcomes are not compromised. FDG PET/CT is valuable in detecting recurrences and metastases during follow-up when suspected because of clinical symptoms and serves as a prognostic marker for patient survival outcomes, for 5 years. Using FDG PET/CT for routine surveillance of HNSCC after 6 months of treatment without any clinical suspicion should be discouraged.

Contrast-enhanced ultrasound mapping of sentinel lymph nodes in oral tongue cancer-a pilot study

OBJECTIVES

To assess the usefulness of contrast-enhanced ultrasound (CEUS) with peritumoral injection of microbubble contrast agent for detecting the sentinel lymph nodes for oral tongue carcinoma.

METHODS

The study was carried out on 12 patients with T1-2cN0 oral tongue cancer. A radical resection of the primary disease was planned; a modified radical supraomohyoid neck dissection was reserved for patients with larger lesions (T2, n = 8). The treatment plan and execution were not influenced by sentinel node mapping outcome. The Sonovue^™ contrast agent (Bracco Imaging, Milan, Italy) was utilized. After detection, the position and radiologic features of the sentinel nodes were recorded.

RESULTS

The identification rate of the sentinel nodes was 91.7%; one patient failed to demonstrate any enhanced areas. A total of 15 sentinel nodes were found in the rest of the 11 cases, with a mean of 1.4 nodes for each patient. The sentinel nodes were localized in: Level IA-1 (6.7%) node; Level IB-11 (73.3%) nodes; Level IIA-3 (20.0%) nodes. No contrast-related adverse effects were observed.

CONCLUSIONS

For oral tongue tumours, CEUS is a feasible and potentially widely available approach of sentinel node mapping. Further clinical research is required to establish the position of CEUS detection of the sentinel nodes in oral cavity cancers.

Application of Multimodality Imaging Fusion Technology in Diagnosis and Treatment of Malignant Tumors under the Precision Medicine Plan

Objective:

The arrival of precision medicine plan brings new opportunities and challenges for patients undergoing precision diagnosis and treatment of malignant tumors. With the development of medical imaging, information on different modality imaging can be integrated and comprehensively analyzed by imaging fusion system. This review aimed to update the application of multimodality imaging fusion technology in the precise diagnosis and treatment of malignant tumors under the precision medicine plan. We introduced several multimodality imaging fusion technologies and their application to the diagnosis and treatment of malignant tumors in clinical practice.

Date Sources:

The data cited in this review were obtained mainly from the PubMed database from 1996 to 2016, using the keywords of “precision medicine”, “fusion imaging”, “multimodality”, and “tumor diagnosis and treatment”.

Study Selection:

Original articles, clinical practice, reviews, and other relevant literatures published in English were reviewed. Papers focusing on precision medicine, fusion imaging, multimodality, and tumor diagnosis and treatment were selected. Duplicated papers were excluded.

Results:

Multimodality imaging fusion technology plays an important role in tumor diagnosis and treatment under the precision medicine plan, such as accurate location, qualitative diagnosis, tumor staging, treatment plan design, and real-time intraoperative monitoring. Multimodality imaging fusion systems could provide more imaging information of tumors from different dimensions and angles, thereby offing strong technical support for the implementation of precision oncology.

Conclusion:

Under the precision medicine plan, personalized treatment of tumors is a distinct possibility. We believe that multimodality imaging fusion technology will find an increasingly wide application in clinical practice.