Comparison of PET/CT with conventional imaging modalities (USG, CECT) in evaluation of N0 neck in head and neck squamous cell carcinoma

Comparing the Efficacy of CT, MRI, PET-CT, and US in the Detection of Cervical Lymph Node Metastases in Head and Neck Squamous Cell Carcinoma with Clinically Negative Neck Lymph Node: A Systematic Review and Meta-Analysis

Background: Traditional imaging techniques have limited efficacy in detecting occult cervical lymph node (LN) metastases in head and neck squamous cell carcinoma (HNSCC). Positron emission tomography/computed tomography (PET-CT) has demonstrated potential for assessing HNSCC, but the literature on its efficacy for detecting cervical LN metastases is scarce and exhibits varied outcomes, hindering comparisons. Aim: To compare the efficacy of CT, MRI, PET-CT, and US for detecting LN metastasis in HNSCC with clinically negative neck lymph nodes. Methods: A systematic search was performed using Web of Science, PubMed, Scopus, Embase, and Cochrane databases. Studies comparing CT, MRI, PET-CT, or US to detect cervical metastases in HNSCC were identified. The quality of the studies was assessed using the QUADAS-2 instrument. The positive likelihood ratios (+LR) and negative likelihood ratios (-LR), sensitivity (SEN), specificity (SPE), and diagnostic odds ratio (DOR), with 95% confidence intervals (C.I.), were calculated. Analysis was stratified according to lymph node and patient basis. Results: Fifty-seven studies yielded 3791 patients. At the patient level, PET-CT exhibited the highest diagnostic performance, with a SEN of 74.5% (95% C.I.: 65.4-81.8%) and SPE of 83.6% (95% C.I.: 77.2-88.5%). PET-CT also demonstrated the highest +LR of 4.303 (95% C.I.: 3.082-6.008) and the lowest -LR of 0.249 (95% C.I.: 0.168-0.370), resulting in the highest DOR of 15.487 (95% C.I.: 8.973-26.730). In the evaluation of diagnostic parameters for various imaging modalities on node-based analysis results, MRI exhibited the highest SEN at 77.4%, and PET demonstrated the highest SPE at 96.6% (95% C.I.: 94.4-98%). PET-CT achieved the highest DOR at 24.353 (95% C.I.: 10.949-54.166). Conclusions: PET-CT outperformed other imaging modalities across the majority of studied metrics concerning LN metastasis detection in HNSCC.

FDG PET-CT for the Detection of Occult Nodal Metastases in Head and Neck Cancer: A Systematic Review and Meta-Analysis

Because of an estimated 20-30% prevalence of occult lymph node (LN) metastases in patients with head and neck squamous cell carcinoma (HNSCC), neck dissection is often proposed, despite its potential morbidity. In this systematic review and meta-analysis, the diagnostic performance of FDG PET-CT in detecting occult LN metastases was evaluated in patients with clinically negative necks (cN0) and in whom histopathology of a neck dissection specimen served as gold standard. Overall, 16 studies out of 2062 screened on PubMed and EMBASE fulfilled the inclusion criteria (n = 1148 patients). Seven of these sixteen studies were split into two or three studies because they contained data that could be processed distinctly in our meta-analysis. For this reason, a total of 25 studies were identified and included in the analysis (n total = 1918 patients). The overall prevalence of metastatic nodes per patient was 22.67%. The pooled sensitivity, specificity, diagnostic odds ratios, and negative predictive value (NPV) were 0.71 (95%CI: 0.66-0.75), 0.90 (95%CI: 0.84-0.93), 20.03 (95%CI: 13.51-29.70), and 0.92 (95%CI: 0.89-0.95), respectively. The main causes of inter-study heterogeneity included different reference standards (evaluation per patient, per neck side, or per neck level). The current meta-analysis showed that FDG PET-CT has a high specificity and NPV for ruling out nodal involvement in cN0 necks, but a limited sensitivity.

F18-FDG PET/CT accuracy in nodal staging of head and neck squamous cell carcinoma and correlation of SUVmax to the likelihood of a confirmed nodal metastasis

INTRODUCTION

This study aimed to determine F18-Fluorodeoxyglucose Positron Emission Tomography/ Computerised Tomography (FDG-PET/CT) accuracy in nodal staging of head and neck squamous cell carcinoma (HNSCC) and investigate the relationship between increasing standard uptake value max (SUV_max) thresholds and the likelihood of a diagnosis of nodal malignancy on histopathological analysis.

METHODS

Histopathological diagnosis was correlated retrospectively with the reported nodal involvement on PET/CT scans. Data was analysed to determine the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). SUV_max was measured for the most FDG-avid node in the nodal levels noted to be malignant on histopathological analysis and for those deemed malignant in the PET/CT report. A range of SUV_max thresholds was then applied retrospectively to calculate the corresponding likelihood of a node being truly malignant.

RESULTS

The "per lymph node level" analysis (n=216) found accuracy of 81.5%, sensitivity of 68.8%, specificity of 85.1%, PPV of 59.9% and NPV of 90.5%. A strong positive correlation was found between the threshold SUV_max and the likelihood of a diagnosis of malignancy on histopathological analysis. A significant increase in likelihood from 72.2% to 83.3% was found when the SUV_max threshold was increased from 4.0 to 4.5.

CONCLUSION

This study reinforces the utility of PET/CT as a diagnostic tool for ruling out malignant nodal dissemination due to its high NPV. Secondly, it shows a strong positive correlation between SUV_max of the lymph node and its likelihood of being malignant, which may assist in determining which lymph nodes should be biopsied.

18F-FDG-PET/CT interpretation pitfalls in patients with head and neck cancer

AIM

The aim of the present study is to raise awareness of ENT Surgeons on the limitations of ¹⁸F-FDG PET/CT in head and neck cancer by presenting illustrative cases from our department archives.

MATERIALS AND METHODS

A retrospective chart review was conducted for all patients with head and neck cancer treated in our ENT department from 2015 to 2020. Cases with various interpretation pitfalls due to false-positive and false-negative PET/CT results that lead to diagnostic dilemmas and treatment delays either in their pre-therapeutic work-up or in their post-therapeutic monitoring were included.

RESULTS

Five cases of various image interpretation pitfalls (3 false negative and 2 false positive cases) were identified and are presented in detail.

CONCLUSIONS

Although ¹⁸F-FDG PET/CT has gained in popularity and improved head and neck cancer management, clinicians should be aware of its limitations. The combination of ¹⁸F-FDG PET/CT with other imaging modalities can reduce the number of interpretation pitfalls but by no means will substitute sound clinical judgement.

Evaluation of the Prognostic Value of FDG PET/CT Parameters for Patients With Surgically Treated Head and Neck Cancer: A Systematic Review

Importance

Head and neck squamous cell cancer (HNSCC) represents the seventh most frequent cancer worldwide. More than half of the patients diagnosed with HNSCC are treated with primary surgery.

Objective

To report the available evidence on the value of quantitative parameters of fluorodeoxyglucose F 18-labeled positron emission tomography and computed tomography (FDG-PET/CT) performed before surgical treatment of HNSCC to estimate overall survival (OS), disease-free survival (DFS), and distant metastasis (DM) and to discuss their limitations.

Evidence Review

A systematic review of the English-language literature in PubMed/MEDLINE and ScienceDirect published between January 2003 and February 15, 2019, was performed between March 1 and July 27, 2019, to identify articles addressing the association between preoperative FDG-PET/CT parameters and oncological outcomes among patients with HNSCC. Articles included those that addressed the following: (1) cancer of the oral cavity, oropharynx, hypopharynx, or larynx; (2) surgically treated (primary or for salvage); (3) pretreatment FDG-PET/CT; (4) quantitative or semiquantitative evaluation of the FDG-PET/CT parameters; and (5) the association between the value of FDG-PET/CT parameters and clinical outcomes. Quality assessment was performed using the Oxford Centre for Evidence-Based Medicine level of evidence.

Findings

A total of 128 studies were retrieved from the databases, and 36 studies met the inclusion criteria; these studies comprised 3585 unique patients with a median follow-up of 30.6 months (range, 16-53 months). Of these 36 studies, 32 showed an association between at least 1 FDG-PET/CT parameter and oncological outcomes (OS, DFS, and DM). The FDG-PET/CT volumetric parameters (metabolic tumor volume [MTV] and total lesion glycolysis [TLG]) were independent prognostic factors in most of the data, with a higher prognostic value than the maximum standard uptake value (SUVmax). For example, in univariate analysis of OS, the SUVmax was correlated with OS in 5 of 11 studies, MTV in 11 of 12 studies, and TLG in 6 of 9 studies. The spatial distribution of metabolism via textural indices seemed promising, although that factor is currently poorly evaluated: only 3 studies analyzed data from radiomics indices.

Conclusions and Relevance

The findings of this study suggest that the prognostic effectiveness of FDG-PET/CT parameters as biomarkers of OS, DFS, and DM among patients with HNSCC treated with surgery may be valuable. The volumetric parameters (MTV and TLG) seemed relevant for identifying patients with a higher risk of postsurgical disease progression who could receive early therapeutic intervention to improve their prognosis. However, further large-scale studies including exclusively surgery-treated patients stratified according to localization and further analysis of the textural indices are required to define a reliable FDG-PET/CT-based prognostic model of mortality and recurrence risk for these patients.

FDG-PET/CT and Pathology in Newly Diagnosed Head and Neck Cancer: ACRIN 6685 Trial, FDG-PET/CT cN0

OBJECTIVE

FDG-PET/CT (fluorodeoxyglucose-positron emission tomography/computed tomography) is effective to assess for occult neck nodal disease. We report risks and patterns of nodal disease based on primary site and nodal level from data on the dissected cN0 per the results from ACRIN 6685.

STUDY DESIGN

Prospective nonrandomized enrollment included participants with first-time head and neck squamous cell carcinoma and at least 1 cN0 neck side to be dissected.

SETTING

Twenty-four ACRIN-certified centers internationally (American College of Radiology Imaging Network).

METHODS

A total of 287 participants were enrolled. Preoperative FDG-PET/CT findings were centrally reviewed and compared with pathology. Incidence, relative risk, pattern of lymph node involvement, and impact upon neck dissection were reported.

RESULTS

An overall 983 nodal levels were dissected (n = 261 necks, n = 203 participants). The highest percentages of ipsilateral positive nodes by primary location and nodal level were oral cavity (level I, 17/110, 15.5%), pharynx (level II, 6/30, 20.0%), and larynx (level VI, 1/3, 33.3%).

CONCLUSION

Levels at greatest risk for nodal disease in cN0 in terms of ipsilateral neck dissection are level I (oral cavity), II (pharynx), and VI (larynx). These data should be considered when treating patients presenting with cN0. This is the first study to comprehensively report the incidence, location, and risk of metastases in cN0 in the FDG-PET/CT era.

Surgical consensus guidelines on sentinel node biopsy (SNB) in patients with oral cancer

BACKGROUND

The eighth international symposium for sentinel node biopsy (SNB) in head and neck cancer was held in 2018. This consensus conference aimed to deliver current multidisciplinary guidelines. This document focuses on the surgical aspects of SNB for oral cancer.

METHOD

Invited expert faculty selected topics requiring guidelines. Topics were reviewed and evidence evaluated where available. Data were presented at the consensus meeting, with live debate from panels comprising expert, nonexpert, and patient representatives followed by voting to assess the level of support for proposed recommendations. Evidence review, debate, and voting results were all considered in constructing these guidelines.

RESULTS/CONCLUSION

A range of topics were considered, from patient selection to surgical technique and follow-up schedule. Consensus was not achieved in all areas, highlighting potential issues that would benefit from prospective studies. Nevertheless these guidelines represent an up-to-date pragmatic recommendation based on current evidence and expert opinion.

Diagnostic accuracy of F-18 FDG PET or PET/CT for detection of lymph node metastasis in clinically node negative head and neck cancer patients; A systematic review and meta-analysis

OBJECTIVE

The purpose of the current study was to investigate the diagnostic performance of F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) or positron emission tomography/computed tomography (PET/CT) for the detection of cervical lymph node (LN) metastasis in clinically node negative head and neck squamous cell cancer (cN0 HNSCC) patients through a systematic review and meta-analysis.

METHODS

The PubMed and EMBASE database, from the earliest available date of indexing through April 30, 2018, were searched for studies evaluating the diagnostic performance of F-18 FDG PET or PET/CT for the detection of LN metastasis in cN0 HNSCC patients. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic (SROC) curves.

RESULTS

Across 18 studies (1044 patients), the pooled sensitivity for F-18 FDG PET or PET/CT for the detection of LN metastasis was 0.58 and a pooled specificity of 0.87 for patient based analysis. Neck side based analysis showed the pooled sensitivity of 0.67 and a pooled specificity of 0.85. Level based study demonstrated the pooled sensitivity of 0.53 and a pooled specificity of 0.97 (95% CI; 0.95-0.98). In meta-regression analysis, no definite variable was the source of the study heterogeneity.

CONCLUSION

The current meta-analysis showed the low sensitivity and moderate specificity of F-18 FDG PET/CT for the detection of cervical LN metastasis in cN0 HNSCC patients. Level based analysis of F-18 FDG PET or PET/CT has a high specificity and NPV for the detection of cervical metastatic LN detection.

Multicenter Trial of [18F]fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Staging of Head and Neck Cancer and Negative Predictive Value and Surgical Impact in the N0 Neck: Results From ACRIN 6685

PURPOSE

The objective of this study was to determine the negative predictive value (NPV) of positron emission tomography (PET)/computed tomography (CT) for the clinically N0 neck on the basis of neck dissection.

METHODS

Participants with newly diagnosed, first-time, head and neck squamous cell carcinoma (HNSCC) and at least one clinically N0 neck side for which dissection was planned were included. A total of 287 participants were prospectively enrolled from 23 American College of Radiology Imaging Network-qualified institutions. PET/CT was compared with findings at neck dissection.

RESULTS

PET/CT scans and pathology findings were available for 270 N0 neck sides from 212 participants. For visual assessment, the NPV specific to the clinical-N0 sides was 0.868 (95% CI, 0.803 to 0.925). For dichotomized maximum standardized uptake value, the NPVs specific to the nodal basins were 0.940 (95% CI, 0.928 to 0.952) and 0.937 (95% CI, 0.925 to 0.949) at prespecified cutoffs of 2.5 and 3.5, respectively. The optimal cutoff maximum standardized uptake value was determined to be 1.8, with an NPV of 0.942 (95% CI, 0.930 to 0.953). The PET/CT-informed surgical treatment plan was changed in 51 of 237 participants (22%) compared with the PET/CT-blinded surgical plan. In 34 participants (14%), this led to planned dissection of additional nodal levels. In 12 participants (5%), this led to fewer planned dissected nodal levels. Negative PET/CT scans in N0 necks was true negative in 87% and false negative in 13%.

CONCLUSION

[¹⁸F]fluorodeoxyglucose-PET/CT has high NPV for the N0 neck in T2 to T4 HNSCC. The surgical treatment plans on the basis of PET/CT findings may be changed in approximately 22% of this group. These findings suggest that [¹⁸F]fluorodeoxyglucose-PET/CT may assist the clinician in deciding on the best therapy for the clinically N0 neck in HNSCC. Well-designed clinical trials should be performed to test the outcome of omitting neck dissection by using PET/CT.

The assessment of the accuracy of clinical preoperative lymph node

PURPOSE

The aim of the present study is to assess the accuracy of clinical preoperative lymph node and to define the degree of relation between the clinical preoperative assessment and histopathological examination in patients with head and neck cancer and cN+.

METHODS

This retrospective study was performed on 125 patients (85 males and 40 females) at the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Zhengzhou University, between December 2012 and December 2014.

RESULT

Of all the patients who underwent neck dissection, 37 were found with no neck metastasis. Positive or suspected lymph nodes were detected at computed tomography (CT) in 44 and detected at ultrasonogram diagnosis (USG) in 38 of 125 patients, and the necks were assessed as normal in 55 (44%) by both USG and CT.

CONCLUSION

Further investigation is needed to evaluate the rates of overall survival and disease-free survival of these N0 patients with neck dissection.

Molecular Imaging and Oral Cancer Diagnosis and Therapy

Oral cancer is known as one of relatively common type of cancer worldwide. Despite the easy access of the oral cavity to examination, oral tumors are diagnosed in more advanced stages of the disease. Imaging techniques have been recently emerged as non-invasive approaches to detect molecular and cellular changes in living cells and organisms. These techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) could help physicians to screen patients with oral tumors particularly oral squamous cell carcinoma (OSCC) in early stage of the disease. In this review, we discuss that early detection and diagnosis of oral tumors through using more robust and precise imaging techniques and a variety of cellular/molecular biomarkers not only could lead to more effective and less aggressive form of treatment for the disease but also could improve survival rates and lower treatment costs. J. Cell. Biochem. 118: 3055-3060, 2017. © 2017 Wiley Periodicals, Inc.